Willis Towers Watson Public Limited (WTW) 10-K 24 Feb 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2014	Feb. 20, 2015	Jun. 30, 2014
Document and Entity Information [Abstract]
Entity Registrant Name	WILLIS GROUP HOLDINGS PLC
Entity Central Index Key	1140536
Document Type	10-K
Document Period End Date	31-Dec-14
Amendment Flag	FALSE
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	-19
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$7,746,228,885
Entity Common Stock, Shares Outstanding		179,479,552

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
REVENUES
Commissions and fees	$3,767	$3,633	$3,458
Gross Investment Income, Operating	16	15	18
Other income	19	7	4
Total revenues	3,802	3,655	3,480
EXPENSES
Salaries and benefits	-2,314	-2,207	-2,475
Other operating expenses	-659	-636	-600
Depreciation expense	-92	-94	-79
Amortization of intangible assets	-54	-55	-59
Goodwill impairment charge	0	0	-492
Restructuring Costs	-36	0	0
Total expenses	-3,155	-2,992	-3,705
OPERATING (LOSS) INCOME	647	663	-225
Other Nonoperating Income (Expense)	6	22	16
Loss on extinguishment of debt	0	-60	0
Interest expense	-135	-126	-128
(Loss) Income from continuing operations before income taxes and interest in earnings of associates	518	499	-337
Income taxes	-159	-122	-101
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	359	377	-438
Interest in earnings of associates, net of tax	14	0	5
Net income (loss)	373	377	-433
Less: net income attributable to noncontrolling interests	-11	-12	-13
NET (INCOME) LOSS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	362	365	-446
AMOUNTS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS SHAREHOLDERS
NET (INCOME) LOSS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$362	$365	($446)
BASIC EARNINGS PER SHARE
— Continuing operations	$2.03	$2.07	($2.58)
DILUTED EARNINGS PER SHARE
— Continuing operations	$2	$2.04	($2.58)
CASH DIVIDENDS DECLARED PER SHARE	$1.20	$1.12	$1.08

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net income (loss)	$373	$377	($433)
Other comprehensive income, net of tax:
Foreign currency translation adjustments	-183	20	46
Pension funding adjustment:
Foreign currency translation on pension funding adjustment	37	-10	-22
Net actuarial (loss) gain	-255	85	-167
Amortization of unrecognized actuarial loss	40	46	38
Amortization of unrecognized prior service gain and curtailment	-3	-4	-5
Defined Benefit Plan, Curtailments	2	0	0
Pension funding adjustment, net of tax	-179	117	-156
Net unrealized gain on derivative instruments
Gain on derivatives (effective element), Net of tax amount	-25	23	11
Reclassification adjustment on derivatives, Net of tax amount	-8	3	7
Derivative instruments adjustment, net of tax	-17	20	4
Other comprehensive (loss) income, net of tax	-379	157	-106
Comprehensive (loss) income	-6	534	-539
Less: Comprehensive income attributable to noncontrolling interests	-5	-12	-13
Comprehensive income attributable to Willis Group Holdings	-11	522	-552
Interest Rate Swaps [Member]
Net unrealized gain on derivative instruments
Gain on derivatives (effective element), Net of tax amount	0	0	2
Reclassification adjustment on derivatives, Net of tax amount	-4	-4	-4
Forward Exchange Contracts [Member]
Net unrealized gain on derivative instruments
Gain on derivatives (effective element), Net of tax amount	-25	8	9
Reclassification adjustment on derivatives, Net of tax amount	13	1	-3
Treasury Lock [Member]
Net unrealized gain on derivative instruments
Gain on derivatives (effective element), Net of tax amount	0	15	0
Reclassification adjustment on derivatives, Net of tax amount	($1)	$0	$0

Consolidated_Balance_Sheets

Consolidated Balance Sheets	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
	USD ($)	USD ($)	Nominal Value in Dollars [Member]	Nominal Value in Dollars [Member]	Nominal Value in Euros [Member]	Nominal Value in Euros [Member]
			USD ($)	USD ($)	EUR (€)	EUR (€)
Document Fiscal Year Focus	2014
CURRENT ASSETS
Cash and cash equivalents	$635	$796
Accounts receivable, net	1,044	1,041
Fiduciary assets	8,948	8,412
Deferred tax assets	12	15
Other current assets	214	197
Total current assets	10,853	10,461
NON-CURRENT ASSETS
Fixed assets, net	483	481
Goodwill	2,937	2,838
Other intangible assets, net	450	353
Investments in associates	169	176
Deferred tax assets	9	7
Pension benefits asset	314	278
Other non-current assets	220	206
Total non-current assets	4,582	4,339
TOTAL ASSETS	15,435	14,800
CURRENT LIABILITIES
Fiduciary liabilities	8,948	8,412
Deferred revenue and accrued expenses	619	586
Income taxes payable	33	21
Current portion of long-term debt	167	15
Deferred tax liabilities	21	25
Other current liabilities	444	415
Total current liabilities	10,232	9,474
NON-CURRENT LIABILITIES
Long-term debt	2,142	2,311
Liability for pension benefits	284	136
Deferred tax liabilities	128	56
Provisions for liabilities	194	206
Other non-current liabilities	389	374
Total non-current liabilities	3,137	3,083
Total liabilities	13,369	12,557
COMMITMENTS AND CONTINGENCIES	0	0
Redeemable Noncontrolling Interest, Equity, Carrying Amount	59	0
EQUITY
Ordinary shares (A) $0.000115 nominal value and (B) €1 nominal value			0	0	0	0
Preference shares, $0.000115 nominal value; Authorized: 1,000,000,000; Issued nil shares in 2014 and 2013	0	0
Additional paid-in capital	1,524	1,316
Retained earnings	1,530	1,595
Accumulated Other Comprehensive Income (Loss), Net of Tax	-1,066	-693
Treasury shares, at cost, 46,408 shares in 2014 and 2013, and 40,000 shares, €1 nominal value, in 2014 and 2013	-3	-3
Total Willis Group Holdings stockholders’ equity	1,985	2,215
Noncontrolling interests	22	28
Total equity	2,007	2,243
TOTAL LIABILITIES AND EQUITY	$15,435	$14,800

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
	United States of America, Dollars [Member]	United States of America, Dollars [Member]	Euro [Member]	Euro [Member]
	USD ($)	USD ($)	EUR (€)	EUR (€)
Ordinary shares, nominal value	$0.00	$0.00	€ 1	€ 1
Ordinary shares, shares authorized	4,000,000,000	4,000,000,000	40,000	40,000
Ordinary shares, shares issued	178,701,000	178,861,000	40,000	40,000
Preference shares, nominal value	$0.00	$0.00
Preference shares, shares authorized	1,000,000,000	1,000,000,000
Treasury shares, at cost			€ 1	€ 1
Treasury shares	46,408	46,408	40,000	40,000

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
CASH FLOWS FROM OPERATING ACTIVITIES
Net income (loss)	$373	$377	($433)
Adjustments to reconcile net income to total net cash provided by operating activities:
Goodwill impairment	0	0	492
Net gain on disposal of operations, fixed and intangible assets	-17	-7	0
Depreciation expense	92	94	79
Amortization of intangible assets	54	55	59
Amortization and write-off of cash retention awards	10	6	416
Net periodic (benefit) cost of defined benefit pension plans	-17	-4	2
Provision for doubtful accounts	4	3	16
Provision for deferred income taxes	66	39	54
Noncash movement on derivative instruments	-12	18	11
Excess tax benefits from share-based payment arrangements	-5	-2	-2
Share-based compensation	52	42	32
Redemption Premium	0	65	0
Undistributed earnings of associates	-9	8	-2
Effect of exchange rate changes on net income	39	-4	-14
Changes in operating assets and liabilities, net of effects from purchase of subsidiaries:
Accounts receivable	-66	-116	-17
Fiduciary assets	-887	804	111
Fiduciary liabilities	887	-804	-111
Cash incentives paid	-401	-346	-323
Funding of defined benefit pension plans	-122	-150	-143
Other assets	16	14	-1
Other liabilities	432	445	319
Movement on provisions	-12	24	-20
Total net cash provided by operating activities	477	561	525
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	6	12	5
Additions to fixed assets	-113	-112	-135
Additions to intangible assets	-4	-7	-2
Acquisitions of operations, net of cash acquired	-241	-30	-33
Payments to acquire other investments, net of distributions received	-10	-7	-7
Proceeds from Sale of Equity Method Investments	0	4	0
Proceeds from Divestiture of Businesses, Net of Cash Divested	86	20	0
Net cash (used in) provided by continuing investing activities	-276	-120	-172
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued	0	522	0
Debt issuance costs	-3	-8	0
Repayments of debt	-15	-536	-15
Payments of Debt Extinguishment Costs	0	-65	0
Proceeds from issue of other debt	0	0	1
Repurchase of shares	-213	0	-100
Proceeds from issue of shares	134	155	53
Excess tax benefits from share-based payment arrangements	5	2	2
Dividends paid	-210	-193	-185
Proceeds from Noncontrolling Interests	0	0	3
Acquisition of noncontrolling interests	-4	-4	-39
Dividends paid to noncontrolling interests	-17	-10	-11
Net cash provided by (used in) financing activities	-323	-137	-291
INCREASE IN CASH AND CASH EQUIVALENTS	-122	304	62
Effect of exchange rate changes on cash and cash equivalents	-39	-8	2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	796	500	436
CASH AND CASH EQUIVALENTS, END OF YEAR	$635	$796	$500

Consolidated_Statements_of_Cha

Consolidated Statements of Changes in Equity (USD $)	Total	Willis Group Holdings Shareholders' Equity	Noncontrolling Interest	Stockholders' Equity, Total [Member]	Redeemable noncontrolling interest [Member]	United States of America, Dollars [Member]
In Millions, except Share data, unless otherwise specified	USD ($)	USD ($)	USD ($)	USD ($)	USD ($)
Total Willis Group Holdings stockholders’ equity at Dec. 31, 2011		$2,486
Redeemable Noncontrolling Interest, Equity, Carrying Amount at Dec. 31, 2011					0
Balance, beginning of year at Dec. 31, 2011				2,517
Noncontrolling interests at Dec. 31, 2011			31
Additional Paid in Capital, Common Stock at Dec. 31, 2011		1,073
Accumulated other comprehensive loss, net of tax, beginning balance at Dec. 31, 2011	-744	-744
Treasury Stock, Value at Dec. 31, 2011		-3
Retained Earnings (Accumulated Deficit) at Dec. 31, 2011		2,160
Balance, beginning of year, shares at Dec. 31, 2011						173,830,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares repurchased						-2,797,000
Exercise of stock options and release of non-vested shares						2,122,000
Stock Issued During Period, Shares, Acquisitions						24,000
Stock Repurchased During Period, Value		-100		-100
Net income (loss)	-433	-446	13	-433	0
Dividends, Common Stock, Cash		-187	-11	-198	0
Other comprehensive (loss) income	-106	-106	0	-106	0
Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options		50		50
Issue of shares for acquisitions		1		1
Adjustments to Additional Paid in Capital, Share-based Compensation, Stock Options, Requisite Service Period Recognition		32		32
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests		-31	-8	-39	0
Noncontrolling Interest, Increase from Sale of Parent Equity Interest		2	1	3	0
Foreign currency translation		-2		-2
Accumulated Other Comprehensive Income (Loss), Net of Tax at Dec. 31, 2012	-850	-850
Redeemable Noncontrolling Interest, Equity, Carrying Amount at Dec. 31, 2012					0
Noncontrolling interests at Dec. 31, 2012			26
Total Willis Group Holdings stockholders’ equity at Dec. 31, 2012		1,699
Balance, end of year at Dec. 31, 2012				1,725
Additional Paid in Capital, Common Stock at Dec. 31, 2012		1,125
Treasury Stock, Value at Dec. 31, 2012		-3
Retained Earnings (Accumulated Deficit) at Dec. 31, 2012		1,427
Balance, end of year, shares at Dec. 31, 2012						173,179,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options and release of non-vested shares						5,682,000
Net income (loss)	377	365	12	377	0
Dividends, Common Stock, Cash		-197	-10	-207	0
Other comprehensive (loss) income	157	157	0	157	0
Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options		153		153
Adjustments to Additional Paid in Capital, Share-based Compensation, Stock Options, Requisite Service Period Recognition		42		42
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests		-4	0	-4	0
Accumulated Other Comprehensive Income (Loss), Net of Tax at Dec. 31, 2013	-693	-693
Redeemable Noncontrolling Interest, Equity, Carrying Amount at Dec. 31, 2013	0				0
Noncontrolling interests at Dec. 31, 2013	28		28
Total Willis Group Holdings stockholders’ equity at Dec. 31, 2013	2,215	2,215
Balance, end of year at Dec. 31, 2013	2,243			2,243
Additional Paid in Capital, Common Stock at Dec. 31, 2013	1,316	1,316
Treasury Stock, Value at Dec. 31, 2013	-3	-3
Retained Earnings (Accumulated Deficit) at Dec. 31, 2013	1,595	1,595
Balance, end of year, shares at Dec. 31, 2013						178,861,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares repurchased						-5,050,000
Exercise of stock options and release of non-vested shares						4,854,000
Stock Issued During Period, Shares, Acquisitions						36,000
Stock Repurchased During Period, Value		-213		-213
Net income (loss)	373	362	11	373	0
Dividends, Common Stock, Cash		-214	-17	-231	0
Other comprehensive (loss) income	-379	-373	-2	-375	-4
Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options		146		146
Issue of shares for acquisitions		1		1
Adjustments to Additional Paid in Capital, Share-based Compensation, Stock Options, Requisite Service Period Recognition		52		52
Noncontrolling Interest, Increase from Sale of Parent Equity Interest		0	2	2	63
Foreign currency translation		9		9
Accumulated Other Comprehensive Income (Loss), Net of Tax at Dec. 31, 2014	-1,066	-1,066
Redeemable Noncontrolling Interest, Equity, Carrying Amount at Dec. 31, 2014	59				59
Noncontrolling interests at Dec. 31, 2014	22		22
Total Willis Group Holdings stockholders’ equity at Dec. 31, 2014	1,985	1,985
Balance, end of year at Dec. 31, 2014	2,007			2,007
Additional Paid in Capital, Common Stock at Dec. 31, 2014	1,524	1,524
Treasury Stock, Value at Dec. 31, 2014	-3	-3
Retained Earnings (Accumulated Deficit) at Dec. 31, 2014	$1,530	$1,530
Balance, end of year, shares at Dec. 31, 2014						178,701,000

Nature_of_Operations

Nature of Operations	12 Months Ended
	Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
NATURE OF OPERATIONS
	1	NATURE OF OPERATIONS
	Willis provides a broad range of insurance and reinsurance broking and risk management consulting services to its clients worldwide, both directly and indirectly through its associates. The Company provides both specialized risk management advisory and consulting services on a global basis to clients engaged in specific industrial and commercial activities, and services to small, medium and large corporations through its retail operations.
	In its capacity as an advisor, insurance and reinsurance broker, the Company acts as an intermediary between clients and insurance carriers by advising clients on risk management requirements, helping clients determine the best means of managing risk, and negotiating and placing insurance risk with insurance carriers through the Company’s global distribution network.

Basis_of_Presentation_and_Sign

Basis of Presentation and Significant Accounting Policies	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES
	2	BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES
	Recent Accounting Pronouncements to be Adopted in Future Periods
	In April 2014, the Financial Accounting Standards Board ('FASB') issued Accounting Standards Update ('ASU') No. 2014-08, 'Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity'. This guidance changes the criteria for reporting discontinued operations and enhances the related disclosures around discontinued operations. The new guidance requires a disposal of a component of an entity or a group of components of an entity to be reported in discontinued operations if the disposal represents a strategic shift that has, or will have, a major effect on an entity’s operations and financial results. This guidance is effective for interim and annual periods beginning after December 15, 2014.
	In May 2014, the FASB issued ASU No. 2014-09, 'Revenue From Contracts With Customers'. The new standard supersedes most current revenue recognition guidance and eliminates industry-specific guidance. The ASU is based on the principle that an entity should recognize revenue to depict the transfer of goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The ASU also requires additional disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from customer contracts, including significant judgments and changes in judgments and assets recognized from costs incurred to fulfill a contract. The ASU becomes effective for the Company at the beginning of its 2017 fiscal year; early adoption is not permitted. Entities have the option of using either a full retrospective or a modified retrospective approach for the adoption of the new standard. The Company is currently assessing the impact that this standard will have on its consolidated financial statements.
	In June 2014, the FASB issued guidance on the accounting for stock compensation where share-based payment awards granted to employees required specific performance targets to be achieved in order for employees to become eligible to vest in the awards and such performance targets could be achieved after an employee completes the requisite service period. The amendment in this update requires a performance target that affects vesting and that could be achieved after the requisite service period to be treated as a performance condition. The guidance is applicable to the Company for interim and annual reporting periods beginning after December 15, 2015, although earlier adoption is permitted. The Company is currently assessing the impact that this standard will have on its consolidated financial statements.
	Recent Accounting Pronouncements Adopted During the Period
	In July 2013, the FASB issued ASU No. 2013-11, 'Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists', a consensus of the FASB Emerging Issues Task Force which provides guidance on financial statement presentation of an unrecognized tax benefit when a net operating loss carryforward ('NOL'), or similar tax loss, or a tax credit carryforward exists. Such unrecognized tax benefits are required to be presented as a reduction of a deferred tax asset for a NOL or other tax credit carryforward whenever the NOL or tax credit carryforward would be available to reduce the additional taxable income or tax due if the tax position is disallowed.
	The Company adopted this guidance prospectively from January 1, 2014 and has not applied the amendments to the prior years. Upon adoption in the first quarter of 2014, other non-current liabilities and deferred tax assets were reduced by $21 million.
	Significant Accounting Policies
	These consolidated financial statements conform to accounting principles generally accepted in the United States of America (‘US GAAP’). Presented below are summaries of significant accounting policies followed in the preparation of the consolidated financial statements.
	Certain reclassifications have been made to prior year amounts to conform to current year presentation. In particular, effective from January 1, 2014, the Company has made changes to the presentation of certain items within the Consolidated Statements of Operations. Foreign exchange gains and losses, primarily from balance sheet revaluation, and gains and losses from the disposal of operations, previously reported within 'Total operating expenses', are now reported in a new Statement of Operations line item, 'Other income (expense), net', which is reported below the 'Operating income (loss)' line item. Prior period amounts have been reclassified to conform to this presentation.
	Principles of Consolidation
	The accompanying consolidated financial statements include the accounts of Willis Group Holdings and its subsidiaries, which are controlled through the ownership of a majority voting interest. Intercompany balances and transactions have been eliminated on consolidation.
	Foreign Currency Translation
	Transactions in currencies other than the functional currency of the entity are recorded at the rates of exchange prevailing at the date of the transaction. Monetary assets and liabilities in currencies other than the functional currency are translated at the rates of exchange prevailing at the balance sheet date and the related transaction gains and losses are reported in the statements of operations. Certain intercompany loans are determined to be of a long-term investment nature. The Company records transaction gains and losses from remeasuring such loans as a component of other comprehensive income.
	Upon consolidation, the results of operations of subsidiaries and associates whose functional currency is other than the US dollar are translated into US dollars at the average exchange rate and assets and liabilities are translated at year-end exchange rates. Translation adjustments are presented as a separate component of other comprehensive income in the financial statements and are included in net income only upon sale or liquidation of the underlying foreign subsidiary or associated company.
	Use of Estimates
	The preparation of financial statements in conformity with US GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities as of the dates of the financial statements and the reported amounts of revenues and expenses during the year. In the preparation of these consolidated financial statements, estimates and assumptions have been made by management concerning: the valuation of intangible assets and goodwill (including those acquired through business combinations); the selection of useful lives of fixed and intangible assets; impairment testing; provisions necessary for accounts receivable, commitments and contingencies and accrued liabilities; long-term asset returns, discount rates and mortality rates in order to estimate pension liabilities and pension expense; income tax valuation allowances; and other similar evaluations. Actual results could differ from the estimates underlying these consolidated financial statements.
	Cash and Cash Equivalents
	Cash and cash equivalents primarily consist of time deposits with original maturities of three months or less.
	Fiduciary Assets and Fiduciary Liabilities
	In its capacity as an insurance agent or broker, the Company collects premiums from insureds and, after deducting its commissions, remits the premiums to the respective insurers; the Company also collects claims or refunds from insurers which it then remits to insureds.
	Fiduciary Assets
	Fiduciary assets comprise Fiduciary Receivables and Fiduciary Funds.
	Fiduciary Receivables
	Fiduciary receivables represent uncollected premiums from insureds and uncollected claims or refunds from insurers.
	Fiduciary Funds
	Fiduciary funds represent unremitted premiums received from insureds and unremitted claims or refunds received from insurers. Fiduciary funds are generally required to be kept in certain regulated bank accounts subject to guidelines which emphasize capital preservation and liquidity. Such funds are not available to service the Company’s debt or for other corporate purposes. Notwithstanding the legal relationships with insureds and insurers, the Company is entitled to retain investment income earned on fiduciary funds in accordance with industry custom and practice and, in some cases, as supported by agreements with insureds.
	The period for which the Company holds such funds is dependent upon the date the insured remits the payment of the premium to the Company, or the date the Company receives refunds from the insurers, and the date the Company is required to forward such payment to the insurer, or insured, respectively.
	In certain instances, the Company advances premiums, refunds or claims to insurance underwriters or insureds prior to collection. Such advances are made from fiduciary funds and are reflected in the accompanying consolidated balance sheets as fiduciary assets.
	Fiduciary Liabilities
	Fiduciary liabilities represent the obligations to remit fiduciary funds and fiduciary receivables to insurers or insureds.
	Accounts Receivable
	Accounts receivable are stated at estimated net realizable values. Allowances are recorded, when necessary, in an amount considered by management to be sufficient to meet probable future losses related to uncollectible accounts.
	Fixed Assets
	Fixed assets are stated at cost less accumulated depreciation. Expenditures for improvements are capitalized; repairs and maintenance are charged to expenses as incurred. Depreciation is computed using the straight-line method based on the estimated useful lives of assets.
	Depreciation on buildings and long leaseholds is calculated over the lesser of 50 years or the lease term. Depreciation on leasehold improvements is calculated over the lesser of the useful life of the assets or the remaining lease term. Depreciation on furniture and equipment is calculated based on a range of 3 to 10 years. Freehold land is not depreciated.
	Recoverability of Fixed Assets
	Long-lived assets are tested for recoverability whenever events or changes in circumstance indicate that their carrying amounts may not be recoverable. An impairment loss is recognized if the carrying amount of a long-lived asset is not recoverable and exceeds its fair value. Recoverability is determined based on the undiscounted cash flows expected to result from the use and eventual disposition of the asset or asset group. Long-lived assets and certain identifiable intangible assets to be disposed of are reported at the lower of carrying amount or fair value less cost to sell.
	Operating Leases
	Rentals payable on operating leases are charged straight line to expenses over the lease term as the rentals become payable.
	Goodwill and Other Intangible Assets
	Goodwill represents the excess of the cost of businesses acquired over the fair value of identifiable net assets at the dates of acquisition. The Company reviews goodwill for impairment annually and whenever facts or circumstances indicate that the carrying amounts may not be recoverable. In testing for impairment, the fair value of each reporting unit is compared with its carrying value, including goodwill. If the carrying amount of a reporting unit exceeds its fair value, the amount of an impairment loss, if any, is calculated by comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill.
	Acquired intangible assets are amortized over the following periods:
			Expected
		Amortization basis	life (years)
	Acquired client relationships	In line with underlying cashflows	5 to 20
	Acquired management contracts	Straight line	18
	Other intangible assets	Straight line	3 to 10
	Amortizable intangible assets are reviewed for impairment whenever events or changes in circumstances indicate that their carrying amounts may not be recoverable.
	Investments in Associates
	Investments are accounted for using the equity method of accounting if the Company has the ability to exercise significant influence, but not control, over the investee. Significant influence is generally deemed to exist if the Company has an equity ownership in the voting stock of the investee between 20 and 50 percent, although other factors, such as representation on the Board of Directors and the impact of commercial arrangements, are considered in determining whether the equity method of accounting is appropriate. Under the equity method of accounting the investment is carried at cost of acquisition, plus the Company’s equity in undistributed net income since acquisition, less any dividends received since acquisition.
	The Company periodically reviews its investments in associates for which fair value is less than cost to determine if the decline in value is other than temporary. If the decline in value is judged to be other than temporary, the cost basis of the investment is written down to fair value. The amount of any write-down is included in the statements of operations as a realized loss.
	All other equity investments where the Company does not have the ability to exercise significant influence are accounted for by the cost method. Such investments are not publicly traded.
	GS & Cie Groupe ('Gras Savoye') is the principal associate of the Company. It is France's leading insurance broker. The Company has a call option to purchase 100 percent of the capital of Gras Savoye, a decision on whether to exercise this or not will be taken by April 30, 2015, for exercise during 2016.
	The carrying amount of the Gras Savoye investment as of December 31, 2014 includes interest bearing vendor loans and convertible bonds issued by Gras Savoye of $41 million and $106 million respectively (2013: $46 million and $110 million, respectively).
	Derivative Financial Instruments
	The Company uses derivative financial instruments for other than trading purposes to alter the risk profile of an existing underlying exposure. Interest rate swaps have been used to manage interest risk exposures. Forward foreign currency exchange contracts are used to manage currency exposures arising from future income and expenses. The fair values of derivative contracts are recorded in other assets and other liabilities. The effective portions of changes in the fair value of derivatives that qualify for hedge accounting as cash flow hedges are recorded in other comprehensive income. Amounts are reclassified from other comprehensive income into earnings when the hedged exposure affects earnings. If the derivative is designated as, and qualifies as, an effective fair value hedge, the changes in the fair value of the derivative and of the hedged item attributable to the hedged risk are both recognized in earnings. The amount of hedge ineffectiveness recognized in earnings is based on the extent to which an offset between the fair value of the derivative and hedged item is not achieved. Changes in fair value of derivatives that do not qualify for hedge accounting, together with any hedge ineffectiveness on those that do qualify, are recorded in other operating expenses or interest expense as appropriate.
	The Company evaluates whether its contracts include clauses or conditions which would be required to be separately accounted for at fair value as embedded derivatives.
	Income Taxes
	The Company recognizes deferred tax assets and liabilities for the estimated future tax consequences of events attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating and capital loss and tax credit carry forwards. Deferred tax assets and liabilities are measured using enacted rates in effect for the year in which the differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of changes in tax rates is recognized in the statement of operations in the period in which the change is enacted. Deferred tax assets are reduced through the establishment of a valuation allowance at such time as, based on available evidence, it is more likely than not that the deferred tax assets will not be realized. The Company adjusts valuation allowances to measure deferred tax assets at the amount considered realizable in future periods if the Company’s facts and assumptions change. In making such determination, the Company considers all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax planning strategies and recent financial operations.
	Positions taken in the Company’s tax returns may be subject to challenge by the taxing authorities upon examination. The Company recognizes the benefit of uncertain tax positions in the financial statements when it is more likely than not that the position will be sustained on examination by the tax authorities upon lapse of the relevant statute of limitations, or when positions are effectively settled. The benefit recognized is the largest amount of tax benefit that is greater than 50 percent likely to be realized on settlement with the tax authority, assuming full knowledge of the position and all relevant facts. The Company adjusts its recognition of these uncertain tax benefits in the period in which new information is available impacting either the recognition or measurement of its uncertain tax positions. Such adjustments are reflected as increases or decreases to income taxes in the period in which they are determined.
	The Company recognizes interest and penalties relating to unrecognized tax benefits within income taxes.
Provisions for Liabilities
The Company is subject to various actual and potential claims, lawsuits and other proceedings. The Company records liabilities for such contingencies including legal costs when it is probable that a liability has been incurred before the balance sheet date and the amount can be reasonably estimated. To the extent such losses can be recovered under the Company’s insurance programs, estimated recoveries are recorded when losses for insured events are realized. Significant management judgment is required to estimate the amounts of such contingent liabilities and the related insurance recoveries. The Company analyzes its litigation exposure based on available information, including consultation with outside counsel handling the defense of these matters, to assess its potential liability. Contingent liabilities are not discounted.
Pensions
The Company has two principal defined benefit pension plans which cover approximately half of employees in the United States and United Kingdom. Both these plans are now closed to new entrants. New employees in the United Kingdom are offered the opportunity to join a defined contribution plan and in the United States are offered the opportunity to join a 401(k) plan. In addition to the Company’s UK and US defined benefit pension plans, the Company has several smaller defined benefit pension plans in certain other countries in which it operates including a US non-qualified plan and an unfunded plan in the UK.. Elsewhere, pension benefits are typically provided through defined contribution plans.
Defined benefit plans
The net periodic cost of the Company’s defined benefit plans are measured on an actuarial basis using the projected unit credit method and several actuarial assumptions the most significant of which are the discount rate and the expected long-term rate of return on plan assets. Other material assumptions include rates of participant mortality, the expected long-term rate of compensation and pension increases and rates of employee termination. Gains and losses occur when actual experience differs from actuarial assumptions. If such gains or losses exceed ten percent of the greater of plan assets or plan liabilities the Company amortizes those gains or losses over the average remaining service period or average remaining life expectancy as appropriate of the plan participants.
In accordance with US GAAP the Company records on the balance sheet the funded status of its pension plans based on the projected benefit obligation.
Defined contribution plans
Contributions to the Company’s defined contribution plans are recognized as they fall due. Differences between contributions payable in the year and contributions actually paid are shown as either other assets or other liabilities in the consolidated balance sheets.
Share-Based Compensation
The Company has equity-based compensation plans that provide for grants of restricted stock units and stock options
to employees and non-employee directors of the Company who perform services for the Company.
The Company expenses all equity-based compensation on a straight-line basis over the requisite service period based upon the fair value of the award on the date of grant, the estimated achievement of any performance targets and anticipated staff retention. The awards under equity-based compensation are classified as equity and included as a component of equity on the Company’s consolidated balance sheets, as the ultimate payment of such awards will not be achieved through use of the Company’s cash or other assets.
Revenue Recognition
Revenue includes insurance commissions, fees for services rendered, certain commissions receivable from insurance carriers, investment income and other income.
Brokerage income and fees negotiated in lieu of brokerage are recognized at the later of the policy inception date or when the policy placement is complete. Commissions on additional premiums and adjustments are recognized when approved by or agreed between the parties and collectability is reasonably assured.
Fees for risk management and other services are recognized as the services are provided. Consideration for negotiated fee arrangements for an agreed period covering multiple insurance placements, the provision of risk management and/or other services are allocated to all deliverables on the basis of their relative selling prices. The Company establishes contract cancellation reserves where appropriate: at December 31, 2014, 2013 and 2012, such amounts were not material.
Investment income is recognized as earned.
Other income comprises gains on disposal of intangible assets, which primarily arise from settlements through enforcing non-compete agreements in the event of losing accounts through producer defection or the disposal of books of business.

Employees

Employees	12 Months Ended
	Dec. 31, 2014
Compensation Related Costs [Abstract]
EMPLOYEES
	3	EMPLOYEES
	The average number of persons, including Executive Directors, employed by the Company is as follows:
		Years ended December 31,
		2014			2013			2012
	Total average number of employees for the year	18,200			17,900			17,500
	Salaries and benefits expense comprises the following:
		Years ended December 31,
		2014				2013			2012
		(millions)
	Salaries and other compensation awards including amortization and write-off of cash retention awards of $10 million, $6 million and $416 million	$	2,069			$	1,953		$	2,258
	Share-based compensation	52				42			32
	Severance costs	8				32			6
	Social security costs	147				135			133
	Retirement benefits — defined benefit plan (income) expense	(17		)		(4		)	2
	Retirement benefits — defined contribution plan expense	55				49			44
	Total salaries and benefits expense	$	2,314			$	2,207		$	2,475
	Severance Costs
	Severance costs that have arisen in the normal course of business amounted to $8 million in the year ended December 31, 2014 (2013: $4 million; 2012: $6 million).
	During the year ended December 31, 2013, the Company incurred additional salaries and benefits costs of $29 million of which $28 million related to severance costs, in relation to an Expense Reduction Initiative in the first quarter. These costs related to 207 positions that were eliminated.

ShareBased_Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
SHARE-BASED COMPENSATION
	4	SHARE-BASED COMPENSATION
	On December 31, 2014, the Company had a number of open share-based compensation plans, which provide for the grant of time-based options and performance-based options, time-based restricted stock units and performance-based restricted stock units, and various other share-based grants to employees. All of the Company’s share-based compensation plans under which any options, restricted stock units or other share-based grants are outstanding as at December 31, 2014 are described below. The compensation cost that has been recognized for those plans for the year ended December 31, 2014 was $52 million (2013: $42 million; 2012: $32 million). The total income tax benefit recognized in the statement of operations for share-based compensation arrangements for the year ended December 31, 2014 was $12 million (2013: $9 million; 2012: $9 million).
	2012 Equity Incentive Plan
	This plan, which was established on April 25, 2012, provides for the granting of incentive stock options, time-based or performance-based non-statutory stock options, share appreciation rights, restricted shares, time-based or performance-based restricted share units ('RSUs'), performance-based awards and other share-based grants or any combination thereof (collectively referred to as 'Awards') to employees, officers, directors and consultants ('Eligible Individuals') of the Company. The Board of Directors also adopted a sub-plan under the 2012 plan to provide an employee sharesave scheme in the United Kingdom.
	There are 13,776,935 shares available for grant under this plan. In addition, shares subject to awards that were granted under the Willis Group Holdings 2008 Share Purchase and Option Plan, that terminate, expire or lapse for any reason will be made available for future Awards under this Plan. Options are exercisable on a variety of dates, including from the second, third, fourth or fifth anniversary of grant. Unless terminated sooner by the Board of Directors, the 2012 Plan will expire 10 years after the date of its adoption. That termination will not affect the validity of any grants outstanding at that date.
	2008 Share Purchase and Option Plan
	This plan, which was established on April 23, 2008, provides for the granting of time and performance-based options, restricted stock units and various other share-based grants at fair market value to employees of the Company. The 2008 plan was terminated as at April 25, 2012 and no further grants will be made under this plan. Any shares available for grant under the 2008 plan were included in the 2012 Equity Incentive Plan availability.
	Options are exercisable on a variety of dates, including from the third, fourth or fifth anniversary of grant.
	Employee Stock Purchase Plans
	The Company adopted the Willis Group Holdings 2001 North America Employee Share Purchase Plan, which expired on May 31, 2011 and the Willis Group Holdings 2010 North America Employee Stock Purchase Plan, which expires on May 31, 2020. These plans provide certain eligible employees in the United States and Canada the ability to contribute payroll deductions to the purchase of Willis Group Holdings plc shares at the end of each offering period.
	Option Valuation Assumptions
	The fair value of each option is estimated on the date of grant using the Black-Scholes option pricing model that uses the assumptions noted in the following table. Expected volatility is based on historical volatility of the Company’s stock. The Company uses the simplified method set out in Accounting Standard Codification (‘ASC’) 718-10-S99 to derive the expected term of options granted as it does not have sufficient historical exercise data to provide a reasonable basis upon which to estimate the expected term. The risk-free rate for periods within the expected life of the option is based on the US Treasury yield curve in effect at the time of grant.
		Years ended December 31,
		2014		2013		2012
	Expected volatility	18.7	%	24.7	%	32.1	%
	Expected dividends	2.8	%	2.6	%	3.2	%
	Expected life (years)	4		4		5
	Risk-free interest rate	1.3	%	1.5	%	0.9	%
	A summary of option activity under the plans at December 31, 2014, and changes during the year then ended is presented below:
				Weighted			Weighted	Aggregate
				Average			Average	Intrinsic
				Exercise			Remaining
							Contractual
	(Options in thousands)	Options		Price(i)			Term	Value
								(millions)
	Time-based stock options
	Balance, beginning of year	7,983		$	35.95
	Granted	1,069		$	41
	Exercised	(2,795	)	$	34.65
	Forfeited	(362	)	$	37.31
	Expired	(212	)	$	36.05
	Balance, end of year	5,683		$	37.45		5 years	$	42
	Options vested or expected to vest at December 31, 2014	5,131		$	37.41		5 years	$	38
	Options exercisable at December 31, 2014	2,712		$	35.84		4 years	$	24
	Performance-based stock options
	Balance, beginning of year	5,260		$	32.8
	Exercised	(1,201	)	$	29.46
	Forfeited	(392	)	$	33.86
	Balance, end of year	3,667		$	33.78		3 years	$	40
	Options vested or expected to vest at December 31, 2014	3,376		$	33.64		3 years	$	38
	Options exercisable at December 31, 2014	2,829		$	32.81		3 years	$	34
	_________________________________
	(i)	Certain options are exercisable in pounds sterling and are converted to dollars using the exchange rate at December 31, 2014.
	The weighted average grant-date fair value of time-based options granted during the year ended December 31, 2014 was $5.33 (2013: $7.74; 2012: $6.98). The total intrinsic value of options exercised during the year ended December 31, 2014 was $22 million (2013: $32 million; 2012: $8 million). At December 31, 2014 there was $15 million of total unrecognized compensation cost related to nonvested share-based compensation arrangements under time-based stock option plans; that cost is expected to be recognized over a weighted average period of 2 years.
	There were no performance-based options granted during the year ended December 31, 2014 or the year ended December 31, 2013. The weighted average grant-date fair value of performance-based options was $7.61 in the year ended December 31, 2012. The total intrinsic value of options exercised during the year ended December 31, 2014 was $15 million (2013: $14 million; 2012: $5 million). At December 31, 2014 there was $2 million of total unrecognized compensation cost related to nonvested share-based compensation arrangements under performance-based stock option plans; that cost is expected to be recognized over a weighted-average period of 1 year.
	A summary of restricted stock unit activity under the Plans at December 31, 2014, and changes during the year then ended is presented below:
				Weighted
				Average
				Grant Date
	(Units awarded in thousands)	Shares		Fair Value
	Nonvested shares (restricted stock units)
	Balance, beginning of year	2,929		$	38.71
	Granted	1,750		$	43.03
	Vested	(858	)	$	37.19
	Forfeited	(327	)	$	37.62
	Balance, end of year	3,494		$	41.35
	The total number of restricted stock units vested during the year ended December 31, 2014 was 857,603 shares at an average share price of $44.09 (2013: 873,670 shares at an average share price of $41.10; 2012: 408,005 shares at an average price of $35.82). At December 31, 2014 there was $109 million of total unrecognized compensation cost related to nonvested share-based compensation arrangements under the plan; that cost is expected to be recognized over a weighted average period of 2 years.
	Cash received from option exercises under all share-based payment arrangements for the year ended December 31, 2014 was $134 million (2013: $155 million; 2012: $53 million). The actual tax benefit recognized for the tax deductions from option exercises of the share-based payment arrangements totaled $20 million for the year ended December 31, 2014 (2013: $28 million; 2012: $8 million).

Restructuring_Costs_Notes

Restructuring Costs (Notes)	12 Months Ended
	Dec. 31, 2014
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Activities Disclosure [Text Block]	operational improvement program designed to strengthen the Company’s client service capabilities and to deliver future cost savings (hereinafter referred to as the Operational Improvement Program). The main elements of the program, which is expected to be completed by the end of 2017, include the following:
	•	movement of more than 3,500 support roles from higher cost locations to Willis facilities in lower cost locations, bringing the ratio of employees in higher cost versus lower cost near-shore and off-shore centers from approximately 80:20 to approximately 60:40;
	•	net workforce reductions in support positions;
	•	lease consolidation in real estate and reductions in ratios of seats per employee and square footage of floor space per employee; and
	•	information technology systems simplification and rationalization.
	The program is expected to deliver cost savings of at least $420 million through 2017 and annual cost savings of $300 million starting 2018. To achieve these cost savings, the company is expecting to incur cumulative costs, including capital expenditure, of approximately $410 million through the end of 2017.
	The Company recognized restructuring costs of $36 million in the year ended December 31, 2014, related to its Operational Improvement Program.
	An analysis of the cost for restructuring recognized in the statement of operations in the year ended December 31, 2014, is as follows:
		Twelve months ended December 31, 2014
		North America			International			Global			Corporate		Total
		(millions)
	Termination benefits	$	3		$	3		$	10		$	—	$	16
	Professional services and other	—			2			1			17		20
	Total	$	3		$	5		$	11		$	17	$	36
	At December 31, 2014, the Company's liability under the Operational Improvement Program is as follows:
		Termination Benefits			Professional Services and other			Total
		(millions)
	Balance at January 1, 2014	$	—		$	—		$	—
	Charges incurred	16			20			36
	Cash payments	(11		)	(14		)	(25		)
	Balance at December 31, 2014	$	5		$	6		$	11

Auditors_Remuneration

Auditors' Remuneration	12 Months Ended
	Dec. 31, 2014
Auditors' Remuneration [Abstract]
AUDITORS' REMUNERATION
	6	AUDITORS’ REMUNERATION
	An analysis of auditors’ remuneration is as follows:
		Years ended December 31,
		2014		2013		2012
		(millions)
	Audit of group consolidated financial statements	$	5	$	4	$	4
	Other assurance services	2		3		3
	Other non-audit services	1		1		1
	Total auditors’ remuneration	$	8	$	8	$	8

Other_Expense_Income_Net_Other

Other (Expense) Income Net Other (Expense) Income Net (Notes)	12 Months Ended
	Dec. 31, 2014
Other Income and Expenses [Abstract]
Other Income Expense [Text Block]
	7	OTHER INCOME (EXPENSE), NET
	Other income (expense), net consists of the following:
		Years ended December 31,
		2014			2013		2012
		(millions)
	Gain (loss) on disposal of operations	$	12		$	2	$	(3	)
	Impact of Venezuelan currency devaluation	(14		)	—		—
	Foreign exchange gain	8			20		19
	Other income (expense), net	$	6		$	22	$	16

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
INCOME TAXES
	8	INCOME TAXES
	An analysis of income from continuing operations before income taxes and interest in earnings of associates by location of the taxing jurisdiction is as follows:
		Years ended December 31,
		2014			2013			2012
		(millions)
	Ireland	$	(65	)	$	(52	)	$	(47	)
	United States	92			(11		)	(615		)
	United Kingdom	154			282			25
	Other jurisdictions	337			280			300
	Income (loss) from continuing operations before income taxes and interest in earnings of associates	$	518		$	499		$	(337	)
	The provision for income taxes by location of the taxing jurisdiction consisted of the following:
		Years ended December 31,
		2014			2013			2012
		(millions)
	Current income taxes:
	US federal tax	$	(16	)	$	7		$	3
	US state and local taxes	7			3			1
	UK corporation tax	29			28			2
	Other jurisdictions	73			45			41
	Total current taxes	93			83			47
	Deferred taxes:
	US federal tax	30			10			(44		)
	US state and local taxes	10			1			(41		)
	Effect of US valuation allowance	5			2			113
	UK corporation tax	24			17			27
	Other jurisdictions	(3		)	9			(1		)
	Total deferred taxes	66			39			54
	Total income taxes	$	159		$	122		$	101
	The reconciliation between US federal income taxes at the statutory rate and the Company’s provision for income taxes on continuing operations is as follows:
		Years ended December 31,
		2014			2013			2012
		(millions, except percentages)
	Income (loss) from continuing operations before income taxes and interest in earnings of associates	$	518		$	499		$	(337	)
	US federal statutory income tax rate	35		%	35		%	35		%
	Income tax expense at US federal tax rate	181			175			(118		)
	Adjustments to derive effective rate:
	Non-deductible expenditure	21			19			15
	Tax impact of internal restructurings	—			11			—
	Movement in provision for unrecognized tax benefits	1			(1		)	6
	Impairment of non-qualifying goodwill	—			—			137
	Disposal of non-qualifying goodwill	11			—			—
	Impact of change in tax rate on deferred tax balances	—			(4		)	(3		)
	Adjustment in respect of prior periods	(2		)	1			6
	Non-deductible Venezuelan foreign exchange loss	5			—			—
	Effect of foreign exchange and other differences	(4		)	1			2
	Changes in valuation allowances applied to deferred tax assets	7			—			114
	Adjustments to eliminate the net tax effect of intra-group items	(30		)	(30		)	(31		)
	Tax differentials of foreign earnings:
	Foreign jurisdictions	(48		)	(54		)	(12		)
	US state taxes and local taxes	17			4			(15		)
	Provision for income taxes	$	159		$	122		$	101
	Willis Group Holdings plc is a non-trading holding company tax resident in Ireland where it is taxed at the statutory rate of 25%. The provision for income tax on continuing operations has been reconciled above to the US federal statutory tax rate of 35% due to significant operations in the US.
	The significant components of deferred income tax assets and liabilities and their balance sheet classifications are as follows:
		December 31,
		2014			2013
		(millions)
	Deferred tax assets:
	Accrued expenses not currently deductible	$	133		$	153
	US state net operating losses	76			70
	UK net operating losses	1			3
	Other net operating losses	12			5
	UK capital losses	39			43
	Accrued retirement benefits	109			47
Deferred compensation	34			37
Stock options	22			25
Gross deferred tax assets	426			383
Less: valuation allowance	(280		)	(196		)
Net deferred tax assets	$	146		$	187
Deferred tax liabilities:
Cost of intangible assets, net of related amortization	$	149		$	120
Cost of tangible assets, net of related amortization	38			44
Prepaid retirement benefits	62			56
Accrued revenue not currently taxable	25			23
Financial derivative transactions	—			3
Deferred tax liabilities	274			246
Net deferred tax (liability) asset	$	(128	)	$	(59	)
	December 31,
	2014			2013
	(millions)
Balance sheet classifications:
Current:
Deferred tax assets	$	12		$	15
Deferred tax liabilities	(21		)	(25		)
Net current deferred tax liabilities	(9		)	(10		)
Non-current:
Deferred tax assets	9			7
Deferred tax liabilities	(128		)	(56		)
Net non-current deferred tax liabilities	(119		)	(49		)
Net deferred tax liabilities	$	(128	)	$	(59	)
As a result of certain realization requirements of ASC 718 Compensation - Stock Compensation, the Company recognized $8 million of previously unrecognized deferred tax assets that arose directly from tax deductions related to equity compensation greater than compensation recognized for financial reporting. Equity was increased by this $8 million as of December 31, 2014.
At December 31, 2014, the Company had valuation allowances of $280 million (2013: $196 million) to reduce its deferred tax assets to estimated realizable value. The valuation allowances at December 31, 2014, relate to deferred tax assets arising from UK capital loss carryforwards ($39 million) and other net operating losses ($10 million), which have no expiration date, and to the deferred tax assets in the United States ($231 million). Included within US deferred tax assets are assets of $76 million in respect of US state net operating losses. These losses will expire as follows: $8 million from 2015 to 2018, $17 million from 2019 to 2023 and $51 million from 2024 to 2034. Capital loss carryforwards can only be offset against future UK capital gains.
	Balance at			Additions/			Other movements			Foreign			Balance
	beginning of year			(releases)						exchange differences			at
				charged to									end of year
Description				costs and expenses
	(millions)
Year Ended December 31, 2014
Deferred tax valuation allowance	$	196		$	17		$	67		$	—		$	280
Year Ended December 31, 2013
Deferred tax valuation allowance	221			15			(40		)	—			196
Year Ended December 31, 2012
Deferred tax valuation allowance	102			110			12			(3		)	221
The amount charged to tax expense in the table above differs from the effect of $7 million disclosed in the rate reconciliation primarily because the movement in this table includes effects of state taxes, which are disclosed separately in the rate reconciliation. The impact of Other movements is primarily recorded in other comprehensive income.
At December 31, 2014 the Company had deferred tax assets of $146 million (2013: $187 million), net of the valuation allowance. Management believes, based upon the level of historical taxable income and projections for future taxable income, it is more likely than not that the Company will realize the benefits of these deductible differences, net of the valuation allowance. However, the amount of the deferred tax asset considered realizable could be adjusted in the future if estimates of taxable income are revised.
The Company recognizes deferred tax balances related to the undistributed earnings of subsidiaries when the Company expects that it will recover those undistributed earnings in a taxable manner, such as through receipt of dividends or sale of the investments. The Company does not, however, provide for income taxes on the unremitted earnings of certain other subsidiaries where, in management’s opinion, such earnings have been indefinitely reinvested in those operations, or will be remitted either in a tax free liquidation or as dividends with taxes substantially offset by foreign tax credits. It is not practical to determine the amount of unrecognized deferred tax liabilities for temporary differences related to these investments.
Unrecognized tax benefits
Total unrecognized tax benefits as at December 31, 2014, totaled $19 million. During the next 12 months it is reasonably possible that the Company will recognize approximately $1 million of tax benefits related to the release of provisions for potential inter company pricing adjustments no longer required due to either settlement through negotiation or closure of the statute of limitations on assessment.
A reconciliation of the beginning and ending amounts of unrecognized tax benefits is as follows:
	2014			2013			2012
	(millions)
Balance at January 1	$	41		$	37		$	16
Reductions due to a lapse of the applicable statute of limitation	—			(5		)	(3		)
Increases for positions taken in current period	5			9			8
(Decreases) increases for positions taken in prior periods	(26		)	—			16
Other movements	(1		)	—			—
Balance at December 31	$	19		$	41		$	37
$19 million of the unrecognized tax benefits at December 31, 2014 would, if recognized, favorably affect the effective tax rate in future periods.
The Company files tax returns in the various tax jurisdictions in which it operates. US tax returns have been filed timely. Although tax years 2008 and 2009 are closed, the IRS could make adjustments (but not assess additional tax) up to the amount of the net operating losses carried forward from those years. The Company extended the federal statute of limitations for assessment in the United States for the 2010 year until March 15, 2015.
All UK tax returns have been filed timely and are in the normal process of being reviewed, by HM Revenue & Customs. There are no material ongoing inquiries in relation to filed UK returns. In other tax jurisdictions the Company is currently not subject to any examinations for any year prior to 2004.

Earnings_Per_Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
EARNINGS PER SHARE
	9	EARNINGS PER SHARE
	Basic and diluted earnings per share are calculated by dividing net income (loss) attributable to Willis Group Holdings by the average number of shares outstanding during each period. The computation of diluted earnings per share reflects the potential dilution that could occur if dilutive securities and other contracts to issue shares were exercised or converted into shares or resulted in the issue of shares that then shared in the net income of the Company.
	In periods where losses are reported the weighted average shares outstanding excludes potentially issuable shares described above, because their inclusion would be anti-dilutive.
	For the year ended December 31, 2014, time-based and performance-based options to purchase 5.7 million and 3.7 million shares (2013: 8.0 million and 5.3 million; 2012: 10.2 million and 6.5 million), respectively, and 3.5 million restricted stock units (2013: 2.9 million; 2012: 2.5 million) were outstanding.
	Basic and diluted earnings per share are as follows:
		Years ended December 31,
		2014			2013			2012
		(millions, except per share data)
	Net income (loss) attributable to Willis Group Holdings	$	362		$	365		$	(446	)
	Basic weighted average number of shares outstanding	178			176			173
	Dilutive effect of potentially issuable shares	3			3			—
	Diluted weighted average number of shares outstanding	181			179			173
	Basic earnings per share:
	Net income (loss) attributable to Willis Group Holdings shareholders	$	2.03		$	2.07		$	(2.58	)
	Dilutive effect of potentially issuable shares	(0.03		)	(0.03		)	—
	Diluted earnings per share:
	Net income (loss) attributable to Willis Group Holdings shareholders	$	2		$	2.04		$	(2.58	)
	Options to purchase 2.4 million shares and 1.5 million restricted stock units for the year ended December 31, 2014, were not included in the computation of the dilutive effect of stock options because the effect was antidilutive (2013: 2.1 million shares and 1.3 million restricted stock units; 2012: 16.7 million shares and 2.5 million restricted stock units).

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2014
Business Combinations [Abstract]
ACQUISITIONS
	10	ACQUISITIONS
	During the years ended December 31, 2014 and 2013 we made the following material acquisitions in line with our strategy to invest in targeted acquisitions with a focus on earnings accretion, competitive position, and fit.
	Max Matthiessen Holding AB
	In the fourth quarter of 2014, the Company acquired 75.8 percent of Max Matthiessen Holding AB and subsidiaries (collectively referred to as Max Matthiessen), a leading employee benefits adviser in Sweden, for cash consideration of $204 million.
	On acquisition the Company recognized acquired intangible assets of $134 million of which $56 million was in relation to client relationships and $76 million was in relation to fund management contracts, which are being amortized over 12 years and 18 years respectively. The remaining $2 million of intangible assets relate to the Max Matthiessen trade name and is being amortized over 4 years.
	Goodwill of $139 million was recognized on the transaction.
	Charles Monat Limited
	In the second quarter of 2014, the Company acquired 100 percent of Charles Monat Limited and its subsidiaries (collectively referred to as Charles Monat), a life insurance solutions adviser to high net worth clients based in Hong Kong, for cash consideration of $59 million.
	Additional consideration estimated at $29 million is payable in annual installments over the next 5 years, based on a multiple of EBITDA of the entities acquired, during the period from May 25, 2014 until September 2, 2019. This consideration has been assessed to have a fair value of $12 million at the date of acquisition.
	On acquisition the Company recognized acquired intangible assets of $35 million of which $27 million was in respect of client relationships, which are being amortized over an expected life of 11 years. The remaining $8 million of intangible assets relate to carrier relationships and trade names and are both being amortized over 5 years.
	Goodwill of $31 million was recognized on the transaction.
	Prime Professions Ltd
	In second quarter 2013, the Company acquired 100 percent of PPH Limited and its subsidiary Prime Professions Limited (together referred to as Prime Professions), a leading UK based professional indemnity insurance broker, for cash consideration of $29 million. Additional consideration of up to approximately $2 million is payable in 2015 based on the achievement of certain revenue targets.
	In relation to the acquisition of Prime Professions, the Company recognized acquired intangible assets of $17 million of which $16 million was in respect of client relationships, which are being amortized over an expected life of 15 years. The remaining intangible assets relate to non-compete agreements and the Prime trade name which are being amortized over 8 years and 3 years, respectively.
	Goodwill of $15 million was recognized on the transaction.
	The aggregate costs incurred related to the above acquisitions for the year ended December 31, 2014 was $3 million (2013: $1 million)
	In addition to the above acquisitions, the Company completed a number of smaller acquisitions during 2014 for aggregated consideration of $27 million and consequently recognised intangible assets of $16 million and goodwill of $14 million.

Fixed_Assets_Net

Fixed Assets, Net	12 Months Ended
	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
FIXED ASSETS, NET
	11	FIXED ASSETS, NET
	An analysis of fixed asset activity for the years ended December 31, 2014 and 2013 are as follows:
		Land and			Leasehold			Furniture and			Total
		buildings (i)			improvements			equipment
		(millions)
	Cost: at January 1, 2013	$	78		$	227		$	576		$	881
	Additions	10			22			80			112
	Disposals	—			(7		)	(43		)	(50		)
	Foreign exchange	1			—			5			6
	Cost: at December 31, 2013	89			242			618			949
	Additions	7			25			84			116
	Disposals	—			(12		)	(29		)	(41		)
	Foreign exchange	(3		)	(10		)	(31		)	(44		)
	Cost: at December 31, 2014	$	93		$	245		$	642		$	980
	Depreciation: at January 1, 2013	$	(32	)	$	(75	)	$	(306	)	$	(413	)
	Depreciation expense provided	(3		)	(18		)	(73		)	(94		)
	Disposals	—			6			36			42
	Foreign exchange	(1		)	—			(2		)	(3		)
	Depreciation: at December 31, 2013	(36		)	(87		)	(345		)	(468		)
	Depreciation expense provided	(4		)	(20		)	(68		)	(92		)
	Disposals	—			10			28			38
	Foreign exchange	2			4			19			25
	Depreciation: at December 31, 2014	$	(38	)	$	(93	)	$	(366	)	$	(497	)
	Net book value:
	At December 31, 2013	$	53		$	155		$	273		$	481
	At December 31, 2014	$	55		$	152		$	276		$	483
	_________________________________
	(i)	Included within land and buildings are assets held under capital leases: At December 31, 2014, cost and accumulated depreciation were $32 million and $8 million respectively (2013: $31 million and $6 million, respectively; 2012: $25 million and $4 million respectively). Depreciation in the year ended December 31, 2014 was $2 million (2013: $2 million; 2012: $1 million).

Goodwill

Goodwill	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL
	12	GOODWILL
	Goodwill represents the excess of the cost of businesses acquired over the fair value of identifiable net assets at the dates of acquisition. Goodwill is not amortized but is subject to impairment testing annually and whenever facts or circumstances indicate that the carrying amounts may not be recoverable.
	The Company has determined that its reporting units are consistent with its operating segments: North America; International and Global. Goodwill is allocated to these reporting units based on the original purchase price allocation for acquisitions within the reporting units. When a business entity is sold, goodwill is allocated to the disposed entity based on the fair value of that entity compared to the fair value of the reporting unit in which it is included.
	The changes in the carrying amount of goodwill by reporting unit for the years ended December 31, 2014 and 2013, are as follows:
		Global			North			International			Total
					America
		(millions)
	Balance at January 1, 2013
	Goodwill, gross	$	1,127		$	1,792		$	400		$	3,319
	Accumulated impairment losses	—			(492		)	—			(492		)
	Goodwill, net	1,127			1,300			400			2,827
	Purchase price allocation adjustments	—			(1		)	—			(1		)
	Goodwill acquired during the year	15			—			1			16
	Goodwill disposed of during the year	—			(14		)	—			(14		)
	Other movements	—			(1		)	—			(1		)
	Foreign exchange	3			—			8			11
	Balance at December 31, 2013
	Goodwill, gross	1,145			1,776			409			3,330
	Accumulated impairment losses	—			(492		)	—			(492		)
	Goodwill, net	$	1,145		$	1,284		$	409		$	2,838
	Purchase price allocation adjustments	3			3			7			13
	Goodwill acquired during the year	5			—			179			184
	Goodwill disposed of during the year	—			(48		)	—			(48		)
	Other movements (i)	88			(45		)	(43		)	—
	Foreign exchange	(7		)	—			(43		)	(50		)
	Balance at December 31, 2014
	Goodwill, gross	1,234			1,686			509			3,429
	Accumulated impairment losses	—			(492		)	—			(492		)
	Goodwill, net	$	1,234		$	1,194		$	509		$	2,937
	_________________________________
	(i)	Effective January 1, 2014, the Company changed its internal reporting structure: UK Retail, previously reported within the International segment, is now reported within the Global segment; Mexico Retail, which was previously reported within the North America segment, is now reported in the International segment; and the US captive consulting and facultative reinsurance businesses, both previously reported within the North America segment, are now reported within the Global segment. As a consequence of these changes goodwill has been reallocated between reporting units using the relative fair value allocation approach.
	Impairment Review
	The Company reviews goodwill for impairment annually, or whenever events of circumstances indicate impairment may have occurred. In the first step of the impairment test, the fair value of each reporting unit is compared with its carrying value, including goodwill. If the carrying value of a reporting unit exceeds its fair value, the amount of an impairment loss, if any, is calculated in the second step of the impairment test by comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill.
	The Company's goodwill impairment test for 2014 has not resulted in an impairment charge (2013: $nil; 2012: $492 million).
	In 2012, as a consequence of the Company's annual goodwill impairment test performed as of October 1, 2012, the Company concluded that a pre-tax impairment charge of $492 million was required to reduce the carrying value of the goodwill associated with the Company's North America reporting unit from $1,782 million to its implied fair value of $1,290 million. The Company used the income approach to measure the fair value of the North America reporting unit, which involved calculating the fair value of the reporting unit based on the present value of the estimated future cash flows. Cash flow projections were based on management's estimates of revenue growth rates and operating margins, taking into consideration industry and market conditions and the uncertainty related to the business's ability to execute on the projected cash flows. The discount rate used was based on the weighted-average cost of capital adjusted for the relevant risk associated with market participant expectations of characteristics of the reporting unit. The unobservable inputs included projected revenue growth rates, profitability and the market participant assumptions within the discount rate. The decline in the estimated fair value of the reporting unit resulted from lower projected revenue growth rates and profitability levels as well as an increase in the discount rate used to calculate discounted cash flows. As a consequence of the significance of unobservable inputs developed using company-specific information, the re-measurement of goodwill for this reporting unit is classified as a non-recurring level 3 fair value assessment.

Other_Intangible_Assets_Net

Other Intangible Assets, Net	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
OTHER INTANGIBLE ASSETS, NET
	13	OTHER INTANGIBLE ASSETS, NET
	Other intangible assets are classified into the following categories:
	•	Client Relationships
	•	Management Contracts
	•	Other, including:
	•	non-compete agreements
	•	trade names
	•	contract based, technology and other
	The major classes of amortizable intangible assets are as follows:
		31-Dec-14							31-Dec-13
		Gross carrying		Accumulated			Net carrying amount		Gross carrying		Accumulated			Net carrying amount
		amount		amortization					amount		amortization
		(millions)
	Client relationships	$	689	$	(316	)	$	373	$	671	$	(326	)	$	345
	Management contracts	71		(1		)	70		—		—			—
	Other	11		(4		)	7		14		(6		)	8
	Total amortizable intangible assets	$	771	$	(321	)	$	450	$	685	$	(332	)	$	353
	The aggregate amortization of intangible assets for the year ended December 31, 2014 was $54 million (2013: $55 million; 2012: $59 million). The estimated aggregate amortization of intangible assets for each of the next five years ended December 31 is as follows:
		(millions)
	2015	$	57
	2016	51
	2017	46
	2018	41
	2019	37
	Thereafter	218
	Total	$	450

Other_Assets

Other Assets	12 Months Ended
	Dec. 31, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
OTHER ASSETS	An analysis of other assets is as follows:
		December 31,
		2014		2013
		(millions)
	Other current assets
	Prepayments and accrued income	$	81	$	73
	Income taxes receivable	30		32
	Deferred compensation plan assets	17		26
	Other receivables	86		66
	Total other current assets	$	214	$	197
	Other non-current assets
	Deferred compensation plan assets	$	92	$	88
	Income taxes receivable	—		21
	Accounts receivable, net	29		28
	Other investments	29		19
	Other receivables	70		50
	Total other non-current assets	$	220	$	206
	Total other assets	$	434	$	403

Other_Liabilities

Other Liabilities	12 Months Ended
	Dec. 31, 2014
Other Liabilities Disclosure [Abstract]
OTHER LIABILITIES
	15	OTHER LIABILITIES
	An analysis of other liabilities is as follows:
		December 31,
		2014		2013
		(millions)
	Other current liabilities
	Accounts payable	$	131	$	123
	Accrued dividends payable	55		51
	Other taxes payable	44		51
	Deferred compensation plan liability	17		26
	Other payables	197		164
	Total other current liabilities	$	444	$	415
	Other non-current liabilities
	Incentives from lessors	$	171	$	183
	Deferred compensation plan liability	92		89
	Contingent or deferred consideration on acquisition	26		13
	Accounts payable	14		6
	Income taxes payable	15		40
	Other payables	71		43
	Total other non-current liabilities	$	389	$	374
	Total other liabilities	$	833	$	789

Allowance_for_Doubtful_Account

Allowance for Doubtful Accounts	12 Months Ended
	Dec. 31, 2014
Allowance for Doubtful Accounts [Abstract]
ALLOWANCE FOR DOUBTFUL ACCOUNTS
	16	ALLOWANCE FOR DOUBTFUL ACCOUNTS
	Accounts receivable are stated at estimated net realizable values. The allowances shown below as at the end of each period, are recorded as the amounts considered by management to be sufficient to meet probable future losses related to uncollectible accounts.
		Balance at		Additions/		Deductions			Foreign		Balance at
		beginning of year		(releases)		/ Other movements			exchange differences		end of year
				charged to
				costs and expenses
	Description
		(millions)
	Year Ended December 31, 2014
	Allowance for doubtful accounts	$	13	$	4	$	(6	)	$	1	$	12
	Year Ended December 31, 2013
	Allowance for doubtful accounts	$	14	$	3	$	(4	)	$	—	$	13
	Year Ended December 31, 2012
	Allowance for doubtful accounts	$	13	$	16	$	(15	)	$	—	$	14

Pension_Plans

Pension Plans	12 Months Ended
	Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Pension Plans
	17	PENSION PLANS
	The Company maintains two principal defined benefit pension plans that cover approximately half of the Company's employees in the United States and United Kingdom. Both of these plans are now closed to new entrants and with effect from May 15, 2009, the Company closed the US defined benefit plan to future accrual. New employees in the United Kingdom are offered the opportunity to join a defined contribution plan and in the United States are offered the opportunity to join a 401(k) plan. In addition to the Company’s UK and US defined benefit pension plans, the Company has several smaller defined benefit pension plans in certain other countries in which it operates including a US non-qualified plan and an unfunded plan in the UK. Elsewhere, pension benefits are typically provided through defined contribution plans. It is the Company’s policy to fund pension costs as required by applicable laws and regulations.
	At December 31, 2014, the Company recorded, on the Consolidated Balance Sheets:
	•	a pension benefit asset of $314 million (2013: $278 million) representing:
	•	$314 million (2013: $276 million) in respect of the UK defined benefit pension plan; and
	•	$nil (2013: $2 million) in respect of the international defined benefit pension plans.
	•	a total liability for pension benefits of $284 million (2013: $136 million) representing:
	•	$245 million (2013: $107 million) in respect of the US defined benefit pension plan; and
	•	$39 million (2013: $29 million) in respect of the international, US non-qualified and UK unfunded defined benefit pension plans.
	UK and US defined benefit plans
	The following schedules provide information concerning the Company’s UK and US defined benefit pension plans as of and for the years ended December 31:
		UK Pension Benefits								US Pension Benefits
		2014				2013				2014				2013
		(millions)
	Change in benefit obligation:
	Benefit obligation, beginning of year	$	2,785			$	2,582			$	864			$	958
	Service cost	41				37				—				—
	Interest cost	121				109				40				38
	Employee contributions	2				2				—				—
	Actuarial loss (gain)	390				79				183				(81		)
	Curtailment gain	(2		)		—				—				—
	Benefits paid	(85		)		(78		)		(36		)		(51		)
	Foreign currency changes	(168		)		54				—				—
	Benefit obligations, end of year	3,084				2,785				1,051				864
	Change in plan assets:
	Fair value of plan assets, beginning of year	3,061				2,716				757				708
	Actual return on plan assets	520				255				65				60
	Employee contributions	2				2				—				—
	Employer contributions	91				100				20				40
	Benefits paid	(85		)		(78		)		(36		)		(51		)
	Foreign currency changes	(191		)		66				—				—
	Fair value of plan assets, end of year	3,398				3,061				806				757
	Funded status at end of year	$	314			$	276			$	(245	)		$	(107	)
	Components on the Consolidated Balance Sheets:
	Pension benefits asset	$	314			$	276			$	—			$	—
	Liability for pension benefits	—				—				(245		)		(107		)
	Amounts recognized in accumulated other comprehensive loss consist of:
		UK Pension Benefits								US Pension Benefits
		2014				2013				2014				2013
						(millions)
	Net actuarial loss	$	809			$	815			$	399			$	233
	Prior service gain	(20		)		(24		)		—				—
	The accumulated benefit obligations for the Company’s UK and US defined benefit pension plans were $3,017 million and $1,051 million, respectively (2013: $2,701 million and $864 million, respectively).
	The components of the net periodic benefit (income) cost and other amounts recognized in other comprehensive loss for the UK and US defined benefit plans are as follows:
		Years ended December 31,
		UK Pension Benefits												US Pension Benefits
		2014				2013				2012				2014				2013			2012
										(millions)
	Components of net periodic benefit (income) cost:
	Service cost	$	41			$	37			$	35			$	—			$	—		$	—
	Interest cost	121				109				108				40				38			41
	Expected return on plan assets	(213		)		(191		)		(181		)		(54		)		(51		)	(46		)
	Amortization of unrecognized prior service gain and curtailment gain	(4		)		(5		)		(6		)		—				—			—
	Amortization of unrecognized actuarial loss	42				45				39				6				9			8
	Net periodic benefit (income) cost	$	(13	)		$	(5	)		$	(5	)		$	(8	)		$	(4	)	$	3
	Other changes in plan assets and benefit obligations recognized in other comprehensive income (loss):
	Net actuarial loss (gain)	$	83			$	15			$	141			$	172			$	(90	)	$	37
	Amortization of unrecognized actuarial loss	(42		)		(45		)		(39		)		(6		)		(9		)	(8		)
	Amortization of unrecognized prior service gain and curtailment gain	4				5				6				—				—			—
	Curtailment gain	(2		)		—				—				—				—			—
	Total recognized in other comprehensive income (loss)	$	43			$	(25	)		$	108			$	166			$	(99	)	$	29
	Total recognized in net periodic benefit cost and other comprehensive income (loss)	$	30			$	(30	)		$	103			$	158			$	(103	)	$	32
	The estimated net loss and prior service cost for the UK and US defined benefit plans that will be amortized from accumulated other comprehensive loss into net periodic benefit cost over the next fiscal year are:
	UK Pension				US Pension
	Benefits				Benefits
	(millions)
Estimated net loss	$	39			$	11
Prior service gain	(3		)		—
The following schedule provides other information concerning the Company’s UK and US defined benefit pension plans:
	Years ended December 31,
	UK Pension Benefits						US Pension Benefits
	2014			2013			2014			2013
Weighted-average assumptions to determine benefit obligations:
Discount rate	3.6	%		4.4	%		3.9	%		4.8	%
Rate of compensation increase	2.9	%		3.2	%		N/A			N/A
Weighted-average assumptions to determine net periodic benefit cost:
Discount rate	4.4	%		4.4	%		4.8	%		4.1	%
Expected return on plan assets	7	%		7.3	%		7.3	%		7.3	%
Rate of compensation increase	3.2	%		2.3	%		N/A			N/A
The expected return on plan assets was determined on the basis of the weighted-average of the expected future returns of the various asset classes, using the target allocations shown below. The expected returns on UK plan assets are: UK and foreign equities 8.86 percent, debt securities 4.38 percent, hedge funds 8.38 percent and real estate 6.53 percent. The expected returns on US plan assets are: US and foreign equities 11.0 percent and debt securities 3.6 percent.
The Company’s pension plan asset allocations based on fair values were as follows:
		Years ended December 31,
		UK Pension Benefits						US Pension Benefits
Asset Category		2014			2013			2014			2013
Equity securities		34	%		36	%		48	%		52	%
Debt securities		45	%		38	%		49	%		46	%
Hedge funds		14	%		17	%		—	%		—	%
Real estate		3	%		3	%		—	%		—	%
Cash		4	%		6	%		—	%		—	%
Other		—	%		—	%		3	%		2	%
Total		100	%		100	%		100	%		100	%
In the United Kingdom, the pension trustees, in consultation with the Company, maintain a diversified asset portfolio and this together with contributions made by the Company is expected to meet the pension scheme’s liabilities as they become due. The UK plan’s assets are divided into 13 separate portfolios according to asset class and managed by 10 investment managers. The broad target allocations are UK and foreign equities (36.5 percent), debt securities (43.5 percent), hedge funds (15 percent) and real estate (5 percent). In the United States, the Company’s investment policy is to maintain a diversified asset portfolio, which together with contributions made by the Company is expected to meet the pension scheme’s liabilities as they become due. The US plan’s assets are currently invested in 18 funds representing most standard equity and debt security classes. The broad target allocations are US and foreign equities (50 percent) and debt securities (50 percent).
Fair Value Hierarchy
The fair value hierarchy has three levels based on the reliability of the inputs used to determine fair value:
•	Level 1: refers to fair values determined based on quoted market prices in active markets for identical assets;
•	Level 2: refers to fair values estimated using observable market based inputs or unobservable inputs that are corroborated by market data; and
•	Level 3: includes fair values estimated using unobservable inputs that are not corroborated by market data.
The following tables present, at December 31, 2014 and 2013, for each of the fair value hierarchy levels, the Company’s UK pension plan assets that are measured at fair value on a recurring basis.
		UK Pension Plan
31-Dec-14		Level 1				Level 2				Level 3				Total
						(millions)
Equity securities:
US equities		$	565			$	185			$	—			$	750
UK equities		234				15				—				249
Other equities		26				124				—				150
Fixed income securities:
US Government bonds		81				2				—				83
UK Government bonds		783				6				—				789
Other Government bonds		3				3				99				105
UK corporate bonds		—				103				—				103
Other corporate bonds		113				33				—				146
Derivatives		—				293				—				293
Real estate		—				—				124				124
Cash and cash equivalents		124				13				—				137
Other investments:
Hedge funds		—				—				487				487
Other		—				(18		)		—				(18		)
Total		$	1,929			$	759			$	710			$	3,398
		UK Pension Plan
31-Dec-13		Level 1				Level 2				Level 3				Total
						(millions)
Equity securities:
US equities		$	659			$	81			$	—			$	740
UK equities		239				17				—				256
Other equities		40				63				—				103
Fixed income securities:
US Government bonds		31				—				—				31
UK Government bonds		656				—				—				656
Other Government bonds		7				—				100				107
UK corporate bonds		75				—				—				75
Other corporate bonds		151				—				—				151
Derivatives		—				154				—				154
Real estate		—				—				92				92
Cash and cash equivalents		163				—				—				163
Other investments:
Hedge funds		—				28				477				505
Other		—				28				—				28
Total		$	2,021			$	371			$	669			$	3,061
The UK plan’s real estate investment comprises UK property and infrastructure investments which are valued by the fund manager taking into account cost, independent appraisals and market based comparable data. The UK plan’s hedge fund investments are primarily invested in various ‘fund of funds’ and are valued based on net asset values calculated by the fund and are not publicly available. Liquidity is typically monthly and is subject to liquidity of the underlying funds. The UK plan’s Other Government Bonds investments are primarily invested in investment-grade emerging and developed market government bonds. Funds are valued on a net asset value basis, with the underlying bond instruments being valued using bid-side, clean pricing from approved pricing vendors. Prices are not publicly available.
The following tables present, at December 31, 2014 and 2013, for each of the fair value hierarchy levels, the Company’s US pension plan assets that are measured at fair value on a recurring basis.
		US Pension Plan
31-Dec-14		Level 1				Level 2				Level 3				Total
						(millions)
Equity securities:
US equities		$	115			$	117			$	—			$	232
Non US equities		110				44				—				154
Fixed income securities:
US Government bonds		—				72				—				72
US corporate bonds		—				171				—				171
International fixed income securities		59				42				—				101
Municipal & Non US government bonds		—				32				—				32
Other investments:
Mortgage backed securities		—				16				—				16
Other		20				8				—				28
Total		$	304			$	502			$	—			$	806
		US Pension Plan
31-Dec-13		Level 1				Level 2				Level 3				Total
						(millions)
Equity securities:
US equities		$	120			$	125			$	—			$	245
Non US equities		116				33				—				149
Fixed income securities:
US Government bonds		—				55				—				55
US corporate bonds		—				151				—				151
International fixed income securities		58				42				—				100
Municipal & Non US government bonds		—				30				—				30
Other investments:
Mortgage backed securities		—				12				—				12
Other		9				6				—				15
Total		$	303			$	454			$	—			$	757
Equity securities comprise:
•	ordinary shares and preferred shares which are valued using quoted market prices; and
•	pooled investment vehicles which are valued at their net asset values as calculated by the investment manager and typically have daily or weekly liquidity.
Fixed income securities comprise US, UK and other Government Treasury Bills, loan stock, index linked loan stock and UK and other corporate bonds which are typically valued using quoted market prices. Certain of these investments are classified as Level 2 investments on the basis that the assets are valued at their net asset values calculated by the investment manager and liquidity is not daily.
Level 3 investments
As a result of the inherent limitations related to the valuations of the Level 3 investments, due to the unobservable inputs of the underlying funds, the estimated fair value may differ significantly from the values that would have been used had a market for those investments existed.
The following table summarizes the changes in the UK pension plan’s Level 3 assets for the years ended December 31, 2014 and 2013:
	UK Pension
	Plan
	Level 3
	(millions)
Balance at January 1, 2013	$	507
Purchases, sales, issuances and settlements, net	121
Unrealized and realized gains relating to instruments still held at end of year	29
Foreign exchange	12
Balance at December 31, 2013	$	669
Purchases, sales, issuances and settlements, net	40
Unrealized and realized gains relating to instruments still held at end of year	24
Foreign exchange	(23		)
Balance at December 31, 2014	$	710
In 2015, the Company expects to make contributions to the UK plan of approximately $96 million and $10 million to the US plan. In addition, approximately $10 million will be paid in 2015 into the UK defined benefit plan related to employee's salary sacrifice contributions.
The following benefit payments, which reflect expected future service, as appropriate, are estimated to be paid by the UK and US defined benefit pension plans:
Expected future benefit payments		UK Pension Benefits			US Pension Benefits
		(millions)
2015		83			41
2016		84			43
2017		87			46
2018		89			49
2019		92			51
2019-2023		505			284
Willis North America has a 401(k) plan covering all eligible employees of Willis North America and its subsidiaries. The plan allows participants to make pre-tax contributions which the Company, at its discretion may match. The Company did not make any matching contributions in any year presented other than for former HRH employees whose contributions were matched up to 75 percent under the terms of the acquisition. All investment assets of the plan are held in a trust account administered by independent trustees. The Company’s 401(k) matching contributions for 2014 were $15 million (2013: $15 million; 2012: $10 million), matching contributions were increased 1 percent during 2013.
Other defined benefit pension plans
In addition to the Company’s UK and US defined benefit pension plans, the Company has several smaller defined benefit pension plans in certain other countries in which it operates together with a non-qualified defined benefit pension plan in the United States and an unfunded defined benefit pension plan in the United Kingdom.
For disclosure purposes these smaller additional US and UK plans are combined with the Company's other defined benefit pension plans in the tables below.
In total, a $39 million net pension benefit liability (2013: $27 million) has been recognized in respect of these other schemes.
The following schedules provide information concerning the Company’s international, US non-qualified and UK unfunded defined benefit pension plans:
	Other defined benefit plans
	2014				2013
	(millions)
Change in benefit obligation:
Benefit obligation, beginning of year	$	195			$	180
Service cost	3				3
Interest cost	7				7
Actuarial loss (gain)	38				(5		)
Benefits paid	(9		)		(6		)
Reclassification from other non-current liabilities (i)	—				10
Foreign currency changes	(24		)		6
Benefit obligations, end of year	210				195
Change in plan assets:
Fair value of plan assets, beginning of year	168				150
Actual return on plan assets	25				9
Employer contributions	11				10
Benefits paid	(9		)		(6		)
Foreign currency changes	(24		)		5
Fair value of plan assets, end of year	171				168
Funded status at end of year	$	(39	)		$	(27	)
Components on the Consolidated Balance Sheets:
Pension benefits asset	$	—			$	2
Liability for pension benefits	$	(39	)		$	(29	)
_________________________________
(i)	Represents the transfer in of the benefit obligation for UK unfunded plan from non-current other liabilities.
Amounts recognized in accumulated other comprehensive loss consist of a net actuarial loss of $42 million (2013: $27 million).
The accumulated benefit obligation for the Company’s other defined benefit pension plans was $203 million (2013: $191 million).
The components of the net periodic benefit cost and other amounts recognized in other comprehensive loss for the other defined benefit pension plans are as follows:
	Other defined benefit plans
	2014				2013				2012
	(millions)
Components of net periodic benefit cost:
Service cost	$	3			$	3			$	3
Interest cost	7				7				7
Expected return on plan assets	(6		)		(6		)		(6		)
Amortization of unrecognized actuarial loss	—				1				—
Net periodic benefit cost	$	4			$	5			$	4
Other changes in plan assets and benefit obligations recognized in other comprehensive income (loss):
Amortization of unrecognized actuarial loss	$	—			$	(1	)		$	—
Net actuarial loss (gain)	19				(8		)		25
Total recognized in other comprehensive loss (income)	19				(9		)		25
Total recognized in net periodic benefit cost and other comprehensive loss (income)	$	23			$	(4	)		$	29
The estimated net loss for the other defined benefit pension plans that will be amortized from accumulated other comprehensive loss into net periodic benefit cost over the next fiscal year is $1 million.
The following schedule provides other information concerning the Company’s other defined benefit pension plans:
	Other defined benefit plans
	2014		2013
Weighted-average assumptions to determine benefit obligations:
Discount rate	2.00% - 3.60%		3.30% - 4.40%
Rate of compensation increase	2.00% - 3.50%		2.00% - 2.50%
Weighted-average assumptions to determine net periodic benefit cost:
Discount rate	3.30% - 4.40%		2.50% - 4.40%
Expected return on plan assets	2.00% - 4.66%		2.00% - 4.66%
Rate of compensation increase	2.00% - 2.50%		2.00% - 2.50%
The determination of the expected long-term rate of return on the other defined benefit plan assets is dependent upon the specific circumstances of each individual plan. The assessment may include analyzing historical investment performance, investment community forecasts and current market conditions to develop expected returns for each asset class used by the plans.
The Company’s other defined benefit pension plan asset allocations at December 31, 2014 based on fair values were as follows:
		Other defined benefit plans
Asset Category		2014			2013
Equity securities		24	%		35	%
Debt securities		40	%		39	%
Real estate		3	%		3	%
Derivatives		13	%		14	%
Other		20	%		9	%
Total		100	%		100	%
The investment policies for the international plans vary by jurisdiction but are typically established by the local pension plan trustees, where applicable, and seek to maintain the plans’ ability to meet liabilities of the plans as they fall due and to comply with local minimum funding requirements.
Fair Value Hierarchy
The following tables present, at December 31, 2014 and 2013, for each of the fair value hierarchy levels, the Company’s other defined benefit pension plan assets that are measured at fair value on a recurring basis.
		Other defined benefit plans
31-Dec-14		Level 1				Level 2				Level 3				Total
						(millions)
Equity securities:
US equities		$	18			$	—			$	—			$	18
UK equities		4				—				—				4
Overseas equities		18				—				—				18
Fixed income securities:
Other Government bonds		65				—				—				65
Corporate bonds		4				—				—				4
Derivative instruments		—				23				—				23
Real estate		—				—				6				6
Cash		11				—				—				11
Other investments:
Other investments		14				—				8				22
Total		$	134			$	23			$	14			$	171
		Other defined benefit plans
31-Dec-13		Level 1				Level 2				Level 3				Total
						(millions)
Equity securities:
US equities		$	29			$	—			$	—			$	29
UK equities		5				—				—				5
Overseas equities		26				—				—				26
Fixed income securities:
Other Government bonds		61				—				—				61
Corporate bonds		4				—				—				4
Derivative instruments		—				23				—				23
Real estate		—				—				5				5
Cash		8				—				—				8
Other investments:
Other investments		—				—				7				7
Total		$	133			$	23			$	12			$	168
Equity securities comprise:
ordinary shares which are valued using quoted market prices; and
•	unit linked funds which are valued at their net asset values as calculated by the investment manager and typically have daily liquidity.
Fixed income securities include overseas Government bonds which are typically valued using quoted market prices and derivative instruments which are valued using an income approach typically using swap curves as an input.
Real estate investment comprises overseas property and infrastructure investments which are valued by fund managers taking into account cost, independent appraisals and market based comparable data.
Assets classified as Level 3 investments did not materially change during the year ended December 31, 2014.
In 2015, the Company expects to contribute $10 million to the other defined benefit pension plans.
The following benefit payments, which reflect expected future service, as appropriate, are estimated to be paid by the other defined benefit pension plans:
		Other defined benefit plans
		Pension
Expected future benefit payments		Benefits
		(millions)
2015		$	5
2016		6
2017		6
2018		6
2019		6
2019-2023		32

Debt

Debt	12 Months Ended
	Dec. 31, 2014
Debt Disclosure [Abstract]
Debt
	18	DEBT
	Current portion of long-term debt consists of the following:
		December 31,
		2014		2013
		(millions)
	Current portion of 7-year term loan facility expires 2018	$	17	$	15
	5.625% senior notes due 2015	148		—
	Fair value adjustment on 5.625% senior notes due 2015	1		—
	3-year term loan facility expires 2015	1		—
		$	167	$	15
	Long-term debt consists of the following:
		December 31,
		2014		2013
		(millions)
	7-year term loan facility expires 2018	$	242	$	259
	5.625% senior notes due 2015	—		148
	Fair value adjustment on 5.625% senior notes due 2015	—		4
	4.125% senior notes due 2016	299		299
	6.200% senior notes due 2017	394		394
	7.000% senior notes due 2019	187		187
	5.750% senior notes due 2021	497		496
	4.625% senior notes due 2023	249		249
	6.125% senior notes due 2043	274		274
	3-year term loan facility expires 2015	—		1
		$	2,142	$	2,311
	Guarantees
	All direct obligations under the 5.625%, 6.200% and 7.000% senior notes are guaranteed by Willis Group Holdings, Willis Netherlands B.V., Willis Investment UK Holdings Limited, TA I Limited, Trinity Acquisition Limited and Willis Group Limited.
	All direct obligations under the 4.625% and 6.125% senior notes are guaranteed by Willis Group Holdings, Willis Netherlands Holdings B.V., Willis Investment UK Holdings Limited, TA I Limited, Willis North America Inc. and Willis Group Limited.
	All direct obligations under the 4.125% and 5.750% senior notes are guaranteed by Trinity Acquisition Limited, Willis Netherlands Holdings B.V., Willis Investment UK Holdings Limited, TA I Limited, Willis North America Inc. and Willis Group Limited.
	Term loans and revolving credit facilities
	On July 23, 2013 the Company entered into an amendment to its existing credit facilities to extend both the amount of financing and the maturity date of the facilities. As a result of this amendment, the Company's revolving credit facility was increased from $500 million to $800 million. The maturity date on both the revolving credit facility and the $300 million term loan was extended to July 23, 2018, from December 16, 2016, respectively. At the amendment date the Company owed $281 million on the term loan and there was no change to this amount as a result of the refinancing.
	The 7-year term loan facility expiring 2018 bears interest at LIBOR plus 1.50% and is repayable in quarterly installments and a final repayment of $186 million is due in the third quarter of 2018. In 2014, the Company made $15 million of mandatory repayments against this 7-year term loan. Drawings under the $800 million revolving credit facility bear interest at LIBOR plus 1.50%. These margins apply while the Company’s debt rating remains BBB-/Baa3. As of December 31, 2014 $nil was outstanding under this revolving credit facility (December 31, 2013: $nil).
	The agreements relating to the Company's 7-year term loan facility expiring 2018 and the revolving $800 million credit facility contain requirements to maintain maximum levels of consolidated funded indebtedness in relation to consolidated EBITDA and minimum level of consolidated EBITDA to consolidated cash interest expense, subject to certain adjustments. In addition, the agreements relating to the Company's credit facilities and senior notes include, in the aggregate covenants relating to the delivery of financial statements, reports and notices, limitations on liens, limitations on sales and other disposals of assets, limitations on indebtedness and other liabilities, limitations on sale and leaseback transactions, limitations on mergers and other fundamental changes, maintenance of property, maintenance of insurance, nature of business, compliance with applicable laws, maintenance of corporate existence and rights, payment of taxes and access to information and properties. At December 31, 2014, the Company was in compliance with all covenants.
	On March 3, 2014, Willis Securities, Inc., a wholly-owned indirect subsidiary of Willis Group Holdings plc, entered into a $300 million revolving note and cash subordination agreement available for drawing from March 3, 2014 through March 3, 2015.
	The aggregate unpaid principal amount of all advances is repayable on or before March 3, 2016.
	On April 28, 2014, the Company entered into an amendment to the $300 million revolving note and cash subordination
	agreement to increase the amount of financing and to extend both the end date of the original credit period and the original
	repayment date. As a result of this amendment, the revolving credit facility was increased from $300 million to $400 million.
	The end date of the credit period was extended to April 28, 2015 from March 3, 2015 and the repayment date was extended to
	April 28, 2016 from March 3, 2016. As of December 31, 2014 $nil was outstanding under this revolving credit facility.
	Proceeds under the credit facility will be used for regulatory capital purposes related to securities underwriting only, which will
	allow Willis Securities to meet or exceed capital requirements of regulatory agencies, self-regulatory agencies and their clearing
	houses, including the Financial Industry Regulatory Authority. Advances under the credit facility bear interest at a rate
	equal to (a) for Eurocurrency Loans, LIBOR plus 1.50% to 2.25%, and (b) for base rates Loans, the highest of (i) the Federal
	Funds rates plus 0.5%, (ii) the 'prime rate' as announced by SunTrust Bank, and (iii) LIBOR plus 1.00%, plus 0.5% to 1.25%, in
	each case, based upon the Company’s guaranteed senior-unsecured long-term debt rating.
	Senior Notes
	On August 15, 2013 the Company issued $250 million of 4.625% senior notes due 2023 and $275 million of 6.125% senior notes due 2043. The effective interest rates of these senior notes are 4.696% and 6.154%, respectively, which include the impact of the discount upon issuance.
	On July 25, 2013 the Company commenced an offer to purchase for cash any and all of its 5.625% senior notes due 2015 and a portion of its 6.200% senior notes due 2017 and its 7.000% senior notes due 2019 for an aggregate purchase price of up to $525 million. On August 22, 2013 the proceeds from the issue of the senior notes due 2023 and 2043 were used to fund the purchase of $202 million of 5.625% senior notes due 2015, $206 million of 6.200% senior notes due 2017 and $113 million of 7.000% senior notes due 2019.
	The Company incurred total losses on extinguishment of debt of $60 million during the year ended December 31, 2013. This was made up of a tender premium of $65 million, the write-off of unamortized debt issuance costs of $2 million and a credit for the reduction of the fair value adjustment on 5.625% senior notes due 2015 of $7 million.
	Lines of credit
	The Company also has available $3 million (2013: $4 million) in lines of credit, of which $1 million was drawn as of December 31, 2014 (2013: $nil).
	Analysis of interest expense
	The following table shows an analysis of the interest expense for the years ended December 31:
		Year ended December 31,
		2014		2013		2012
		(millions)
	5.625% senior notes due 2015	$	8	$	12	$	12
	4.125% senior notes due 2016	13		13		13
	6.200% senior notes due 2017	25		33		38
	7.000% senior notes due 2019	14		18		21
	5.750% senior notes due 2021	30		29		29
	4.625% senior notes due 2023	11		4		—
6.125% senior notes due 2043	16		6		—
7-year term loan facility expires 2018	5		6		6
Revolving $800 million credit facility	3		2		1
Revolving $400 million credit facility	4		—		—
Other	6		3		8
Total interest expense	$	135	$	126	$	128

Provisions_for_Liabilities

Provisions for Liabilities	12 Months Ended
	Dec. 31, 2014
Provisions for Liabilities [Abstract]
PROVISIONS FOR LIABILITIES
	19	PROVISIONS FOR LIABILITIES
	An analysis of movements on provisions for liabilities is as follows:
		Claims,			Other			Total
		lawsuits and			provisions(ii)
		other
		proceedings(i)
					(millions)
	Balance at January 1, 2013	$	152		$	28		$	180
	Net provisions made during the year	28			6			34
	Balances transferred in during the year (iii)	—			13			13
	Utilized in the year	(17		)	(6		)	(23		)
	Foreign currency translation adjustment	1			1			2
	Balance at December 31, 2013	$	164		$	42		$	206
	Net provisions made during the year	19			5			24
	Balances transferred in during the year (iv)	—			5			5
	Utilized in the year	(31		)	(3		)	(34		)
	Foreign currency translation adjustment	(4		)	(3		)	(7		)
	Balance at December 31, 2014	$	148		$	46		$	194
	_________________________________
	(i)	The claims, lawsuits and other proceedings provision includes E&O cases which represents management’s assessment of liabilities that may arise from asserted and unasserted claims for alleged errors and omissions that arise in the ordinary course of the Group’s business. Where some of the potential liability is recoverable under the Group’s external insurance arrangements, the full assessment of the liability is included in the provision with the associated insurance recovery shown separately as an asset.
	(ii)	The ‘Other’ category includes amounts relating to vacant property provisions of $4 million (2013: $10 million).
	(iii)	Provisions held in the UK for ongoing post placement services, long term disability and legal claims all previously recognized within Deferred Revenue and Accrued Expenses were transferred to Provisions for Liabilities during 2013.
	(iv)	Provisions held in the UK for dilapidation on UK properties all previously recognized within Deferred Revenue and Accrued Expenses were transferred to Provisions for Liabilities during 2014.

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES
	20	COMMITMENTS AND CONTINGENCIES
	The Company’s contractual obligations as at December 31, 2014 are presented below:
		Payments due by
	Obligations (iii)	Total		2015			2016-2017		2018-2019		After 2019
		(millions)
	7-year term loan facility expires 2018	$	259	$	17		$	45	$	197	$	—
	Interest on term loan	14		4			8		2		—
	Revolving $800 million credit facility commitment fees	7		2			4		1		—
	Revolving $400 million credit facility commitment fees	2		1			1		—		—
	5.625% senior notes due 2015	148		148			—		—		—
	4.125% senior notes due 2016	300		—			300		—		—
	6.200% senior notes due 2017	394		—			394		—		—
	7.000% senior notes due 2019	187		—			—		187		—
	5.750% senior notes due 2021	500		—			—		—		500
	4.625% senior notes due 2023	250		—			—		—		250
	6.125% senior notes due 2043	275		—			—		—		275
	Interest on senior notes	896		112			173		137		474
	Total debt and related interest	3,232		284			925		524		1,499
	Operating leases(i)	1,181		128			221		175		657
	Pensions	346		116			190		40		—
	Other contractual obligations(ii)	143		10			40		43		50
	Acquisition liabilities	51		8			27		16		—
	Total contractual obligations	$	4,953	$	546		$	1,403	$	798	$	2,206
	_________________________________
	(i)	Presented gross of sublease income.
	(ii)	Other contractual obligations include capital lease commitments, put option obligations and investment fund capital call obligations, the timing of which are included at the earliest point they may fall due.
	(iii)	The above excludes $19 million of liabilities for unrecognized tax benefits as the Company is unable to reasonably predict the timing of settlement of these liabilities.
	Debt obligations and facilities
	The Company’s debt and related interest obligations at December 31, 2014 are shown in the above table.
	Mandatory repayments of debt over the next 12 months include expiration of the 3-year term loan facility expiring 2015, maturity of the 5.625% senior notes due 2015 and the scheduled repayment of the current portion of the Company’s 7-year term loan. The Company also has the right, at its option, to prepay indebtedness under the credit facility without further penalty and to redeem the senior notes by paying a ‘make-whole’ premium as provided under the applicable debt instrument.
	Operating leases
	The Company leases certain land, buildings and equipment under various operating lease arrangements. Original non-cancellable lease terms typically are between 10 and 20 years and may contain escalation clauses, along with options that permit early withdrawal. The total amount of the minimum rent is expensed on a straight-line basis over the term of the lease.
	As of December 31, 2014, the aggregate future minimum rental commitments under all non-cancellable operating lease agreements are as follows:
		Gross rental		Rentals from			Net rental
		commitments		subleases			commitments
				(millions)
	2015	$	128	$	(13	)	$	115
	2016	115		(13		)	102
	2017	106		(12		)	94
	2018	91		(7		)	84
	2019	84		(5		)	79
	Thereafter	657		(10		)	647
	Total	$	1,181	$	(60	)	$	1,121
	The Company leases its main London building under a 25-year operating lease, which expires in 2032. The Company’s contractual obligations in relation to this commitment included in the table above total $645 million (2013: $719 million). Annual rentals are $36 million (2013: $36 million) per year and the Company has subleased approximately 29 percent (2013: 29 percent) of the premises under leases up to 15 years. The amounts receivable from subleases, included in the table above, total $51 million (2013: $66 million; 2012: $76 million).
	Rent expense amounted to $134 million for the year ended December 31, 2014 (2013: $141 million; 2012: $135 million). The Company’s rental income from subleases was $13 million for the year ended December 31, 2014 (2013: $15 million; 2012: $17 million).
	Pensions
	Contractual obligations for the Company's pension plans reflect the contributions the Company expects to make over the next five years into the US, UK and Other defined benefit plans. These contributions are based on current funding positions and may increase or decrease dependent on the future performance of the plans.
	In the United Kingdom, the Company is required to agree a funding strategy for the UK defined benefit plan with the plan's trustees. In March 2012, the Company agreed to a revised schedule of contributions towards on-going accrual of benefits and deficit funding contributions the Company will make to the UK plan over the six years ended December 31, 2017. Contributions in each of the next three years would total approximately $75 million, of which approximately $19 million relates to on-going contributions calculated as 15.9 percent of active plan members' pensionable salary and approximately $56 million that relates to contributions towards the funding deficit.
	In addition, based on this agreement, further contributions would be payable based on a profit share calculation (equal to 20 percent of EBITDA in excess of $900 million per annum as defined by the revised schedule of contributions) and an exceptional return calculation (equal to 10 percent of any exceptional returns made to shareholders, for example, share buybacks, and special dividends). The Company expects to make an exceptional return contribution of $21 million during 2015 as a result of share buyback activity during 2014. Aggregate contributions under the deficit funding contribution and the profit share calculation are capped at £312 million ($486 million) over the six years ended December 31, 2017.
	We are currently negotiating a new funding arrangement which we are required to do every three years, which may further change the contributions we are required to make during 2015 and beyond.
	An additional amount of approximately $10 million will be paid annually into the UK defined benefit plan related to employee's salary sacrifice contributions.
	The total contracted contributions for all plans in 2015 are expected to be approximately $116 million, excluding approximately $10 million in respect of the salary sacrifice contributions.
	Guarantees
	Guarantees issued by certain of Willis Group Holdings’ subsidiaries with respect to the senior notes and revolving credit facilities are discussed in Note 18 — Debt.
	Certain of Willis Group Holdings’ subsidiaries have given the landlords of some leasehold properties occupied by the Company in the United Kingdom and the United States guarantees in respect of the performance of the lease obligations of the subsidiary holding the lease. The operating lease obligations subject to such guarantees amounted to $756 million and $828 million at December 31, 2014 and 2013, respectively. The capital lease obligations subject to such guarantees amounted to $11 million as at December 31, 2014 (2013: $11 million).
	In addition, the Company has given guarantees to bankers and other third parties relating principally to letters of credit amounting to $20 million and $11 million at December 31, 2014 and 2013, respectively. Willis Group Holdings also guarantees certain of its UK and Irish subsidiaries’ obligations to fund the UK and Irish defined benefit plans.
	Other contractual obligations
	For certain subsidiaries and associates, the Company has the right to purchase shares (a call option) from co-shareholders at various dates in the future. In addition, the co-shareholders of certain subsidiaries and associates have the right to sell their shares (a put option) to the Company at various dates in the future. Generally, the exercise price of such put options and call options is formula-based (using revenues and earnings) and is designed to reflect fair value. Based on current projections of profitability and exchange rates and assuming the put options are exercised, the potential amount payable from these options is not expected to exceed $72 million (2013: $12 million).
	In July 2010, the Company made a capital commitment of $25 million to Trident V Parallel Fund, LP, an investment fund managed by Stone Point Capital. This replaced a capital commitment of $25 million that had been made to Trident V, LP in December 2009. As at December 31, 2014 there have been approximately $22 million of capital contributions.
	In May 2011, the Company made a capital commitment of $10 million to Dowling Capital Partners I, LP. As at December 31, 2014 there had been approximately $7 million of capital contributions.
	Other contractual obligations at December 31, 2014, also include certain capital lease obligations totaling $64 million (2013: $63 million), primarily in respect of the Company's Nashville property.
	Claims, Lawsuits and Other Proceedings
	In the ordinary course of business, the Company is subject to various actual and potential claims, lawsuits, and other
proceedings relating principally to alleged errors and omissions in connection with the placement of insurance and reinsurance.
Similar to other corporations, the Company is also subject to a variety of other claims, including those relating to the
Company’s employment practices. Some of the claims, lawsuits and other proceedings seek damages in amounts which could,
if assessed, be significant.
The material actual or potential claims, lawsuits, and other proceedings, of which the Company is currently aware, are as follows:
Stanford Financial Group Litigation
The Company has been named as a defendant in 13 similar lawsuits relating to the collapse of The Stanford Financial Group (‘Stanford’), for which Willis of Colorado, Inc. acted as broker of record on certain lines of insurance. The complaints in these actions generally allege that the defendants actively and materially aided Stanford’s alleged fraud by providing Stanford with certain letters regarding coverage that they knew would be used to help retain or attract actual or prospective Stanford client investors. The complaints further allege that these letters, which contain statements about Stanford and the insurance policies that the defendants placed for Stanford, contained untruths and omitted material facts and were drafted in this manner to help Stanford promote and sell its allegedly fraudulent certificates of deposit.
Errors and omissions claims, lawsuits, and other proceedings arising in the ordinary course of business are covered in part by
professional indemnity or other appropriate insurance. The terms of this insurance vary by policy year and self-insured risks
have increased significantly in recent years. Regarding self-insured risks, the Company has established provisions which are
believed to be adequate in the light of current information and legal advice, and the Company adjusts such provisions from time
to time according to developments. These provisions have been recognized in other operating expenses to the extent that losses are deemed probable and reasonably estimable. Matters that are not probable or reasonably estimable have not been provided for and the Company does not believe a reasonable possible range of losses, for these matters, can be estimated.
On the basis of current information, the Company does not expect that the actual claims, lawsuits and other proceedings to
which the Company is subject, or potential claims, lawsuits, and other proceedings relating to matters of which it is aware, will
ultimately have a material adverse effect on the Company’s financial condition, results of operations or liquidity. Nonetheless,
given the large or indeterminate amounts sought in certain of these actions, and the inherent unpredictability of litigation and
disputes with insurance companies, it is possible that an adverse outcome in certain matters could, from time to time, have a
material adverse effect on the Company’s results of operations or cash flows in particular quarterly or annual periods.

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Loss, Net of Tax	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
ACCUMULATED OTHER COMPREHENSIVE LOSS, NET OF TAX
	21	ACCUMULATED OTHER COMPREHENSIVE LOSS, NET OF TAX
	The components of other comprehensive (loss) income are as follows:
		31-Dec-14												31-Dec-13									31-Dec-12
		Before tax amount				Tax				Net of tax amount				Before tax amount			Tax			Net of tax amount			Before tax amount			Tax			Net of tax amount
		(millions)
	Other comprehensive (loss) income:
	Foreign currency translation adjustments	$	(183	)		$	—			$	(183	)		$	20		$	—		$	20		$	46		$	—		$	46
	Pension funding adjustments:
	Foreign currency translation on pension funding adjustments	49				(12		)		37				(15		)	5			(10		)	(31		)	9			(22		)
	Net actuarial (loss) gain	(274		)		19				(255		)		83			2			85			(203		)	36			(167		)
	Amortization of unrecognized actuarial loss	48				(8		)		40				55			(9		)	46			47			(9		)	38
	Amortization of unrecognized prior service gain and curtailment gain	(4		)		1				(3		)		(5		)	1			(4		)	(6		)	1			(5		)
	Curtailment gain	2				—				2				—			—			—			—			—			—
		(179		)		—				(179		)		118			(1		)	117			(193		)	37			(156		)
	Derivative instruments:
	Gain on interest rate swaps (effective element)	—				—				—				—			—			—			3			(1		)	2
	Interest rate reclassification adjustment	(5		)		1				(4		)		(5		)	1			(4		)	(5		)	1			(4		)
	(Loss) gain on forward exchange contracts (effective element)	(31		)		6				(25		)		10			(2		)	8			11			(2		)	9
	Forward exchange contract reclassification adjustment	16				(3		)		13				1			—			1			(4		)	1			(3		)
	Gain on treasury lock (effective element)	—				—				—				19			(4		)	15			—			—			—
	Treasury lock reclassification adjustment	(1		)		—				(1		)		—			—			—			—			—			—
		(21		)		4				(17		)		25			(5		)	20			5			(1		)	4
	Other comprehensive (loss) income	(383		)		4				(379		)		163			(6		)	157			(142		)	36			(106		)
	Less: Other comprehensive loss attributable to noncontrolling interests	6				—				6				—			—			—			—			—			—
	Other comprehensive (loss) income attributable to Willis Group Holdings	$	(377	)		$	4			$	(373	)		$	163		$	(6	)	$	157		$	(142	)	$	36		$	(106	)
	The components of accumulated other comprehensive loss, net of tax, are as follows:
		Net foreign currency translation adjustment				Pension funding adjustment				Net unrealized gain on derivative instruments				Total
		(millions)
	Balance, December 31, 2011	$	(80	)		$	(675	)		$	11			$	(744	)
	Other comprehensive income (loss) before reclassifications	46				(189		)		11				(132		)
	Amounts reclassified from accumulated other comprehensive income	—				33				(7		)		26
	Net current year other comprehensive income (loss), net of tax and noncontrolling interests	46				(156		)		4				(106		)
	Balance, December 31, 2012	$	(34	)		$	(831	)		$	15			$	(850	)
	Other comprehensive income before reclassifications	20				75				23				118
	Amounts reclassified from accumulated other comprehensive income	—				42				(3		)		39
	Net current year other comprehensive income, net of tax and noncontrolling interests	20				117				20				157
	Balance, December 31, 2013	$	(14	)		$	(714	)		$	35			$	(693	)
	Other comprehensive loss before reclassifications	(177		)		(216		)		(25		)		(418		)
	Amounts reclassified from accumulated other comprehensive income	—				37				8				45
	Net current year other comprehensive loss, net of tax and noncontrolling interests	(177		)		(179		)		(17		)		(373		)
	Balance, December 31, 2014	$	(191	)		$	(893	)		$	18			$	(1,066	)
	Amounts reclassified out of accumulated other comprehensive income into the statement of operations are as follows:
	Details about accumulated other comprehensive income components		Amount reclassified from accumulated other comprehensive income												Affected line item in the statement of operations
			Years ended December 31,
			2014				2013				2012
			(millions)
	Gains and losses on cash flow hedges (Note 24)
	Interest rate swaps		$	(5	)		$	(5	)		$	(5	)		Investment income
	Foreign exchange contracts		16				1				(4		)		Other income (expense), net
	Treasury lock		(1		)		—				—				Interest expense
			10				(4		)		(9		)		Total before tax
	Tax		(2		)		1				2
			$	8			$	(3	)		$	(7	)		Net of tax
	Amortization of defined benefit pension items (Note 17)
	Prior service gain and curtailment gain		$	(4	)		$	(5	)		$	(6	)		Salaries and benefits
	Net actuarial loss		48				55				47				Salaries and benefits
			44				50				41				Total before tax
	Tax		(7		)		(8		)		(8		)
			$	37			$	42			$	33			Net of tax
	Total reclassifications for the period		$	45			$	39			$	26

Equity_and_Noncontrolling_Inte

Equity and Noncontrolling Interests	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
EQUITY AND NONCONTROLLING INTERESTS
	22	EQUITY AND NONCONTROLLING INTEREST
	The effects on equity of changes in Willis Group Holdings, ownership interest in its subsidiaries are as follows:
		Years ended December 31,
		2014		2013			2012
				(millions)
	Net income (loss) attributable to Willis Group Holdings	$	362	$	365		$	(446	)
	Transfers from noncontrolling interest:
	Decrease in Willis Group Holdings’ paid-in capital for purchase of noncontrolling interest	—		(4		)	(31		)
	Increase in Willis Group Holdings’ paid-in capital for sale of noncontrolling interest	—		—			2
	Net transfers from noncontrolling interest	—		(4		)	(29		)
	Change from net income (loss) attributable to Willis Group Holdings and transfers from noncontrolling interests	$	362	$	361		$	(475	)

Supplemental_Disclosures_of_Ca

Supplemental Disclosures of Cash Flow Information	12 Months Ended
	Dec. 31, 2014
Supplemental Cash Flow Elements [Abstract]
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION
	23	SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION
	Supplemental disclosures regarding cash flow information and non-cash flow investing and financing activities are as follows:
		Years Ended December 31,
		2014		2013			2012
		(millions)
	Supplemental disclosures of cash flow information:
	Cash payments for income taxes, net	$	88	$	61		$	63
	Cash payments for interest	123		117			118
	Supplemental disclosures of non-cash investing and financing activities:
	Write-off of unamortized debt issuance costs	$	—	$	(2	)	$	—
	Write-back of fair value adjustment on 5.625% senior notes due 2015	—		7			—
	Assets acquired under capital leases	3		7			2
	Deferred payments on acquisitions of subsidiaries	10		2			4
	Acquisitions:
	Fair value of assets acquired	$	296	$	47		$	23
	Less:
	Liabilities assumed	107		30			3
	Cash acquired	57		1			—
	Net assets acquired, net of cash acquired	$	132	$	16		$	20

Derivative_Financial_Instrumen

Derivative Financial Instruments and Hedging Activities

12 Months Ended

Dec. 31, 2014

Derivative Instruments and Hedging Activities Disclosure [Abstract]

DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES

24

DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES

Fair value of derivative financial instruments

In addition to the note below, see Note 25 - Fair Value Measurements for information about the fair value hierarchy of derivatives.

Primary risks managed by derivative financial instruments

The main risks managed by derivative financial instruments are interest rate risk and foreign currency risk. The Company’s Board of Directors reviews and approves policies for managing each of these risks as summarized below.

The Company enters into derivative transactions (principally interest rate swaps and forward foreign currency contracts) in order to manage interest rate and foreign currency risks arising from the Company’s operations and its sources of finance. The Company does not hold financial or derivative instruments for trading purposes.

Interest Rate Risk — Investment Income

As a result of the Company’s operating activities, the Company holds Fiduciary funds. The Company earns interest on these funds, which is included in the Company’s financial statements as investment income. These funds are regulated in terms of access and the instruments in which they may be invested, most of which are short-term in maturity.

Through the fourth quarter of 2011, in order to manage interest rate risk relating to Fiduciary funds, the Company entered into interest rate swaps to receive a fixed rate of interest and pay a variable rate of interest denominated in the various currencies related to the short-term investments. During the second quarter 2012, the Company closed out its legacy position relating to such instruments. The fair value of these swaps at the close out date was $16 million, representing a cash settlement amount on termination. In connection with the terminated swaps, the Company retained a gain of $15 million in accumulated other comprehensive income. This gain is being reclassified into earnings in line with the forecasted swap transactions. The Company expects approximately $1 million of the gain to be recognized in the consolidated statement of operations in 2015.

At December 31, 2014 and 2013, the Company had no derivative financial instruments that were designated as cash flow hedges of interest rate risk in investments.

Interest Rate Risk — Interest Expense

The Company's operations are financed principally by $2,054 million fixed rate senior notes maturing through 2043 and $259 million under a 7-year term loan facility. The Company has access to (i) $800 million under a revolving credit facility expiring July 23, 2018, (ii) $400 million under a revolving credit facility expiring April 28, 2015, which will be available for regulatory capital purposes related to securities underwriting only, and (iii) $22 million under two further revolving credit facilities, of which $20 million is also only available for specific regulatory purposes. As of December 31, 2014 $nil (2013: $nil) was drawn on these facilities.

The 7-year term loan facility bears interest at LIBOR plus 1.50% and drawings under the revolving credit facility bear interest at LIBOR plus 1.50%. These margins apply while the Company’s debt rating remains BBB-/Baa3. Should the Company’s debt rating change, then the margin will change in accordance with the credit facilities agreements. The fixed rate senior notes bear interest at various rates as detailed in Note 18 — ‘Debt’.

During the year ended December 31, 2010, the Company entered into a series of interest rate swaps for a total notional amount of $350 million to receive a fixed rate and pay a variable rate on a semi-annual basis, with a maturity date of July 15, 2015. The Company had previously designated these instruments as fair value hedges against its $350 million 5.625% senior notes due 2015 and had accounted for them accordingly until the first quarter of 2013 at which point these swaps, although remaining as economic hedges, no longer qualified for hedge accounting.

During the year ended December 31, 2013, the Company closed out the above interest rate swaps and received a cash settlement of $13 million on termination.

To hedge against the potential variability in benchmark interest rates in advance of the anticipated debt issuance, the Company entered into two short-term treasury locks during the three months ended June 30, 2013. These were closed out during the three months ended September 30, 2013 following the issue of the new senior notes described in Note 18 - 'Debt'. The fair value of these treasury locks at the close out date was $21 million, received as a cash settlement on termination.

The Company had designated the Treasury locks as effective hedges of the anticipated transaction and had recognized a gain of $19 million in other comprehensive income in relation to the effective element that qualified for hedge accounting at that date. This amount will be reclassified into earnings consistent with the recognition of interest expense on the 4.625% senior notes due 2023 and the 6.125% senior notes due 2043. In addition, the Company recognized a $2 million gain in interest expense in the year ended December 31, 2013 for the portion of the treasury locks determined as ineffective.

Foreign Currency Risk

The Company’s primary foreign exchange risks arise:

•

from changes in the exchange rate between US dollars and pounds sterling as its London market operations earn the majority of their revenues in US dollars and incur expenses predominantly in Pounds sterling, and may also hold a significant net sterling asset or liability position on the balance sheet. In addition, the London market operations earn significant revenues in Euros and Japanese yen; and

•

from the translation into US dollars of the net income and net assets of its foreign subsidiaries, excluding the London market operations which are US dollar denominated.

The foreign exchange risks in its London market operations are hedged as follows:

•

to the extent that forecast Pound sterling expenses exceed Pound sterling revenues, the Company limits its exposure to this exchange rate risk by the use of forward contracts matched to specific, clearly identified cash outflows arising in the ordinary course of business; and

•

to the extent the UK operations earn significant revenues in Euros and Japanese yen, the Company limits its exposure to changes in the exchange rate between the US dollar and these currencies by the use of forward contracts matched to a percentage of forecast cash inflows in specific currencies and periods. In addition, we are also exposed to foreign exchange risk on any net sterling asset or liability position in our London market operations.

The fair value of foreign currency contracts is recorded in other assets and other liabilities. For contracts that qualify as accounting hedges, changes in fair value resulting from movements in the spot exchange rate are recorded as a component of other comprehensive income whilst changes resulting from a movement in the time value are recorded in interest expense. For contracts that do not qualify for hedge accounting, the total change in fair value is recorded in interest expense. Amounts held in comprehensive income are reclassified into earnings when the hedged exposure affects earnings.

At December 31, 2014 and 2013, the Company’s foreign currency contracts were all designated as hedging instruments except for those relating to short-term cash flows and hedges of certain intercompany loans.

The table below summarizes by major currency the contractual amounts of the Company’s forward contracts to exchange foreign currencies for Pounds sterling in the case of US dollars and US dollars for euro and Japanese yen. Foreign currency notional amounts are reported in US dollars translated at contracted exchange rates.

December 31,

Sell

Sell

2014(i)

2013

(millions)

US dollar

$

678

$

303

Euro

186

97

Japanese yen

51

35

_________________________________

(i)

Forward exchange contracts range in maturity from 2015 to 2017.

In addition to forward exchange contracts, we undertake short-term foreign exchange swaps for liquidity purposes. These are not designated as hedges and do not qualify for hedge accounting. The fair values at December 31, 2014 and 2013 were immaterial.

During the year ended December 31, 2014, the Company entered into a number of foreign currency transactions in order to hedge certain intercompany loans. These derivatives were not designated as hedging instruments and were for a total notional amount of $352 million (December 31, 2013: $228 million). In respect of these transactions, an immaterial amount has been recognized as an asset within other current assets and an equivalent gain has been recognized in other income (expense), net, for the period.

In addition during the year ended December 31, 2014, in order to hedge the Company's exposure relating to the purchase price consideration for acquiring a 75.8 percent holding in Max Matthiessen AB, the Company entered into a series of forward exchange contracts. As a result of these transactions the Company recognized a $14 million expense in other income (expense), net, and an equivalent reduction to cash and cash equivalents in the year.

Derivative financial instruments

The table below presents the fair value of the Company’s derivative financial instruments and their balance sheet classification at December 31:

Fair value

Balance sheet

December 31,

December 31,

Derivative financial instruments designated as hedging instruments:

classification

2014

2013

(millions)

Assets:

Forward exchange contracts

Other assets

26

23

Total derivatives designated as hedging instruments

$

26

$

23

Liabilities:

Forward exchange contracts

Other liabilities

21

2

Total derivatives designated as hedging instruments

$

21

$

2

Cash Flow Hedges

The table below presents the effects of derivative financial instruments in cash flow hedging relationships on the consolidated statements of operations and the consolidated statements of equity for years ended December 31, 2014, 2013 and 2012:

Derivatives in cash flow hedging relationships

Amount of

Location of gain (loss)

Amount of

Location of gain (loss)

Amount of

gain (loss)

reclassified from accumulated OCI(i) into income (effective element)

gain (loss)

recognized in income

gain (loss)

recognized

reclassified

on derivative (ineffective hedges and ineffective element of effective hedges)

recognized

in OCI(i)on derivative (effective element)

from

in income

accumulated

on derivative

OCI(i) into

(ineffective

income(effective element)

hedges and

ineffective

element of effective hedges)

(millions)

(millions)

(millions)

Year Ended December 31, 2014

Interest rate swaps

$

—

Investment income

$

(5

)

Other income (expense), net

$

—

Treasury locks

—

Interest expense

(1

)

Interest expense

—

Forward exchange contracts

(31

)

Other income (expense), net

16

Interest expense

(1

)

Total

$

(31

)

$

10

$

(1

)

Year Ended December 31, 2013

Interest rate swaps

$

—

Investment income

$

(5

)

Other income (expense), net

$

—

Treasury locks

19

Interest expense

—

Interest expense

2

Forward exchange contracts

10

Other income (expense), net

1

Interest expense

1

Total

$

29

$

(4

)

$

3

Year Ended December 31, 2012

Interest rate swaps

$

3

Investment income

$

(5

)

Other income (expense), net

$

—

Forward exchange contracts

11

Other income (expense), net

(4

)

Interest expense

1

Total

$

14

$

(9

)

$

1

_________________________________

Amounts above shown gross of tax.

(i)

OCI means other comprehensive income.

For interest rate swaps all components of each derivative’s gain or loss were included in the assessment of hedge effectiveness. For foreign exchange contracts, only the changes in fair value resulting from movements in the spot exchange rate are included in this assessment. In instances where the timing of expected cash flows can be matched exactly to the maturity of the foreign exchange contract, then changes in fair value attributable to movement in the forward points are also included.

At December 31, 2014 the Company estimates there will be $7 million of net derivative gains reclassified from accumulated comprehensive income into earnings within the next twelve months as the forecasted transactions affect earnings.

Credit Risk and Concentrations of Credit Risk

Credit risk represents the loss that would be recognized at the reporting date if counterparties failed to perform as contracted and from movements in interest rates and foreign exchange rates. The Company currently does not anticipate non-performance by its counterparties. The Company generally does not require collateral or other security to support financial instruments with credit risk.

Concentrations of credit risk that arise from financial instruments exist for groups of customers or counterparties when they have similar economic characteristics that would cause their ability to meet contractual obligations to be similarly affected by changes in economic or other conditions. Financial instruments on the balance sheet that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents, fiduciary funds, accounts receivable and derivatives which are recorded at fair value.

The Company maintains a policy providing for the diversification of cash and cash equivalent investments and places such investments in an extensive number of financial institutions to limit the amount of credit risk exposure. These financial institutions are monitored on an ongoing basis for credit quality predominantly using information provided by credit agencies.

Concentrations of credit risk with respect to receivables are limited due to the large number of clients and markets in which the Company does business, as well as the dispersion across many geographic areas. Management does not believe significant risk exists in connection with the Company's concentrations of credit as of December 31, 2014.

Fair_Value_Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS
	25	FAIR VALUE MEASUREMENTS
	The Company has categorized its assets and liabilities that are measured at fair value on a recurring and non-recurring basis into a three-level fair value hierarchy, based on the reliability of the inputs used to determine fair value as follows:
	•	Level 1: refers to fair values determined based on quoted market prices in active markets for identical assets;
	•	Level 2: refers to fair values estimated using observable market based inputs or unobservable inputs that are corroborated by market data; and
	•	Level 3: includes fair values estimated using unobservable inputs that are not corroborated by market data.
	The following methods and assumptions were used by the Company in estimating its fair value disclosure for financial instruments:
	Long-term debt (excluding related fair value hedges)-Fair values are based on quoted market values and so classified as Level 1 measurements.
	Derivative financial instruments-Market values have been used to determine the fair value of interest rate swaps and forward foreign exchange contracts based on estimated amounts the Company would receive or have to pay to terminate the agreements, taking into account the current interest rate environment or current foreign currency forward rates. Such financial instruments are classified as Level 2 in the fair value hierarchy.
	Financial instruments measured at fair value on a recurring basis
	The following table presents, for each of the fair-value hierarchy levels, the Company's assets and liabilities that are measured at fair value on a recurring basis.
		31-Dec-14
		Quoted		Significant		Significant
		prices in		other		other
		active		observable		unobservable
		markets		inputs		inputs
		for
		identical
		assets
		Level 1		Level 2		Level 3		Total
				(millions)
	Assets at fair value:
	Derivative financial instruments	—		26		—		26
	Total assets	$	—	$	26	$	—	$	26
	Liabilities at fair value:
	Derivative financial instruments	$	—	$	21	$	—	$	21
	Total liabilities	$	—	$	21	$	—	$	21
		31-Dec-13
		Quoted		Significant		Significant
		prices in		other		other
		active		observable		unobservable
		markets		inputs		inputs
		for
		identical
		assets
		Level 1		Level 2		Level 3		Total
				(millions)
	Assets at fair value:
	Derivative financial instruments	—		23		—		23
	Total assets	$	—	$	23	$	—	$	23
	Liabilities at fair value:
	Derivative financial instruments	$	—	$	2	$	—	$	2
	Total liabilities	$	—	$	2	$	—	$	2
	Fair value information about financial instruments not measured at fair value
	The following table presents the carrying values and estimated fair values of the Company's financial instruments not measured at fair value. The fair value amounts shown below are not necessarily indicative of the amounts that the Company would realize upon disposition nor do they indicate the Company’s intent or ability to dispose of the financial instrument.
		December 31,
		2014				2013
		Carrying		Fair		Carrying		Fair
		amount		value		amount		value
				(millions)
	Assets:
	Cash and cash equivalents	$	635	$	635	$	796	$	796
	Fiduciary funds (included within Fiduciary assets)	$	1,888	$	1,888	$	1,662	$	1,662
	Liabilities:
	Current portion of long-term debt	$	167	$	169	$	15	$	15
	Long-term debt	2,142		2,327		2,311		2,444
	Financial instruments measured at fair value on a non-recurring basis
	The remeasurement of goodwill is classified as non-recurring level 3 fair value assessment due to the significance of unobservable inputs developed using company-specific information, see Note 12 - Goodwill.

Segment_Information

Segment Information	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
SEGMENT INFORMATION
	26	SEGMENT INFORMATION
	During the periods presented, the Company operated through three reporting segments: Global, North America and International. Global provides specialist brokerage and consulting services to clients worldwide for specific industrial and commercial activities and is organized by specialism. North America and International predominantly comprise our retail operations which provide services to small, medium and large corporations, accessing Global’s specialist expertise when required.
	The Company uses segment operating income (loss) to measure segment performance. The Company does not allocate all expenses that form part of total expenses in the consolidated statements of operations to its operating segments because management does not include this information in its measurement of the performance of those segments. Because of this unallocated expense, the operating income (loss) of each reporting segment does not reflect the operating income (loss) reporting segment would report as a stand-alone business.
	The accounting policies of the segments are consistent with those described in Note 2 — 'Basis of Presentation and Significant Accounting Policies'.
	There are no inter-segment revenues, with segments operating on a revenue-sharing basis equivalent to that used when sharing business with other third-party brokers.
	Selected information regarding the Company’s segments is as follows:
		Commissions			Investment			Other			Total		Depreciation		Operating
		and fees			income			income			revenues		and		income (loss)
													amortization
											(millions)
	Year Ended December 31, 2014
	Global	$	1,386		$	9		$	15		$	1,410	$	36	$	352
	North America	1,365			1			4			1,370		71		273
	International	1,016			6			—			1,022		27		197
	Total segments	3,767			16			19			3,802		134		822
	Corporate and other(i)	—			—			—			—		12		(175		)
	Total consolidated	$	3,767		$	16		$	19		$	3,802	$	146	$	647
	Year Ended December 31, 2013
	Global	$	1,358		$	6		$	—		$	1,364	$	36	$	376
	North America	1,349			2			7			1,358		77		249
	International	926			7			—			933		22		178
	Total segments	3,633			15			7			3,655		135		803
	Corporate and other(i)	—			—			—			—		14		(140		)
	Total consolidated	$	3,633		$	15		$	7		$	3,655	$	149	$	663
	Year Ended December 31, 2012
	Global	$	1,303		$	7		$	—		$	1,310	$	33	$	400
	North America	1,281			3			4			1,288		76		252
	International	874			8			—			882		23		167
	Total segments	3,458			18			4			3,480		132		819
	Corporate and other(i)	—			—			—			—		6		(1,044		)
	Total consolidated	$	3,458		$	18		$	4		$	3,480	$	138	$	(225	)
	_________________________________
	(i)	See the following table for an analysis of the ‘Corporate and other’ line.
		Years ended December 31,
		2014			2013			2012
		(millions)
	Costs of the holding company	$	(13	)	$	(10	)	$	(4	)
	Costs related to Group functions, leadership and projects	(194		)	(118		)	(114		)
	Non-servicing elements of defined benefit pension	53			42			38
	Significant legal and regulatory settlements managed centrally	(2		)	(6		)	(6		)
	Restructuring costs relating to the Operational Improvement Program	(17		)	—			—
	Additional incentive accrual for change in remuneration policy	—			—			(252		)
	Write-off of unamortized cash retention awards debtor	—			—			(200		)
	Goodwill impairment charge	—			—			(492		)
	India joint venture settlement	—			—			(11		)
	Insurance recovery	—			—			10
	Write-off of uncollectible accounts receivable balance in Chicago	—			—			(13		)
	Expense Reduction Initiative	—			(46		)	—
	Fees related to the extinguishment of debt	—			(1		)	—
	Other	(2		)	(1		)	—
	Total Corporate and Other	$	(175	)	$	(140	)	$	(1,044	)
	The following table reconciles total consolidated operating income (loss), as disclosed in the operating segment tables above, to consolidated income from continuing operations before income taxes and interest in earnings of associates.
		Years ended December 31,
		2014			2013			2012
		(millions)
	Total consolidated operating income (loss)	$	647		$	663		$	(225	)
	Other (expense) income, net	6			22			16
	Loss on extinguishment of debt	—			(60		)	—
	Interest expense	(135		)	(126		)	(128		)
	Income (loss) before income taxes and interest in earnings of associates	$	518		$	499		$	(337	)
	The Company does not currently provide asset information by reportable segment as it does not routinely evaluate the total asset position by segment.
	Segment revenue by product is as follows:
		Years ended December 31,
	2014			2013			2012			2014		2013		2012			2014		2013		2012		2014		2013		2012
	Global									North America							International						Total
	(millions)
Commissions and fees:
Retail insurance services	$	153		$	158		$	165		$	1,365	$	1,349	$	1,281		$	1,016	$	926	$	874	$	2,534	$	2,433	$	2,320
Specialty insurance services	1,233			1,200			1,138			—		—		—			—		—		—		1,233		1,200		1,138
Total commissions and fees	1,386			1,358			1,303			1,365		1,349		1,281			1,016		926		874		3,767		3,633		3,458
Investment income	9			6			7			1		2		3			6		7		8		16		15		18
Other income	15			—			—			4		7		4			—		—		—		19		7		4
Total Revenues	$	1,410		$	1,364		$	1,310		$	1,370	$	1,358	$	1,288		$	1,022	$	933	$	882	$	3,802	$	3,655	$	3,480
None of the Company’s customers represented more than 10 percent of the Company’s consolidated commissions and fees for the years ended December 31, 2014, 2013 and 2012.
Information regarding the Company’s geographic locations is as follows:
	Years Ended December 31,
	2014			2013			2012
	(millions)
Commissions and fees(i)
UK	$	1,027		$	1,026		$	980
US	1,592			1,549			1,484
Other(ii)	1,148			1,058			994
Total	$	3,767		$	3,633		$	3,458
	December 31,
	2014			2013
	(millions)
Fixed assets
UK	$	232		$	233
US	193			203
Other(ii)	58			45
Total	$	483		$	481
_________________________________
(i)	Commissions and fees are attributed to countries based upon the location of the subsidiary generating the revenue.
(ii)	Other than in the United Kingdom and the United States, the Company does not conduct business in any country in which its commissions and fees and or fixed assets exceed 10 percent of consolidated commissions and fees and or fixed assets, respectively.

Subsidiary_Undertakings

Subsidiary Undertakings	12 Months Ended
	Dec. 31, 2014
Investments in and Advances to Affiliates, Schedule of Investments [Abstract]
SUBSIDIARY UNDERTAKINGS
	27	SUBSIDIARY UNDERTAKINGS
	The Company has investments in the following subsidiary undertakings which principally affect the net income or net assets of the Group.
	Subsidiary name		Country of registration	Class of share	Percentage ownership
	Holding companies
	TAI Limited		England and Wales	Ordinary shares	100	%
	Trinity Acquisition Limited		England and Wales	Ordinary shares	100	%
	Willis Faber Limited		England and Wales	Ordinary shares	100	%
	Willis Group Limited		England and Wales	Ordinary shares	100	%
	Willis Investment UK Holdings Limited		England and Wales	Ordinary shares	100	%
	Willis Netherlands Holdings B.V.		Netherlands	Ordinary shares	100	%
	Willis Europe B.V.		England and Wales	Ordinary shares	100	%
	Insurance broking companies
	Willis HRH, Inc.		USA	Common shares	100	%
	Willis Limited		England and Wales	Ordinary shares	100	%
	Willis North America, Inc.		USA	Common shares	100	%
	Willis Re, Inc.		USA	Common shares	100	%

Financial_Information_for_Pare

Financial Information for Parent Guarantor, Other Guarantor Subsidiaries and Non-Guarantor Subsidiaries	12 Months Ended
	Dec. 31, 2014
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
FINANCIAL INFORMATION FOR PARENT GUARANTOR, OTHER GUARANTOR SUBSIDIARIES AND NON-GUARANTOR SUBSIDIARIES
	28	FINANCIAL INFORMATION FOR PARENT GUARANTOR, OTHER GUARANTOR SUBSIDIARIES AND NON-GUARANTOR SUBSIDIARIES
	Willis North America Inc. (‘Willis North America’) has $148 million senior notes outstanding that were issued on July 1, 2005, $394 million of senior notes issued on March 28, 2007 and $187 million of senior notes issued on September 29, 2009.
	All direct obligations under the senior notes are jointly and severally, irrevocably and fully and unconditionally guaranteed by Willis Netherlands Holdings B.V., Willis Investment UK Holdings Limited, TA I Limited, Trinity Acquisition Limited (previously registered as Trinity Acquisition plc) and Willis Group Limited, collectively the 'Other Guarantors', and with Willis Group Holdings, the 'Guarantor Companies'.
	The debt securities that were issued by Willis North America and guaranteed by the entities described above, and for which the disclosures set forth below relate and are required under applicable SEC rules, were issued under an effective registration statement.
	Presented below is condensed consolidating financial information for:
	(i)	Willis Group Holdings, which is a guarantor, on a parent company only basis;
	(ii)	the Other Guarantors, which are all 100 percent directly or indirectly owned subsidiaries of the parent and are all direct or indirect parents of the issuer;
	(iii)	the Issuer, Willis North America;
	(iv)	Other, which are the non-guarantor subsidiaries, on a combined basis;
	(v)	Consolidating adjustments; and
	(vi)	the Consolidated Company.
	The equity method has been used for investments in subsidiaries in the condensed consolidating balance sheets for the year ended December 31, 2014 of Willis Group Holdings, the Other Guarantors and the Issuer.
	Condensed Consolidating Statement of Operations
		Year Ended December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	REVENUES
	Commissions and fees	$	—		$	—		$	8		$	3,759		$	—		$	3,767
	Investment income	—			—			—			16			—			16
	Other income	—			—			—			19			—			19
	Total revenues	—			—			8			3,794			—			3,802
	EXPENSES
	Salaries and benefits	(1		)	—			(81		)	(2,232		)	—			(2,314		)
	Other operating expenses	(16		)	(95		)	(38		)	(510		)	—			(659		)
	Depreciation expense	—			(4		)	(17		)	(71		)	—			(92		)
	Amortization of intangible assets	—			—			—			(54		)	—			(54		)
	Restructuring costs	—			(11		)	(3		)	(22		)	—			(36		)
	Total expenses	(17		)	(110		)	(139		)	(2,889		)	—			(3,155		)
	OPERATING (LOSS) INCOME	(17		)	(110		)	(131		)	905			—			647
	Other (expense) income, net	(15		)	(220		)	—			11			230			6
	Income from Group undertakings	—			221			313			102			(636		)	—
	Expenses due to Group undertakings	—			(33		)	(179		)	(424		)	636			—
	Interest expense	(43		)	(35		)	(45		)	(12		)	—			(135		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(177		)	(42		)	582			230			518
	Income taxes	—			25			24			(208		)	—			(159		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(152		)	(18		)	374			230			359
	Interest in earnings of associates, net of tax	—			10			—			4			—			14
	Equity account for subsidiaries	437			570			76			—			(1,083		)	—
	NET INCOME	362			428			58			378			(853		)	373
	Less: Net loss attributable to noncontrolling interests	—			—			—			(11		)	—			(11		)
	NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	362		$	428		$	58		$	367		$	(853	)	$	362
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	Comprehensive (loss) income	$	(11	)	$	69		$	(110	)	$	49		$	(3	)	$	(6	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(5		)	—			(5		)
	Comprehensive (loss) income attributable to Willis Group Holdings	$	(11	)	$	69		$	(110	)	$	44		$	(3	)	$	(11	)
	Condensed Consolidating Statement of Operations
		Year Ended December 31, 2013
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	REVENUES
	Commissions and fees	$	—		$	—		$	8		$	3,625		$	—		$	3,633
	Investment income	—			—			—			15			—			15
	Other income	—			—			—			7			—			7
	Total revenues	—			—			8			3,647			—			3,655
EXPENSES
Salaries and benefits	(1		)	—			(103		)	(2,103		)	—			(2,207		)
Other operating expenses	(5		)	(69		)	(163		)	(399		)	—			(636		)
Depreciation expense	—			(3		)	(20		)	(71		)	—			(94		)
Amortization of intangible assets	—			—			—			(55		)	—			(55		)
Total expenses	(6		)	(72		)	(286		)	(2,628		)	—			(2,992		)
OPERATING (LOSS) INCOME	(6		)	(72		)	(278		)	1,019			—			663
Other income (expense), net	5			(4		)	—			31			(10		)	22
Income from Group undertakings	—			191			364			86			(641		)	—
Expenses due to Group undertakings	(10		)	(34		)	(141		)	(456		)	641			—
Loss on extinguishment of debt	—			—			(60		)	—			—			(60		)
Interest expense	(42		)	(16		)	(63		)	(5		)	—			(126		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(53		)	65			(178		)	675			(10		)	499
Income taxes	—			23			—			(145		)	—			(122		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(53		)	88			(178		)	530			(10		)	377
Interest in earnings of associates, net of tax	—			9			—			(9		)	—			—
Equity account for subsidiaries	418			320			150			—			(888		)	—
NET INCOME (LOSS)	365			417			(28		)	521			(898		)	377
Less: Net income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
NET INCOME (LOSS) ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	365		$	417		$	(28	)	$	509		$	(898	)	$	365
Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
Comprehensive income	$	522		$	565		$	74		$	636		$	(1,263	)	$	534
Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
Comprehensive income attributable to Willis Group Holdings	$	522		$	565		$	74		$	624		$	(1,263	)	$	522
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	—		$	—		$	3,458		$	—		$	3,458
Investment income	—			—			1			17			—			18
Other income	—			—			—			4			—			4
Total revenues	—			—			1			3,479			—			3,480
EXPENSES
Salaries and benefits	(2		)	—			(96		)	(2,377		)	—			(2,475		)
Other operating expenses	(6		)	(80		)	(78		)	(436		)	—			(600		)
Depreciation expense	—			(1		)	(15		)	(63		)	—			(79		)
Amortization of intangible assets	—			—			—			(59		)	—			(59		)
Goodwill impairment charge	—			—			—			(492		)	—			(492		)
Total expenses	(8		)	(81		)	(189		)	(3,427		)	—			(3,705		)
OPERATING (LOSS) INCOME	(8		)	(81		)	(188		)	52			—			(225		)
Other income (expense), net	2			(2		)	(1		)	17			—			16
Income from Group undertakings	—			201			316			111			(628		)	—
Expenses due to Group undertakings	—			(67		)	(147		)	(414		)	628			—
Interest expense	(43		)	(7		)	(70		)	(8		)	—			(128		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(49		)	44			(90		)	(242		)	—			(337		)
Income taxes	—			31			34			(166		)	—			(101		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(49		)	75			(56		)	(408		)	—			(438		)
Interest in earnings of associates, net of tax	—			8			—			(3		)	—			5
Equity account for subsidiaries	(397		)	(480		)	(172		)	—			1,049			—
NET LOSS	(446		)	(397		)	(228		)	(411		)	1,049			(433		)
Less: Net income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
NET LOSS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	(446	)	$	(397	)	$	(228	)	$	(424	)	$	1,049		$	(446	)
Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
Comprehensive loss	$	(552	)	$	(494	)	$	(263	)	$	(519	)	$	1,289		$	(539	)
Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
Comprehensive loss attributable to Willis Group Holdings	$	(552	)	$	(494	)	$	(263	)	$	(532	)	$	1,289		$	(552	)
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	9		$	2		$	—		$	624		$	—		$	635
Accounts receivable, net	—			—			4			1,040			—			1,044
Fiduciary assets	—			—			—			8,948			—			8,948
Deferred tax assets	—			—			—			12			—			12
Other current assets	1			27			10			205			(29		)	214
Amounts due from Group undertakings	3,674			924			1,057			1,114			(6,769		)	—
Total current assets	3,684			953			1,071			11,943			(6,798		)	10,853
NON-CURRENT ASSETS
Investments in subsidiaries	—			2,536			721			—			(3,257		)	—
Fixed assets, net	—			20			42			421			—			483
Goodwill	—			—			—			2,937			—			2,937
Other intangible assets, net	—			—			—			450			—			450
Investments in associates	—			147			—			22			—			169
Deferred tax assets	—			—			—			9			—			9
Pension benefits asset	—			—			—			314			—			314
Other non-current assets	3			8			2			207			—			220
Non-current amounts due from Group undertakings	—			518			740			—			(1,258		)	—
Total non-current assets	3			3,229			1,505			4,360			(4,515		)	4,582
TOTAL ASSETS	$	3,687		$	4,182		$	2,576		$	16,303		$	(11,313	)	$	15,435
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,948		$	—		$	8,948
Deferred revenue and accrued expenses	1			4			30			584			—			619
Income taxes payable	—			—			7			55			(29		)	33
Short-term debt and current portion of long-term debt	—			17			149			1			—			167
Deferred tax liabilities	—			—			—			21			—			21
Other current liabilities	67			11			46			320			—			444
Amounts due to Group undertakings	—			4,374			1,499			896			(6,769		)	—
Total current liabilities	68			4,406			1,731			10,825			(6,798		)	10,232
NON-CURRENT LIABILITIES
Investments in subsidiaries	838			—			—			—			(838		)	—
Long-term debt	796			765			581			—			—			2,142
Liabilities for pension benefits	—			—			—			284			—			284
Deferred tax liabilities	—			—			—			128			—			128
Provisions for liabilities	—			—			—			194			—			194
Other non-current liabilities	—			—			17			372			—			389
Non-current amounts due to Group undertakings	—			—			518			740			(1,258		)	—
Total non-current liabilities	1,634			765			1,116			1,718			(2,096		)	3,137
TOTAL LIABILITIES	$	1,702		$	5,171		$	2,847		$	12,543		$	(8,894	)	$	13,369
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REDEEMABLE NONCONTROLLING INTEREST	—			—			—			59			—			59
EQUITY
Total Willis Group Holdings stockholders’ equity	1,985			(989		)	(271		)	3,679			(2,419		)	1,985
Noncontrolling interests	—			—			—			22			—			22
Total equity	1,985			(989		)	(271		)	3,701			(2,419		)	2,007
TOTAL LIABILITIES AND EQUITY	$	3,687		$	4,182		$	2,576		$	16,303		$	(11,313	)	$	15,435
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	3		$	3		$	—		$	790		$	—		$	796
Accounts receivable, net	—			—			4			1,037			—			1,041
Fiduciary assets	—			—			—			8,412			—			8,412
Deferred tax assets	—			—			—			16			(1		)	15
Other current assets	1			21			10			186			(21		)	197
Amounts due by group undertakings	4,051			903			1,317			1,484			(7,755		)	—
Total current assets	4,055			927			1,331			11,925			(7,777		)	10,461
NON-CURRENT ASSETS
Investments in subsidiaries	—			2,838			1,021			—			(3,859		)	—
Fixed assets, net	—			15			51			415			—			481
Goodwill	—			—			—			2,838			—			2,838
Other intangible assets, net	—			—			—			353			—			353
Investments in associates	—			156			—			20			—			176
Deferred tax assets	—			—			—			7			—			7
Pension benefits asset	—			—			—			278			—			278
Other non-current assets	4			9			5			188			—			206
Non-current amounts due by group undertakings	—			518			690			—			(1,208		)	—
Total non-current assets	4			3,536			1,767			4,099			(5,067		)	4,339
TOTAL ASSETS	$	4,059		$	4,463		$	3,098		$	16,024		$	(12,844	)	$	14,800
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,412		$	—		$	8,412
Deferred revenue and accrued expenses	2			1			28			555			—			586
Income taxes payable	—			3			—			39			(21		)	21
Short-term debt and current portion of long-term debt	—			15			—			—			—			15
Deferred tax liabilities	—			—			—			25			—			25
Other current liabilities	62			15			38			300			—			415
Amounts due to group undertakings	—			4,760			1,662			1,333			(7,755		)	—
Total current liabilities	64			4,794			1,728			10,664			(7,776		)	9,474
NON-CURRENT LIABILITIES
Investments in subsidiaries	985			—			—			—			(985		)	—
Long-term debt	795			782			733			1			—			2,311
Liabilities for pension benefits	—			—			—			136			—			136
Deferred tax liabilities	—			1			—			55			—			56
Provisions for liabilities	—			—			—			206			—			206
Other non-current liabilities	—			—			48			326			—			374
Non-current amounts due to group undertakings	—			—			518			690			(1,208		)	—
Total non-current liabilities	1,780			783			1,299			1,414			(2,193		)	3,083
TOTAL LIABILITIES	$	1,844		$	5,577		$	3,027		$	12,078		$	(9,969	)	$	12,557
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
EQUITY
Total Willis Group Holdings stockholders’ equity	2,215			(1,114		)	71			3,918			(2,875		)	2,215
Noncontrolling interests	—			—			—			28			—			28
Total equity	2,215			(1,114		)	71			3,946			(2,875		)	2,243
TOTAL LIABILITIES AND EQUITY	$	4,059		$	4,463		$	3,098		$	16,024		$	(12,844	)	$	14,800
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(35	)	$	387		$	265		$	212		$	(352	)	$	477
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			1			6			(1		)	6
Additions to fixed assets	—			(9		)	(10		)	(95		)	1			(113		)
Additions to intangibles assets	—			—			—			(4		)	—			(4		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(241		)	—			(241		)
Payments to acquire other investments	—			—			—			(10		)	—			(10		)
Proceeds from sale of operations, net of cash disposed	—			—			—			86			—			86
Proceeds from intercompany investing activities	361			—			120			435			(916		)	—
Repayments of intercompany investing activities	—			(53		)	(131		)	(46		)	230			—
Additional investment in subsidiaries	(31		)	—			—			—			31			—
Net cash provided by (used in) investing activities	330			(62		)	(20		)	131			(655		)	(276		)
CASH FLOWS FROM FINANCING ACTIVITIES
Debt issuance costs	—			—			—			(3		)	—			(3		)
Repayments of debt	—			(15		)	—			—			—			(15		)
Repurchase of shares	(213		)	—			—			—			—			(213		)
Proceeds from issue of shares	134			—			—			31			(31		)	134
Excess tax benefits from share-based payment arrangements	—			—			—			5			—			5
Dividends paid	(210		)	—			—			(352		)	352			(210		)
Acquisition of noncontrolling interests	—			(4		)	—			—			—			(4		)
Dividends paid to noncontrolling interests	—			—			—			(17		)	—			(17		)
Proceeds from intercompany financing activities	—			46			4			180			(230		)	—
Repayments of intercompany financing activities	—			(353		)	(249		)	(314		)	916			—
Net cash used in financing activities	(289		)	(326		)	(245		)	(470		)	1,007			(323		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	6			(1		)	—			(127		)	—			(122		)
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(39		)	—			(39		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3			3			—			790			—			796
CASH AND CASH EQUIVALENTS, END OF YEAR	$	9		$	2		$	—		$	624		$	—		$	635
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH PROVIDED BY OPERATING ACTIVITIES	$	4		$	125		$	7		$	662		$	(237	)	$	561
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			3			9			—			12
Additions to fixed assets	—			(7		)	(11		)	(94		)	—			(112		)
Additions to intangible assets	—			—			—			(7		)	—			(7		)
Acquisitions of subsidiaries, net of cash acquired	—			(237		)	(230		)	(30		)	467			(30		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from sale of associates	—			—			—			4			—			4
Proceeds from sale of operations, net of cash disposed	—			—			230			257			(467		)	20
Proceeds from intercompany investing activities	383			211			36			60			(690		)	—
Repayments of intercompany investing activities	(347		)	(442		)	(120		)	(780		)	1,689			—
Net cash provided by (used in) investing activities	36			(475		)	(92		)	(588		)	999			(120		)
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued	—			522			—			—			—			522
Debt issuance costs	—			(8		)	—			—			—			(8		)
Repayments of debt	—			(15		)	(521		)	—			—			(536		)
Tender premium on extinguishment of senior notes	—			—			(65		)	—			—			(65		)
Proceeds from issue of shares	155			—			—			—			—			155
Excess tax benefits from share-based payment arrangements	—			—			—			2			—			2
Dividends paid	(193		)	—			(230		)	(7		)	237			(193		)
Acquisition of noncontrolling interests	—			—			—			(4		)	—			(4		)
Dividends paid to noncontrolling interests	—			—			—			(10		)	—			(10		)
Proceeds from intercompany financing activities	—			321			901			467			(1,689		)	—
Repayments of intercompany financing activities	—			(467		)	—			(223		)	690			—
Net cash (used in) provided by financing activities	(38		)	353			85			225			(762		)	(137		)
INCREASE IN CASH AND CASH EQUIVALENTS	2			3			—			299			—			304
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(8		)	—			(8		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	1			—			—			499			—			500
CASH AND CASH EQUIVALENTS, END OF YEAR	$	3		$	3		$	—		$	790		$	—		$	796
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(23	)	$	1,504		$	(44	)	$	(97	)	$	(815	)	$	525
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			—			5			—			5
Additions to fixed assets	—			(7		)	(19		)	(109		)	—			(135		)
Additions to intangible assets	—			—			—			(2		)	—			(2		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(33		)	—			(33		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from intercompany investing activities	256			216			44			1,230			(1,746		)	—
Repayments of intercompany investing activities	—			(318		)	(10		)	(81		)	409			—
Net cash provided by (used in) investing activities	256			(109		)	15			1,003			(1,337		)	(172		)
CASH FLOWS FROM FINANCING ACTIVITIES
Repayments of debt	—			(15		)	—			—			—			(15		)
Proceeds from issue of other debt	—			1			—			—			—			1
Repurchase of shares	(100		)	—			—			—			—			(100		)
Proceeds from issue of shares	53			—			—			—			—			53
Excess tax benefits from share-based payment arrangements	—			—			—			2			—			2
Dividends paid	(185		)	—			—			(815		)	815			(185		)
Proceeds from sale of noncontrolling interest	—			—			—			3			—			3
Acquisition of noncontrolling interests	—			—			—			(39		)	—			(39		)
Dividends paid to noncontrolling interests	—			—			—			(11		)	—			(11		)
Cash received on intercompany financing activities	—			81			—			328			(409		)	—
Cash paid on intercompany financing activities	—			(1,462		)	(134		)	(150		)	1,746			—
Net cash used in financing activities	(232		)	(1,395		)	(134		)	(682		)	2,152			(291		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1			—			(163		)	224			—			62
Effect of exchange rate changes on cash and cash equivalents	—			—			—			2			—			2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	—			—			163			273			—			436
CASH AND CASH EQUIVALENTS, END OF YEAR	$	1		$	—		$	—		$	499		$	—		$	500
30	FINANCIAL INFORMATION FOR ISSUER, PARENT GUARANTOR, OTHER GUARANTOR SUBSIDIARIES AND NON-GUARANTOR SUBSIDIARIES
Trinity Acquisition Limited (previously registered as Trinity Acquisition plc) has $525 million senior notes outstanding that were issued on August 15, 2013.
All direct obligations under the senior notes were jointly and severally, irrevocably and fully and unconditionally guaranteed by Willis Netherlands Holdings B.V, Willis Investment UK Holdings Limited, TA I Limited, Willis Group Limited and Willis North America, Inc, collectively the 'Other Guarantors', and with Willis Group Holdings, the 'Guarantor Companies'.
The guarantor structure described above differs from the guarantor structure associated with the senior notes issued by the Company and Willis North America (the ‘Willis North America Debt Securities’) in that Trinity Acquisition Limited is the issuer and not a subsidiary guarantor, and Willis North America, Inc. is a subsidiary guarantor.
Presented below is condensed consolidating financial information for:
(i)	Willis Group Holdings, which is a guarantor, on a parent company only basis;
(ii)	the Other Guarantors, which are all 100 percent directly or indirectly owned subsidiaries of the parent. Willis Netherlands Holdings B.V, Willis Investment UK Holdings Limited and TA I Limited are all direct or indirect parents of the issuer and Willis Group Limited and Willis North America Inc., are 100 percent directly or indirectly owned subsidiaries or the issuer;
(iii)	Trinity Acquisition Limited, which is the issuer and is a 100 percent indirectly owned subsidiary of the parent;
(iv)	Other, which are the non-guarantor subsidiaries, on a combined basis;
(v)	Consolidating adjustments; and
(vi)	the Consolidated Company.
The equity method has been used for investments in subsidiaries in the condensed consolidating balance sheets of Willis Group Holdings, the Other Guarantors and the Issuer.
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	8		$	—		$	3,759		$	—		$	3,767
Investment income	—			—			—			16			—			16
Other income	—			—			—			19			—			19
Total revenues	—			8			—			3,794			—			3,802
EXPENSES
Salaries and benefits	(1		)	(81		)	—			(2,232		)	—			(2,314		)
Other operating expenses	(16		)	(133		)	—			(510		)	—			(659		)
Depreciation expense	—			(21		)	—			(71		)	—			(92		)
Amortization of intangible assets	—			—			—			(54		)	—			(54		)
Restructuring expenses	—			(14		)	—			(22		)	—			(36		)
Total expenses	(17		)	(249		)	—			(2,889		)	—			(3,155		)
OPERATING (LOSS) INCOME	(17		)	(241		)	—			905			—			647
Other (expense) income, net	(15		)	(220		)	—			11			230			6
Income from Group undertakings	—			450			91			102			(643		)	—
Expenses due to Group undertakings	—			(190		)	(29		)	(424		)	643			—
Interest expense	(43		)	(44		)	(36		)	(12		)	—			(135		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(245		)	26			582			230			518
Income taxes	—			54			(5		)	(208		)	—			(159		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(191		)	21			374			230			359
Interest in earnings of associates, net of tax	—			10			—			4			—			14
Equity account for subsidiaries	437			609			314			—			(1,360		)	—
NET INCOME	362			428			335			378			(1,130		)	373
Less: Net income attributable to noncontrolling interests	—			—			—			(11		)	—			(11		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	362		$	428		$	335		$	367		$	(1,130	)	$	362
Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
Comprehensive (loss) income	$	(11	)	$	69		$	(5	)	$	49		$	(108	)	$	(6	)
Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(5		)	—			(5		)
Comprehensive (loss) income attributable to Willis Group Holdings	$	(11	)	$	69		$	(5	)	$	44		$	(108	)	$	(11	)
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	8		$	—		$	3,625		$	—		$	3,633
Investment income	—			—			—			15			—			15
Other income	—			—			—			7			—			7
Total revenues	—			8			—			3,647			—			3,655
EXPENSES
Salaries and benefits	(1		)	(103		)	—			(2,103		)	—			(2,207		)
Other operating expenses	(5		)	(231		)	(1		)	(399		)	—			(636		)
Depreciation expense	—			(23		)	—			(71		)	—			(94		)
Amortization of intangible assets	—			—			—			(55		)	—			(55		)
Total expenses	(6		)	(357		)	(1		)	(2,628		)	—			(2,992		)
OPERATING (LOSS) INCOME	(6		)	(349		)	(1		)	1,019			—			663
Other income (expense), net	5			(4		)	—			31			(10		)	22
Income from Group undertakings	—			491			68			86			(645		)	—
Expenses due to Group undertakings	(10		)	(153		)	(26		)	(456		)	645			—
Loss on extinguishment of debt	—			(60		)	—			—			—			(60		)
Interest expense	(42		)	(61		)	(18		)	(5		)	—			(126		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(136		)	23			675			(10		)	499
Income taxes	—			29			(6		)	(145		)	—			(122		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(107		)	17			530			(10		)	377
Interest in earnings of associates, net of tax	—			9			—			(9		)	—			—
Equity account for subsidiaries	418			515			344			—			(1,277		)	—
NET INCOME	365			417			361			521			(1,287		)	377
Less: Net income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	365		$	417		$	361		$	509		$	(1,287	)	$	365
Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
Comprehensive income	$	522		$	565		$	504		$	636		$	(1,693	)	$	534
Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
Comprehensive income attributable to Willis Group Holdings	$	522		$	565		$	504		$	624		$	(1,693	)	$	522
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	—		$	—		$	3,458		$	—		$	3,458
Investment income	—			1			—			17			—			18
Other income	—			—			—			4			—			4
Total revenues	—			1			—			3,479			—			3,480
EXPENSES
Salaries and benefits	(2		)	(96		)	—			(2,377		)	—			(2,475		)
Other operating expenses	(6		)	(158		)	—			(436		)	—			(600		)
Depreciation expense	—			(16		)	—			(63		)	—			(79		)
Amortization of intangible assets	—			—			—			(59		)	—			(59		)
Goodwill impairment	—			—			—			(492		)	—			(492		)
Total expenses	(8		)	(270		)	—			(3,427		)	—			(3,705		)
OPERATING (LOSS) INCOME	(8		)	(269		)	—			52			—			(225		)
Other income (expense), net	2			(4		)	1			17			—			16
Income from Group undertakings	—			436			79			111			(626		)	—
Expenses due to Group undertakings	—			(185		)	(27		)	(414		)	626			—
Interest expense	(43		)	(69		)	(8		)	(8		)	—			(128		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(49		)	(91		)	45			(242		)	—			(337		)
Income taxes	—			76			(11		)	(166		)	—			(101		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(49		)	(15		)	34			(408		)	—			(438		)
Interest in earnings of associates, net of tax	—			8			—			(3		)	—			5
Equity account for subsidiaries	(397		)	(390		)	(461		)	—			1,248			—
NET LOSS	(446		)	(397		)	(427		)	(411		)	1,248			(433		)
Less: Net income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
NET LOSS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	(446	)	$	(397	)	$	(427	)	$	(424	)	$	1,248		$	(446	)
Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
Comprehensive loss	$	(552	)	$	(494	)	$	(528	)	$	(519	)	$	1,554		$	(539	)
Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
Comprehensive loss attributable to Willis Group Holdings	$	(552	)	$	(494	)	$	(528	)	$	(532	)	$	1,554		$	(552	)
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	9		$	2		$	—		$	624		$	—		$	635
Accounts receivable, net	—			4			—			1,040			—			1,044
Fiduciary assets	—			—			—			8,948			—			8,948
Deferred tax assets	—			—			—			12			—			12
Other current assets	1			41			1			205			(34		)	214
Amounts due from group undertakings	3,674			1,154			797			1,114			(6,739		)	—
Total current assets	3,684			1,201			798			11,943			(6,773		)	10,853
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,478			2,578			—			(6,056		)	—
Fixed assets, net	—			62			—			421			—			483
Goodwill	—			—			—			2,937			—			2,937
Other intangible assets, net	—			—			—			450			—			450
Investments in associates	—			147			—			22			—			169
Deferred tax assets	—			—			—			9			—			9
Pension benefits asset	—			—			—			314			—			314
Other non-current assets	3			2			8			207			—			220
Non-current amounts due from group undertakings	—			740			518			—			(1,258		)	—
Total non-current assets	3			4,429			3,104			4,360			(7,314		)	4,582
TOTAL ASSETS	$	3,687		$	5,630		$	3,902		$	16,303		$	(14,087	)	$	15,435
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,948		$	—		$	8,948
Deferred revenue and accrued expenses	1			34			—			584			—			619
Income taxes payable	—			7			5			55			(34		)	33
Short-term debt and current portion of long-term debt	—			149			17			1			—			167
Deferred tax liabilities	—			—			—			21			—			21
Other current liabilities	67			46			11			320			—			444
Amounts due to group undertakings	—			5,267			576			896			(6,739		)	—
Total current liabilities	68			5,503			609			10,825			(6,773		)	10,232
NON-CURRENT LIABILITIES
Investments in subsidiaries	838			—			—			—			(838		)	—
Long-term debt	796			581			765			—			—			2,142
Liabilities for pension benefits	—			—			—			284			—			284
Deferred tax liabilities	—			—			—			128			—			128
Provisions for liabilities	—			—			—			194			—			194
Other non-current liabilities	—			17			—			372			—			389
Non-current amounts due to group undertakings	—			518			—			740			(1,258		)	—
Total non-current liabilities	1,634			1,116			765			1,718			(2,096		)	3,137
TOTAL LIABILITIES	$	1,702		$	6,619		$	1,374		$	12,543		$	(8,869	)	$	13,369
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REDEEMABLE NONCONTROLLING INTEREST	—			—			—			59			—			59
EQUITY
Total Willis Group Holdings stockholders’ equity	1,985			(989		)	2,528			3,679			(5,218		)	1,985
Noncontrolling interests	—			—			—			22			—			22
Total equity	1,985			(989		)	2,528			3,701			(5,218		)	2,007
TOTAL LIABILITIES AND EQUITY	$	3,687		$	5,630		$	3,902		$	16,303		$	(14,087	)	$	15,435
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	3		$	3		$	—		$	790		$	—		$	796
Accounts receivable, net	—			4			—			1,037			—			1,041
Fiduciary assets	—			—			—			8,412			—			8,412
Deferred tax assets	—			—			—			16			(1		)	15
Other current assets	1			36			1			186			(27		)	197
Amounts due from group undertakings	4,051			975			793			1,484			(7,303		)	—
Total current assets	4,055			1,018			794			11,925			(7,331		)	10,461
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,716			2,705			—			(6,421		)	—
Fixed assets, net	—			66			—			415			—			481
Goodwill	—			—			—			2,838			—			2,838
Other intangible assets, net	—			—			—			353			—			353
Investments in associates	—			156			—			20			—			176
Deferred tax assets	—			—			—			7			—			7
Pension benefits asset	—			—			—			278			—			278
Other non-current assets	4			5			9			188			—			206
Non-current amounts due from group undertakings	—			1,113			518			—			(1,631		)	—
Total non-current assets	4			5,056			3,232			4,099			(8,052		)	4,339
TOTAL ASSETS	$	4,059		$	6,074		$	4,026		$	16,024		$	(15,383	)	$	14,800
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,412		$	—		$	8,412
Deferred revenue and accrued expenses	2			29			—			555			—			586
Income taxes payable	—			4			5			39			(27		)	21
Short-term debt and current portion of long-term debt	—			—			15			—			—			15
Deferred tax liabilities	—			—			—			25			—			25
Other current liabilities	62			42			11			300			—			415
Amounts due to group undertakings	—			5,813			157			1,333			(7,303		)	—
Total current liabilities	64			5,888			188			10,664			(7,330		)	9,474
NON-CURRENT LIABILITIES
Investments in subsidiaries	985			—			—			—			(985		)	—
Long-term debt	795			733			782			1			—			2,311
Liabilities for pension benefits	—			—			—			136			—			136
Deferred tax liabilities	—			1			—			55			—			56
Provisions for liabilities	—			—			—			206			—			206
Other non-current liabilities	—			48			—			326			—			374
Non-current amounts due to group undertakings	—			518			423			690			(1,631		)	—
Total non-current liabilities	1,780			1,300			1,205			1,414			(2,616		)	3,083
TOTAL LIABILITIES	$	1,844		$	7,188		$	1,393		$	12,078		$	(9,946	)	$	12,557
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
EQUITY
Total Willis Group Holdings stockholders’ equity	2,215			(1,114		)	2,633			3,918			(5,437		)	2,215
Noncontrolling interests	—			—			—			28			—			28
Total equity	2,215			(1,114		)	2,633			3,946			(5,437		)	2,243
TOTAL LIABILITIES AND EQUITY	$	4,059		$	6,074		$	4,026		$	16,024		$	(15,383	)	$	14,800
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(35	)	$	781		$	181		$	212		$	(662	)	$	477
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			1			—			6			(1		)	6
Additions to fixed assets	—			(19		)	—			(95		)	1			(113		)
Additions to intangible assets	—			—			—			(4		)	—			(4		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(241		)	—			(241		)
Payments to acquire other investments	—			—			—			(10		)	—			(10		)
Proceeds from sale of operations, net of cash disposed	—			—			—			86			—			86
Proceeds from intercompany investing activities	361			120			—			435			(916		)	—
Repayments of intercompany investing activities	—			(180		)	(4		)	(46		)	230			—
Additional investment in subsidiaries	(31		)	—			—			—			31			—
Net cash provided by (used in) investing activities	330			(78		)	(4		)	131			(655		)	(276		)
CASH FLOWS FROM FINANCING ACTIVITIES
Debt issuance costs	—			—			—			(3		)	—			(3		)
Repayments of debt	—			—			(15		)	—			—			(15		)
Repurchase of shares	(213		)	—			—			—			—			(213		)
Proceeds from issue of shares	134			—			—			31			(31		)	134
Excess tax benefits from share-based payment arrangement	—			—			—			5			—			5
Dividends paid	(210		)	(155		)	(155		)	(352		)	662			(210		)
Acquisition of noncontrolling interests	—			(4		)	—			—			—			(4		)
Dividends paid to noncontrolling interests	—			—			—			(17		)	—			(17		)
Proceeds from intercompany financing activities	—			50			—			180			(230		)	—
Repayments of intercompany financing activities	—			(595		)	(7		)	(314		)	916			—
Net cash used in financing activities	(289		)	(704		)	(177		)	(470		)	1,317			(323		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	6			(1		)	—			(127		)	—			(122		)
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(39		)	—			(39		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3			3			—			790			—			796
CASH AND CASH EQUIVALENTS, END OF YEAR	$	9		$	2		$	—		$	624		$	—		$	635
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH PROVIDED BY OPERATING ACTIVITIES	$	4		$	399		$	63		$	662		$	(567	)	$	561
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			3			—			9			—			12
Additions to fixed assets	—			(18		)	—			(94		)	—			(112		)
Additions to intangible assets	—			—			—			(7		)	—			(7		)
Acquisitions of subsidiaries, net of cash acquired	—			(237		)	—			(30		)	237			(30		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from sale of associates	—			—			—			4			—			4
Proceeds from sale of operations, net of cash disposed	—			—			—			257			(237		)	20
Proceeds from intercompany investing activities	383			160			132			60			(735		)	—
Repayments of intercompany investing activities	(347		)	(120		)	(442		)	(780		)	1,689			—
Net cash provided by (used in) investing activities	36			(212		)	(310		)	(588		)	954			(120		)
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued	—			—			522			—			—			522
Debt issuance costs	—			—			(8		)	—			—			(8		)
Repayments of debt	—			(521		)	(15		)	—			—			(536		)
Tender premium on extinguishment of senior notes	—			(65		)	—			—			—			(65		)
Proceeds from issue of shares	155			—			—			—			—			155
Excess tax benefits from share-based payment arrangement	—			—			—			2			—			2
Dividends paid	(193		)	(230		)	(330		)	(7		)	567			(193		)
Acquisition of noncontrolling interests	—			—			—			(4		)	—			(4		)
Dividends paid to noncontrolling interests	—			—			—			(10		)	—			(10		)
Proceeds from intercompany financing activities	—			1,075			147			467			(1,689		)	—
Repayments of intercompany financing activities	—			(443		)	(69		)	(223		)	735			—
Net cash (used in) provided by financing activities	(38		)	(184		)	247			225			(387		)	(137		)
INCREASE IN CASH AND CASH EQUIVALENTS	2			3			—			299			—			304
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(8		)	—			(8		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	1			—			—			499			—			500
CASH AND CASH EQUIVALENTS, END OF YEAR	$	3		$	3		$	—		$	790		$	—		$	796
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(23	)	$	2,393		$	1,356		$	(97	)	$	(3,104	)	$	525
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			—			5			—			5
Additions to fixed assets	—			(26		)	—			(109		)	—			(135		)
Additions to intangible assets	—			—			—			(2		)	—			(2		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(33		)	—			(33		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from intercompany investing activities	256			176			78			1,230			(1,740		)	—
Repayments of intercompany investing activities	—			(197		)	(131		)	(81		)	409			—
Net cash provided by (used in) investing activities	256			(47		)	(53		)	1,003			(1,331		)	(172		)
CASH FLOWS FROM FINANCING ACTIVITIES
Repayments of debt	—			(4		)	(11		)	—			—			(15		)
Proceeds from issue of other debt	—			—			1			—			—			1
Repurchase of shares	(100		)	—			—			—			—			(100		)
Proceeds from issue of shares	53			—			—			—			—			53
Excess tax benefits from share-based payment arrangements	—			—			—			2			—			2
Dividends paid	(185		)	(1,220		)	(1,069		)	(815		)	3,104			(185		)
Proceeds from sale of noncontrolling interests	—			—			—			3			—			3
Acquisition of noncontrolling interests	—			—			—			(39		)	—			(39		)
Dividends paid to noncontrolling interests	—			—			—			(11		)	—			(11		)
Proceeds from intercompany financing activities	—			81			—			328			(409		)	—
Repayments of intercompany financing activities	—			(1,366		)	(224		)	(150		)	1,740			—
Net cash used in financing activities	(232		)	(2,509		)	(1,303		)	(682		)	4,435			(291		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1			(163		)	—			224			—			62
Effect of exchange rate changes on cash and cash equivalents	—			—			—			2			—			2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	—			163			—			273			—			436
CASH AND CASH EQUIVALENTS, END OF YEAR	$	1		$	—		$	—		$	499		$	—		$	500

Financial_Information_for_Pare1

Financial Information for Parent Issuer, Guarantor Subsidiaries and Non-Guarantor Subsidiaries	12 Months Ended
	Dec. 31, 2014
Financial Information for Parent Issuer Guarantor Subsidiaries and Non-Guarantor Subsidiaries Disclosure [Abstract]
FINANCIAL INFORMATION FOR PARENT ISSUER, GUARANTOR SUBSIDIARIES AND NON-GUARANTOR SUBSIDIARIES
	29	FINANCIAL INFORMATION FOR PARENT ISSUER, GUARANTOR SUBSIDIARIES AND NON-GUARANTOR SUBSIDIARIES
	On March 17, 2011, the Company issued senior notes totaling $800 million in a registered public offering. These debt securities were issued by Willis Group Holdings (‘Holdings Debt Securities’) and are guaranteed by certain of the Company’s subsidiaries. Therefore, the Company is providing the condensed consolidating financial information below. The following 100 percent directly or indirectly owned subsidiaries fully and unconditionally guarantee the Holdings Debt Securities on a joint and several basis: Willis Netherlands Holdings B.V., Willis Investment UK Holdings Limited, TA I Limited, Trinity Acquisition Limited (previously registered as Trinity Acquisition plc), Willis Group Limited and Willis North America (the ‘Guarantors’).
	The guarantor structure described above differs from the guarantor structure associated with the senior notes issued by Willis North America (the ‘Willis North America Debt Securities’) (and for which condensed consolidating financial information is presented in Note 30) in that Willis Group Holdings is the Parent Issuer and Willis North America is a subsidiary guarantor.
	Presented below is condensed consolidating financial information for:
	(i)	Willis Group Holdings, which is the Parent Issuer;
	(ii)	the Guarantors, which are all 100 percent directly or indirectly owned subsidiaries of the parent;
	(iii)	Other, which are the non-guarantor subsidiaries, on a combined basis;
	(iv)	Consolidating adjustments; and
	(v)	the Consolidated Company.
	The equity method has been used for investments in subsidiaries in the condensed consolidating balance sheets for the year ended December 31, 2014 of Willis Group Holdings and the Guarantors.
	Condensed Consolidating Statement of Operations
		Year Ended December 31, 2014
		Willis			The			Other			Consolidating			Consolidated
		Group			Guarantors						adjustments
		Holdings —
		the Parent
		Issuer
		(millions)
	REVENUES
	Commissions and fees	$	—		$	8		$	3,759		$	—		$	3,767
	Investment income	—			—			16			—			16
	Other income	—			—			19			—			19
	Total revenues	—			8			3,794			—			3,802
	EXPENSES
	Salaries and benefits	(1		)	(81		)	(2,232		)	—			(2,314		)
	Other operating expenses	(16		)	(133		)	(510		)	—			(659		)
	Depreciation expense	—			(21		)	(71		)	—			(92		)
	Amortization of intangible assets	—			—			(54		)	—			(54		)
	Restructuring expenses	—			(14		)	(22		)	—			(36		)
	Total expenses	(17		)	(249		)	(2,889		)	—			(3,155		)
	OPERATING (LOSS) INCOME	(17		)	(241		)	905			—			647
	Other (expense) income, net	(15		)	(220		)	11			230			6
	Income from Group undertakings	—			424			102			(526		)	—
	Expenses due to Group undertakings	—			(102		)	(424		)	526			—
	Interest expense	(43		)	(80		)	(12		)	—			(135		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(219		)	582			230			518
	Income taxes	—			49			(208		)	—			(159		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(170		)	374			230			359
	Interest in earnings of associates, net of tax	—			10			4			—			14
	Equity account for subsidiaries	437			588			—			(1,025		)	—
	NET INCOME	362			428			378			(795		)	373
	Less: Net income attributable to noncontrolling interests	—			—			(11		)	—			(11		)
	NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	362		$	428		$	367		$	(795	)	$	362
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2014
		Willis			The Guarantors			Other			Consolidating			Consolidated
		Group									adjustments
		Holdings—the Parent Issuer
		(millions)
	Comprehensive (loss) income	$	(11	)	$	69		$	49		$	(113	)	$	(6	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			(5		)	—			(5		)
	Comprehensive (loss) income attributable to Willis Group Holdings	$	(11	)	$	69		$	44		$	(113	)	$	(11	)
	Condensed Consolidating Statement of Operations
		Year Ended December 31, 2013
		Willis			The			Other			Consolidating			Consolidated
		Group			Guarantors						adjustments
		Holdings —
		the Parent
		Issuer
		(millions)
	REVENUES
	Commissions and fees	$	—		$	8		$	3,625		$	—		$	3,633
	Investment income	—			—			15			—			15
Other income	—			—			7			—			7
Total revenues	—			8			3,647			—			3,655
EXPENSES
Salaries and benefits	(1		)	(103		)	(2,103		)	—			(2,207		)
Other operating expenses	(5		)	(232		)	(399		)	—			(636		)
Depreciation expense	—			(23		)	(71		)	—			(94		)
Amortization of intangible assets	—			—			(55		)	—			(55		)
Total expenses	(6		)	(358		)	(2,628		)	—			(2,992		)
OPERATING (LOSS) INCOME	(6		)	(350		)	1,019			—			663
Other income (expense), net	5			(4		)	31			(10		)	22
Income from Group undertakings	—			466			86			(552		)	—
Expenses due to Group undertakings	(10		)	(86		)	(456		)	552			—
Loss on extinguishment of debt	—			(60		)	—			—			(60		)
Interest expense	(42		)	(79		)	(5		)	—			(126		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(113		)	675			(10		)	499
Income taxes	—			23			(145		)	—			(122		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(90		)	530			(10		)	377
Interest in earnings of associates, net of tax	—			9			(9		)	—			—
Equity account for subsidiaries	418			498			—			(916		)	—
NET INCOME	365			417			521			(926		)	377
Less: Net income attributable to noncontrolling interests	—			—			(12		)	—			(12		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	365		$	417		$	509		$	(926	)	$	365
Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2013
	Willis			The Guarantors			Other			Consolidating			Consolidated
	Group									adjustments
	Holdings—the Parent Issuer
	(millions)
Comprehensive income	$	522		$	565		$	636		$	(1,189	)	$	534
Less: Comprehensive income attributable to noncontrolling interests	—			—			(12		)	—			(12		)
Comprehensive income attributable to Willis Group Holdings	$	522		$	565		$	624		$	(1,189	)	$	522
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2012
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
REVENUES
Commissions and fees	$	—		$	—		$	3,458		$	—		$	3,458
Investment income	—			1			17			—			18
Other income	—			—			4			—			4
Total revenues	—			1			3,479			—			3,480
EXPENSES
Salaries and benefits	(2		)	(96		)	(2,377		)	—			(2,475		)
Other operating expenses	(6		)	(158		)	(436		)	—			(600		)
Depreciation expense	—			(16		)	(63		)	—			(79		)
Amortization of intangible assets	—			—			(59		)	—			(59		)
Goodwill impairment charge	—			—			(492		)	—			(492		)
Total expenses	(8		)	(270		)	(3,427		)	—			(3,705		)
OPERATING (LOSS) INCOME	(8		)	(269		)	52			—			(225		)
Other income (expense), net	2			(3		)	17			—			16
Income from Group undertakings	—			409			111			(520		)	—
Expenses due to Group undertakings	—			(106		)	(414		)	520			—
Interest expense	(43		)	(77		)	(8		)	—			(128		)
LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(49		)	(46		)	(242		)	—			(337		)
Income taxes	—			65			(166		)	—			(101		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(49		)	19			(408		)	—			(438		)
Interest in earnings of associates, net of tax	—			8			(3		)	—			5
Equity account for subsidiaries	(397		)	(424		)	—			821			—
NET LOSS	(446		)	(397		)	(411		)	821			(433		)
Less: Net income attributable to noncontrolling interests	—			—			(13		)	—			(13		)
NET LOSS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	(446	)	$	(397	)	$	(424	)	$	821		$	(446	)
Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2012
	Willis			The Guarantors			Other			Consolidating			Consolidated
	Group									adjustments
	Holdings—the Parent Issuer
	(millions)
Comprehensive loss	$	(552	)	$	(494	)	$	(519	)	$	1,026		$	(539	)
Less: Comprehensive income attributable to noncontrolling interests	—			—			(13		)	—			(13		)
Comprehensive loss attributable to Willis Group Holdings	$	(552	)	$	(494	)	$	(532	)	$	1,026		$	(552	)
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	9		$	2		$	624		$	—		$	635
Accounts receivable, net	—			4			1,040			—			1,044
Fiduciary assets	—			—			8,948			—			8,948
Deferred tax assets	—			—			12			—			12
Other current assets	1			37			205			(29		)	214
Amounts due from group undertakings	3,674			731			1,114			(5,519		)	—
Total current assets	3,684			774			11,943			(5,548		)	10,853
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,528			—			(3,528		)	—
Fixed assets, net	—			62			421			—			483
Goodwill	—			—			2,937			—			2,937
Other intangible assets, net	—			—			450			—			450
Investments in associates	—			147			22			—			169
Deferred tax assets	—			—			9			—			9
Pension benefits asset	—			—			314			—			314
Other non-current assets	3			10			207			—			220
Non-current amounts due from group undertakings	—			740			—			(740		)	—
Total non-current assets	3			4,487			4,360			(4,268		)	4,582
TOTAL ASSETS	$	3,687		$	5,261		$	16,303		$	(9,816	)	$	15,435
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	8,948		$	—		$	8,948
Deferred revenue and accrued expenses	1			34			584			—			619
Income taxes payable	—			7			55			(29		)	33
Short-term debt and current portion on long-term debt	—			166			1			—			167
Deferred tax liabilities	—			—			21			—			21
Other current liabilities	67			57			320			—			444
Amounts due to group undertakings	—			4,623			896			(5,519		)	—
Total current liabilities	68			4,887			10,825			(5,548		)	10,232
NON-CURRENT LIABILITIES
Investments in subsidiaries	838			—			—			(838		)	—
Long-term debt	796			1,346			—			—			2,142
Liabilities for pension benefits	—			—			284			—			284
Deferred tax liabilities	—			—			128			—			128
Provisions for liabilities	—			—			194			—			194
Other non-current liabilities	—			17			372			—			389
Non-current amounts due to group undertakings	—			—			740			(740		)	—
Total non-current liabilities	1,634			1,363			1,718			(1,578		)	3,137
TOTAL LIABILITIES	$	1,702		$	6,250		$	12,543		$	(7,126	)	$	13,369
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
REDEEMABLE NONCONTROLLING INTEREST	—			—			59			—			59
EQUITY
Total Willis Group Holdings stockholders’ equity	1,985			(989		)	3,679			(2,690		)	1,985
Noncontrolling interests	—			—			22			—			22
Total equity	1,985			(989		)	3,701			(2,690		)	2,007
TOTAL LIABILITIES AND EQUITY	$	3,687		$	5,261		$	16,303		$	(9,816	)	$	15,435
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	3		$	3		$	790		$	—		$	796
Accounts receivable, net	—			4			1,037			—			1,041
Fiduciary assets	—			—			8,412			—			8,412
Deferred tax assets	—			—			16			(1		)	15
Other current assets	1			31			186			(21		)	197
Amounts due from group undertakings	4,051			975			1,484			(6,510		)	—
Total current assets	4,055			1,013			11,925			(6,532		)	10,461
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,788			—			(3,788		)	—
Fixed assets, net	—			66			415			—			481
Goodwill	—			—			2,838			—			2,838
Other intangible assets, net	—			—			353			—			353
Investments in associates	—			156			20			—			176
Deferred tax assets	—			—			7			—			7
Pension benefits asset	—			—			278			—			278
Other non-current assets	4			14			188			—			206
Non-current amounts due from group undertakings	—			690			—			(690		)	—
Total non-current assets	4			4,714			4,099			(4,478		)	4,339
TOTAL ASSETS	$	4,059		$	5,727		$	16,024		$	(11,010	)	$	14,800
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	8,412		$	—		$	8,412
Deferred revenue and accrued expenses	2			29			555			—			586
Income taxes payable	—			3			39			(21		)	21
Short-term debt and current portion of long-term debt	—			15			—			—			15
Deferred tax liabilities	—			—			25			—			25
Other current liabilities	62			53			300			—			415
Amounts due to group undertakings	—			5,177			1,333			(6,510		)	—
Total current liabilities	64			5,277			10,664			(6,531		)	9,474
NON-CURRENT LIABILITIES
Investments in subsidiaries	985			—			—			(985		)	—
Long-term debt	795			1,515			1			—			2,311
Liabilities for pension benefits	—			—			136			—			136
Deferred tax liabilities	—			1			55			—			56
Provisions for liabilities	—			—			206			—			206
Other non-current liabilities	—			48			326			—			374
Non-current amounts due to group undertakings	—			—			690			(690		)	—
Total non-current liabilities	1,780			1,564			1,414			(1,675		)	3,083
TOTAL LIABILITIES	$	1,844		$	6,841		$	12,078		$	(8,206	)	$	12,557
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
EQUITY
Total Willis Group Holdings stockholders’ equity	2,215			(1,114		)	3,918			(2,804		)	2,215
Noncontrolling interests	—			—			28			—			28
Total equity	2,215			(1,114		)	3,946			(2,804		)	2,243
TOTAL LIABILITIES AND EQUITY	$	4,059		$	5,727		$	16,024		$	(11,010	)	$	14,800
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2014
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(35	)	$	652		$	212		$	(352	)	$	477
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			1			6			(1		)	6
Additions to fixed assets	—			(19		)	(95		)	1			(113		)
Additions to intangibles assets	—			—			(4		)	—			(4		)
Acquisitions of subsidiaries, net of cash acquired	—			—			(241		)	—			(241		)
Payments to acquire other investments	—			—			(10		)	—			(10		)
Proceeds from disposal of operations, net of cash disposed	—			—			86			—			86
Proceeds from intercompany investing activities	361			120			435			(916		)	—
Repayments of intercompany investing activities	—			(180		)	(46		)	226			—
Additional investment in subsidiaries	(31		)	—			—			31			—
Net cash provided by (used in) investing activities	330			(78		)	131			(659		)	(276		)
CASH FLOWS FROM FINANCING ACTIVITIES
Debt issuance costs	—			—			(3		)	—			(3		)
Repayments of debt	—			(15		)	—			—			(15		)
Repurchase of shares	(213		)	—			—			—			(213		)
Proceeds from the issue of shares	134			—			31			(31		)	134
Excess tax benefits from share-based payment arrangements	—			—			5			—			5
Dividends paid	(210		)	—			(352		)	352			(210		)
Acquisition of noncontrolling interests	—			(4		)	—			—			(4		)
Dividends paid to noncontrolling interests	—			—			(17		)	—			(17		)
Proceeds from intercompany financing activities	—			46			180			(226		)	—
Repayments of intercompany financing activities	—			(602		)	(314		)	916			—
Net cash used in financing activities	(289		)	(575		)	(470		)	1,011			(323		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	6			(1		)	(127		)	—			(122		)
Effect of exchange rate changes on cash and cash equivalents	—			—			(39		)	—			(39		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3			3			790			—			796
CASH AND CASH EQUIVALENTS, END OF YEAR	$	9		$	2		$	624		$	—		$	635
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2013
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES	$	4		$	(98	)	$	662		$	(7	)	$	561
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			3			9			—			12
Additions to fixed assets	—			(18		)	(94		)	—			(112		)
Additions to intangible assets	—			—			(7		)	—			(7		)
Acquisitions of subsidiaries, net of cash acquired	—			(237		)	(30		)	237			(30		)
Payments to acquire other investments	—			—			(7		)	—			(7		)
Proceeds from sale of associates	—			—			4			—			4
Proceeds from sale of operations, net of cash disposed	—			—			257			(237		)	20
Proceeds from intercompany investing activities	383			223			60			(666		)	—
Repayments of intercompany investing activities	(347		)	(120		)	(780		)	1,247			—
Net cash provided by (used in) investing activities	36			(149		)	(588		)	581			(120		)
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued	—			522			—			—			522
Debt issuance costs	—			(8		)	—			—			(8		)
Repayments of debt	—			(536		)	—			—			(536		)
Tender premium on extinguishment of senior notes	—			(65		)	—			—			(65		)
Proceeds from the issue of shares	155			—			—			—			155
Excess tax benefits from share-based payment arrangements	—			—			2			—			2
Dividends paid	(193		)	—			(7		)	7			(193		)
Acquisition of noncontrolling interests	—			—			(4		)	—			(4		)
Dividends paid to noncontrolling interests	—			—			(10		)	—			(10		)
Proceeds from intercompany financing activities	—			780			467			(1,247		)	—
Repayments of intercompany financing activities	—			(443		)	(223		)	666			—
Net cash (used in) provided by financing activities	(38		)	250			225			(574		)	(137		)
INCREASE IN CASH AND CASH EQUIVALENTS	2			3			299			—			304
Effect of exchange rate changes on cash and cash equivalents	—			—			(8		)	—			(8		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	1			—			499			—			500
CASH AND CASH EQUIVALENTS, END OF YEAR	$	3		$	3		$	790		$	—		$	796
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2012
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
NET CASH (USED IN) PROVIDED BY OPERATING	$	(23	)	$	1,460		$	(97	)	$	(815	)	$	525
ACTIVITIES
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			5			—			5
Additions to fixed assets	—			(26		)	(109		)	—			(135		)
Additions to intangible assets	—			—			(2		)	—			(2		)
Acquisitions of subsidiaries, net of cash acquired	—			—			(33		)	—			(33		)
Payments to acquire other investments	—			—			(7		)	—			(7		)
Proceeds from intercompany investing activities	256			150			1,230			(1,636		)	—
Repayments of intercompany investing activities	—			(328		)	(81		)	409			—
Net cash provided by (used in) investing activities	256			(204		)	1,003			(1,227		)	(172		)
CASH FLOWS FROM FINANCING ACTIVITIES
Repayments of debt	—			(15		)	—			—			(15		)
Proceeds from the issue of other debt	—			1			—			—			1
Repurchase of shares	(100		)	—			—			—			(100		)
Proceeds from issue of shares	53			—			—			—			53
Excess tax benefits from share-based payment arrangements	—			—			2			—			2
Dividends paid	(185		)	—			(815		)	815			(185		)
Proceeds from sale of noncontrolling interest	—			—			3			—			3
Acquisition of noncontrolling interests	—			—			(39		)	—			(39		)
Dividends paid to noncontrolling interests	—			—			(11		)	—			(11		)
Proceeds from intercompany financing activities	—			81			328			(409		)	—
Repayments of intercompany financing activities	—			(1,486		)	(150		)	1,636			—
Net cash used in financing activities	(232		)	(1,419		)	(682		)	2,042			(291		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1			(163		)	224			—			62
Effect of exchange rate changes on cash and cash equivalents	—			—			2			—			2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	—			163			273			—			436
CASH AND CASH EQUIVALENTS, END OF YEAR	$	1		$	—		$	499		$	—		$	500

Financial_Information_for_Issu

Financial Information for Issuer, Parent Guarantor, Other Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Notes)	12 Months Ended
	Dec. 31, 2014
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Financial Information of Parent Company Only Disclosure [Text Block]
	28	FINANCIAL INFORMATION FOR PARENT GUARANTOR, OTHER GUARANTOR SUBSIDIARIES AND NON-GUARANTOR SUBSIDIARIES
	Willis North America Inc. (‘Willis North America’) has $148 million senior notes outstanding that were issued on July 1, 2005, $394 million of senior notes issued on March 28, 2007 and $187 million of senior notes issued on September 29, 2009.
	All direct obligations under the senior notes are jointly and severally, irrevocably and fully and unconditionally guaranteed by Willis Netherlands Holdings B.V., Willis Investment UK Holdings Limited, TA I Limited, Trinity Acquisition Limited (previously registered as Trinity Acquisition plc) and Willis Group Limited, collectively the 'Other Guarantors', and with Willis Group Holdings, the 'Guarantor Companies'.
	The debt securities that were issued by Willis North America and guaranteed by the entities described above, and for which the disclosures set forth below relate and are required under applicable SEC rules, were issued under an effective registration statement.
	Presented below is condensed consolidating financial information for:
	(i)	Willis Group Holdings, which is a guarantor, on a parent company only basis;
	(ii)	the Other Guarantors, which are all 100 percent directly or indirectly owned subsidiaries of the parent and are all direct or indirect parents of the issuer;
	(iii)	the Issuer, Willis North America;
	(iv)	Other, which are the non-guarantor subsidiaries, on a combined basis;
	(v)	Consolidating adjustments; and
	(vi)	the Consolidated Company.
	The equity method has been used for investments in subsidiaries in the condensed consolidating balance sheets for the year ended December 31, 2014 of Willis Group Holdings, the Other Guarantors and the Issuer.
	Condensed Consolidating Statement of Operations
		Year Ended December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	REVENUES
	Commissions and fees	$	—		$	—		$	8		$	3,759		$	—		$	3,767
	Investment income	—			—			—			16			—			16
	Other income	—			—			—			19			—			19
	Total revenues	—			—			8			3,794			—			3,802
	EXPENSES
	Salaries and benefits	(1		)	—			(81		)	(2,232		)	—			(2,314		)
	Other operating expenses	(16		)	(95		)	(38		)	(510		)	—			(659		)
	Depreciation expense	—			(4		)	(17		)	(71		)	—			(92		)
	Amortization of intangible assets	—			—			—			(54		)	—			(54		)
	Restructuring costs	—			(11		)	(3		)	(22		)	—			(36		)
	Total expenses	(17		)	(110		)	(139		)	(2,889		)	—			(3,155		)
	OPERATING (LOSS) INCOME	(17		)	(110		)	(131		)	905			—			647
	Other (expense) income, net	(15		)	(220		)	—			11			230			6
	Income from Group undertakings	—			221			313			102			(636		)	—
	Expenses due to Group undertakings	—			(33		)	(179		)	(424		)	636			—
	Interest expense	(43		)	(35		)	(45		)	(12		)	—			(135		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(177		)	(42		)	582			230			518
	Income taxes	—			25			24			(208		)	—			(159		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(152		)	(18		)	374			230			359
	Interest in earnings of associates, net of tax	—			10			—			4			—			14
	Equity account for subsidiaries	437			570			76			—			(1,083		)	—
	NET INCOME	362			428			58			378			(853		)	373
	Less: Net loss attributable to noncontrolling interests	—			—			—			(11		)	—			(11		)
	NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	362		$	428		$	58		$	367		$	(853	)	$	362
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	Comprehensive (loss) income	$	(11	)	$	69		$	(110	)	$	49		$	(3	)	$	(6	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(5		)	—			(5		)
	Comprehensive (loss) income attributable to Willis Group Holdings	$	(11	)	$	69		$	(110	)	$	44		$	(3	)	$	(11	)
	Condensed Consolidating Statement of Operations
		Year Ended December 31, 2013
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	REVENUES
	Commissions and fees	$	—		$	—		$	8		$	3,625		$	—		$	3,633
	Investment income	—			—			—			15			—			15
	Other income	—			—			—			7			—			7
	Total revenues	—			—			8			3,647			—			3,655
EXPENSES
Salaries and benefits	(1		)	—			(103		)	(2,103		)	—			(2,207		)
Other operating expenses	(5		)	(69		)	(163		)	(399		)	—			(636		)
Depreciation expense	—			(3		)	(20		)	(71		)	—			(94		)
Amortization of intangible assets	—			—			—			(55		)	—			(55		)
Total expenses	(6		)	(72		)	(286		)	(2,628		)	—			(2,992		)
OPERATING (LOSS) INCOME	(6		)	(72		)	(278		)	1,019			—			663
Other income (expense), net	5			(4		)	—			31			(10		)	22
Income from Group undertakings	—			191			364			86			(641		)	—
Expenses due to Group undertakings	(10		)	(34		)	(141		)	(456		)	641			—
Loss on extinguishment of debt	—			—			(60		)	—			—			(60		)
Interest expense	(42		)	(16		)	(63		)	(5		)	—			(126		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(53		)	65			(178		)	675			(10		)	499
Income taxes	—			23			—			(145		)	—			(122		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(53		)	88			(178		)	530			(10		)	377
Interest in earnings of associates, net of tax	—			9			—			(9		)	—			—
Equity account for subsidiaries	418			320			150			—			(888		)	—
NET INCOME (LOSS)	365			417			(28		)	521			(898		)	377
Less: Net income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
NET INCOME (LOSS) ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	365		$	417		$	(28	)	$	509		$	(898	)	$	365
Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
Comprehensive income	$	522		$	565		$	74		$	636		$	(1,263	)	$	534
Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
Comprehensive income attributable to Willis Group Holdings	$	522		$	565		$	74		$	624		$	(1,263	)	$	522
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	—		$	—		$	3,458		$	—		$	3,458
Investment income	—			—			1			17			—			18
Other income	—			—			—			4			—			4
Total revenues	—			—			1			3,479			—			3,480
EXPENSES
Salaries and benefits	(2		)	—			(96		)	(2,377		)	—			(2,475		)
Other operating expenses	(6		)	(80		)	(78		)	(436		)	—			(600		)
Depreciation expense	—			(1		)	(15		)	(63		)	—			(79		)
Amortization of intangible assets	—			—			—			(59		)	—			(59		)
Goodwill impairment charge	—			—			—			(492		)	—			(492		)
Total expenses	(8		)	(81		)	(189		)	(3,427		)	—			(3,705		)
OPERATING (LOSS) INCOME	(8		)	(81		)	(188		)	52			—			(225		)
Other income (expense), net	2			(2		)	(1		)	17			—			16
Income from Group undertakings	—			201			316			111			(628		)	—
Expenses due to Group undertakings	—			(67		)	(147		)	(414		)	628			—
Interest expense	(43		)	(7		)	(70		)	(8		)	—			(128		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(49		)	44			(90		)	(242		)	—			(337		)
Income taxes	—			31			34			(166		)	—			(101		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(49		)	75			(56		)	(408		)	—			(438		)
Interest in earnings of associates, net of tax	—			8			—			(3		)	—			5
Equity account for subsidiaries	(397		)	(480		)	(172		)	—			1,049			—
NET LOSS	(446		)	(397		)	(228		)	(411		)	1,049			(433		)
Less: Net income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
NET LOSS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	(446	)	$	(397	)	$	(228	)	$	(424	)	$	1,049		$	(446	)
Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
Comprehensive loss	$	(552	)	$	(494	)	$	(263	)	$	(519	)	$	1,289		$	(539	)
Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
Comprehensive loss attributable to Willis Group Holdings	$	(552	)	$	(494	)	$	(263	)	$	(532	)	$	1,289		$	(552	)
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	9		$	2		$	—		$	624		$	—		$	635
Accounts receivable, net	—			—			4			1,040			—			1,044
Fiduciary assets	—			—			—			8,948			—			8,948
Deferred tax assets	—			—			—			12			—			12
Other current assets	1			27			10			205			(29		)	214
Amounts due from Group undertakings	3,674			924			1,057			1,114			(6,769		)	—
Total current assets	3,684			953			1,071			11,943			(6,798		)	10,853
NON-CURRENT ASSETS
Investments in subsidiaries	—			2,536			721			—			(3,257		)	—
Fixed assets, net	—			20			42			421			—			483
Goodwill	—			—			—			2,937			—			2,937
Other intangible assets, net	—			—			—			450			—			450
Investments in associates	—			147			—			22			—			169
Deferred tax assets	—			—			—			9			—			9
Pension benefits asset	—			—			—			314			—			314
Other non-current assets	3			8			2			207			—			220
Non-current amounts due from Group undertakings	—			518			740			—			(1,258		)	—
Total non-current assets	3			3,229			1,505			4,360			(4,515		)	4,582
TOTAL ASSETS	$	3,687		$	4,182		$	2,576		$	16,303		$	(11,313	)	$	15,435
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,948		$	—		$	8,948
Deferred revenue and accrued expenses	1			4			30			584			—			619
Income taxes payable	—			—			7			55			(29		)	33
Short-term debt and current portion of long-term debt	—			17			149			1			—			167
Deferred tax liabilities	—			—			—			21			—			21
Other current liabilities	67			11			46			320			—			444
Amounts due to Group undertakings	—			4,374			1,499			896			(6,769		)	—
Total current liabilities	68			4,406			1,731			10,825			(6,798		)	10,232
NON-CURRENT LIABILITIES
Investments in subsidiaries	838			—			—			—			(838		)	—
Long-term debt	796			765			581			—			—			2,142
Liabilities for pension benefits	—			—			—			284			—			284
Deferred tax liabilities	—			—			—			128			—			128
Provisions for liabilities	—			—			—			194			—			194
Other non-current liabilities	—			—			17			372			—			389
Non-current amounts due to Group undertakings	—			—			518			740			(1,258		)	—
Total non-current liabilities	1,634			765			1,116			1,718			(2,096		)	3,137
TOTAL LIABILITIES	$	1,702		$	5,171		$	2,847		$	12,543		$	(8,894	)	$	13,369
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REDEEMABLE NONCONTROLLING INTEREST	—			—			—			59			—			59
EQUITY
Total Willis Group Holdings stockholders’ equity	1,985			(989		)	(271		)	3,679			(2,419		)	1,985
Noncontrolling interests	—			—			—			22			—			22
Total equity	1,985			(989		)	(271		)	3,701			(2,419		)	2,007
TOTAL LIABILITIES AND EQUITY	$	3,687		$	4,182		$	2,576		$	16,303		$	(11,313	)	$	15,435
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	3		$	3		$	—		$	790		$	—		$	796
Accounts receivable, net	—			—			4			1,037			—			1,041
Fiduciary assets	—			—			—			8,412			—			8,412
Deferred tax assets	—			—			—			16			(1		)	15
Other current assets	1			21			10			186			(21		)	197
Amounts due by group undertakings	4,051			903			1,317			1,484			(7,755		)	—
Total current assets	4,055			927			1,331			11,925			(7,777		)	10,461
NON-CURRENT ASSETS
Investments in subsidiaries	—			2,838			1,021			—			(3,859		)	—
Fixed assets, net	—			15			51			415			—			481
Goodwill	—			—			—			2,838			—			2,838
Other intangible assets, net	—			—			—			353			—			353
Investments in associates	—			156			—			20			—			176
Deferred tax assets	—			—			—			7			—			7
Pension benefits asset	—			—			—			278			—			278
Other non-current assets	4			9			5			188			—			206
Non-current amounts due by group undertakings	—			518			690			—			(1,208		)	—
Total non-current assets	4			3,536			1,767			4,099			(5,067		)	4,339
TOTAL ASSETS	$	4,059		$	4,463		$	3,098		$	16,024		$	(12,844	)	$	14,800
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,412		$	—		$	8,412
Deferred revenue and accrued expenses	2			1			28			555			—			586
Income taxes payable	—			3			—			39			(21		)	21
Short-term debt and current portion of long-term debt	—			15			—			—			—			15
Deferred tax liabilities	—			—			—			25			—			25
Other current liabilities	62			15			38			300			—			415
Amounts due to group undertakings	—			4,760			1,662			1,333			(7,755		)	—
Total current liabilities	64			4,794			1,728			10,664			(7,776		)	9,474
NON-CURRENT LIABILITIES
Investments in subsidiaries	985			—			—			—			(985		)	—
Long-term debt	795			782			733			1			—			2,311
Liabilities for pension benefits	—			—			—			136			—			136
Deferred tax liabilities	—			1			—			55			—			56
Provisions for liabilities	—			—			—			206			—			206
Other non-current liabilities	—			—			48			326			—			374
Non-current amounts due to group undertakings	—			—			518			690			(1,208		)	—
Total non-current liabilities	1,780			783			1,299			1,414			(2,193		)	3,083
TOTAL LIABILITIES	$	1,844		$	5,577		$	3,027		$	12,078		$	(9,969	)	$	12,557
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
EQUITY
Total Willis Group Holdings stockholders’ equity	2,215			(1,114		)	71			3,918			(2,875		)	2,215
Noncontrolling interests	—			—			—			28			—			28
Total equity	2,215			(1,114		)	71			3,946			(2,875		)	2,243
TOTAL LIABILITIES AND EQUITY	$	4,059		$	4,463		$	3,098		$	16,024		$	(12,844	)	$	14,800
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(35	)	$	387		$	265		$	212		$	(352	)	$	477
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			1			6			(1		)	6
Additions to fixed assets	—			(9		)	(10		)	(95		)	1			(113		)
Additions to intangibles assets	—			—			—			(4		)	—			(4		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(241		)	—			(241		)
Payments to acquire other investments	—			—			—			(10		)	—			(10		)
Proceeds from sale of operations, net of cash disposed	—			—			—			86			—			86
Proceeds from intercompany investing activities	361			—			120			435			(916		)	—
Repayments of intercompany investing activities	—			(53		)	(131		)	(46		)	230			—
Additional investment in subsidiaries	(31		)	—			—			—			31			—
Net cash provided by (used in) investing activities	330			(62		)	(20		)	131			(655		)	(276		)
CASH FLOWS FROM FINANCING ACTIVITIES
Debt issuance costs	—			—			—			(3		)	—			(3		)
Repayments of debt	—			(15		)	—			—			—			(15		)
Repurchase of shares	(213		)	—			—			—			—			(213		)
Proceeds from issue of shares	134			—			—			31			(31		)	134
Excess tax benefits from share-based payment arrangements	—			—			—			5			—			5
Dividends paid	(210		)	—			—			(352		)	352			(210		)
Acquisition of noncontrolling interests	—			(4		)	—			—			—			(4		)
Dividends paid to noncontrolling interests	—			—			—			(17		)	—			(17		)
Proceeds from intercompany financing activities	—			46			4			180			(230		)	—
Repayments of intercompany financing activities	—			(353		)	(249		)	(314		)	916			—
Net cash used in financing activities	(289		)	(326		)	(245		)	(470		)	1,007			(323		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	6			(1		)	—			(127		)	—			(122		)
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(39		)	—			(39		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3			3			—			790			—			796
CASH AND CASH EQUIVALENTS, END OF YEAR	$	9		$	2		$	—		$	624		$	—		$	635
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH PROVIDED BY OPERATING ACTIVITIES	$	4		$	125		$	7		$	662		$	(237	)	$	561
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			3			9			—			12
Additions to fixed assets	—			(7		)	(11		)	(94		)	—			(112		)
Additions to intangible assets	—			—			—			(7		)	—			(7		)
Acquisitions of subsidiaries, net of cash acquired	—			(237		)	(230		)	(30		)	467			(30		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from sale of associates	—			—			—			4			—			4
Proceeds from sale of operations, net of cash disposed	—			—			230			257			(467		)	20
Proceeds from intercompany investing activities	383			211			36			60			(690		)	—
Repayments of intercompany investing activities	(347		)	(442		)	(120		)	(780		)	1,689			—
Net cash provided by (used in) investing activities	36			(475		)	(92		)	(588		)	999			(120		)
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued	—			522			—			—			—			522
Debt issuance costs	—			(8		)	—			—			—			(8		)
Repayments of debt	—			(15		)	(521		)	—			—			(536		)
Tender premium on extinguishment of senior notes	—			—			(65		)	—			—			(65		)
Proceeds from issue of shares	155			—			—			—			—			155
Excess tax benefits from share-based payment arrangements	—			—			—			2			—			2
Dividends paid	(193		)	—			(230		)	(7		)	237			(193		)
Acquisition of noncontrolling interests	—			—			—			(4		)	—			(4		)
Dividends paid to noncontrolling interests	—			—			—			(10		)	—			(10		)
Proceeds from intercompany financing activities	—			321			901			467			(1,689		)	—
Repayments of intercompany financing activities	—			(467		)	—			(223		)	690			—
Net cash (used in) provided by financing activities	(38		)	353			85			225			(762		)	(137		)
INCREASE IN CASH AND CASH EQUIVALENTS	2			3			—			299			—			304
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(8		)	—			(8		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	1			—			—			499			—			500
CASH AND CASH EQUIVALENTS, END OF YEAR	$	3		$	3		$	—		$	790		$	—		$	796
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(23	)	$	1,504		$	(44	)	$	(97	)	$	(815	)	$	525
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			—			5			—			5
Additions to fixed assets	—			(7		)	(19		)	(109		)	—			(135		)
Additions to intangible assets	—			—			—			(2		)	—			(2		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(33		)	—			(33		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from intercompany investing activities	256			216			44			1,230			(1,746		)	—
Repayments of intercompany investing activities	—			(318		)	(10		)	(81		)	409			—
Net cash provided by (used in) investing activities	256			(109		)	15			1,003			(1,337		)	(172		)
CASH FLOWS FROM FINANCING ACTIVITIES
Repayments of debt	—			(15		)	—			—			—			(15		)
Proceeds from issue of other debt	—			1			—			—			—			1
Repurchase of shares	(100		)	—			—			—			—			(100		)
Proceeds from issue of shares	53			—			—			—			—			53
Excess tax benefits from share-based payment arrangements	—			—			—			2			—			2
Dividends paid	(185		)	—			—			(815		)	815			(185		)
Proceeds from sale of noncontrolling interest	—			—			—			3			—			3
Acquisition of noncontrolling interests	—			—			—			(39		)	—			(39		)
Dividends paid to noncontrolling interests	—			—			—			(11		)	—			(11		)
Cash received on intercompany financing activities	—			81			—			328			(409		)	—
Cash paid on intercompany financing activities	—			(1,462		)	(134		)	(150		)	1,746			—
Net cash used in financing activities	(232		)	(1,395		)	(134		)	(682		)	2,152			(291		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1			—			(163		)	224			—			62
Effect of exchange rate changes on cash and cash equivalents	—			—			—			2			—			2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	—			—			163			273			—			436
CASH AND CASH EQUIVALENTS, END OF YEAR	$	1		$	—		$	—		$	499		$	—		$	500
30	FINANCIAL INFORMATION FOR ISSUER, PARENT GUARANTOR, OTHER GUARANTOR SUBSIDIARIES AND NON-GUARANTOR SUBSIDIARIES
Trinity Acquisition Limited (previously registered as Trinity Acquisition plc) has $525 million senior notes outstanding that were issued on August 15, 2013.
All direct obligations under the senior notes were jointly and severally, irrevocably and fully and unconditionally guaranteed by Willis Netherlands Holdings B.V, Willis Investment UK Holdings Limited, TA I Limited, Willis Group Limited and Willis North America, Inc, collectively the 'Other Guarantors', and with Willis Group Holdings, the 'Guarantor Companies'.
The guarantor structure described above differs from the guarantor structure associated with the senior notes issued by the Company and Willis North America (the ‘Willis North America Debt Securities’) in that Trinity Acquisition Limited is the issuer and not a subsidiary guarantor, and Willis North America, Inc. is a subsidiary guarantor.
Presented below is condensed consolidating financial information for:
(i)	Willis Group Holdings, which is a guarantor, on a parent company only basis;
(ii)	the Other Guarantors, which are all 100 percent directly or indirectly owned subsidiaries of the parent. Willis Netherlands Holdings B.V, Willis Investment UK Holdings Limited and TA I Limited are all direct or indirect parents of the issuer and Willis Group Limited and Willis North America Inc., are 100 percent directly or indirectly owned subsidiaries or the issuer;
(iii)	Trinity Acquisition Limited, which is the issuer and is a 100 percent indirectly owned subsidiary of the parent;
(iv)	Other, which are the non-guarantor subsidiaries, on a combined basis;
(v)	Consolidating adjustments; and
(vi)	the Consolidated Company.
The equity method has been used for investments in subsidiaries in the condensed consolidating balance sheets of Willis Group Holdings, the Other Guarantors and the Issuer.
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	8		$	—		$	3,759		$	—		$	3,767
Investment income	—			—			—			16			—			16
Other income	—			—			—			19			—			19
Total revenues	—			8			—			3,794			—			3,802
EXPENSES
Salaries and benefits	(1		)	(81		)	—			(2,232		)	—			(2,314		)
Other operating expenses	(16		)	(133		)	—			(510		)	—			(659		)
Depreciation expense	—			(21		)	—			(71		)	—			(92		)
Amortization of intangible assets	—			—			—			(54		)	—			(54		)
Restructuring expenses	—			(14		)	—			(22		)	—			(36		)
Total expenses	(17		)	(249		)	—			(2,889		)	—			(3,155		)
OPERATING (LOSS) INCOME	(17		)	(241		)	—			905			—			647
Other (expense) income, net	(15		)	(220		)	—			11			230			6
Income from Group undertakings	—			450			91			102			(643		)	—
Expenses due to Group undertakings	—			(190		)	(29		)	(424		)	643			—
Interest expense	(43		)	(44		)	(36		)	(12		)	—			(135		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(245		)	26			582			230			518
Income taxes	—			54			(5		)	(208		)	—			(159		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(191		)	21			374			230			359
Interest in earnings of associates, net of tax	—			10			—			4			—			14
Equity account for subsidiaries	437			609			314			—			(1,360		)	—
NET INCOME	362			428			335			378			(1,130		)	373
Less: Net income attributable to noncontrolling interests	—			—			—			(11		)	—			(11		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	362		$	428		$	335		$	367		$	(1,130	)	$	362
Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
Comprehensive (loss) income	$	(11	)	$	69		$	(5	)	$	49		$	(108	)	$	(6	)
Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(5		)	—			(5		)
Comprehensive (loss) income attributable to Willis Group Holdings	$	(11	)	$	69		$	(5	)	$	44		$	(108	)	$	(11	)
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	8		$	—		$	3,625		$	—		$	3,633
Investment income	—			—			—			15			—			15
Other income	—			—			—			7			—			7
Total revenues	—			8			—			3,647			—			3,655
EXPENSES
Salaries and benefits	(1		)	(103		)	—			(2,103		)	—			(2,207		)
Other operating expenses	(5		)	(231		)	(1		)	(399		)	—			(636		)
Depreciation expense	—			(23		)	—			(71		)	—			(94		)
Amortization of intangible assets	—			—			—			(55		)	—			(55		)
Total expenses	(6		)	(357		)	(1		)	(2,628		)	—			(2,992		)
OPERATING (LOSS) INCOME	(6		)	(349		)	(1		)	1,019			—			663
Other income (expense), net	5			(4		)	—			31			(10		)	22
Income from Group undertakings	—			491			68			86			(645		)	—
Expenses due to Group undertakings	(10		)	(153		)	(26		)	(456		)	645			—
Loss on extinguishment of debt	—			(60		)	—			—			—			(60		)
Interest expense	(42		)	(61		)	(18		)	(5		)	—			(126		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(136		)	23			675			(10		)	499
Income taxes	—			29			(6		)	(145		)	—			(122		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(107		)	17			530			(10		)	377
Interest in earnings of associates, net of tax	—			9			—			(9		)	—			—
Equity account for subsidiaries	418			515			344			—			(1,277		)	—
NET INCOME	365			417			361			521			(1,287		)	377
Less: Net income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	365		$	417		$	361		$	509		$	(1,287	)	$	365
Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
Comprehensive income	$	522		$	565		$	504		$	636		$	(1,693	)	$	534
Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
Comprehensive income attributable to Willis Group Holdings	$	522		$	565		$	504		$	624		$	(1,693	)	$	522
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	—		$	—		$	3,458		$	—		$	3,458
Investment income	—			1			—			17			—			18
Other income	—			—			—			4			—			4
Total revenues	—			1			—			3,479			—			3,480
EXPENSES
Salaries and benefits	(2		)	(96		)	—			(2,377		)	—			(2,475		)
Other operating expenses	(6		)	(158		)	—			(436		)	—			(600		)
Depreciation expense	—			(16		)	—			(63		)	—			(79		)
Amortization of intangible assets	—			—			—			(59		)	—			(59		)
Goodwill impairment	—			—			—			(492		)	—			(492		)
Total expenses	(8		)	(270		)	—			(3,427		)	—			(3,705		)
OPERATING (LOSS) INCOME	(8		)	(269		)	—			52			—			(225		)
Other income (expense), net	2			(4		)	1			17			—			16
Income from Group undertakings	—			436			79			111			(626		)	—
Expenses due to Group undertakings	—			(185		)	(27		)	(414		)	626			—
Interest expense	(43		)	(69		)	(8		)	(8		)	—			(128		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(49		)	(91		)	45			(242		)	—			(337		)
Income taxes	—			76			(11		)	(166		)	—			(101		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(49		)	(15		)	34			(408		)	—			(438		)
Interest in earnings of associates, net of tax	—			8			—			(3		)	—			5
Equity account for subsidiaries	(397		)	(390		)	(461		)	—			1,248			—
NET LOSS	(446		)	(397		)	(427		)	(411		)	1,248			(433		)
Less: Net income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
NET LOSS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	(446	)	$	(397	)	$	(427	)	$	(424	)	$	1,248		$	(446	)
Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
Comprehensive loss	$	(552	)	$	(494	)	$	(528	)	$	(519	)	$	1,554		$	(539	)
Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
Comprehensive loss attributable to Willis Group Holdings	$	(552	)	$	(494	)	$	(528	)	$	(532	)	$	1,554		$	(552	)
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	9		$	2		$	—		$	624		$	—		$	635
Accounts receivable, net	—			4			—			1,040			—			1,044
Fiduciary assets	—			—			—			8,948			—			8,948
Deferred tax assets	—			—			—			12			—			12
Other current assets	1			41			1			205			(34		)	214
Amounts due from group undertakings	3,674			1,154			797			1,114			(6,739		)	—
Total current assets	3,684			1,201			798			11,943			(6,773		)	10,853
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,478			2,578			—			(6,056		)	—
Fixed assets, net	—			62			—			421			—			483
Goodwill	—			—			—			2,937			—			2,937
Other intangible assets, net	—			—			—			450			—			450
Investments in associates	—			147			—			22			—			169
Deferred tax assets	—			—			—			9			—			9
Pension benefits asset	—			—			—			314			—			314
Other non-current assets	3			2			8			207			—			220
Non-current amounts due from group undertakings	—			740			518			—			(1,258		)	—
Total non-current assets	3			4,429			3,104			4,360			(7,314		)	4,582
TOTAL ASSETS	$	3,687		$	5,630		$	3,902		$	16,303		$	(14,087	)	$	15,435
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,948		$	—		$	8,948
Deferred revenue and accrued expenses	1			34			—			584			—			619
Income taxes payable	—			7			5			55			(34		)	33
Short-term debt and current portion of long-term debt	—			149			17			1			—			167
Deferred tax liabilities	—			—			—			21			—			21
Other current liabilities	67			46			11			320			—			444
Amounts due to group undertakings	—			5,267			576			896			(6,739		)	—
Total current liabilities	68			5,503			609			10,825			(6,773		)	10,232
NON-CURRENT LIABILITIES
Investments in subsidiaries	838			—			—			—			(838		)	—
Long-term debt	796			581			765			—			—			2,142
Liabilities for pension benefits	—			—			—			284			—			284
Deferred tax liabilities	—			—			—			128			—			128
Provisions for liabilities	—			—			—			194			—			194
Other non-current liabilities	—			17			—			372			—			389
Non-current amounts due to group undertakings	—			518			—			740			(1,258		)	—
Total non-current liabilities	1,634			1,116			765			1,718			(2,096		)	3,137
TOTAL LIABILITIES	$	1,702		$	6,619		$	1,374		$	12,543		$	(8,869	)	$	13,369
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REDEEMABLE NONCONTROLLING INTEREST	—			—			—			59			—			59
EQUITY
Total Willis Group Holdings stockholders’ equity	1,985			(989		)	2,528			3,679			(5,218		)	1,985
Noncontrolling interests	—			—			—			22			—			22
Total equity	1,985			(989		)	2,528			3,701			(5,218		)	2,007
TOTAL LIABILITIES AND EQUITY	$	3,687		$	5,630		$	3,902		$	16,303		$	(14,087	)	$	15,435
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	3		$	3		$	—		$	790		$	—		$	796
Accounts receivable, net	—			4			—			1,037			—			1,041
Fiduciary assets	—			—			—			8,412			—			8,412
Deferred tax assets	—			—			—			16			(1		)	15
Other current assets	1			36			1			186			(27		)	197
Amounts due from group undertakings	4,051			975			793			1,484			(7,303		)	—
Total current assets	4,055			1,018			794			11,925			(7,331		)	10,461
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,716			2,705			—			(6,421		)	—
Fixed assets, net	—			66			—			415			—			481
Goodwill	—			—			—			2,838			—			2,838
Other intangible assets, net	—			—			—			353			—			353
Investments in associates	—			156			—			20			—			176
Deferred tax assets	—			—			—			7			—			7
Pension benefits asset	—			—			—			278			—			278
Other non-current assets	4			5			9			188			—			206
Non-current amounts due from group undertakings	—			1,113			518			—			(1,631		)	—
Total non-current assets	4			5,056			3,232			4,099			(8,052		)	4,339
TOTAL ASSETS	$	4,059		$	6,074		$	4,026		$	16,024		$	(15,383	)	$	14,800
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,412		$	—		$	8,412
Deferred revenue and accrued expenses	2			29			—			555			—			586
Income taxes payable	—			4			5			39			(27		)	21
Short-term debt and current portion of long-term debt	—			—			15			—			—			15
Deferred tax liabilities	—			—			—			25			—			25
Other current liabilities	62			42			11			300			—			415
Amounts due to group undertakings	—			5,813			157			1,333			(7,303		)	—
Total current liabilities	64			5,888			188			10,664			(7,330		)	9,474
NON-CURRENT LIABILITIES
Investments in subsidiaries	985			—			—			—			(985		)	—
Long-term debt	795			733			782			1			—			2,311
Liabilities for pension benefits	—			—			—			136			—			136
Deferred tax liabilities	—			1			—			55			—			56
Provisions for liabilities	—			—			—			206			—			206
Other non-current liabilities	—			48			—			326			—			374
Non-current amounts due to group undertakings	—			518			423			690			(1,631		)	—
Total non-current liabilities	1,780			1,300			1,205			1,414			(2,616		)	3,083
TOTAL LIABILITIES	$	1,844		$	7,188		$	1,393		$	12,078		$	(9,946	)	$	12,557
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
EQUITY
Total Willis Group Holdings stockholders’ equity	2,215			(1,114		)	2,633			3,918			(5,437		)	2,215
Noncontrolling interests	—			—			—			28			—			28
Total equity	2,215			(1,114		)	2,633			3,946			(5,437		)	2,243
TOTAL LIABILITIES AND EQUITY	$	4,059		$	6,074		$	4,026		$	16,024		$	(15,383	)	$	14,800
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(35	)	$	781		$	181		$	212		$	(662	)	$	477
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			1			—			6			(1		)	6
Additions to fixed assets	—			(19		)	—			(95		)	1			(113		)
Additions to intangible assets	—			—			—			(4		)	—			(4		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(241		)	—			(241		)
Payments to acquire other investments	—			—			—			(10		)	—			(10		)
Proceeds from sale of operations, net of cash disposed	—			—			—			86			—			86
Proceeds from intercompany investing activities	361			120			—			435			(916		)	—
Repayments of intercompany investing activities	—			(180		)	(4		)	(46		)	230			—
Additional investment in subsidiaries	(31		)	—			—			—			31			—
Net cash provided by (used in) investing activities	330			(78		)	(4		)	131			(655		)	(276		)
CASH FLOWS FROM FINANCING ACTIVITIES
Debt issuance costs	—			—			—			(3		)	—			(3		)
Repayments of debt	—			—			(15		)	—			—			(15		)
Repurchase of shares	(213		)	—			—			—			—			(213		)
Proceeds from issue of shares	134			—			—			31			(31		)	134
Excess tax benefits from share-based payment arrangement	—			—			—			5			—			5
Dividends paid	(210		)	(155		)	(155		)	(352		)	662			(210		)
Acquisition of noncontrolling interests	—			(4		)	—			—			—			(4		)
Dividends paid to noncontrolling interests	—			—			—			(17		)	—			(17		)
Proceeds from intercompany financing activities	—			50			—			180			(230		)	—
Repayments of intercompany financing activities	—			(595		)	(7		)	(314		)	916			—
Net cash used in financing activities	(289		)	(704		)	(177		)	(470		)	1,317			(323		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	6			(1		)	—			(127		)	—			(122		)
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(39		)	—			(39		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3			3			—			790			—			796
CASH AND CASH EQUIVALENTS, END OF YEAR	$	9		$	2		$	—		$	624		$	—		$	635
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH PROVIDED BY OPERATING ACTIVITIES	$	4		$	399		$	63		$	662		$	(567	)	$	561
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			3			—			9			—			12
Additions to fixed assets	—			(18		)	—			(94		)	—			(112		)
Additions to intangible assets	—			—			—			(7		)	—			(7		)
Acquisitions of subsidiaries, net of cash acquired	—			(237		)	—			(30		)	237			(30		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from sale of associates	—			—			—			4			—			4
Proceeds from sale of operations, net of cash disposed	—			—			—			257			(237		)	20
Proceeds from intercompany investing activities	383			160			132			60			(735		)	—
Repayments of intercompany investing activities	(347		)	(120		)	(442		)	(780		)	1,689			—
Net cash provided by (used in) investing activities	36			(212		)	(310		)	(588		)	954			(120		)
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued	—			—			522			—			—			522
Debt issuance costs	—			—			(8		)	—			—			(8		)
Repayments of debt	—			(521		)	(15		)	—			—			(536		)
Tender premium on extinguishment of senior notes	—			(65		)	—			—			—			(65		)
Proceeds from issue of shares	155			—			—			—			—			155
Excess tax benefits from share-based payment arrangement	—			—			—			2			—			2
Dividends paid	(193		)	(230		)	(330		)	(7		)	567			(193		)
Acquisition of noncontrolling interests	—			—			—			(4		)	—			(4		)
Dividends paid to noncontrolling interests	—			—			—			(10		)	—			(10		)
Proceeds from intercompany financing activities	—			1,075			147			467			(1,689		)	—
Repayments of intercompany financing activities	—			(443		)	(69		)	(223		)	735			—
Net cash (used in) provided by financing activities	(38		)	(184		)	247			225			(387		)	(137		)
INCREASE IN CASH AND CASH EQUIVALENTS	2			3			—			299			—			304
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(8		)	—			(8		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	1			—			—			499			—			500
CASH AND CASH EQUIVALENTS, END OF YEAR	$	3		$	3		$	—		$	790		$	—		$	796
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(23	)	$	2,393		$	1,356		$	(97	)	$	(3,104	)	$	525
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			—			5			—			5
Additions to fixed assets	—			(26		)	—			(109		)	—			(135		)
Additions to intangible assets	—			—			—			(2		)	—			(2		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(33		)	—			(33		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from intercompany investing activities	256			176			78			1,230			(1,740		)	—
Repayments of intercompany investing activities	—			(197		)	(131		)	(81		)	409			—
Net cash provided by (used in) investing activities	256			(47		)	(53		)	1,003			(1,331		)	(172		)
CASH FLOWS FROM FINANCING ACTIVITIES
Repayments of debt	—			(4		)	(11		)	—			—			(15		)
Proceeds from issue of other debt	—			—			1			—			—			1
Repurchase of shares	(100		)	—			—			—			—			(100		)
Proceeds from issue of shares	53			—			—			—			—			53
Excess tax benefits from share-based payment arrangements	—			—			—			2			—			2
Dividends paid	(185		)	(1,220		)	(1,069		)	(815		)	3,104			(185		)
Proceeds from sale of noncontrolling interests	—			—			—			3			—			3
Acquisition of noncontrolling interests	—			—			—			(39		)	—			(39		)
Dividends paid to noncontrolling interests	—			—			—			(11		)	—			(11		)
Proceeds from intercompany financing activities	—			81			—			328			(409		)	—
Repayments of intercompany financing activities	—			(1,366		)	(224		)	(150		)	1,740			—
Net cash used in financing activities	(232		)	(2,509		)	(1,303		)	(682		)	4,435			(291		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1			(163		)	—			224			—			62
Effect of exchange rate changes on cash and cash equivalents	—			—			—			2			—			2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	—			163			—			273			—			436
CASH AND CASH EQUIVALENTS, END OF YEAR	$	1		$	—		$	—		$	499		$	—		$	500

Quarterly_Financial_Data_Unaud

Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
QUARTERLY FINANCIAL DATA (UNAUDITED)
	31	QUARTERLY FINANCIAL DATA (UNAUDITED)
	Quarterly financial data for 2014 and 2013 were as follows:
		Three Months Ended
		March 31,			June 30,			September 30,			December 31,
		(millions, except per share data)
	2014
	Total revenues	$	1,097		$	935		$	812		$	958
	Total expenses	(771		)	(787		)	(778		)	(819		)
	Net income (loss)	250			48			(8		)	83
	Net income (loss) attributable to Willis Group Holdings	246			47			(7		)	76
	Earnings per share
	— Basic	$	1.37		$	0.26		$	(0.04	)	$	0.43
	— Diluted	$	1.35		$	0.26		$	(0.04	)	$	0.42
	2013
	Total revenues	$	1,051		$	890		$	795		$	919
	Total expenses	(770		)	(723		)	(725		)	(774		)
	Net income (loss)	223			107			(27		)	74
	Net income (loss) attributable to Willis Group Holdings	219			105			(27		)	68
	Earnings per share
	— Basic	$	1.27		$	0.6		$	(0.15	)	$	0.38
	— Diluted	$	1.24		$	0.59		$	(0.15	)	$	0.37

Subsequent_Events_Notes

Subsequent Events (Notes)	12 Months Ended
	Dec. 31, 2014
Subsequent Events [Abstract]
Subsequent Events [Text Block]
	32	SUBSEQUENT EVENTS
	In January, 2015 the Company reached an agreement to acquire a majority interest in Miller Insurance Services LLP, a leading London-based wholesale specialist. The transaction is subject to customary closing conditions and regulatory approval and is expected to close in the second quarter of 2015.

Basis_of_Presentation_and_Sign1

Basis of Presentation and Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements to be Adopted in Future Periods
	In April 2014, the Financial Accounting Standards Board ('FASB') issued Accounting Standards Update ('ASU') No. 2014-08, 'Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity'. This guidance changes the criteria for reporting discontinued operations and enhances the related disclosures around discontinued operations. The new guidance requires a disposal of a component of an entity or a group of components of an entity to be reported in discontinued operations if the disposal represents a strategic shift that has, or will have, a major effect on an entity’s operations and financial results. This guidance is effective for interim and annual periods beginning after December 15, 2014.
	In May 2014, the FASB issued ASU No. 2014-09, 'Revenue From Contracts With Customers'. The new standard supersedes most current revenue recognition guidance and eliminates industry-specific guidance. The ASU is based on the principle that an entity should recognize revenue to depict the transfer of goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The ASU also requires additional disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from customer contracts, including significant judgments and changes in judgments and assets recognized from costs incurred to fulfill a contract. The ASU becomes effective for the Company at the beginning of its 2017 fiscal year; early adoption is not permitted. Entities have the option of using either a full retrospective or a modified retrospective approach for the adoption of the new standard. The Company is currently assessing the impact that this standard will have on its consolidated financial statements.
	In June 2014, the FASB issued guidance on the accounting for stock compensation where share-based payment awards granted to employees required specific performance targets to be achieved in order for employees to become eligible to vest in the awards and such performance targets could be achieved after an employee completes the requisite service period. The amendment in this update requires a performance target that affects vesting and that could be achieved after the requisite service period to be treated as a performance condition. The guidance is applicable to the Company for interim and annual reporting periods beginning after December 15, 2015, although earlier adoption is permitted. The Company is currently assessing the impact that this standard will have on its consolidated financial statements.
	Recent Accounting Pronouncements Adopted During the Period
	In July 2013, the FASB issued ASU No. 2013-11, 'Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists', a consensus of the FASB Emerging Issues Task Force which provides guidance on financial statement presentation of an unrecognized tax benefit when a net operating loss carryforward ('NOL'), or similar tax loss, or a tax credit carryforward exists. Such unrecognized tax benefits are required to be presented as a reduction of a deferred tax asset for a NOL or other tax credit carryforward whenever the NOL or tax credit carryforward would be available to reduce the additional taxable income or tax due if the tax position is disallowed.
	The Company adopted this guidance prospectively from January 1, 2014 and has not applied the amendments to the prior years. Upon adoption in the first quarter of 2014, other non-current liabilities and deferred tax assets were reduced by $21 million.
Principles of Consolidation	Principles of Consolidation
	The accompanying consolidated financial statements include the accounts of Willis Group Holdings and its subsidiaries, which are controlled through the ownership of a majority voting interest. Intercompany balances and transactions have been eliminated on consolidation.
Foreign Currency Translation	Foreign Currency Translation
	Transactions in currencies other than the functional currency of the entity are recorded at the rates of exchange prevailing at the date of the transaction. Monetary assets and liabilities in currencies other than the functional currency are translated at the rates of exchange prevailing at the balance sheet date and the related transaction gains and losses are reported in the statements of operations. Certain intercompany loans are determined to be of a long-term investment nature. The Company records transaction gains and losses from remeasuring such loans as a component of other comprehensive income.
	Upon consolidation, the results of operations of subsidiaries and associates whose functional currency is other than the US dollar are translated into US dollars at the average exchange rate and assets and liabilities are translated at year-end exchange rates. Translation adjustments are presented as a separate component of other comprehensive income in the financial statements and are included in net income only upon sale or liquidation of the underlying foreign subsidiary or associated company.
Use of Estimates	Use of Estimates
	The preparation of financial statements in conformity with US GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities as of the dates of the financial statements and the reported amounts of revenues and expenses during the year. In the preparation of these consolidated financial statements, estimates and assumptions have been made by management concerning: the valuation of intangible assets and goodwill (including those acquired through business combinations); the selection of useful lives of fixed and intangible assets; impairment testing; provisions necessary for accounts receivable, commitments and contingencies and accrued liabilities; long-term asset returns, discount rates and mortality rates in order to estimate pension liabilities and pension expense; income tax valuation allowances; and other similar evaluations. Actual results could differ from the estimates underlying these consolidated financial statements.
Cash and Cash Equivalents	Cash and Cash Equivalents
	Cash and cash equivalents primarily consist of time deposits with original maturities of three months or less.
Fiduciary Assets and Fiduciary Liabilities	Fiduciary Assets and Fiduciary Liabilities
	In its capacity as an insurance agent or broker, the Company collects premiums from insureds and, after deducting its commissions, remits the premiums to the respective insurers; the Company also collects claims or refunds from insurers which it then remits to insureds.
	Fiduciary Assets
	Fiduciary assets comprise Fiduciary Receivables and Fiduciary Funds.
	Fiduciary Receivables
	Fiduciary receivables represent uncollected premiums from insureds and uncollected claims or refunds from insurers.
	Fiduciary Funds
	Fiduciary funds represent unremitted premiums received from insureds and unremitted claims or refunds received from insurers. Fiduciary funds are generally required to be kept in certain regulated bank accounts subject to guidelines which emphasize capital preservation and liquidity. Such funds are not available to service the Company’s debt or for other corporate purposes. Notwithstanding the legal relationships with insureds and insurers, the Company is entitled to retain investment income earned on fiduciary funds in accordance with industry custom and practice and, in some cases, as supported by agreements with insureds.
	The period for which the Company holds such funds is dependent upon the date the insured remits the payment of the premium to the Company, or the date the Company receives refunds from the insurers, and the date the Company is required to forward such payment to the insurer, or insured, respectively.
	In certain instances, the Company advances premiums, refunds or claims to insurance underwriters or insureds prior to collection. Such advances are made from fiduciary funds and are reflected in the accompanying consolidated balance sheets as fiduciary assets.
	Fiduciary Liabilities
	Fiduciary liabilities represent the obligations to remit fiduciary funds and fiduciary receivables to insurers or insureds.
Accounts Receivable	Accounts Receivable
	Accounts receivable are stated at estimated net realizable values. Allowances are recorded, when necessary, in an amount considered by management to be sufficient to meet probable future losses related to uncollectible accounts.
Fixed Assets	Fixed Assets
	Fixed assets are stated at cost less accumulated depreciation. Expenditures for improvements are capitalized; repairs and maintenance are charged to expenses as incurred. Depreciation is computed using the straight-line method based on the estimated useful lives of assets.
	Depreciation on buildings and long leaseholds is calculated over the lesser of 50 years or the lease term. Depreciation on leasehold improvements is calculated over the lesser of the useful life of the assets or the remaining lease term. Depreciation on furniture and equipment is calculated based on a range of 3 to 10 years. Freehold land is not depreciated.
Recoverability of Fixed Assets	Recoverability of Fixed Assets
	Long-lived assets are tested for recoverability whenever events or changes in circumstance indicate that their carrying amounts may not be recoverable. An impairment loss is recognized if the carrying amount of a long-lived asset is not recoverable and exceeds its fair value. Recoverability is determined based on the undiscounted cash flows expected to result from the use and eventual disposition of the asset or asset group. Long-lived assets and certain identifiable intangible assets to be disposed of are reported at the lower of carrying amount or fair value less cost to sell.
Operating Leases	Operating Leases
	Rentals payable on operating leases are charged straight line to expenses over the lease term as the rentals become payable.
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets
	Goodwill represents the excess of the cost of businesses acquired over the fair value of identifiable net assets at the dates of acquisition. The Company reviews goodwill for impairment annually and whenever facts or circumstances indicate that the carrying amounts may not be recoverable. In testing for impairment, the fair value of each reporting unit is compared with its carrying value, including goodwill. If the carrying amount of a reporting unit exceeds its fair value, the amount of an impairment loss, if any, is calculated by comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill.
	Acquired intangible assets are amortized over the following periods:
			Expected
		Amortization basis	life (years)
	Acquired client relationships	In line with underlying cashflows	5 to 20
	Acquired management contracts	Straight line	18
	Other intangible assets	Straight line	3 to 10
	Amortizable intangible assets are reviewed for impairment whenever events or changes in circumstances indicate that their carrying amounts may not be recoverable.
Investments in Associates	Investments in Associates
	Investments are accounted for using the equity method of accounting if the Company has the ability to exercise significant influence, but not control, over the investee. Significant influence is generally deemed to exist if the Company has an equity ownership in the voting stock of the investee between 20 and 50 percent, although other factors, such as representation on the Board of Directors and the impact of commercial arrangements, are considered in determining whether the equity method of accounting is appropriate. Under the equity method of accounting the investment is carried at cost of acquisition, plus the Company’s equity in undistributed net income since acquisition, less any dividends received since acquisition.
	The Company periodically reviews its investments in associates for which fair value is less than cost to determine if the decline in value is other than temporary. If the decline in value is judged to be other than temporary, the cost basis of the investment is written down to fair value. The amount of any write-down is included in the statements of operations as a realized loss.
	All other equity investments where the Company does not have the ability to exercise significant influence are accounted for by the cost method. Such investments are not publicly traded.
Derivative Financial Instruments	Derivative Financial Instruments
	The Company uses derivative financial instruments for other than trading purposes to alter the risk profile of an existing underlying exposure. Interest rate swaps have been used to manage interest risk exposures. Forward foreign currency exchange contracts are used to manage currency exposures arising from future income and expenses. The fair values of derivative contracts are recorded in other assets and other liabilities. The effective portions of changes in the fair value of derivatives that qualify for hedge accounting as cash flow hedges are recorded in other comprehensive income. Amounts are reclassified from other comprehensive income into earnings when the hedged exposure affects earnings. If the derivative is designated as, and qualifies as, an effective fair value hedge, the changes in the fair value of the derivative and of the hedged item attributable to the hedged risk are both recognized in earnings. The amount of hedge ineffectiveness recognized in earnings is based on the extent to which an offset between the fair value of the derivative and hedged item is not achieved. Changes in fair value of derivatives that do not qualify for hedge accounting, together with any hedge ineffectiveness on those that do qualify, are recorded in other operating expenses or interest expense as appropriate.
Income Taxes	Income Taxes
	The Company recognizes deferred tax assets and liabilities for the estimated future tax consequences of events attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating and capital loss and tax credit carry forwards. Deferred tax assets and liabilities are measured using enacted rates in effect for the year in which the differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of changes in tax rates is recognized in the statement of operations in the period in which the change is enacted. Deferred tax assets are reduced through the establishment of a valuation allowance at such time as, based on available evidence, it is more likely than not that the deferred tax assets will not be realized. The Company adjusts valuation allowances to measure deferred tax assets at the amount considered realizable in future periods if the Company’s facts and assumptions change. In making such determination, the Company considers all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax planning strategies and recent financial operations.
	Positions taken in the Company’s tax returns may be subject to challenge by the taxing authorities upon examination. The Company recognizes the benefit of uncertain tax positions in the financial statements when it is more likely than not that the position will be sustained on examination by the tax authorities upon lapse of the relevant statute of limitations, or when positions are effectively settled. The benefit recognized is the largest amount of tax benefit that is greater than 50 percent likely to be realized on settlement with the tax authority, assuming full knowledge of the position and all relevant facts. The Company adjusts its recognition of these uncertain tax benefits in the period in which new information is available impacting either the recognition or measurement of its uncertain tax positions. Such adjustments are reflected as increases or decreases to income taxes in the period in which they are determined.
	The Company recognizes interest and penalties relating to unrecognized tax benefits within income taxes.
Provisions for Liabilities	Provisions for Liabilities
	The Company is subject to various actual and potential claims, lawsuits and other proceedings. The Company records liabilities for such contingencies including legal costs when it is probable that a liability has been incurred before the balance sheet date and the amount can be reasonably estimated. To the extent such losses can be recovered under the Company’s insurance programs, estimated recoveries are recorded when losses for insured events are realized. Significant management judgment is required to estimate the amounts of such contingent liabilities and the related insurance recoveries. The Company analyzes its litigation exposure based on available information, including consultation with outside counsel handling the defense of these matters, to assess its potential liability. Contingent liabilities are not discounted.
Pensions	Pensions
	The Company has two principal defined benefit pension plans which cover approximately half of employees in the United States and United Kingdom. Both these plans are now closed to new entrants. New employees in the United Kingdom are offered the opportunity to join a defined contribution plan and in the United States are offered the opportunity to join a 401(k) plan. In addition to the Company’s UK and US defined benefit pension plans, the Company has several smaller defined benefit pension plans in certain other countries in which it operates including a US non-qualified plan and an unfunded plan in the UK.. Elsewhere, pension benefits are typically provided through defined contribution plans.
	Defined benefit plans
	The net periodic cost of the Company’s defined benefit plans are measured on an actuarial basis using the projected unit credit method and several actuarial assumptions the most significant of which are the discount rate and the expected long-term rate of return on plan assets. Other material assumptions include rates of participant mortality, the expected long-term rate of compensation and pension increases and rates of employee termination. Gains and losses occur when actual experience differs from actuarial assumptions. If such gains or losses exceed ten percent of the greater of plan assets or plan liabilities the Company amortizes those gains or losses over the average remaining service period or average remaining life expectancy as appropriate of the plan participants.
	In accordance with US GAAP the Company records on the balance sheet the funded status of its pension plans based on the projected benefit obligation.
	Defined contribution plans
	Contributions to the Company’s defined contribution plans are recognized as they fall due. Differences between contributions payable in the year and contributions actually paid are shown as either other assets or other liabilities in the consolidated balance sheets.
Share-Based Compensation	Share-Based Compensation
	The Company has equity-based compensation plans that provide for grants of restricted stock units and stock options
	to employees and non-employee directors of the Company who perform services for the Company.
	The Company expenses all equity-based compensation on a straight-line basis over the requisite service period based upon the fair value of the award on the date of grant, the estimated achievement of any performance targets and anticipated staff retention. The awards under equity-based compensation are classified as equity and included as a component of equity on the Company’s consolidated balance sheets, as the ultimate payment of such awards will not be achieved through use of the Company’s cash or other assets.
Revenue Recognition	Revenue Recognition
	Revenue includes insurance commissions, fees for services rendered, certain commissions receivable from insurance carriers, investment income and other income.
	Brokerage income and fees negotiated in lieu of brokerage are recognized at the later of the policy inception date or when the policy placement is complete. Commissions on additional premiums and adjustments are recognized when approved by or agreed between the parties and collectability is reasonably assured.
	Fees for risk management and other services are recognized as the services are provided. Consideration for negotiated fee arrangements for an agreed period covering multiple insurance placements, the provision of risk management and/or other services are allocated to all deliverables on the basis of their relative selling prices. The Company establishes contract cancellation reserves where appropriate: at December 31, 2014, 2013 and 2012, such amounts were not material.
	Investment income is recognized as earned.
	Other income comprises gains on disposal of intangible assets, which primarily arise from settlements through enforcing non-compete agreements in the event of losing accounts through producer defection or the disposal of books of business.

Basis_of_Presentation_and_Sign2

Basis of Presentation and Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Acquired intangible assets are amortized over the following periods:	Acquired intangible assets are amortized over the following periods:
			Expected
		Amortization basis	life (years)
	Acquired client relationships	In line with underlying cashflows	5 to 20
	Acquired management contracts	Straight line	18
	Other intangible assets	Straight line	3 to 10

Employees_Tables

Employees (Tables)	12 Months Ended
	Dec. 31, 2014
Compensation Related Costs [Abstract]
Average number of persons, including Executive Directors, employed by the Company	The average number of persons, including Executive Directors, employed by the Company is as follows:
		Years ended December 31,
		2014			2013			2012
	Total average number of employees for the year	18,200			17,900			17,500
Salaries and benefit expenses	Salaries and benefits expense comprises the following:
		Years ended December 31,
		2014				2013			2012
		(millions)
	Salaries and other compensation awards including amortization and write-off of cash retention awards of $10 million, $6 million and $416 million	$	2,069			$	1,953		$	2,258
	Share-based compensation	52				42			32
	Severance costs	8				32			6
	Social security costs	147				135			133
	Retirement benefits — defined benefit plan (income) expense	(17		)		(4		)	2
	Retirement benefits — defined contribution plan expense	55				49			44
	Total salaries and benefits expense	$	2,314			$	2,207		$	2,475

ShareBased_Compensation_Tables

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Option valuation assumptions
		Years ended December 31,
		2014		2013		2012
	Expected volatility	18.7	%	24.7	%	32.1	%
	Expected dividends	2.8	%	2.6	%	3.2	%
	Expected life (years)	4		4		5
	Risk-free interest rate	1.3	%	1.5	%	0.9	%
Summary of option activity under share based compensation plans	A summary of option activity under the plans at December 31, 2014, and changes during the year then ended is presented below:
				Weighted			Weighted	Aggregate
				Average			Average	Intrinsic
				Exercise			Remaining
							Contractual
	(Options in thousands)	Options		Price(i)			Term	Value
								(millions)
	Time-based stock options
	Balance, beginning of year	7,983		$	35.95
	Granted	1,069		$	41
	Exercised	(2,795	)	$	34.65
	Forfeited	(362	)	$	37.31
	Expired	(212	)	$	36.05
	Balance, end of year	5,683		$	37.45		5 years	$	42
	Options vested or expected to vest at December 31, 2014	5,131		$	37.41		5 years	$	38
	Options exercisable at December 31, 2014	2,712		$	35.84		4 years	$	24
	Performance-based stock options
	Balance, beginning of year	5,260		$	32.8
	Exercised	(1,201	)	$	29.46
	Forfeited	(392	)	$	33.86
	Balance, end of year	3,667		$	33.78		3 years	$	40
	Options vested or expected to vest at December 31, 2014	3,376		$	33.64		3 years	$	38
	Options exercisable at December 31, 2014	2,829		$	32.81		3 years	$	34
	_________________________________
	(i)	Certain options are exercisable in pounds sterling and are converted to dollars using the exchange rate at December 31, 2014.
Summary of restricted stock unit activity under share based compensation plans
				Weighted
				Average
				Grant Date
	(Units awarded in thousands)	Shares		Fair Value
	Nonvested shares (restricted stock units)
	Balance, beginning of year	2,929		$	38.71
	Granted	1,750		$	43.03
	Vested	(858	)	$	37.19
	Forfeited	(327	)	$	37.62
	Balance, end of year	3,494		$	41.35

Restructuring_Costs_Tables

Restructuring Costs (Tables)	12 Months Ended
	Dec. 31, 2014
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Costs [Table Text Block]
		Twelve months ended December 31, 2014
		North America			International			Global			Corporate		Total
		(millions)
	Termination benefits	$	3		$	3		$	10		$	—	$	16
	Professional services and other	—			2			1			17		20
	Total	$	3		$	5		$	11		$	17	$	36
Schedule of Restructuring Reserve by Type of Cost [Table Text Block]
		Termination Benefits			Professional Services and other			Total
		(millions)
	Balance at January 1, 2014	$	—		$	—		$	—
	Charges incurred	16			20			36
	Cash payments	(11		)	(14		)	(25		)
	Balance at December 31, 2014	$	5		$	6		$	11

Auditors_Remuneration_Tables

Auditors' Remuneration (Tables)	12 Months Ended
	Dec. 31, 2014
Auditors' Remuneration [Abstract]
Analysis of auditors' remuneration
		Years ended December 31,
		2014		2013		2012
		(millions)
	Audit of group consolidated financial statements	$	5	$	4	$	4
	Other assurance services	2		3		3
	Other non-audit services	1		1		1
	Total auditors’ remuneration	$	8	$	8	$	8

Other_Expense_Income_Net_Other1

Other (Expense) Income Net Other (Expense) Income Net (Tables)	12 Months Ended
	Dec. 31, 2014
Other Income and Expenses [Abstract]
Other Income Expense Net [Table Text Block]
		Years ended December 31,
		2014			2013		2012
		(millions)
	Gain (loss) on disposal of operations	$	12		$	2	$	(3	)
	Impact of Venezuelan currency devaluation	(14		)	—		—
	Foreign exchange gain	8			20		19
	Other income (expense), net	$	6		$	22	$	16

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Income from continuing operations before income taxes and interest in earnings of associates by location of taxing jurisdiction	An analysis of income from continuing operations before income taxes and interest in earnings of associates by location of the taxing jurisdiction is as follows:
		Years ended December 31,
		2014			2013			2012
		(millions)
	Ireland	$	(65	)	$	(52	)	$	(47	)
	United States	92			(11		)	(615		)
	United Kingdom	154			282			25
	Other jurisdictions	337			280			300
	Income (loss) from continuing operations before income taxes and interest in earnings of associates	$	518		$	499		$	(337	)
Provision for income taxes by location of the taxing jurisdiction	The provision for income taxes by location of the taxing jurisdiction consisted of the following:
		Years ended December 31,
		2014			2013			2012
		(millions)
	Current income taxes:
	US federal tax	$	(16	)	$	7		$	3
	US state and local taxes	7			3			1
	UK corporation tax	29			28			2
	Other jurisdictions	73			45			41
	Total current taxes	93			83			47
	Deferred taxes:
	US federal tax	30			10			(44		)
	US state and local taxes	10			1			(41		)
	Effect of US valuation allowance	5			2			113
	UK corporation tax	24			17			27
	Other jurisdictions	(3		)	9			(1		)
	Total deferred taxes	66			39			54
	Total income taxes	$	159		$	122		$	101
Reconciliation between US federal income taxes at the statutory rate and the Company's provision for income taxes on continuing operations	The reconciliation between US federal income taxes at the statutory rate and the Company’s provision for income taxes on continuing operations is as follows:
		Years ended December 31,
		2014			2013			2012
		(millions, except percentages)
	Income (loss) from continuing operations before income taxes and interest in earnings of associates	$	518		$	499		$	(337	)
	US federal statutory income tax rate	35		%	35		%	35		%
	Income tax expense at US federal tax rate	181			175			(118		)
	Adjustments to derive effective rate:
	Non-deductible expenditure	21			19			15
	Tax impact of internal restructurings	—			11			—
	Movement in provision for unrecognized tax benefits	1			(1		)	6
	Impairment of non-qualifying goodwill	—			—			137
	Disposal of non-qualifying goodwill	11			—			—
	Impact of change in tax rate on deferred tax balances	—			(4		)	(3		)
	Adjustment in respect of prior periods	(2		)	1			6
	Non-deductible Venezuelan foreign exchange loss	5			—			—
	Effect of foreign exchange and other differences	(4		)	1			2
	Changes in valuation allowances applied to deferred tax assets	7			—			114
	Adjustments to eliminate the net tax effect of intra-group items	(30		)	(30		)	(31		)
	Tax differentials of foreign earnings:
	Foreign jurisdictions	(48		)	(54		)	(12		)
	US state taxes and local taxes	17			4			(15		)
	Provision for income taxes	$	159		$	122		$	101
Significant components of deferred income tax assets and liabilities and their balance sheet classifications	The significant components of deferred income tax assets and liabilities and their balance sheet classifications are as follows:
		December 31,
		2014			2013
		(millions)
	Deferred tax assets:
	Accrued expenses not currently deductible	$	133		$	153
	US state net operating losses	76			70
	UK net operating losses	1			3
	Other net operating losses	12			5
	UK capital losses	39			43
	Accrued retirement benefits	109			47
	Deferred compensation	34			37
	Stock options	22			25
	Gross deferred tax assets	426			383
	Less: valuation allowance	(280		)	(196		)
	Net deferred tax assets	$	146		$	187
	Deferred tax liabilities:
	Cost of intangible assets, net of related amortization	$	149		$	120
	Cost of tangible assets, net of related amortization	38			44
	Prepaid retirement benefits	62			56
	Accrued revenue not currently taxable	25			23
	Financial derivative transactions	—			3
	Deferred tax liabilities	274			246
	Net deferred tax (liability) asset	$	(128	)	$	(59	)
		December 31,
		2014			2013
		(millions)
	Balance sheet classifications:
	Current:
	Deferred tax assets	$	12		$	15
	Deferred tax liabilities	(21		)	(25		)
	Net current deferred tax liabilities	(9		)	(10		)
	Non-current:
	Deferred tax assets	9			7
	Deferred tax liabilities	(128		)	(56		)
	Net non-current deferred tax liabilities	(119		)	(49		)
	Net deferred tax liabilities	$	(128	)	$	(59	)
Summary valuation allowances
		Balance at			Additions/			Other movements			Foreign			Balance
		beginning of year			(releases)						exchange differences			at
					charged to									end of year
	Description				costs and expenses
		(millions)
	Year Ended December 31, 2014
	Deferred tax valuation allowance	$	196		$	17		$	67		$	—		$	280
	Year Ended December 31, 2013
	Deferred tax valuation allowance	221			15			(40		)	—			196
	Year Ended December 31, 2012
	Deferred tax valuation allowance	102			110			12			(3		)	221
Reconciliation of the beginning and ending amounts of unrecognized tax benefits	A reconciliation of the beginning and ending amounts of unrecognized tax benefits is as follows:
		2014			2013			2012
		(millions)
	Balance at January 1	$	41		$	37		$	16
	Reductions due to a lapse of the applicable statute of limitation	—			(5		)	(3		)
	Increases for positions taken in current period	5			9			8
	(Decreases) increases for positions taken in prior periods	(26		)	—			16
	Other movements	(1		)	—			—
	Balance at December 31	$	19		$	41		$	37

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Basic and diluted earnings per share
		Years ended December 31,
		2014			2013			2012
		(millions, except per share data)
	Net income (loss) attributable to Willis Group Holdings	$	362		$	365		$	(446	)
	Basic weighted average number of shares outstanding	178			176			173
	Dilutive effect of potentially issuable shares	3			3			—
	Diluted weighted average number of shares outstanding	181			179			173
	Basic earnings per share:
	Net income (loss) attributable to Willis Group Holdings shareholders	$	2.03		$	2.07		$	(2.58	)
	Dilutive effect of potentially issuable shares	(0.03		)	(0.03		)	—
	Diluted earnings per share:
	Net income (loss) attributable to Willis Group Holdings shareholders	$	2		$	2.04		$	(2.58	)

Fixed_Assets_Net_Tables

Fixed Assets, Net (Tables)	12 Months Ended
	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Analysis of fixed asset activity
		Land and			Leasehold			Furniture and			Total
		buildings (i)			improvements			equipment
		(millions)
	Cost: at January 1, 2013	$	78		$	227		$	576		$	881
	Additions	10			22			80			112
	Disposals	—			(7		)	(43		)	(50		)
	Foreign exchange	1			—			5			6
	Cost: at December 31, 2013	89			242			618			949
	Additions	7			25			84			116
	Disposals	—			(12		)	(29		)	(41		)
	Foreign exchange	(3		)	(10		)	(31		)	(44		)
	Cost: at December 31, 2014	$	93		$	245		$	642		$	980
	Depreciation: at January 1, 2013	$	(32	)	$	(75	)	$	(306	)	$	(413	)
	Depreciation expense provided	(3		)	(18		)	(73		)	(94		)
	Disposals	—			6			36			42
	Foreign exchange	(1		)	—			(2		)	(3		)
	Depreciation: at December 31, 2013	(36		)	(87		)	(345		)	(468		)
	Depreciation expense provided	(4		)	(20		)	(68		)	(92		)
	Disposals	—			10			28			38
	Foreign exchange	2			4			19			25
	Depreciation: at December 31, 2014	$	(38	)	$	(93	)	$	(366	)	$	(497	)
	Net book value:
	At December 31, 2013	$	53		$	155		$	273		$	481
	At December 31, 2014	$	55		$	152		$	276		$	483
	_________________________________
	(i)	Included within land and buildings are assets held under capital leases: At December 31, 2014, cost and accumulated depreciation were $32 million and $8 million respectively (2013: $31 million and $6 million, respectively; 2012: $25 million and $4 million respectively). Depreciation in the year ended December 31, 2014 was $2 million (2013: $2 million; 2012: $1 million).

Goodwill_Tables

Goodwill (Tables)	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Changes in the carrying amount of goodwill by operating segment	The changes in the carrying amount of goodwill by reporting unit for the years ended December 31, 2014 and 2013, are as follows:
		Global			North			International			Total
					America
		(millions)
	Balance at January 1, 2013
	Goodwill, gross	$	1,127		$	1,792		$	400		$	3,319
	Accumulated impairment losses	—			(492		)	—			(492		)
	Goodwill, net	1,127			1,300			400			2,827
	Purchase price allocation adjustments	—			(1		)	—			(1		)
	Goodwill acquired during the year	15			—			1			16
	Goodwill disposed of during the year	—			(14		)	—			(14		)
	Other movements	—			(1		)	—			(1		)
	Foreign exchange	3			—			8			11
	Balance at December 31, 2013
	Goodwill, gross	1,145			1,776			409			3,330
	Accumulated impairment losses	—			(492		)	—			(492		)
	Goodwill, net	$	1,145		$	1,284		$	409		$	2,838
	Purchase price allocation adjustments	3			3			7			13
	Goodwill acquired during the year	5			—			179			184
	Goodwill disposed of during the year	—			(48		)	—			(48		)
	Other movements (i)	88			(45		)	(43		)	—
	Foreign exchange	(7		)	—			(43		)	(50		)
	Balance at December 31, 2014
	Goodwill, gross	1,234			1,686			509			3,429
	Accumulated impairment losses	—			(492		)	—			(492		)
	Goodwill, net	$	1,234		$	1,194		$	509		$	2,937
	_________________________________
	(i)	Effective January 1, 2014, the Company changed its internal reporting structure: UK Retail, previously reported within the International segment, is now reported within the Global segment; Mexico Retail, which was previously reported within the North America segment, is now reported in the International segment; and the US captive consulting and facultative reinsurance businesses, both previously reported within the North America segment, are now reported within the Global segment. As a consequence of these changes goodwill has been reallocated between reporting units using the relative fair value allocation approach.

Other_Intangible_Assets_Net_Ta

Other Intangible Assets, Net (Tables)	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Summary of major classes of amortizable intangible assets
		31-Dec-14							31-Dec-13
		Gross carrying		Accumulated			Net carrying amount		Gross carrying		Accumulated			Net carrying amount
		amount		amortization					amount		amortization
		(millions)
	Client relationships	$	689	$	(316	)	$	373	$	671	$	(326	)	$	345
	Management contracts	71		(1		)	70		—		—			—
	Other	11		(4		)	7		14		(6		)	8
	Total amortizable intangible assets	$	771	$	(321	)	$	450	$	685	$	(332	)	$	353
Estimated aggregate amortization of intangible assets for each of the next five years
		(millions)
	2015	$	57
	2016	51
	2017	46
	2018	41
	2019	37
	Thereafter	218
	Total	$	450

Other_Assets_Tables

Other Assets (Tables)	12 Months Ended
	Dec. 31, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Analysis of other assets
		December 31,
		2014		2013
		(millions)
	Other current assets
	Prepayments and accrued income	$	81	$	73
	Income taxes receivable	30		32
	Deferred compensation plan assets	17		26
	Other receivables	86		66
	Total other current assets	$	214	$	197
	Other non-current assets
	Deferred compensation plan assets	$	92	$	88
	Income taxes receivable	—		21
	Accounts receivable, net	29		28
	Other investments	29		19
	Other receivables	70		50
	Total other non-current assets	$	220	$	206
	Total other assets	$	434	$	403

Other_Liabilities_Tables

Other Liabilities (Tables)	12 Months Ended
	Dec. 31, 2014
Other Liabilities Disclosure [Abstract]
Analysis of other liabilities
		December 31,
		2014		2013
		(millions)
	Other current liabilities
	Accounts payable	$	131	$	123
	Accrued dividends payable	55		51
	Other taxes payable	44		51
	Deferred compensation plan liability	17		26
	Other payables	197		164
	Total other current liabilities	$	444	$	415
	Other non-current liabilities
	Incentives from lessors	$	171	$	183
	Deferred compensation plan liability	92		89
	Contingent or deferred consideration on acquisition	26		13
	Accounts payable	14		6
	Income taxes payable	15		40
	Other payables	71		43
	Total other non-current liabilities	$	389	$	374
	Total other liabilities	$	833	$	789

Allowance_for_Doubtful_Account1

Allowance for Doubtful Accounts (Tables)	12 Months Ended
	Dec. 31, 2014
Allowance for Doubtful Accounts [Abstract]
Allowance for doubtful accounts
		Balance at		Additions/		Deductions			Foreign		Balance at
		beginning of year		(releases)		/ Other movements			exchange differences		end of year
				charged to
				costs and expenses
	Description
		(millions)
	Year Ended December 31, 2014
	Allowance for doubtful accounts	$	13	$	4	$	(6	)	$	1	$	12
	Year Ended December 31, 2013
	Allowance for doubtful accounts	$	14	$	3	$	(4	)	$	—	$	13
	Year Ended December 31, 2012
	Allowance for doubtful accounts	$	13	$	16	$	(15	)	$	—	$	14

Pension_Plans_Tables

Pension Plans (Tables)	12 Months Ended
	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Schedule of defined benefit pension plans
		UK Pension Benefits								US Pension Benefits
		2014				2013				2014				2013
		(millions)
	Change in benefit obligation:
	Benefit obligation, beginning of year	$	2,785			$	2,582			$	864			$	958
	Service cost	41				37				—				—
	Interest cost	121				109				40				38
	Employee contributions	2				2				—				—
	Actuarial loss (gain)	390				79				183				(81		)
	Curtailment gain	(2		)		—				—				—
	Benefits paid	(85		)		(78		)		(36		)		(51		)
	Foreign currency changes	(168		)		54				—				—
	Benefit obligations, end of year	3,084				2,785				1,051				864
	Change in plan assets:
	Fair value of plan assets, beginning of year	3,061				2,716				757				708
	Actual return on plan assets	520				255				65				60
	Employee contributions	2				2				—				—
	Employer contributions	91				100				20				40
	Benefits paid	(85		)		(78		)		(36		)		(51		)
	Foreign currency changes	(191		)		66				—				—
	Fair value of plan assets, end of year	3,398				3,061				806				757
	Funded status at end of year	$	314			$	276			$	(245	)		$	(107	)
	Components on the Consolidated Balance Sheets:
	Pension benefits asset	$	314			$	276			$	—			$	—
	Liability for pension benefits	—				—				(245		)		(107		)
Amounts recognized in accumulated other comprehensive loss
		UK Pension Benefits								US Pension Benefits
		2014				2013				2014				2013
						(millions)
	Net actuarial loss	$	809			$	815			$	399			$	233
	Prior service gain	(20		)		(24		)		—				—
Components of the net periodic benefit cost and other amounts
		Years ended December 31,
		UK Pension Benefits												US Pension Benefits
		2014				2013				2012				2014				2013			2012
										(millions)
	Components of net periodic benefit (income) cost:
	Service cost	$	41			$	37			$	35			$	—			$	—		$	—
	Interest cost	121				109				108				40				38			41
	Expected return on plan assets	(213		)		(191		)		(181		)		(54		)		(51		)	(46		)
	Amortization of unrecognized prior service gain and curtailment gain	(4		)		(5		)		(6		)		—				—			—
	Amortization of unrecognized actuarial loss	42				45				39				6				9			8
	Net periodic benefit (income) cost	$	(13	)		$	(5	)		$	(5	)		$	(8	)		$	(4	)	$	3
	Other changes in plan assets and benefit obligations recognized in other comprehensive income (loss):
	Net actuarial loss (gain)	$	83			$	15			$	141			$	172			$	(90	)	$	37
	Amortization of unrecognized actuarial loss	(42		)		(45		)		(39		)		(6		)		(9		)	(8		)
	Amortization of unrecognized prior service gain and curtailment gain	4				5				6				—				—			—
	Curtailment gain	(2		)		—				—				—				—			—
	Total recognized in other comprehensive income (loss)	$	43			$	(25	)		$	108			$	166			$	(99	)	$	29
	Total recognized in net periodic benefit cost and other comprehensive income (loss)	$	30			$	(30	)		$	103			$	158			$	(103	)	$	32
Estimated net loss and prior service cost to be amortized from accumulated other comprehensive loss into net periodic benefit cost
		UK Pension				US Pension
		Benefits				Benefits
		(millions)
	Estimated net loss	$	39			$	11
	Prior service gain	(3		)		—
Schedule of other information concerning defined benefit pension plans
		Years ended December 31,
		UK Pension Benefits						US Pension Benefits
		2014			2013			2014			2013
	Weighted-average assumptions to determine benefit obligations:
	Discount rate	3.6	%		4.4	%		3.9	%		4.8	%
	Rate of compensation increase	2.9	%		3.2	%		N/A			N/A
	Weighted-average assumptions to determine net periodic benefit cost:
	Discount rate	4.4	%		4.4	%		4.8	%		4.1	%
	Expected return on plan assets	7	%		7.3	%		7.3	%		7.3	%
	Rate of compensation increase	3.2	%		2.3	%		N/A			N/A
Pension plan asset allocations based on fair values
			Years ended December 31,
			UK Pension Benefits						US Pension Benefits
	Asset Category		2014			2013			2014			2013
	Equity securities		34	%		36	%		48	%		52	%
	Debt securities		45	%		38	%		49	%		46	%
	Hedge funds		14	%		17	%		—	%		—	%
	Real estate		3	%		3	%		—	%		—	%
	Cash		4	%		6	%		—	%		—	%
	Other		—	%		—	%		3	%		2	%
	Total		100	%		100	%		100	%		100	%
Changes in the UK pension plan's Level 3 assets
		UK Pension
		Plan
		Level 3
		(millions)
	Balance at January 1, 2013	$	507
	Purchases, sales, issuances and settlements, net	121
	Unrealized and realized gains relating to instruments still held at end of year	29
	Foreign exchange	12
	Balance at December 31, 2013	$	669
	Purchases, sales, issuances and settlements, net	40
	Unrealized and realized gains relating to instruments still held at end of year	24
	Foreign exchange	(23		)
	Balance at December 31, 2014	$	710
Expected future benefit payments
	Expected future benefit payments		UK Pension Benefits			US Pension Benefits
			(millions)
	2015		83			41
	2016		84			43
	2017		87			46
	2018		89			49
	2019		92			51
	2019-2023		505			284
UK Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
			UK Pension Plan
	31-Dec-14		Level 1				Level 2				Level 3				Total
							(millions)
	Equity securities:
	US equities		$	565			$	185			$	—			$	750
	UK equities		234				15				—				249
	Other equities		26				124				—				150
	Fixed income securities:
	US Government bonds		81				2				—				83
	UK Government bonds		783				6				—				789
	Other Government bonds		3				3				99				105
	UK corporate bonds		—				103				—				103
	Other corporate bonds		113				33				—				146
	Derivatives		—				293				—				293
	Real estate		—				—				124				124
	Cash and cash equivalents		124				13				—				137
	Other investments:
	Hedge funds		—				—				487				487
	Other		—				(18		)		—				(18		)
	Total		$	1,929			$	759			$	710			$	3,398
			UK Pension Plan
	31-Dec-13		Level 1				Level 2				Level 3				Total
							(millions)
	Equity securities:
	US equities		$	659			$	81			$	—			$	740
	UK equities		239				17				—				256
	Other equities		40				63				—				103
	Fixed income securities:
	US Government bonds		31				—				—				31
	UK Government bonds		656				—				—				656
	Other Government bonds		7				—				100				107
	UK corporate bonds		75				—				—				75
	Other corporate bonds		151				—				—				151
	Derivatives		—				154				—				154
	Real estate		—				—				92				92
	Cash and cash equivalents		163				—				—				163
	Other investments:
	Hedge funds		—				28				477				505
	Other		—				28				—				28
	Total		$	2,021			$	371			$	669			$	3,061
US Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
			US Pension Plan
	31-Dec-14		Level 1				Level 2				Level 3				Total
							(millions)
	Equity securities:
	US equities		$	115			$	117			$	—			$	232
	Non US equities		110				44				—				154
	Fixed income securities:
	US Government bonds		—				72				—				72
	US corporate bonds		—				171				—				171
	International fixed income securities		59				42				—				101
	Municipal & Non US government bonds		—				32				—				32
	Other investments:
	Mortgage backed securities		—				16				—				16
	Other		20				8				—				28
	Total		$	304			$	502			$	—			$	806
			US Pension Plan
	31-Dec-13		Level 1				Level 2				Level 3				Total
							(millions)
	Equity securities:
	US equities		$	120			$	125			$	—			$	245
	Non US equities		116				33				—				149
	Fixed income securities:
	US Government bonds		—				55				—				55
	US corporate bonds		—				151				—				151
	International fixed income securities		58				42				—				100
	Municipal & Non US government bonds		—				30				—				30
	Other investments:
	Mortgage backed securities		—				12				—				12
	Other		9				6				—				15
	Total		$	303			$	454			$	—			$	757
International Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Schedule of defined benefit pension plans
		Other defined benefit plans
		2014				2013
		(millions)
	Change in benefit obligation:
	Benefit obligation, beginning of year	$	195			$	180
	Service cost	3				3
	Interest cost	7				7
	Actuarial loss (gain)	38				(5		)
	Benefits paid	(9		)		(6		)
	Reclassification from other non-current liabilities (i)	—				10
	Foreign currency changes	(24		)		6
	Benefit obligations, end of year	210				195
	Change in plan assets:
	Fair value of plan assets, beginning of year	168				150
	Actual return on plan assets	25				9
	Employer contributions	11				10
	Benefits paid	(9		)		(6		)
	Foreign currency changes	(24		)		5
	Fair value of plan assets, end of year	171				168
	Funded status at end of year	$	(39	)		$	(27	)
	Components on the Consolidated Balance Sheets:
	Pension benefits asset	$	—			$	2
	Liability for pension benefits	$	(39	)		$	(29	)
	_________________________________
	(i)	Represents the transfer in of the benefit obligation for UK unfunded plan from non-current other liabilities.
Amounts recognized in accumulated other comprehensive loss
		Other defined benefit plans
		2014				2013				2012
		(millions)
	Components of net periodic benefit cost:
	Service cost	$	3			$	3			$	3
	Interest cost	7				7				7
	Expected return on plan assets	(6		)		(6		)		(6		)
	Amortization of unrecognized actuarial loss	—				1				—
	Net periodic benefit cost	$	4			$	5			$	4
	Other changes in plan assets and benefit obligations recognized in other comprehensive income (loss):
	Amortization of unrecognized actuarial loss	$	—			$	(1	)		$	—
	Net actuarial loss (gain)	19				(8		)		25
	Total recognized in other comprehensive loss (income)	19				(9		)		25
	Total recognized in net periodic benefit cost and other comprehensive loss (income)	$	23			$	(4	)		$	29
Schedule of other information concerning defined benefit pension plans
		Other defined benefit plans
		2014		2013
	Weighted-average assumptions to determine benefit obligations:
	Discount rate	2.00% - 3.60%		3.30% - 4.40%
	Rate of compensation increase	2.00% - 3.50%		2.00% - 2.50%
	Weighted-average assumptions to determine net periodic benefit cost:
	Discount rate	3.30% - 4.40%		2.50% - 4.40%
	Expected return on plan assets	2.00% - 4.66%		2.00% - 4.66%
	Rate of compensation increase	2.00% - 2.50%		2.00% - 2.50%
Pension plan asset allocations based on fair values
			Other defined benefit plans
	Asset Category		2014			2013
	Equity securities		24	%		35	%
	Debt securities		40	%		39	%
	Real estate		3	%		3	%
	Derivatives		13	%		14	%
	Other		20	%		9	%
	Total		100	%		100	%
			Other defined benefit plans
	31-Dec-14		Level 1				Level 2				Level 3				Total
							(millions)
	Equity securities:
	US equities		$	18			$	—			$	—			$	18
	UK equities		4				—				—				4
	Overseas equities		18				—				—				18
	Fixed income securities:
	Other Government bonds		65				—				—				65
	Corporate bonds		4				—				—				4
	Derivative instruments		—				23				—				23
	Real estate		—				—				6				6
	Cash		11				—				—				11
	Other investments:
	Other investments		14				—				8				22
	Total		$	134			$	23			$	14			$	171
			Other defined benefit plans
	31-Dec-13		Level 1				Level 2				Level 3				Total
							(millions)
	Equity securities:
	US equities		$	29			$	—			$	—			$	29
	UK equities		5				—				—				5
	Overseas equities		26				—				—				26
	Fixed income securities:
	Other Government bonds		61				—				—				61
	Corporate bonds		4				—				—				4
	Derivative instruments		—				23				—				23
	Real estate		—				—				5				5
	Cash		8				—				—				8
	Other investments:
	Other investments		—				—				7				7
	Total		$	133			$	23			$	12			$	168
Expected future benefit payments
			Other defined benefit plans
			Pension
	Expected future benefit payments		Benefits
			(millions)
	2015		$	5
	2016		6
	2017		6
	2018		6
	2019		6
	2019-2023		32

Debt_Tables

Debt (Tables)	12 Months Ended
	Dec. 31, 2014
Debt Disclosure [Abstract]
Short term debt and current portion of long-term debt
		December 31,
		2014		2013
		(millions)
	Current portion of 7-year term loan facility expires 2018	$	17	$	15
	5.625% senior notes due 2015	148		—
	Fair value adjustment on 5.625% senior notes due 2015	1		—
	3-year term loan facility expires 2015	1		—
		$	167	$	15
Long-term debt
		December 31,
		2014		2013
		(millions)
	7-year term loan facility expires 2018	$	242	$	259
	5.625% senior notes due 2015	—		148
	Fair value adjustment on 5.625% senior notes due 2015	—		4
	4.125% senior notes due 2016	299		299
	6.200% senior notes due 2017	394		394
	7.000% senior notes due 2019	187		187
	5.750% senior notes due 2021	497		496
	4.625% senior notes due 2023	249		249
	6.125% senior notes due 2043	274		274
	3-year term loan facility expires 2015	—		1
		$	2,142	$	2,311
Analysis of interest expense
		Year ended December 31,
		2014		2013		2012
		(millions)
	5.625% senior notes due 2015	$	8	$	12	$	12
	4.125% senior notes due 2016	13		13		13
	6.200% senior notes due 2017	25		33		38
	7.000% senior notes due 2019	14		18		21
	5.750% senior notes due 2021	30		29		29
	4.625% senior notes due 2023	11		4		—
	6.125% senior notes due 2043	16		6		—
	7-year term loan facility expires 2018	5		6		6
	Revolving $800 million credit facility	3		2		1
	Revolving $400 million credit facility	4		—		—
	Other	6		3		8
	Total interest expense	$	135	$	126	$	128

Provisions_for_Liabilities_Tab

Provisions for Liabilities (Tables)	12 Months Ended
	Dec. 31, 2014
Provisions for Liabilities [Abstract]
Analysis of movements on provisions for liabilities
		Claims,			Other			Total
		lawsuits and			provisions(ii)
		other
		proceedings(i)
					(millions)
	Balance at January 1, 2013	$	152		$	28		$	180
	Net provisions made during the year	28			6			34
	Balances transferred in during the year (iii)	—			13			13
	Utilized in the year	(17		)	(6		)	(23		)
	Foreign currency translation adjustment	1			1			2
	Balance at December 31, 2013	$	164		$	42		$	206
	Net provisions made during the year	19			5			24
	Balances transferred in during the year (iv)	—			5			5
	Utilized in the year	(31		)	(3		)	(34		)
	Foreign currency translation adjustment	(4		)	(3		)	(7		)
	Balance at December 31, 2014	$	148		$	46		$	194
	_________________________________
	(i)	The claims, lawsuits and other proceedings provision includes E&O cases which represents management’s assessment of liabilities that may arise from asserted and unasserted claims for alleged errors and omissions that arise in the ordinary course of the Group’s business. Where some of the potential liability is recoverable under the Group’s external insurance arrangements, the full assessment of the liability is included in the provision with the associated insurance recovery shown separately as an asset.
	(ii)	The ‘Other’ category includes amounts relating to vacant property provisions of $4 million (2013: $10 million).
	(iii)	Provisions held in the UK for ongoing post placement services, long term disability and legal claims all previously recognized within Deferred Revenue and Accrued Expenses were transferred to Provisions for Liabilities during 2013.
	(iv)	Provisions held in the UK for dilapidation on UK properties all previously recognized within Deferred Revenue and Accrued Expenses were transferred to Provisions for Liabilities during 2014.

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Contractual obligations
		Payments due by
	Obligations (iii)	Total		2015			2016-2017		2018-2019		After 2019
		(millions)
	7-year term loan facility expires 2018	$	259	$	17		$	45	$	197	$	—
	Interest on term loan	14		4			8		2		—
	Revolving $800 million credit facility commitment fees	7		2			4		1		—
	Revolving $400 million credit facility commitment fees	2		1			1		—		—
	5.625% senior notes due 2015	148		148			—		—		—
	4.125% senior notes due 2016	300		—			300		—		—
	6.200% senior notes due 2017	394		—			394		—		—
	7.000% senior notes due 2019	187		—			—		187		—
	5.750% senior notes due 2021	500		—			—		—		500
	4.625% senior notes due 2023	250		—			—		—		250
	6.125% senior notes due 2043	275		—			—		—		275
	Interest on senior notes	896		112			173		137		474
	Total debt and related interest	3,232		284			925		524		1,499
	Operating leases(i)	1,181		128			221		175		657
	Pensions	346		116			190		40		—
	Other contractual obligations(ii)	143		10			40		43		50
	Acquisition liabilities	51		8			27		16		—
	Total contractual obligations	$	4,953	$	546		$	1,403	$	798	$	2,206
	_________________________________
	(i)	Presented gross of sublease income.
	(ii)	Other contractual obligations include capital lease commitments, put option obligations and investment fund capital call obligations, the timing of which are included at the earliest point they may fall due.
	(iii)	The above excludes $19 million of liabilities for unrecognized tax benefits as the Company is unable to reasonably predict the timing of settlement of these liabilities
Future minimum rental commitments under all non-cancellable operating lease agreements
		Gross rental		Rentals from			Net rental
		commitments		subleases			commitments
				(millions)
	2015	$	128	$	(13	)	$	115
	2016	115		(13		)	102
	2017	106		(12		)	94
	2018	91		(7		)	84
	2019	84		(5		)	79
	Thereafter	657		(10		)	647
	Total	$	1,181	$	(60	)	$	1,121

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Loss, Net of Tax (Tables)	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Components of comprehensive income (loss)	The components of other comprehensive (loss) income are as follows:
		31-Dec-14												31-Dec-13									31-Dec-12
		Before tax amount				Tax				Net of tax amount				Before tax amount			Tax			Net of tax amount			Before tax amount			Tax			Net of tax amount
		(millions)
	Other comprehensive (loss) income:
	Foreign currency translation adjustments	$	(183	)		$	—			$	(183	)		$	20		$	—		$	20		$	46		$	—		$	46
	Pension funding adjustments:
	Foreign currency translation on pension funding adjustments	49				(12		)		37				(15		)	5			(10		)	(31		)	9			(22		)
	Net actuarial (loss) gain	(274		)		19				(255		)		83			2			85			(203		)	36			(167		)
	Amortization of unrecognized actuarial loss	48				(8		)		40				55			(9		)	46			47			(9		)	38
	Amortization of unrecognized prior service gain and curtailment gain	(4		)		1				(3		)		(5		)	1			(4		)	(6		)	1			(5		)
	Curtailment gain	2				—				2				—			—			—			—			—			—
		(179		)		—				(179		)		118			(1		)	117			(193		)	37			(156		)
	Derivative instruments:
	Gain on interest rate swaps (effective element)	—				—				—				—			—			—			3			(1		)	2
	Interest rate reclassification adjustment	(5		)		1				(4		)		(5		)	1			(4		)	(5		)	1			(4		)
	(Loss) gain on forward exchange contracts (effective element)	(31		)		6				(25		)		10			(2		)	8			11			(2		)	9
	Forward exchange contract reclassification adjustment	16				(3		)		13				1			—			1			(4		)	1			(3		)
	Gain on treasury lock (effective element)	—				—				—				19			(4		)	15			—			—			—
	Treasury lock reclassification adjustment	(1		)		—				(1		)		—			—			—			—			—			—
		(21		)		4				(17		)		25			(5		)	20			5			(1		)	4
	Other comprehensive (loss) income	(383		)		4				(379		)		163			(6		)	157			(142		)	36			(106		)
	Less: Other comprehensive loss attributable to noncontrolling interests	6				—				6				—			—			—			—			—			—
	Other comprehensive (loss) income attributable to Willis Group Holdings	$	(377	)		$	4			$	(373	)		$	163		$	(6	)	$	157		$	(142	)	$	36		$	(106	)
Components of accumulated other comprehensive loss, net of tax
		Net foreign currency translation adjustment				Pension funding adjustment				Net unrealized gain on derivative instruments				Total
		(millions)
	Balance, December 31, 2011	$	(80	)		$	(675	)		$	11			$	(744	)
	Other comprehensive income (loss) before reclassifications	46				(189		)		11				(132		)
	Amounts reclassified from accumulated other comprehensive income	—				33				(7		)		26
	Net current year other comprehensive income (loss), net of tax and noncontrolling interests	46				(156		)		4				(106		)
	Balance, December 31, 2012	$	(34	)		$	(831	)		$	15			$	(850	)
	Other comprehensive income before reclassifications	20				75				23				118
	Amounts reclassified from accumulated other comprehensive income	—				42				(3		)		39
	Net current year other comprehensive income, net of tax and noncontrolling interests	20				117				20				157
	Balance, December 31, 2013	$	(14	)		$	(714	)		$	35			$	(693	)
	Other comprehensive loss before reclassifications	(177		)		(216		)		(25		)		(418		)
	Amounts reclassified from accumulated other comprehensive income	—				37				8				45
	Net current year other comprehensive loss, net of tax and noncontrolling interests	(177		)		(179		)		(17		)		(373		)
	Balance, December 31, 2014	$	(191	)		$	(893	)		$	18			$	(1,066	)
Schedule of amounts reclassified out of accumulated other comprehensive income	Amounts reclassified out of accumulated other comprehensive income into the statement of operations are as follows:
	Details about accumulated other comprehensive income components		Amount reclassified from accumulated other comprehensive income												Affected line item in the statement of operations
			Years ended December 31,
			2014				2013				2012
			(millions)
	Gains and losses on cash flow hedges (Note 24)
	Interest rate swaps		$	(5	)		$	(5	)		$	(5	)		Investment income
	Foreign exchange contracts		16				1				(4		)		Other income (expense), net
	Treasury lock		(1		)		—				—				Interest expense
			10				(4		)		(9		)		Total before tax
	Tax		(2		)		1				2
			$	8			$	(3	)		$	(7	)		Net of tax
	Amortization of defined benefit pension items (Note 17)
	Prior service gain and curtailment gain		$	(4	)		$	(5	)		$	(6	)		Salaries and benefits
	Net actuarial loss		48				55				47				Salaries and benefits
			44				50				41				Total before tax
	Tax		(7		)		(8		)		(8		)
			$	37			$	42			$	33			Net of tax
	Total reclassifications for the period		$	45			$	39			$	26

Equity_and_Noncontrolling_Inte1

Equity and Noncontrolling Interest (Tables)	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Effects of changes in ownership interest in subsidiaries
		Years ended December 31,
		2014		2013			2012
				(millions)
	Net income (loss) attributable to Willis Group Holdings	$	362	$	365		$	(446	)
	Transfers from noncontrolling interest:
	Decrease in Willis Group Holdings’ paid-in capital for purchase of noncontrolling interest	—		(4		)	(31		)
	Increase in Willis Group Holdings’ paid-in capital for sale of noncontrolling interest	—		—			2
	Net transfers from noncontrolling interest	—		(4		)	(29		)
	Change from net income (loss) attributable to Willis Group Holdings and transfers from noncontrolling interests	$	362	$	361		$	(475	)

Supplemental_Disclosures_of_Ca1

Supplemental Disclosures of Cash Flow Information (Tables)	12 Months Ended
	Dec. 31, 2014
Supplemental Cash Flow Elements [Abstract]
Supplemental disclosures regarding cash flow information and non-cash flow investing and financing activities
		Years Ended December 31,
		2014		2013			2012
		(millions)
	Supplemental disclosures of cash flow information:
	Cash payments for income taxes, net	$	88	$	61		$	63
	Cash payments for interest	123		117			118
	Supplemental disclosures of non-cash investing and financing activities:
	Write-off of unamortized debt issuance costs	$	—	$	(2	)	$	—
	Write-back of fair value adjustment on 5.625% senior notes due 2015	—		7			—
	Assets acquired under capital leases	3		7			2
	Deferred payments on acquisitions of subsidiaries	10		2			4
	Acquisitions:
	Fair value of assets acquired	$	296	$	47		$	23
	Less:
	Liabilities assumed	107		30			3
	Cash acquired	57		1			—
	Net assets acquired, net of cash acquired	$	132	$	16		$	20

Derivative_Financial_Instrumen1

Derivative Financial Instruments and Hedging Activities (Tables)	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Foreign currency risk
		December 31,
		Sell				Sell
		2014(i)				2013
		(millions)
	US dollar	$	678			$	303
	Euro	186				97
	Japanese yen	51				35
	_________________________________
	(i)	Forward exchange contracts range in maturity from 2015 to 2017.
Derivative financial and hedging instruments
				Fair value
		Balance sheet		December 31,				December 31,
	Derivative financial instruments designated as hedging instruments:	classification		2014				2013
				(millions)
	Assets:
	Forward exchange contracts	Other assets		26				23
	Total derivatives designated as hedging instruments			$	26			$	23
	Liabilities:
	Forward exchange contracts	Other liabilities		21				2
	Total derivatives designated as hedging instruments			$	21			$	2
Derivatives in cash flow hedging relationships
	Derivatives in cash flow hedging relationships	Amount of				Location of gain (loss)		Amount of			Location of gain (loss)	Amount of
		gain (loss)				reclassified from accumulated OCI(i) into income (effective element)		gain (loss)			recognized in income	gain (loss)
		recognized						reclassified			on derivative (ineffective hedges and ineffective element of effective hedges)	recognized
		in OCI(i)on derivative (effective element)						from				in income
								accumulated				on derivative
								OCI(i) into				(ineffective
								income(effective element)				hedges and
												ineffective
												element of effective hedges)
		(millions)						(millions)				(millions)
	Year Ended December 31, 2014
	Interest rate swaps	$	—			Investment income		$	(5	)	Other income (expense), net	$	—
	Treasury locks	—				Interest expense		(1		)	Interest expense	—
	Forward exchange contracts	(31		)		Other income (expense), net		16			Interest expense	(1		)
	Total	$	(31	)				$	10			$	(1	)
	Year Ended December 31, 2013
	Interest rate swaps	$	—			Investment income		$	(5	)	Other income (expense), net	$	—
	Treasury locks	19				Interest expense		—			Interest expense	2
	Forward exchange contracts	10				Other income (expense), net		1			Interest expense	1
	Total	$	29					$	(4	)		$	3
	Year Ended December 31, 2012
	Interest rate swaps	$	3			Investment income		$	(5	)	Other income (expense), net	$	—
	Forward exchange contracts	11				Other income (expense), net		(4		)	Interest expense	1
	Total	$	14					$	(9	)		$	1
	_________________________________
	Amounts above shown gross of tax.
	(i)	OCI means other comprehensive income.

Fair_Value_Measurement_Tables

Fair Value Measurement (Tables)	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Assets and liabilities measured at fair value on a recurring basis
		31-Dec-14
		Quoted		Significant		Significant
		prices in		other		other
		active		observable		unobservable
		markets		inputs		inputs
		for
		identical
		assets
		Level 1		Level 2		Level 3		Total
				(millions)
	Assets at fair value:
	Derivative financial instruments	—		26		—		26
	Total assets	$	—	$	26	$	—	$	26
	Liabilities at fair value:
	Derivative financial instruments	$	—	$	21	$	—	$	21
	Total liabilities	$	—	$	21	$	—	$	21
		31-Dec-13
		Quoted		Significant		Significant
		prices in		other		other
		active		observable		unobservable
		markets		inputs		inputs
		for
		identical
		assets
		Level 1		Level 2		Level 3		Total
				(millions)
	Assets at fair value:
	Derivative financial instruments	—		23		—		23
	Total assets	$	—	$	23	$	—	$	23
	Liabilities at fair value:
	Derivative financial instruments	$	—	$	2	$	—	$	2
	Total liabilities	$	—	$	2	$	—	$	2
Summary of the estimated fair value of the company's financial instruments held or issued to finance the company's operations
		December 31,
		2014				2013
		Carrying		Fair		Carrying		Fair
		amount		value		amount		value
				(millions)
	Assets:
	Cash and cash equivalents	$	635	$	635	$	796	$	796
	Fiduciary funds (included within Fiduciary assets)	$	1,888	$	1,888	$	1,662	$	1,662
	Liabilities:
	Current portion of long-term debt	$	167	$	169	$	15	$	15
	Long-term debt	2,142		2,327		2,311		2,444

Segment_Information_Tables

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Information regarding operating segments
		Commissions			Investment			Other			Total		Depreciation		Operating
		and fees			income			income			revenues		and		income (loss)
													amortization
											(millions)
	Year Ended December 31, 2014
	Global	$	1,386		$	9		$	15		$	1,410	$	36	$	352
	North America	1,365			1			4			1,370		71		273
	International	1,016			6			—			1,022		27		197
	Total segments	3,767			16			19			3,802		134		822
	Corporate and other(i)	—			—			—			—		12		(175		)
	Total consolidated	$	3,767		$	16		$	19		$	3,802	$	146	$	647
	Year Ended December 31, 2013
	Global	$	1,358		$	6		$	—		$	1,364	$	36	$	376
	North America	1,349			2			7			1,358		77		249
	International	926			7			—			933		22		178
	Total segments	3,633			15			7			3,655		135		803
	Corporate and other(i)	—			—			—			—		14		(140		)
	Total consolidated	$	3,633		$	15		$	7		$	3,655	$	149	$	663
	Year Ended December 31, 2012
	Global	$	1,303		$	7		$	—		$	1,310	$	33	$	400
	North America	1,281			3			4			1,288		76		252
	International	874			8			—			882		23		167
	Total segments	3,458			18			4			3,480		132		819
	Corporate and other(i)	—			—			—			—		6		(1,044		)
	Total consolidated	$	3,458		$	18		$	4		$	3,480	$	138	$	(225	)
	_________________________________
	(i)	See the following table for an analysis of the ‘Corporate and other’ line.
Schedule Of Segment Reporting Information By Segment Table [Text Block]
		Years ended December 31,
		2014			2013			2012
		(millions)
	Costs of the holding company	$	(13	)	$	(10	)	$	(4	)
	Costs related to Group functions, leadership and projects	(194		)	(118		)	(114		)
	Non-servicing elements of defined benefit pension	53			42			38
	Significant legal and regulatory settlements managed centrally	(2		)	(6		)	(6		)
	Restructuring costs relating to the Operational Improvement Program	(17		)	—			—
	Additional incentive accrual for change in remuneration policy	—			—			(252		)
	Write-off of unamortized cash retention awards debtor	—			—			(200		)
	Goodwill impairment charge	—			—			(492		)
	India joint venture settlement	—			—			(11		)
	Insurance recovery	—			—			10
	Write-off of uncollectible accounts receivable balance in Chicago	—			—			(13		)
	Expense Reduction Initiative	—			(46		)	—
	Fees related to the extinguishment of debt	—			(1		)	—
	Other	(2		)	(1		)	—
	Total Corporate and Other	$	(175	)	$	(140	)	$	(1,044	)
Total consolidated operating income	The following table reconciles total consolidated operating income (loss), as disclosed in the operating segment tables above, to consolidated income from continuing operations before income taxes and interest in earnings of associates.
		Years ended December 31,
		2014			2013			2012
		(millions)
	Total consolidated operating income (loss)	$	647		$	663		$	(225	)
	Other (expense) income, net	6			22			16
	Loss on extinguishment of debt	—			(60		)	—
	Interest expense	(135		)	(126		)	(128		)
	Income (loss) before income taxes and interest in earnings of associates	$	518		$	499		$	(337	)
Operating segment revenue by product
		Years ended December 31,
		2014			2013			2012			2014		2013		2012			2014		2013		2012		2014		2013		2012
		Global									North America							International						Total
		(millions)
	Commissions and fees:
	Retail insurance services	$	153		$	158		$	165		$	1,365	$	1,349	$	1,281		$	1,016	$	926	$	874	$	2,534	$	2,433	$	2,320
	Specialty insurance services	1,233			1,200			1,138			—		—		—			—		—		—		1,233		1,200		1,138
	Total commissions and fees	1,386			1,358			1,303			1,365		1,349		1,281			1,016		926		874		3,767		3,633		3,458
	Investment income	9			6			7			1		2		3			6		7		8		16		15		18
	Other income	15			—			—			4		7		4			—		—		—		19		7		4
	Total Revenues	$	1,410		$	1,364		$	1,310		$	1,370	$	1,358	$	1,288		$	1,022	$	933	$	882	$	3,802	$	3,655	$	3,480
Information regarding geographic locations
		Years Ended December 31,
		2014			2013			2012
		(millions)
	Commissions and fees(i)
	UK	$	1,027		$	1,026		$	980
	US	1,592			1,549			1,484
	Other(ii)	1,148			1,058			994
	Total	$	3,767		$	3,633		$	3,458
		December 31,
		2014			2013
		(millions)
	Fixed assets
	UK	$	232		$	233
	US	193			203
	Other(ii)	58			45
	Total	$	483		$	481
	_________________________________
	(i)	Commissions and fees are attributed to countries based upon the location of the subsidiary generating the revenue.
	(ii)	Other than in the United Kingdom and the United States, the Company does not conduct business in any country in which its commissions and fees and or fixed assets exceed 10 percent of consolidated commissions and fees and or fixed assets, respectively.

Subsidiary_Undertakings_Tables

Subsidiary Undertakings (Tables)	12 Months Ended
	Dec. 31, 2014
Investments in and Advances to Affiliates, Schedule of Investments [Abstract]
List of Group's subsidiary undertakings
	Subsidiary name	Country of registration	Class of share	Percentage ownership
	Holding companies
	TAI Limited	England and Wales	Ordinary shares	100	%
	Trinity Acquisition Limited	England and Wales	Ordinary shares	100	%
	Willis Faber Limited	England and Wales	Ordinary shares	100	%
	Willis Group Limited	England and Wales	Ordinary shares	100	%
	Willis Investment UK Holdings Limited	England and Wales	Ordinary shares	100	%
	Willis Netherlands Holdings B.V.	Netherlands	Ordinary shares	100	%
	Willis Europe B.V.	England and Wales	Ordinary shares	100	%
	Insurance broking companies
	Willis HRH, Inc.	USA	Common shares	100	%
	Willis Limited	England and Wales	Ordinary shares	100	%
	Willis North America, Inc.	USA	Common shares	100	%
	Willis Re, Inc.	USA	Common shares	100	%

Financial_Information_for_Pare2

Financial Information for Parent Guarantor, Other Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Tables)	12 Months Ended
	Dec. 31, 2014
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Income Statement [Table Text Block]	Condensed Consolidating Statement of Operations
		Year Ended December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	REVENUES
	Commissions and fees	$	—		$	—		$	8		$	3,759		$	—		$	3,767
	Investment income	—			—			—			16			—			16
	Other income	—			—			—			19			—			19
	Total revenues	—			—			8			3,794			—			3,802
	EXPENSES
	Salaries and benefits	(1		)	—			(81		)	(2,232		)	—			(2,314		)
	Other operating expenses	(16		)	(95		)	(38		)	(510		)	—			(659		)
	Depreciation expense	—			(4		)	(17		)	(71		)	—			(92		)
	Amortization of intangible assets	—			—			—			(54		)	—			(54		)
	Restructuring costs	—			(11		)	(3		)	(22		)	—			(36		)
	Total expenses	(17		)	(110		)	(139		)	(2,889		)	—			(3,155		)
	OPERATING (LOSS) INCOME	(17		)	(110		)	(131		)	905			—			647
	Other (expense) income, net	(15		)	(220		)	—			11			230			6
	Income from Group undertakings	—			221			313			102			(636		)	—
	Expenses due to Group undertakings	—			(33		)	(179		)	(424		)	636			—
	Interest expense	(43		)	(35		)	(45		)	(12		)	—			(135		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(177		)	(42		)	582			230			518
	Income taxes	—			25			24			(208		)	—			(159		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(152		)	(18		)	374			230			359
	Interest in earnings of associates, net of tax	—			10			—			4			—			14
	Equity account for subsidiaries	437			570			76			—			(1,083		)	—
	NET INCOME	362			428			58			378			(853		)	373
	Less: Net loss attributable to noncontrolling interests	—			—			—			(11		)	—			(11		)
	NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	362		$	428		$	58		$	367		$	(853	)	$	362
	Condensed Consolidating Statement of Operations
		Year Ended December 31, 2012
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	REVENUES
	Commissions and fees	$	—		$	—		$	—		$	3,458		$	—		$	3,458
	Investment income	—			—			1			17			—			18
	Other income	—			—			—			4			—			4
	Total revenues	—			—			1			3,479			—			3,480
	EXPENSES
	Salaries and benefits	(2		)	—			(96		)	(2,377		)	—			(2,475		)
	Other operating expenses	(6		)	(80		)	(78		)	(436		)	—			(600		)
	Depreciation expense	—			(1		)	(15		)	(63		)	—			(79		)
	Amortization of intangible assets	—			—			—			(59		)	—			(59		)
	Goodwill impairment charge	—			—			—			(492		)	—			(492		)
	Total expenses	(8		)	(81		)	(189		)	(3,427		)	—			(3,705		)
	OPERATING (LOSS) INCOME	(8		)	(81		)	(188		)	52			—			(225		)
	Other income (expense), net	2			(2		)	(1		)	17			—			16
	Income from Group undertakings	—			201			316			111			(628		)	—
	Expenses due to Group undertakings	—			(67		)	(147		)	(414		)	628			—
	Interest expense	(43		)	(7		)	(70		)	(8		)	—			(128		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(49		)	44			(90		)	(242		)	—			(337		)
	Income taxes	—			31			34			(166		)	—			(101		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(49		)	75			(56		)	(408		)	—			(438		)
	Interest in earnings of associates, net of tax	—			8			—			(3		)	—			5
	Equity account for subsidiaries	(397		)	(480		)	(172		)	—			1,049			—
	NET LOSS	(446		)	(397		)	(228		)	(411		)	1,049			(433		)
	Less: Net income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
	NET LOSS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	(446	)	$	(397	)	$	(228	)	$	(424	)	$	1,049		$	(446	)
	Condensed Consolidating Statement of Operations
		Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	—		$	8		$	3,625		$	—		$	3,633
Investment income	—			—			—			15			—			15
Other income	—			—			—			7			—			7
Total revenues	—			—			8			3,647			—			3,655
EXPENSES
Salaries and benefits	(1		)	—			(103		)	(2,103		)	—			(2,207		)
Other operating expenses	(5		)	(69		)	(163		)	(399		)	—			(636		)
Depreciation expense	—			(3		)	(20		)	(71		)	—			(94		)
Amortization of intangible assets	—			—			—			(55		)	—			(55		)
Total expenses	(6		)	(72		)	(286		)	(2,628		)	—			(2,992		)
OPERATING (LOSS) INCOME	(6		)	(72		)	(278		)	1,019			—			663
Other income (expense), net	5			(4		)	—			31			(10		)	22
Income from Group undertakings	—			191			364			86			(641		)	—
Expenses due to Group undertakings	(10		)	(34		)	(141		)	(456		)	641			—
Loss on extinguishment of debt	—			—			(60		)	—			—			(60		)
Interest expense	(42		)	(16		)	(63		)	(5		)	—			(126		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(53		)	65			(178		)	675			(10		)	499
Income taxes	—			23			—			(145		)	—			(122		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(53		)	88			(178		)	530			(10		)	377
Interest in earnings of associates, net of tax	—			9			—			(9		)	—			—
Equity account for subsidiaries	418			320			150			—			(888		)	—
NET INCOME (LOSS)	365			417			(28		)	521			(898		)	377
Less: Net income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
NET INCOME (LOSS) ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	365		$	417		$	(28	)	$	509		$	(898	)	$	365
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2014
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
REVENUES
Commissions and fees	$	—		$	8		$	3,759		$	—		$	3,767
Investment income	—			—			16			—			16
Other income	—			—			19			—			19
Total revenues	—			8			3,794			—			3,802
EXPENSES
Salaries and benefits	(1		)	(81		)	(2,232		)	—			(2,314		)
Other operating expenses	(16		)	(133		)	(510		)	—			(659		)
Depreciation expense	—			(21		)	(71		)	—			(92		)
Amortization of intangible assets	—			—			(54		)	—			(54		)
Restructuring expenses	—			(14		)	(22		)	—			(36		)
Total expenses	(17		)	(249		)	(2,889		)	—			(3,155		)
OPERATING (LOSS) INCOME	(17		)	(241		)	905			—			647
Other (expense) income, net	(15		)	(220		)	11			230			6
Income from Group undertakings	—			424			102			(526		)	—
Expenses due to Group undertakings	—			(102		)	(424		)	526			—
Interest expense	(43		)	(80		)	(12		)	—			(135		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(219		)	582			230			518
Income taxes	—			49			(208		)	—			(159		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(170		)	374			230			359
Interest in earnings of associates, net of tax	—			10			4			—			14
Equity account for subsidiaries	437			588			—			(1,025		)	—
NET INCOME	362			428			378			(795		)	373
Less: Net income attributable to noncontrolling interests	—			—			(11		)	—			(11		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	362		$	428		$	367		$	(795	)	$	362
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2012
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
REVENUES
Commissions and fees	$	—		$	—		$	3,458		$	—		$	3,458
Investment income	—			1			17			—			18
Other income	—			—			4			—			4
Total revenues	—			1			3,479			—			3,480
EXPENSES
Salaries and benefits	(2		)	(96		)	(2,377		)	—			(2,475		)
Other operating expenses	(6		)	(158		)	(436		)	—			(600		)
Depreciation expense	—			(16		)	(63		)	—			(79		)
Amortization of intangible assets	—			—			(59		)	—			(59		)
Goodwill impairment charge	—			—			(492		)	—			(492		)
Total expenses	(8		)	(270		)	(3,427		)	—			(3,705		)
OPERATING (LOSS) INCOME	(8		)	(269		)	52			—			(225		)
Other income (expense), net	2			(3		)	17			—			16
Income from Group undertakings	—			409			111			(520		)	—
Expenses due to Group undertakings	—			(106		)	(414		)	520			—
Interest expense	(43		)	(77		)	(8		)	—			(128		)
LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(49		)	(46		)	(242		)	—			(337		)
Income taxes	—			65			(166		)	—			(101		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(49		)	19			(408		)	—			(438		)
Interest in earnings of associates, net of tax	—			8			(3		)	—			5
Equity account for subsidiaries	(397		)	(424		)	—			821			—
NET LOSS	(446		)	(397		)	(411		)	821			(433		)
Less: Net income attributable to noncontrolling interests	—			—			(13		)	—			(13		)
NET LOSS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	(446	)	$	(397	)	$	(424	)	$	821		$	(446	)
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2013
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
REVENUES
Commissions and fees	$	—		$	8		$	3,625		$	—		$	3,633
Investment income	—			—			15			—			15
Other income	—			—			7			—			7
Total revenues	—			8			3,647			—			3,655
EXPENSES
Salaries and benefits	(1		)	(103		)	(2,103		)	—			(2,207		)
Other operating expenses	(5		)	(232		)	(399		)	—			(636		)
Depreciation expense	—			(23		)	(71		)	—			(94		)
Amortization of intangible assets	—			—			(55		)	—			(55		)
Total expenses	(6		)	(358		)	(2,628		)	—			(2,992		)
OPERATING (LOSS) INCOME	(6		)	(350		)	1,019			—			663
Other income (expense), net	5			(4		)	31			(10		)	22
Income from Group undertakings	—			466			86			(552		)	—
Expenses due to Group undertakings	(10		)	(86		)	(456		)	552			—
Loss on extinguishment of debt	—			(60		)	—			—			(60		)
Interest expense	(42		)	(79		)	(5		)	—			(126		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(113		)	675			(10		)	499
Income taxes	—			23			(145		)	—			(122		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(90		)	530			(10		)	377
Interest in earnings of associates, net of tax	—			9			(9		)	—			—
Equity account for subsidiaries	418			498			—			(916		)	—
NET INCOME	365			417			521			(926		)	377
Less: Net income attributable to noncontrolling interests	—			—			(12		)	—			(12		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	365		$	417		$	509		$	(926	)	$	365
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	—		$	—		$	3,458		$	—		$	3,458
Investment income	—			1			—			17			—			18
Other income	—			—			—			4			—			4
Total revenues	—			1			—			3,479			—			3,480
EXPENSES
Salaries and benefits	(2		)	(96		)	—			(2,377		)	—			(2,475		)
Other operating expenses	(6		)	(158		)	—			(436		)	—			(600		)
Depreciation expense	—			(16		)	—			(63		)	—			(79		)
Amortization of intangible assets	—			—			—			(59		)	—			(59		)
Goodwill impairment	—			—			—			(492		)	—			(492		)
Total expenses	(8		)	(270		)	—			(3,427		)	—			(3,705		)
OPERATING (LOSS) INCOME	(8		)	(269		)	—			52			—			(225		)
Other income (expense), net	2			(4		)	1			17			—			16
Income from Group undertakings	—			436			79			111			(626		)	—
Expenses due to Group undertakings	—			(185		)	(27		)	(414		)	626			—
Interest expense	(43		)	(69		)	(8		)	(8		)	—			(128		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(49		)	(91		)	45			(242		)	—			(337		)
Income taxes	—			76			(11		)	(166		)	—			(101		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(49		)	(15		)	34			(408		)	—			(438		)
Interest in earnings of associates, net of tax	—			8			—			(3		)	—			5
Equity account for subsidiaries	(397		)	(390		)	(461		)	—			1,248			—
NET LOSS	(446		)	(397		)	(427		)	(411		)	1,248			(433		)
Less: Net income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
NET LOSS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	(446	)	$	(397	)	$	(427	)	$	(424	)	$	1,248		$	(446	)
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	8		$	—		$	3,625		$	—		$	3,633
Investment income	—			—			—			15			—			15
Other income	—			—			—			7			—			7
Total revenues	—			8			—			3,647			—			3,655
EXPENSES
Salaries and benefits	(1		)	(103		)	—			(2,103		)	—			(2,207		)
Other operating expenses	(5		)	(231		)	(1		)	(399		)	—			(636		)
Depreciation expense	—			(23		)	—			(71		)	—			(94		)
Amortization of intangible assets	—			—			—			(55		)	—			(55		)
Total expenses	(6		)	(357		)	(1		)	(2,628		)	—			(2,992		)
OPERATING (LOSS) INCOME	(6		)	(349		)	(1		)	1,019			—			663
Other income (expense), net	5			(4		)	—			31			(10		)	22
Income from Group undertakings	—			491			68			86			(645		)	—
Expenses due to Group undertakings	(10		)	(153		)	(26		)	(456		)	645			—
Loss on extinguishment of debt	—			(60		)	—			—			—			(60		)
Interest expense	(42		)	(61		)	(18		)	(5		)	—			(126		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(136		)	23			675			(10		)	499
Income taxes	—			29			(6		)	(145		)	—			(122		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(107		)	17			530			(10		)	377
Interest in earnings of associates, net of tax	—			9			—			(9		)	—			—
Equity account for subsidiaries	418			515			344			—			(1,277		)	—
NET INCOME	365			417			361			521			(1,287		)	377
Less: Net income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	365		$	417		$	361		$	509		$	(1,287	)	$	365
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	8		$	—		$	3,759		$	—		$	3,767
Investment income	—			—			—			16			—			16
Other income	—			—			—			19			—			19
Total revenues	—			8			—			3,794			—			3,802
EXPENSES
Salaries and benefits	(1		)	(81		)	—			(2,232		)	—			(2,314		)
Other operating expenses	(16		)	(133		)	—			(510		)	—			(659		)
Depreciation expense	—			(21		)	—			(71		)	—			(92		)
Amortization of intangible assets	—			—			—			(54		)	—			(54		)
Restructuring expenses	—			(14		)	—			(22		)	—			(36		)
Total expenses	(17		)	(249		)	—			(2,889		)	—			(3,155		)
OPERATING (LOSS) INCOME	(17		)	(241		)	—			905			—			647
Other (expense) income, net	(15		)	(220		)	—			11			230			6
Income from Group undertakings	—			450			91			102			(643		)	—
Expenses due to Group undertakings	—			(190		)	(29		)	(424		)	643			—
Interest expense	(43		)	(44		)	(36		)	(12		)	—			(135		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(245		)	26			582			230			518
Income taxes	—			54			(5		)	(208		)	—			(159		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(191		)	21			374			230			359
Interest in earnings of associates, net of tax	—			10			—			4			—			14
Equity account for subsidiaries	437			609			314			—			(1,360		)	—
NET INCOME	362			428			335			378			(1,130		)	373
Less: Net income attributable to noncontrolling interests	—			—			—			(11		)	—			(11		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	362		$	428		$	335		$	367		$	(1,130	)	$	362
Condensed Statement of Comprehensive Income [Table Text Block]	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	Comprehensive (loss) income	$	(11	)	$	69		$	(110	)	$	49		$	(3	)	$	(6	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(5		)	—			(5		)
	Comprehensive (loss) income attributable to Willis Group Holdings	$	(11	)	$	69		$	(110	)	$	44		$	(3	)	$	(11	)
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2012
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	Comprehensive loss	$	(552	)	$	(494	)	$	(263	)	$	(519	)	$	1,289		$	(539	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
	Comprehensive loss attributable to Willis Group Holdings	$	(552	)	$	(494	)	$	(263	)	$	(532	)	$	1,289		$	(552	)
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2013
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	Comprehensive income	$	522		$	565		$	74		$	636		$	(1,263	)	$	534
	Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
	Comprehensive income attributable to Willis Group Holdings	$	522		$	565		$	74		$	624		$	(1,263	)	$	522
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2014
		Willis			The Guarantors			Other			Consolidating			Consolidated
		Group									adjustments
		Holdings—the Parent Issuer
		(millions)
	Comprehensive (loss) income	$	(11	)	$	69		$	49		$	(113	)	$	(6	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			(5		)	—			(5		)
	Comprehensive (loss) income attributable to Willis Group Holdings	$	(11	)	$	69		$	44		$	(113	)	$	(11	)
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2012
		Willis			The Guarantors			Other			Consolidating			Consolidated
		Group									adjustments
		Holdings—the Parent Issuer
		(millions)
	Comprehensive loss	$	(552	)	$	(494	)	$	(519	)	$	1,026		$	(539	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			(13		)	—			(13		)
	Comprehensive loss attributable to Willis Group Holdings	$	(552	)	$	(494	)	$	(532	)	$	1,026		$	(552	)
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2013
		Willis			The Guarantors			Other			Consolidating			Consolidated
		Group									adjustments
		Holdings—the Parent Issuer
		(millions)
	Comprehensive income	$	522		$	565		$	636		$	(1,189	)	$	534
	Less: Comprehensive income attributable to noncontrolling interests	—			—			(12		)	—			(12		)
	Comprehensive income attributable to Willis Group Holdings	$	522		$	565		$	624		$	(1,189	)	$	522
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2012
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	Comprehensive loss	$	(552	)	$	(494	)	$	(528	)	$	(519	)	$	1,554		$	(539	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
	Comprehensive loss attributable to Willis Group Holdings	$	(552	)	$	(494	)	$	(528	)	$	(532	)	$	1,554		$	(552	)
	Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
Comprehensive (loss) income	$	(11	)	$	69		$	(5	)	$	49		$	(108	)	$	(6	)
Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(5		)	—			(5		)
Comprehensive (loss) income attributable to Willis Group Holdings	$	(11	)	$	69		$	(5	)	$	44		$	(108	)	$	(11	)
Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
Comprehensive income	$	522		$	565		$	504		$	636		$	(1,693	)	$	534
Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
Comprehensive income attributable to Willis Group Holdings	$	522		$	565		$	504		$	624		$	(1,693	)	$	522
Condensed Balance Sheet [Table Text Block]	Condensed Consolidating Balance Sheet
		As at December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	ASSETS
	CURRENT ASSETS
	Cash and cash equivalents	$	9		$	2		$	—		$	624		$	—		$	635
	Accounts receivable, net	—			—			4			1,040			—			1,044
	Fiduciary assets	—			—			—			8,948			—			8,948
	Deferred tax assets	—			—			—			12			—			12
	Other current assets	1			27			10			205			(29		)	214
	Amounts due from Group undertakings	3,674			924			1,057			1,114			(6,769		)	—
	Total current assets	3,684			953			1,071			11,943			(6,798		)	10,853
	NON-CURRENT ASSETS
	Investments in subsidiaries	—			2,536			721			—			(3,257		)	—
	Fixed assets, net	—			20			42			421			—			483
	Goodwill	—			—			—			2,937			—			2,937
	Other intangible assets, net	—			—			—			450			—			450
	Investments in associates	—			147			—			22			—			169
	Deferred tax assets	—			—			—			9			—			9
	Pension benefits asset	—			—			—			314			—			314
	Other non-current assets	3			8			2			207			—			220
	Non-current amounts due from Group undertakings	—			518			740			—			(1,258		)	—
	Total non-current assets	3			3,229			1,505			4,360			(4,515		)	4,582
	TOTAL ASSETS	$	3,687		$	4,182		$	2,576		$	16,303		$	(11,313	)	$	15,435
	LIABILITIES AND STOCKHOLDERS’ EQUITY
	CURRENT LIABILITIES
	Fiduciary liabilities	$	—		$	—		$	—		$	8,948		$	—		$	8,948
	Deferred revenue and accrued expenses	1			4			30			584			—			619
	Income taxes payable	—			—			7			55			(29		)	33
	Short-term debt and current portion of long-term debt	—			17			149			1			—			167
	Deferred tax liabilities	—			—			—			21			—			21
	Other current liabilities	67			11			46			320			—			444
	Amounts due to Group undertakings	—			4,374			1,499			896			(6,769		)	—
	Total current liabilities	68			4,406			1,731			10,825			(6,798		)	10,232
	NON-CURRENT LIABILITIES
	Investments in subsidiaries	838			—			—			—			(838		)	—
	Long-term debt	796			765			581			—			—			2,142
	Liabilities for pension benefits	—			—			—			284			—			284
	Deferred tax liabilities	—			—			—			128			—			128
	Provisions for liabilities	—			—			—			194			—			194
	Other non-current liabilities	—			—			17			372			—			389
	Non-current amounts due to Group undertakings	—			—			518			740			(1,258		)	—
	Total non-current liabilities	1,634			765			1,116			1,718			(2,096		)	3,137
	TOTAL LIABILITIES	$	1,702		$	5,171		$	2,847		$	12,543		$	(8,894	)	$	13,369
	Condensed Consolidating Balance Sheet
		As at December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	REDEEMABLE NONCONTROLLING INTEREST	—			—			—			59			—			59
	EQUITY
	Total Willis Group Holdings stockholders’ equity	1,985			(989		)	(271		)	3,679			(2,419		)	1,985
	Noncontrolling interests	—			—			—			22			—			22
	Total equity	1,985			(989		)	(271		)	3,701			(2,419		)	2,007
	TOTAL LIABILITIES AND EQUITY	$	3,687		$	4,182		$	2,576		$	16,303		$	(11,313	)	$	15,435
	Condensed Consolidating Balance Sheet
		As at December 31, 2013
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	3		$	3		$	—		$	790		$	—		$	796
Accounts receivable, net	—			—			4			1,037			—			1,041
Fiduciary assets	—			—			—			8,412			—			8,412
Deferred tax assets	—			—			—			16			(1		)	15
Other current assets	1			21			10			186			(21		)	197
Amounts due by group undertakings	4,051			903			1,317			1,484			(7,755		)	—
Total current assets	4,055			927			1,331			11,925			(7,777		)	10,461
NON-CURRENT ASSETS
Investments in subsidiaries	—			2,838			1,021			—			(3,859		)	—
Fixed assets, net	—			15			51			415			—			481
Goodwill	—			—			—			2,838			—			2,838
Other intangible assets, net	—			—			—			353			—			353
Investments in associates	—			156			—			20			—			176
Deferred tax assets	—			—			—			7			—			7
Pension benefits asset	—			—			—			278			—			278
Other non-current assets	4			9			5			188			—			206
Non-current amounts due by group undertakings	—			518			690			—			(1,208		)	—
Total non-current assets	4			3,536			1,767			4,099			(5,067		)	4,339
TOTAL ASSETS	$	4,059		$	4,463		$	3,098		$	16,024		$	(12,844	)	$	14,800
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,412		$	—		$	8,412
Deferred revenue and accrued expenses	2			1			28			555			—			586
Income taxes payable	—			3			—			39			(21		)	21
Short-term debt and current portion of long-term debt	—			15			—			—			—			15
Deferred tax liabilities	—			—			—			25			—			25
Other current liabilities	62			15			38			300			—			415
Amounts due to group undertakings	—			4,760			1,662			1,333			(7,755		)	—
Total current liabilities	64			4,794			1,728			10,664			(7,776		)	9,474
NON-CURRENT LIABILITIES
Investments in subsidiaries	985			—			—			—			(985		)	—
Long-term debt	795			782			733			1			—			2,311
Liabilities for pension benefits	—			—			—			136			—			136
Deferred tax liabilities	—			1			—			55			—			56
Provisions for liabilities	—			—			—			206			—			206
Other non-current liabilities	—			—			48			326			—			374
Non-current amounts due to group undertakings	—			—			518			690			(1,208		)	—
Total non-current liabilities	1,780			783			1,299			1,414			(2,193		)	3,083
TOTAL LIABILITIES	$	1,844		$	5,577		$	3,027		$	12,078		$	(9,969	)	$	12,557
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
EQUITY
Total Willis Group Holdings stockholders’ equity	2,215			(1,114		)	71			3,918			(2,875		)	2,215
Noncontrolling interests	—			—			—			28			—			28
Total equity	2,215			(1,114		)	71			3,946			(2,875		)	2,243
TOTAL LIABILITIES AND EQUITY	$	4,059		$	4,463		$	3,098		$	16,024		$	(12,844	)	$	14,800
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	9		$	2		$	624		$	—		$	635
Accounts receivable, net	—			4			1,040			—			1,044
Fiduciary assets	—			—			8,948			—			8,948
Deferred tax assets	—			—			12			—			12
Other current assets	1			37			205			(29		)	214
Amounts due from group undertakings	3,674			731			1,114			(5,519		)	—
Total current assets	3,684			774			11,943			(5,548		)	10,853
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,528			—			(3,528		)	—
Fixed assets, net	—			62			421			—			483
Goodwill	—			—			2,937			—			2,937
Other intangible assets, net	—			—			450			—			450
Investments in associates	—			147			22			—			169
Deferred tax assets	—			—			9			—			9
Pension benefits asset	—			—			314			—			314
Other non-current assets	3			10			207			—			220
Non-current amounts due from group undertakings	—			740			—			(740		)	—
Total non-current assets	3			4,487			4,360			(4,268		)	4,582
TOTAL ASSETS	$	3,687		$	5,261		$	16,303		$	(9,816	)	$	15,435
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	8,948		$	—		$	8,948
Deferred revenue and accrued expenses	1			34			584			—			619
Income taxes payable	—			7			55			(29		)	33
Short-term debt and current portion on long-term debt	—			166			1			—			167
Deferred tax liabilities	—			—			21			—			21
Other current liabilities	67			57			320			—			444
Amounts due to group undertakings	—			4,623			896			(5,519		)	—
Total current liabilities	68			4,887			10,825			(5,548		)	10,232
NON-CURRENT LIABILITIES
Investments in subsidiaries	838			—			—			(838		)	—
Long-term debt	796			1,346			—			—			2,142
Liabilities for pension benefits	—			—			284			—			284
Deferred tax liabilities	—			—			128			—			128
Provisions for liabilities	—			—			194			—			194
Other non-current liabilities	—			17			372			—			389
Non-current amounts due to group undertakings	—			—			740			(740		)	—
Total non-current liabilities	1,634			1,363			1,718			(1,578		)	3,137
TOTAL LIABILITIES	$	1,702		$	6,250		$	12,543		$	(7,126	)	$	13,369
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
REDEEMABLE NONCONTROLLING INTEREST	—			—			59			—			59
EQUITY
Total Willis Group Holdings stockholders’ equity	1,985			(989		)	3,679			(2,690		)	1,985
Noncontrolling interests	—			—			22			—			22
Total equity	1,985			(989		)	3,701			(2,690		)	2,007
TOTAL LIABILITIES AND EQUITY	$	3,687		$	5,261		$	16,303		$	(9,816	)	$	15,435
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	3		$	3		$	790		$	—		$	796
Accounts receivable, net	—			4			1,037			—			1,041
Fiduciary assets	—			—			8,412			—			8,412
Deferred tax assets	—			—			16			(1		)	15
Other current assets	1			31			186			(21		)	197
Amounts due from group undertakings	4,051			975			1,484			(6,510		)	—
Total current assets	4,055			1,013			11,925			(6,532		)	10,461
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,788			—			(3,788		)	—
Fixed assets, net	—			66			415			—			481
Goodwill	—			—			2,838			—			2,838
Other intangible assets, net	—			—			353			—			353
Investments in associates	—			156			20			—			176
Deferred tax assets	—			—			7			—			7
Pension benefits asset	—			—			278			—			278
Other non-current assets	4			14			188			—			206
Non-current amounts due from group undertakings	—			690			—			(690		)	—
Total non-current assets	4			4,714			4,099			(4,478		)	4,339
TOTAL ASSETS	$	4,059		$	5,727		$	16,024		$	(11,010	)	$	14,800
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	8,412		$	—		$	8,412
Deferred revenue and accrued expenses	2			29			555			—			586
Income taxes payable	—			3			39			(21		)	21
Short-term debt and current portion of long-term debt	—			15			—			—			15
Deferred tax liabilities	—			—			25			—			25
Other current liabilities	62			53			300			—			415
Amounts due to group undertakings	—			5,177			1,333			(6,510		)	—
Total current liabilities	64			5,277			10,664			(6,531		)	9,474
NON-CURRENT LIABILITIES
Investments in subsidiaries	985			—			—			(985		)	—
Long-term debt	795			1,515			1			—			2,311
Liabilities for pension benefits	—			—			136			—			136
Deferred tax liabilities	—			1			55			—			56
Provisions for liabilities	—			—			206			—			206
Other non-current liabilities	—			48			326			—			374
Non-current amounts due to group undertakings	—			—			690			(690		)	—
Total non-current liabilities	1,780			1,564			1,414			(1,675		)	3,083
TOTAL LIABILITIES	$	1,844		$	6,841		$	12,078		$	(8,206	)	$	12,557
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
EQUITY
Total Willis Group Holdings stockholders’ equity	2,215			(1,114		)	3,918			(2,804		)	2,215
Noncontrolling interests	—			—			28			—			28
Total equity	2,215			(1,114		)	3,946			(2,804		)	2,243
TOTAL LIABILITIES AND EQUITY	$	4,059		$	5,727		$	16,024		$	(11,010	)	$	14,800
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	9		$	2		$	—		$	624		$	—		$	635
Accounts receivable, net	—			4			—			1,040			—			1,044
Fiduciary assets	—			—			—			8,948			—			8,948
Deferred tax assets	—			—			—			12			—			12
Other current assets	1			41			1			205			(34		)	214
Amounts due from group undertakings	3,674			1,154			797			1,114			(6,739		)	—
Total current assets	3,684			1,201			798			11,943			(6,773		)	10,853
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,478			2,578			—			(6,056		)	—
Fixed assets, net	—			62			—			421			—			483
Goodwill	—			—			—			2,937			—			2,937
Other intangible assets, net	—			—			—			450			—			450
Investments in associates	—			147			—			22			—			169
Deferred tax assets	—			—			—			9			—			9
Pension benefits asset	—			—			—			314			—			314
Other non-current assets	3			2			8			207			—			220
Non-current amounts due from group undertakings	—			740			518			—			(1,258		)	—
Total non-current assets	3			4,429			3,104			4,360			(7,314		)	4,582
TOTAL ASSETS	$	3,687		$	5,630		$	3,902		$	16,303		$	(14,087	)	$	15,435
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,948		$	—		$	8,948
Deferred revenue and accrued expenses	1			34			—			584			—			619
Income taxes payable	—			7			5			55			(34		)	33
Short-term debt and current portion of long-term debt	—			149			17			1			—			167
Deferred tax liabilities	—			—			—			21			—			21
Other current liabilities	67			46			11			320			—			444
Amounts due to group undertakings	—			5,267			576			896			(6,739		)	—
Total current liabilities	68			5,503			609			10,825			(6,773		)	10,232
NON-CURRENT LIABILITIES
Investments in subsidiaries	838			—			—			—			(838		)	—
Long-term debt	796			581			765			—			—			2,142
Liabilities for pension benefits	—			—			—			284			—			284
Deferred tax liabilities	—			—			—			128			—			128
Provisions for liabilities	—			—			—			194			—			194
Other non-current liabilities	—			17			—			372			—			389
Non-current amounts due to group undertakings	—			518			—			740			(1,258		)	—
Total non-current liabilities	1,634			1,116			765			1,718			(2,096		)	3,137
TOTAL LIABILITIES	$	1,702		$	6,619		$	1,374		$	12,543		$	(8,869	)	$	13,369
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REDEEMABLE NONCONTROLLING INTEREST	—			—			—			59			—			59
EQUITY
Total Willis Group Holdings stockholders’ equity	1,985			(989		)	2,528			3,679			(5,218		)	1,985
Noncontrolling interests	—			—			—			22			—			22
Total equity	1,985			(989		)	2,528			3,701			(5,218		)	2,007
TOTAL LIABILITIES AND EQUITY	$	3,687		$	5,630		$	3,902		$	16,303		$	(14,087	)	$	15,435
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	3		$	3		$	—		$	790		$	—		$	796
Accounts receivable, net	—			4			—			1,037			—			1,041
Fiduciary assets	—			—			—			8,412			—			8,412
Deferred tax assets	—			—			—			16			(1		)	15
Other current assets	1			36			1			186			(27		)	197
Amounts due from group undertakings	4,051			975			793			1,484			(7,303		)	—
Total current assets	4,055			1,018			794			11,925			(7,331		)	10,461
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,716			2,705			—			(6,421		)	—
Fixed assets, net	—			66			—			415			—			481
Goodwill	—			—			—			2,838			—			2,838
Other intangible assets, net	—			—			—			353			—			353
Investments in associates	—			156			—			20			—			176
Deferred tax assets	—			—			—			7			—			7
Pension benefits asset	—			—			—			278			—			278
Other non-current assets	4			5			9			188			—			206
Non-current amounts due from group undertakings	—			1,113			518			—			(1,631		)	—
Total non-current assets	4			5,056			3,232			4,099			(8,052		)	4,339
TOTAL ASSETS	$	4,059		$	6,074		$	4,026		$	16,024		$	(15,383	)	$	14,800
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,412		$	—		$	8,412
Deferred revenue and accrued expenses	2			29			—			555			—			586
Income taxes payable	—			4			5			39			(27		)	21
Short-term debt and current portion of long-term debt	—			—			15			—			—			15
Deferred tax liabilities	—			—			—			25			—			25
Other current liabilities	62			42			11			300			—			415
Amounts due to group undertakings	—			5,813			157			1,333			(7,303		)	—
Total current liabilities	64			5,888			188			10,664			(7,330		)	9,474
NON-CURRENT LIABILITIES
Investments in subsidiaries	985			—			—			—			(985		)	—
Long-term debt	795			733			782			1			—			2,311
Liabilities for pension benefits	—			—			—			136			—			136
Deferred tax liabilities	—			1			—			55			—			56
Provisions for liabilities	—			—			—			206			—			206
Other non-current liabilities	—			48			—			326			—			374
Non-current amounts due to group undertakings	—			518			423			690			(1,631		)	—
Total non-current liabilities	1,780			1,300			1,205			1,414			(2,616		)	3,083
TOTAL LIABILITIES	$	1,844		$	7,188		$	1,393		$	12,078		$	(9,946	)	$	12,557
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
EQUITY
Total Willis Group Holdings stockholders’ equity	2,215			(1,114		)	2,633			3,918			(5,437		)	2,215
Noncontrolling interests	—			—			—			28			—			28
Total equity	2,215			(1,114		)	2,633			3,946			(5,437		)	2,243
TOTAL LIABILITIES AND EQUITY	$	4,059		$	6,074		$	4,026		$	16,024		$	(15,383	)	$	14,800
Condensed Cash Flow Statement [Table Text Block]	Condensed Consolidating Statement of Cash Flows
		Year Ended December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(35	)	$	387		$	265		$	212		$	(352	)	$	477
	CASH FLOWS FROM INVESTING ACTIVITIES
	Proceeds on disposal of fixed and intangible assets	—			—			1			6			(1		)	6
	Additions to fixed assets	—			(9		)	(10		)	(95		)	1			(113		)
	Additions to intangibles assets	—			—			—			(4		)	—			(4		)
	Acquisitions of subsidiaries, net of cash acquired	—			—			—			(241		)	—			(241		)
	Payments to acquire other investments	—			—			—			(10		)	—			(10		)
	Proceeds from sale of operations, net of cash disposed	—			—			—			86			—			86
	Proceeds from intercompany investing activities	361			—			120			435			(916		)	—
	Repayments of intercompany investing activities	—			(53		)	(131		)	(46		)	230			—
	Additional investment in subsidiaries	(31		)	—			—			—			31			—
	Net cash provided by (used in) investing activities	330			(62		)	(20		)	131			(655		)	(276		)
	CASH FLOWS FROM FINANCING ACTIVITIES
	Debt issuance costs	—			—			—			(3		)	—			(3		)
	Repayments of debt	—			(15		)	—			—			—			(15		)
	Repurchase of shares	(213		)	—			—			—			—			(213		)
	Proceeds from issue of shares	134			—			—			31			(31		)	134
	Excess tax benefits from share-based payment arrangements	—			—			—			5			—			5
	Dividends paid	(210		)	—			—			(352		)	352			(210		)
	Acquisition of noncontrolling interests	—			(4		)	—			—			—			(4		)
	Dividends paid to noncontrolling interests	—			—			—			(17		)	—			(17		)
	Proceeds from intercompany financing activities	—			46			4			180			(230		)	—
	Repayments of intercompany financing activities	—			(353		)	(249		)	(314		)	916			—
	Net cash used in financing activities	(289		)	(326		)	(245		)	(470		)	1,007			(323		)
	INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	6			(1		)	—			(127		)	—			(122		)
	Effect of exchange rate changes on cash and cash equivalents	—			—			—			(39		)	—			(39		)
	CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3			3			—			790			—			796
	CASH AND CASH EQUIVALENTS, END OF YEAR	$	9		$	2		$	—		$	624		$	—		$	635
	Condensed Consolidating Statement of Cash Flows
		Year Ended December 31, 2013
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	NET CASH PROVIDED BY OPERATING ACTIVITIES	$	4		$	125		$	7		$	662		$	(237	)	$	561
	CASH FLOWS FROM INVESTING ACTIVITIES
	Proceeds on disposal of fixed and intangible assets	—			—			3			9			—			12
	Additions to fixed assets	—			(7		)	(11		)	(94		)	—			(112		)
	Additions to intangible assets	—			—			—			(7		)	—			(7		)
	Acquisitions of subsidiaries, net of cash acquired	—			(237		)	(230		)	(30		)	467			(30		)
	Payments to acquire other investments	—			—			—			(7		)	—			(7		)
	Proceeds from sale of associates	—			—			—			4			—			4
	Proceeds from sale of operations, net of cash disposed	—			—			230			257			(467		)	20
	Proceeds from intercompany investing activities	383			211			36			60			(690		)	—
	Repayments of intercompany investing activities	(347		)	(442		)	(120		)	(780		)	1,689			—
	Net cash provided by (used in) investing activities	36			(475		)	(92		)	(588		)	999			(120		)
	CASH FLOWS FROM FINANCING ACTIVITIES
	Senior notes issued	—			522			—			—			—			522
	Debt issuance costs	—			(8		)	—			—			—			(8		)
	Repayments of debt	—			(15		)	(521		)	—			—			(536		)
	Tender premium on extinguishment of senior notes	—			—			(65		)	—			—			(65		)
	Proceeds from issue of shares	155			—			—			—			—			155
	Excess tax benefits from share-based payment arrangements	—			—			—			2			—			2
	Dividends paid	(193		)	—			(230		)	(7		)	237			(193		)
	Acquisition of noncontrolling interests	—			—			—			(4		)	—			(4		)
	Dividends paid to noncontrolling interests	—			—			—			(10		)	—			(10		)
	Proceeds from intercompany financing activities	—			321			901			467			(1,689		)	—
	Repayments of intercompany financing activities	—			(467		)	—			(223		)	690			—
Net cash (used in) provided by financing activities	(38		)	353			85			225			(762		)	(137		)
INCREASE IN CASH AND CASH EQUIVALENTS	2			3			—			299			—			304
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(8		)	—			(8		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	1			—			—			499			—			500
CASH AND CASH EQUIVALENTS, END OF YEAR	$	3		$	3		$	—		$	790		$	—		$	796
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(23	)	$	1,504		$	(44	)	$	(97	)	$	(815	)	$	525
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			—			5			—			5
Additions to fixed assets	—			(7		)	(19		)	(109		)	—			(135		)
Additions to intangible assets	—			—			—			(2		)	—			(2		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(33		)	—			(33		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from intercompany investing activities	256			216			44			1,230			(1,746		)	—
Repayments of intercompany investing activities	—			(318		)	(10		)	(81		)	409			—
Net cash provided by (used in) investing activities	256			(109		)	15			1,003			(1,337		)	(172		)
CASH FLOWS FROM FINANCING ACTIVITIES
Repayments of debt	—			(15		)	—			—			—			(15		)
Proceeds from issue of other debt	—			1			—			—			—			1
Repurchase of shares	(100		)	—			—			—			—			(100		)
Proceeds from issue of shares	53			—			—			—			—			53
Excess tax benefits from share-based payment arrangements	—			—			—			2			—			2
Dividends paid	(185		)	—			—			(815		)	815			(185		)
Proceeds from sale of noncontrolling interest	—			—			—			3			—			3
Acquisition of noncontrolling interests	—			—			—			(39		)	—			(39		)
Dividends paid to noncontrolling interests	—			—			—			(11		)	—			(11		)
Cash received on intercompany financing activities	—			81			—			328			(409		)	—
Cash paid on intercompany financing activities	—			(1,462		)	(134		)	(150		)	1,746			—
Net cash used in financing activities	(232		)	(1,395		)	(134		)	(682		)	2,152			(291		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1			—			(163		)	224			—			62
Effect of exchange rate changes on cash and cash equivalents	—			—			—			2			—			2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	—			—			163			273			—			436
CASH AND CASH EQUIVALENTS, END OF YEAR	$	1		$	—		$	—		$	499		$	—		$	500
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2014
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(35	)	$	652		$	212		$	(352	)	$	477
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			1			6			(1		)	6
Additions to fixed assets	—			(19		)	(95		)	1			(113		)
Additions to intangibles assets	—			—			(4		)	—			(4		)
Acquisitions of subsidiaries, net of cash acquired	—			—			(241		)	—			(241		)
Payments to acquire other investments	—			—			(10		)	—			(10		)
Proceeds from disposal of operations, net of cash disposed	—			—			86			—			86
Proceeds from intercompany investing activities	361			120			435			(916		)	—
Repayments of intercompany investing activities	—			(180		)	(46		)	226			—
Additional investment in subsidiaries	(31		)	—			—			31			—
Net cash provided by (used in) investing activities	330			(78		)	131			(659		)	(276		)
CASH FLOWS FROM FINANCING ACTIVITIES
Debt issuance costs	—			—			(3		)	—			(3		)
Repayments of debt	—			(15		)	—			—			(15		)
Repurchase of shares	(213		)	—			—			—			(213		)
Proceeds from the issue of shares	134			—			31			(31		)	134
Excess tax benefits from share-based payment arrangements	—			—			5			—			5
Dividends paid	(210		)	—			(352		)	352			(210		)
Acquisition of noncontrolling interests	—			(4		)	—			—			(4		)
Dividends paid to noncontrolling interests	—			—			(17		)	—			(17		)
Proceeds from intercompany financing activities	—			46			180			(226		)	—
Repayments of intercompany financing activities	—			(602		)	(314		)	916			—
Net cash used in financing activities	(289		)	(575		)	(470		)	1,011			(323		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	6			(1		)	(127		)	—			(122		)
Effect of exchange rate changes on cash and cash equivalents	—			—			(39		)	—			(39		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3			3			790			—			796
CASH AND CASH EQUIVALENTS, END OF YEAR	$	9		$	2		$	624		$	—		$	635
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2013
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES	$	4		$	(98	)	$	662		$	(7	)	$	561
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			3			9			—			12
Additions to fixed assets	—			(18		)	(94		)	—			(112		)
Additions to intangible assets	—			—			(7		)	—			(7		)
Acquisitions of subsidiaries, net of cash acquired	—			(237		)	(30		)	237			(30		)
Payments to acquire other investments	—			—			(7		)	—			(7		)
Proceeds from sale of associates	—			—			4			—			4
Proceeds from sale of operations, net of cash disposed	—			—			257			(237		)	20
Proceeds from intercompany investing activities	383			223			60			(666		)	—
Repayments of intercompany investing activities	(347		)	(120		)	(780		)	1,247			—
Net cash provided by (used in) investing activities	36			(149		)	(588		)	581			(120		)
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued	—			522			—			—			522
Debt issuance costs	—			(8		)	—			—			(8		)
Repayments of debt	—			(536		)	—			—			(536		)
Tender premium on extinguishment of senior notes	—			(65		)	—			—			(65		)
Proceeds from the issue of shares	155			—			—			—			155
Excess tax benefits from share-based payment arrangements	—			—			2			—			2
Dividends paid	(193		)	—			(7		)	7			(193		)
Acquisition of noncontrolling interests	—			—			(4		)	—			(4		)
Dividends paid to noncontrolling interests	—			—			(10		)	—			(10		)
Proceeds from intercompany financing activities	—			780			467			(1,247		)	—
Repayments of intercompany financing activities	—			(443		)	(223		)	666			—
Net cash (used in) provided by financing activities	(38		)	250			225			(574		)	(137		)
INCREASE IN CASH AND CASH EQUIVALENTS	2			3			299			—			304
Effect of exchange rate changes on cash and cash equivalents	—			—			(8		)	—			(8		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	1			—			499			—			500
CASH AND CASH EQUIVALENTS, END OF YEAR	$	3		$	3		$	790		$	—		$	796
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2012
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
NET CASH (USED IN) PROVIDED BY OPERATING	$	(23	)	$	1,460		$	(97	)	$	(815	)	$	525
ACTIVITIES
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			5			—			5
Additions to fixed assets	—			(26		)	(109		)	—			(135		)
Additions to intangible assets	—			—			(2		)	—			(2		)
Acquisitions of subsidiaries, net of cash acquired	—			—			(33		)	—			(33		)
Payments to acquire other investments	—			—			(7		)	—			(7		)
Proceeds from intercompany investing activities	256			150			1,230			(1,636		)	—
Repayments of intercompany investing activities	—			(328		)	(81		)	409			—
Net cash provided by (used in) investing activities	256			(204		)	1,003			(1,227		)	(172		)
CASH FLOWS FROM FINANCING ACTIVITIES
Repayments of debt	—			(15		)	—			—			(15		)
Proceeds from the issue of other debt	—			1			—			—			1
Repurchase of shares	(100		)	—			—			—			(100		)
Proceeds from issue of shares	53			—			—			—			53
Excess tax benefits from share-based payment arrangements	—			—			2			—			2
Dividends paid	(185		)	—			(815		)	815			(185		)
Proceeds from sale of noncontrolling interest	—			—			3			—			3
Acquisition of noncontrolling interests	—			—			(39		)	—			(39		)
Dividends paid to noncontrolling interests	—			—			(11		)	—			(11		)
Proceeds from intercompany financing activities	—			81			328			(409		)	—
Repayments of intercompany financing activities	—			(1,486		)	(150		)	1,636			—
Net cash used in financing activities	(232		)	(1,419		)	(682		)	2,042			(291		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1			(163		)	224			—			62
Effect of exchange rate changes on cash and cash equivalents	—			—			2			—			2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	—			163			273			—			436
CASH AND CASH EQUIVALENTS, END OF YEAR	$	1		$	—		$	499		$	—		$	500
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(35	)	$	781		$	181		$	212		$	(662	)	$	477
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			1			—			6			(1		)	6
Additions to fixed assets	—			(19		)	—			(95		)	1			(113		)
Additions to intangible assets	—			—			—			(4		)	—			(4		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(241		)	—			(241		)
Payments to acquire other investments	—			—			—			(10		)	—			(10		)
Proceeds from sale of operations, net of cash disposed	—			—			—			86			—			86
Proceeds from intercompany investing activities	361			120			—			435			(916		)	—
Repayments of intercompany investing activities	—			(180		)	(4		)	(46		)	230			—
Additional investment in subsidiaries	(31		)	—			—			—			31			—
Net cash provided by (used in) investing activities	330			(78		)	(4		)	131			(655		)	(276		)
CASH FLOWS FROM FINANCING ACTIVITIES
Debt issuance costs	—			—			—			(3		)	—			(3		)
Repayments of debt	—			—			(15		)	—			—			(15		)
Repurchase of shares	(213		)	—			—			—			—			(213		)
Proceeds from issue of shares	134			—			—			31			(31		)	134
Excess tax benefits from share-based payment arrangement	—			—			—			5			—			5
Dividends paid	(210		)	(155		)	(155		)	(352		)	662			(210		)
Acquisition of noncontrolling interests	—			(4		)	—			—			—			(4		)
Dividends paid to noncontrolling interests	—			—			—			(17		)	—			(17		)
Proceeds from intercompany financing activities	—			50			—			180			(230		)	—
Repayments of intercompany financing activities	—			(595		)	(7		)	(314		)	916			—
Net cash used in financing activities	(289		)	(704		)	(177		)	(470		)	1,317			(323		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	6			(1		)	—			(127		)	—			(122		)
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(39		)	—			(39		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3			3			—			790			—			796
CASH AND CASH EQUIVALENTS, END OF YEAR	$	9		$	2		$	—		$	624		$	—		$	635
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH PROVIDED BY OPERATING ACTIVITIES	$	4		$	399		$	63		$	662		$	(567	)	$	561
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			3			—			9			—			12
Additions to fixed assets	—			(18		)	—			(94		)	—			(112		)
Additions to intangible assets	—			—			—			(7		)	—			(7		)
Acquisitions of subsidiaries, net of cash acquired	—			(237		)	—			(30		)	237			(30		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from sale of associates	—			—			—			4			—			4
Proceeds from sale of operations, net of cash disposed	—			—			—			257			(237		)	20
Proceeds from intercompany investing activities	383			160			132			60			(735		)	—
Repayments of intercompany investing activities	(347		)	(120		)	(442		)	(780		)	1,689			—
Net cash provided by (used in) investing activities	36			(212		)	(310		)	(588		)	954			(120		)
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued	—			—			522			—			—			522
Debt issuance costs	—			—			(8		)	—			—			(8		)
Repayments of debt	—			(521		)	(15		)	—			—			(536		)
Tender premium on extinguishment of senior notes	—			(65		)	—			—			—			(65		)
Proceeds from issue of shares	155			—			—			—			—			155
Excess tax benefits from share-based payment arrangement	—			—			—			2			—			2
Dividends paid	(193		)	(230		)	(330		)	(7		)	567			(193		)
Acquisition of noncontrolling interests	—			—			—			(4		)	—			(4		)
Dividends paid to noncontrolling interests	—			—			—			(10		)	—			(10		)
Proceeds from intercompany financing activities	—			1,075			147			467			(1,689		)	—
Repayments of intercompany financing activities	—			(443		)	(69		)	(223		)	735			—
Net cash (used in) provided by financing activities	(38		)	(184		)	247			225			(387		)	(137		)
INCREASE IN CASH AND CASH EQUIVALENTS	2			3			—			299			—			304
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(8		)	—			(8		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	1			—			—			499			—			500
CASH AND CASH EQUIVALENTS, END OF YEAR	$	3		$	3		$	—		$	790		$	—		$	796
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(23	)	$	2,393		$	1,356		$	(97	)	$	(3,104	)	$	525
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			—			5			—			5
Additions to fixed assets	—			(26		)	—			(109		)	—			(135		)
Additions to intangible assets	—			—			—			(2		)	—			(2		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(33		)	—			(33		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from intercompany investing activities	256			176			78			1,230			(1,740		)	—
Repayments of intercompany investing activities	—			(197		)	(131		)	(81		)	409			—
Net cash provided by (used in) investing activities	256			(47		)	(53		)	1,003			(1,331		)	(172		)
CASH FLOWS FROM FINANCING ACTIVITIES
Repayments of debt	—			(4		)	(11		)	—			—			(15		)
Proceeds from issue of other debt	—			—			1			—			—			1
Repurchase of shares	(100		)	—			—			—			—			(100		)
Proceeds from issue of shares	53			—			—			—			—			53
Excess tax benefits from share-based payment arrangements	—			—			—			2			—			2
Dividends paid	(185		)	(1,220		)	(1,069		)	(815		)	3,104			(185		)
Proceeds from sale of noncontrolling interests	—			—			—			3			—			3
Acquisition of noncontrolling interests	—			—			—			(39		)	—			(39		)
Dividends paid to noncontrolling interests	—			—			—			(11		)	—			(11		)
Proceeds from intercompany financing activities	—			81			—			328			(409		)	—
Repayments of intercompany financing activities	—			(1,366		)	(224		)	(150		)	1,740			—
Net cash used in financing activities	(232		)	(2,509		)	(1,303		)	(682		)	4,435			(291		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1			(163		)	—			224			—			62
Effect of exchange rate changes on cash and cash equivalents	—			—			—			2			—			2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	—			163			—			273			—			436
CASH AND CASH EQUIVALENTS, END OF YEAR	$	1		$	—		$	—		$	499		$	—		$	500

Financial_Information_for_Pare3

Financial Information for Parent Issuer, Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Tables)	12 Months Ended
	Dec. 31, 2014
Financial Information for Parent Issuer Guarantor Subsidiaries and Non-Guarantor Subsidiaries Disclosure [Abstract]
Condensed Income Statement [Table Text Block]	Condensed Consolidating Statement of Operations
		Year Ended December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	REVENUES
	Commissions and fees	$	—		$	—		$	8		$	3,759		$	—		$	3,767
	Investment income	—			—			—			16			—			16
	Other income	—			—			—			19			—			19
	Total revenues	—			—			8			3,794			—			3,802
	EXPENSES
	Salaries and benefits	(1		)	—			(81		)	(2,232		)	—			(2,314		)
	Other operating expenses	(16		)	(95		)	(38		)	(510		)	—			(659		)
	Depreciation expense	—			(4		)	(17		)	(71		)	—			(92		)
	Amortization of intangible assets	—			—			—			(54		)	—			(54		)
	Restructuring costs	—			(11		)	(3		)	(22		)	—			(36		)
	Total expenses	(17		)	(110		)	(139		)	(2,889		)	—			(3,155		)
	OPERATING (LOSS) INCOME	(17		)	(110		)	(131		)	905			—			647
	Other (expense) income, net	(15		)	(220		)	—			11			230			6
	Income from Group undertakings	—			221			313			102			(636		)	—
	Expenses due to Group undertakings	—			(33		)	(179		)	(424		)	636			—
	Interest expense	(43		)	(35		)	(45		)	(12		)	—			(135		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(177		)	(42		)	582			230			518
	Income taxes	—			25			24			(208		)	—			(159		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(152		)	(18		)	374			230			359
	Interest in earnings of associates, net of tax	—			10			—			4			—			14
	Equity account for subsidiaries	437			570			76			—			(1,083		)	—
	NET INCOME	362			428			58			378			(853		)	373
	Less: Net loss attributable to noncontrolling interests	—			—			—			(11		)	—			(11		)
	NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	362		$	428		$	58		$	367		$	(853	)	$	362
	Condensed Consolidating Statement of Operations
		Year Ended December 31, 2012
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	REVENUES
	Commissions and fees	$	—		$	—		$	—		$	3,458		$	—		$	3,458
	Investment income	—			—			1			17			—			18
	Other income	—			—			—			4			—			4
	Total revenues	—			—			1			3,479			—			3,480
	EXPENSES
	Salaries and benefits	(2		)	—			(96		)	(2,377		)	—			(2,475		)
	Other operating expenses	(6		)	(80		)	(78		)	(436		)	—			(600		)
	Depreciation expense	—			(1		)	(15		)	(63		)	—			(79		)
	Amortization of intangible assets	—			—			—			(59		)	—			(59		)
	Goodwill impairment charge	—			—			—			(492		)	—			(492		)
	Total expenses	(8		)	(81		)	(189		)	(3,427		)	—			(3,705		)
	OPERATING (LOSS) INCOME	(8		)	(81		)	(188		)	52			—			(225		)
	Other income (expense), net	2			(2		)	(1		)	17			—			16
	Income from Group undertakings	—			201			316			111			(628		)	—
	Expenses due to Group undertakings	—			(67		)	(147		)	(414		)	628			—
	Interest expense	(43		)	(7		)	(70		)	(8		)	—			(128		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(49		)	44			(90		)	(242		)	—			(337		)
	Income taxes	—			31			34			(166		)	—			(101		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(49		)	75			(56		)	(408		)	—			(438		)
	Interest in earnings of associates, net of tax	—			8			—			(3		)	—			5
	Equity account for subsidiaries	(397		)	(480		)	(172		)	—			1,049			—
	NET LOSS	(446		)	(397		)	(228		)	(411		)	1,049			(433		)
	Less: Net income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
	NET LOSS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	(446	)	$	(397	)	$	(228	)	$	(424	)	$	1,049		$	(446	)
	Condensed Consolidating Statement of Operations
		Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	—		$	8		$	3,625		$	—		$	3,633
Investment income	—			—			—			15			—			15
Other income	—			—			—			7			—			7
Total revenues	—			—			8			3,647			—			3,655
EXPENSES
Salaries and benefits	(1		)	—			(103		)	(2,103		)	—			(2,207		)
Other operating expenses	(5		)	(69		)	(163		)	(399		)	—			(636		)
Depreciation expense	—			(3		)	(20		)	(71		)	—			(94		)
Amortization of intangible assets	—			—			—			(55		)	—			(55		)
Total expenses	(6		)	(72		)	(286		)	(2,628		)	—			(2,992		)
OPERATING (LOSS) INCOME	(6		)	(72		)	(278		)	1,019			—			663
Other income (expense), net	5			(4		)	—			31			(10		)	22
Income from Group undertakings	—			191			364			86			(641		)	—
Expenses due to Group undertakings	(10		)	(34		)	(141		)	(456		)	641			—
Loss on extinguishment of debt	—			—			(60		)	—			—			(60		)
Interest expense	(42		)	(16		)	(63		)	(5		)	—			(126		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(53		)	65			(178		)	675			(10		)	499
Income taxes	—			23			—			(145		)	—			(122		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(53		)	88			(178		)	530			(10		)	377
Interest in earnings of associates, net of tax	—			9			—			(9		)	—			—
Equity account for subsidiaries	418			320			150			—			(888		)	—
NET INCOME (LOSS)	365			417			(28		)	521			(898		)	377
Less: Net income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
NET INCOME (LOSS) ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	365		$	417		$	(28	)	$	509		$	(898	)	$	365
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2014
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
REVENUES
Commissions and fees	$	—		$	8		$	3,759		$	—		$	3,767
Investment income	—			—			16			—			16
Other income	—			—			19			—			19
Total revenues	—			8			3,794			—			3,802
EXPENSES
Salaries and benefits	(1		)	(81		)	(2,232		)	—			(2,314		)
Other operating expenses	(16		)	(133		)	(510		)	—			(659		)
Depreciation expense	—			(21		)	(71		)	—			(92		)
Amortization of intangible assets	—			—			(54		)	—			(54		)
Restructuring expenses	—			(14		)	(22		)	—			(36		)
Total expenses	(17		)	(249		)	(2,889		)	—			(3,155		)
OPERATING (LOSS) INCOME	(17		)	(241		)	905			—			647
Other (expense) income, net	(15		)	(220		)	11			230			6
Income from Group undertakings	—			424			102			(526		)	—
Expenses due to Group undertakings	—			(102		)	(424		)	526			—
Interest expense	(43		)	(80		)	(12		)	—			(135		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(219		)	582			230			518
Income taxes	—			49			(208		)	—			(159		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(170		)	374			230			359
Interest in earnings of associates, net of tax	—			10			4			—			14
Equity account for subsidiaries	437			588			—			(1,025		)	—
NET INCOME	362			428			378			(795		)	373
Less: Net income attributable to noncontrolling interests	—			—			(11		)	—			(11		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	362		$	428		$	367		$	(795	)	$	362
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2012
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
REVENUES
Commissions and fees	$	—		$	—		$	3,458		$	—		$	3,458
Investment income	—			1			17			—			18
Other income	—			—			4			—			4
Total revenues	—			1			3,479			—			3,480
EXPENSES
Salaries and benefits	(2		)	(96		)	(2,377		)	—			(2,475		)
Other operating expenses	(6		)	(158		)	(436		)	—			(600		)
Depreciation expense	—			(16		)	(63		)	—			(79		)
Amortization of intangible assets	—			—			(59		)	—			(59		)
Goodwill impairment charge	—			—			(492		)	—			(492		)
Total expenses	(8		)	(270		)	(3,427		)	—			(3,705		)
OPERATING (LOSS) INCOME	(8		)	(269		)	52			—			(225		)
Other income (expense), net	2			(3		)	17			—			16
Income from Group undertakings	—			409			111			(520		)	—
Expenses due to Group undertakings	—			(106		)	(414		)	520			—
Interest expense	(43		)	(77		)	(8		)	—			(128		)
LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(49		)	(46		)	(242		)	—			(337		)
Income taxes	—			65			(166		)	—			(101		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(49		)	19			(408		)	—			(438		)
Interest in earnings of associates, net of tax	—			8			(3		)	—			5
Equity account for subsidiaries	(397		)	(424		)	—			821			—
NET LOSS	(446		)	(397		)	(411		)	821			(433		)
Less: Net income attributable to noncontrolling interests	—			—			(13		)	—			(13		)
NET LOSS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	(446	)	$	(397	)	$	(424	)	$	821		$	(446	)
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2013
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
REVENUES
Commissions and fees	$	—		$	8		$	3,625		$	—		$	3,633
Investment income	—			—			15			—			15
Other income	—			—			7			—			7
Total revenues	—			8			3,647			—			3,655
EXPENSES
Salaries and benefits	(1		)	(103		)	(2,103		)	—			(2,207		)
Other operating expenses	(5		)	(232		)	(399		)	—			(636		)
Depreciation expense	—			(23		)	(71		)	—			(94		)
Amortization of intangible assets	—			—			(55		)	—			(55		)
Total expenses	(6		)	(358		)	(2,628		)	—			(2,992		)
OPERATING (LOSS) INCOME	(6		)	(350		)	1,019			—			663
Other income (expense), net	5			(4		)	31			(10		)	22
Income from Group undertakings	—			466			86			(552		)	—
Expenses due to Group undertakings	(10		)	(86		)	(456		)	552			—
Loss on extinguishment of debt	—			(60		)	—			—			(60		)
Interest expense	(42		)	(79		)	(5		)	—			(126		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(113		)	675			(10		)	499
Income taxes	—			23			(145		)	—			(122		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(90		)	530			(10		)	377
Interest in earnings of associates, net of tax	—			9			(9		)	—			—
Equity account for subsidiaries	418			498			—			(916		)	—
NET INCOME	365			417			521			(926		)	377
Less: Net income attributable to noncontrolling interests	—			—			(12		)	—			(12		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	365		$	417		$	509		$	(926	)	$	365
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	—		$	—		$	3,458		$	—		$	3,458
Investment income	—			1			—			17			—			18
Other income	—			—			—			4			—			4
Total revenues	—			1			—			3,479			—			3,480
EXPENSES
Salaries and benefits	(2		)	(96		)	—			(2,377		)	—			(2,475		)
Other operating expenses	(6		)	(158		)	—			(436		)	—			(600		)
Depreciation expense	—			(16		)	—			(63		)	—			(79		)
Amortization of intangible assets	—			—			—			(59		)	—			(59		)
Goodwill impairment	—			—			—			(492		)	—			(492		)
Total expenses	(8		)	(270		)	—			(3,427		)	—			(3,705		)
OPERATING (LOSS) INCOME	(8		)	(269		)	—			52			—			(225		)
Other income (expense), net	2			(4		)	1			17			—			16
Income from Group undertakings	—			436			79			111			(626		)	—
Expenses due to Group undertakings	—			(185		)	(27		)	(414		)	626			—
Interest expense	(43		)	(69		)	(8		)	(8		)	—			(128		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(49		)	(91		)	45			(242		)	—			(337		)
Income taxes	—			76			(11		)	(166		)	—			(101		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(49		)	(15		)	34			(408		)	—			(438		)
Interest in earnings of associates, net of tax	—			8			—			(3		)	—			5
Equity account for subsidiaries	(397		)	(390		)	(461		)	—			1,248			—
NET LOSS	(446		)	(397		)	(427		)	(411		)	1,248			(433		)
Less: Net income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
NET LOSS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	(446	)	$	(397	)	$	(427	)	$	(424	)	$	1,248		$	(446	)
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	8		$	—		$	3,625		$	—		$	3,633
Investment income	—			—			—			15			—			15
Other income	—			—			—			7			—			7
Total revenues	—			8			—			3,647			—			3,655
EXPENSES
Salaries and benefits	(1		)	(103		)	—			(2,103		)	—			(2,207		)
Other operating expenses	(5		)	(231		)	(1		)	(399		)	—			(636		)
Depreciation expense	—			(23		)	—			(71		)	—			(94		)
Amortization of intangible assets	—			—			—			(55		)	—			(55		)
Total expenses	(6		)	(357		)	(1		)	(2,628		)	—			(2,992		)
OPERATING (LOSS) INCOME	(6		)	(349		)	(1		)	1,019			—			663
Other income (expense), net	5			(4		)	—			31			(10		)	22
Income from Group undertakings	—			491			68			86			(645		)	—
Expenses due to Group undertakings	(10		)	(153		)	(26		)	(456		)	645			—
Loss on extinguishment of debt	—			(60		)	—			—			—			(60		)
Interest expense	(42		)	(61		)	(18		)	(5		)	—			(126		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(136		)	23			675			(10		)	499
Income taxes	—			29			(6		)	(145		)	—			(122		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(107		)	17			530			(10		)	377
Interest in earnings of associates, net of tax	—			9			—			(9		)	—			—
Equity account for subsidiaries	418			515			344			—			(1,277		)	—
NET INCOME	365			417			361			521			(1,287		)	377
Less: Net income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	365		$	417		$	361		$	509		$	(1,287	)	$	365
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	8		$	—		$	3,759		$	—		$	3,767
Investment income	—			—			—			16			—			16
Other income	—			—			—			19			—			19
Total revenues	—			8			—			3,794			—			3,802
EXPENSES
Salaries and benefits	(1		)	(81		)	—			(2,232		)	—			(2,314		)
Other operating expenses	(16		)	(133		)	—			(510		)	—			(659		)
Depreciation expense	—			(21		)	—			(71		)	—			(92		)
Amortization of intangible assets	—			—			—			(54		)	—			(54		)
Restructuring expenses	—			(14		)	—			(22		)	—			(36		)
Total expenses	(17		)	(249		)	—			(2,889		)	—			(3,155		)
OPERATING (LOSS) INCOME	(17		)	(241		)	—			905			—			647
Other (expense) income, net	(15		)	(220		)	—			11			230			6
Income from Group undertakings	—			450			91			102			(643		)	—
Expenses due to Group undertakings	—			(190		)	(29		)	(424		)	643			—
Interest expense	(43		)	(44		)	(36		)	(12		)	—			(135		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(245		)	26			582			230			518
Income taxes	—			54			(5		)	(208		)	—			(159		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(191		)	21			374			230			359
Interest in earnings of associates, net of tax	—			10			—			4			—			14
Equity account for subsidiaries	437			609			314			—			(1,360		)	—
NET INCOME	362			428			335			378			(1,130		)	373
Less: Net income attributable to noncontrolling interests	—			—			—			(11		)	—			(11		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	362		$	428		$	335		$	367		$	(1,130	)	$	362
Condensed Statement of Comprehensive Income [Table Text Block]	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	Comprehensive (loss) income	$	(11	)	$	69		$	(110	)	$	49		$	(3	)	$	(6	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(5		)	—			(5		)
	Comprehensive (loss) income attributable to Willis Group Holdings	$	(11	)	$	69		$	(110	)	$	44		$	(3	)	$	(11	)
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2012
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	Comprehensive loss	$	(552	)	$	(494	)	$	(263	)	$	(519	)	$	1,289		$	(539	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
	Comprehensive loss attributable to Willis Group Holdings	$	(552	)	$	(494	)	$	(263	)	$	(532	)	$	1,289		$	(552	)
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2013
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	Comprehensive income	$	522		$	565		$	74		$	636		$	(1,263	)	$	534
	Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
	Comprehensive income attributable to Willis Group Holdings	$	522		$	565		$	74		$	624		$	(1,263	)	$	522
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2014
		Willis			The Guarantors			Other			Consolidating			Consolidated
		Group									adjustments
		Holdings—the Parent Issuer
		(millions)
	Comprehensive (loss) income	$	(11	)	$	69		$	49		$	(113	)	$	(6	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			(5		)	—			(5		)
	Comprehensive (loss) income attributable to Willis Group Holdings	$	(11	)	$	69		$	44		$	(113	)	$	(11	)
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2012
		Willis			The Guarantors			Other			Consolidating			Consolidated
		Group									adjustments
		Holdings—the Parent Issuer
		(millions)
	Comprehensive loss	$	(552	)	$	(494	)	$	(519	)	$	1,026		$	(539	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			(13		)	—			(13		)
	Comprehensive loss attributable to Willis Group Holdings	$	(552	)	$	(494	)	$	(532	)	$	1,026		$	(552	)
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2013
		Willis			The Guarantors			Other			Consolidating			Consolidated
		Group									adjustments
		Holdings—the Parent Issuer
		(millions)
	Comprehensive income	$	522		$	565		$	636		$	(1,189	)	$	534
	Less: Comprehensive income attributable to noncontrolling interests	—			—			(12		)	—			(12		)
	Comprehensive income attributable to Willis Group Holdings	$	522		$	565		$	624		$	(1,189	)	$	522
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2012
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	Comprehensive loss	$	(552	)	$	(494	)	$	(528	)	$	(519	)	$	1,554		$	(539	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
	Comprehensive loss attributable to Willis Group Holdings	$	(552	)	$	(494	)	$	(528	)	$	(532	)	$	1,554		$	(552	)
	Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
Comprehensive (loss) income	$	(11	)	$	69		$	(5	)	$	49		$	(108	)	$	(6	)
Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(5		)	—			(5		)
Comprehensive (loss) income attributable to Willis Group Holdings	$	(11	)	$	69		$	(5	)	$	44		$	(108	)	$	(11	)
Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
Comprehensive income	$	522		$	565		$	504		$	636		$	(1,693	)	$	534
Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
Comprehensive income attributable to Willis Group Holdings	$	522		$	565		$	504		$	624		$	(1,693	)	$	522
Condensed Balance Sheet [Table Text Block]	Condensed Consolidating Balance Sheet
		As at December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	ASSETS
	CURRENT ASSETS
	Cash and cash equivalents	$	9		$	2		$	—		$	624		$	—		$	635
	Accounts receivable, net	—			—			4			1,040			—			1,044
	Fiduciary assets	—			—			—			8,948			—			8,948
	Deferred tax assets	—			—			—			12			—			12
	Other current assets	1			27			10			205			(29		)	214
	Amounts due from Group undertakings	3,674			924			1,057			1,114			(6,769		)	—
	Total current assets	3,684			953			1,071			11,943			(6,798		)	10,853
	NON-CURRENT ASSETS
	Investments in subsidiaries	—			2,536			721			—			(3,257		)	—
	Fixed assets, net	—			20			42			421			—			483
	Goodwill	—			—			—			2,937			—			2,937
	Other intangible assets, net	—			—			—			450			—			450
	Investments in associates	—			147			—			22			—			169
	Deferred tax assets	—			—			—			9			—			9
	Pension benefits asset	—			—			—			314			—			314
	Other non-current assets	3			8			2			207			—			220
	Non-current amounts due from Group undertakings	—			518			740			—			(1,258		)	—
	Total non-current assets	3			3,229			1,505			4,360			(4,515		)	4,582
	TOTAL ASSETS	$	3,687		$	4,182		$	2,576		$	16,303		$	(11,313	)	$	15,435
	LIABILITIES AND STOCKHOLDERS’ EQUITY
	CURRENT LIABILITIES
	Fiduciary liabilities	$	—		$	—		$	—		$	8,948		$	—		$	8,948
	Deferred revenue and accrued expenses	1			4			30			584			—			619
	Income taxes payable	—			—			7			55			(29		)	33
	Short-term debt and current portion of long-term debt	—			17			149			1			—			167
	Deferred tax liabilities	—			—			—			21			—			21
	Other current liabilities	67			11			46			320			—			444
	Amounts due to Group undertakings	—			4,374			1,499			896			(6,769		)	—
	Total current liabilities	68			4,406			1,731			10,825			(6,798		)	10,232
	NON-CURRENT LIABILITIES
	Investments in subsidiaries	838			—			—			—			(838		)	—
	Long-term debt	796			765			581			—			—			2,142
	Liabilities for pension benefits	—			—			—			284			—			284
	Deferred tax liabilities	—			—			—			128			—			128
	Provisions for liabilities	—			—			—			194			—			194
	Other non-current liabilities	—			—			17			372			—			389
	Non-current amounts due to Group undertakings	—			—			518			740			(1,258		)	—
	Total non-current liabilities	1,634			765			1,116			1,718			(2,096		)	3,137
	TOTAL LIABILITIES	$	1,702		$	5,171		$	2,847		$	12,543		$	(8,894	)	$	13,369
	Condensed Consolidating Balance Sheet
		As at December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	REDEEMABLE NONCONTROLLING INTEREST	—			—			—			59			—			59
	EQUITY
	Total Willis Group Holdings stockholders’ equity	1,985			(989		)	(271		)	3,679			(2,419		)	1,985
	Noncontrolling interests	—			—			—			22			—			22
	Total equity	1,985			(989		)	(271		)	3,701			(2,419		)	2,007
	TOTAL LIABILITIES AND EQUITY	$	3,687		$	4,182		$	2,576		$	16,303		$	(11,313	)	$	15,435
	Condensed Consolidating Balance Sheet
		As at December 31, 2013
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	3		$	3		$	—		$	790		$	—		$	796
Accounts receivable, net	—			—			4			1,037			—			1,041
Fiduciary assets	—			—			—			8,412			—			8,412
Deferred tax assets	—			—			—			16			(1		)	15
Other current assets	1			21			10			186			(21		)	197
Amounts due by group undertakings	4,051			903			1,317			1,484			(7,755		)	—
Total current assets	4,055			927			1,331			11,925			(7,777		)	10,461
NON-CURRENT ASSETS
Investments in subsidiaries	—			2,838			1,021			—			(3,859		)	—
Fixed assets, net	—			15			51			415			—			481
Goodwill	—			—			—			2,838			—			2,838
Other intangible assets, net	—			—			—			353			—			353
Investments in associates	—			156			—			20			—			176
Deferred tax assets	—			—			—			7			—			7
Pension benefits asset	—			—			—			278			—			278
Other non-current assets	4			9			5			188			—			206
Non-current amounts due by group undertakings	—			518			690			—			(1,208		)	—
Total non-current assets	4			3,536			1,767			4,099			(5,067		)	4,339
TOTAL ASSETS	$	4,059		$	4,463		$	3,098		$	16,024		$	(12,844	)	$	14,800
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,412		$	—		$	8,412
Deferred revenue and accrued expenses	2			1			28			555			—			586
Income taxes payable	—			3			—			39			(21		)	21
Short-term debt and current portion of long-term debt	—			15			—			—			—			15
Deferred tax liabilities	—			—			—			25			—			25
Other current liabilities	62			15			38			300			—			415
Amounts due to group undertakings	—			4,760			1,662			1,333			(7,755		)	—
Total current liabilities	64			4,794			1,728			10,664			(7,776		)	9,474
NON-CURRENT LIABILITIES
Investments in subsidiaries	985			—			—			—			(985		)	—
Long-term debt	795			782			733			1			—			2,311
Liabilities for pension benefits	—			—			—			136			—			136
Deferred tax liabilities	—			1			—			55			—			56
Provisions for liabilities	—			—			—			206			—			206
Other non-current liabilities	—			—			48			326			—			374
Non-current amounts due to group undertakings	—			—			518			690			(1,208		)	—
Total non-current liabilities	1,780			783			1,299			1,414			(2,193		)	3,083
TOTAL LIABILITIES	$	1,844		$	5,577		$	3,027		$	12,078		$	(9,969	)	$	12,557
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
EQUITY
Total Willis Group Holdings stockholders’ equity	2,215			(1,114		)	71			3,918			(2,875		)	2,215
Noncontrolling interests	—			—			—			28			—			28
Total equity	2,215			(1,114		)	71			3,946			(2,875		)	2,243
TOTAL LIABILITIES AND EQUITY	$	4,059		$	4,463		$	3,098		$	16,024		$	(12,844	)	$	14,800
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	9		$	2		$	624		$	—		$	635
Accounts receivable, net	—			4			1,040			—			1,044
Fiduciary assets	—			—			8,948			—			8,948
Deferred tax assets	—			—			12			—			12
Other current assets	1			37			205			(29		)	214
Amounts due from group undertakings	3,674			731			1,114			(5,519		)	—
Total current assets	3,684			774			11,943			(5,548		)	10,853
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,528			—			(3,528		)	—
Fixed assets, net	—			62			421			—			483
Goodwill	—			—			2,937			—			2,937
Other intangible assets, net	—			—			450			—			450
Investments in associates	—			147			22			—			169
Deferred tax assets	—			—			9			—			9
Pension benefits asset	—			—			314			—			314
Other non-current assets	3			10			207			—			220
Non-current amounts due from group undertakings	—			740			—			(740		)	—
Total non-current assets	3			4,487			4,360			(4,268		)	4,582
TOTAL ASSETS	$	3,687		$	5,261		$	16,303		$	(9,816	)	$	15,435
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	8,948		$	—		$	8,948
Deferred revenue and accrued expenses	1			34			584			—			619
Income taxes payable	—			7			55			(29		)	33
Short-term debt and current portion on long-term debt	—			166			1			—			167
Deferred tax liabilities	—			—			21			—			21
Other current liabilities	67			57			320			—			444
Amounts due to group undertakings	—			4,623			896			(5,519		)	—
Total current liabilities	68			4,887			10,825			(5,548		)	10,232
NON-CURRENT LIABILITIES
Investments in subsidiaries	838			—			—			(838		)	—
Long-term debt	796			1,346			—			—			2,142
Liabilities for pension benefits	—			—			284			—			284
Deferred tax liabilities	—			—			128			—			128
Provisions for liabilities	—			—			194			—			194
Other non-current liabilities	—			17			372			—			389
Non-current amounts due to group undertakings	—			—			740			(740		)	—
Total non-current liabilities	1,634			1,363			1,718			(1,578		)	3,137
TOTAL LIABILITIES	$	1,702		$	6,250		$	12,543		$	(7,126	)	$	13,369
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
REDEEMABLE NONCONTROLLING INTEREST	—			—			59			—			59
EQUITY
Total Willis Group Holdings stockholders’ equity	1,985			(989		)	3,679			(2,690		)	1,985
Noncontrolling interests	—			—			22			—			22
Total equity	1,985			(989		)	3,701			(2,690		)	2,007
TOTAL LIABILITIES AND EQUITY	$	3,687		$	5,261		$	16,303		$	(9,816	)	$	15,435
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	3		$	3		$	790		$	—		$	796
Accounts receivable, net	—			4			1,037			—			1,041
Fiduciary assets	—			—			8,412			—			8,412
Deferred tax assets	—			—			16			(1		)	15
Other current assets	1			31			186			(21		)	197
Amounts due from group undertakings	4,051			975			1,484			(6,510		)	—
Total current assets	4,055			1,013			11,925			(6,532		)	10,461
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,788			—			(3,788		)	—
Fixed assets, net	—			66			415			—			481
Goodwill	—			—			2,838			—			2,838
Other intangible assets, net	—			—			353			—			353
Investments in associates	—			156			20			—			176
Deferred tax assets	—			—			7			—			7
Pension benefits asset	—			—			278			—			278
Other non-current assets	4			14			188			—			206
Non-current amounts due from group undertakings	—			690			—			(690		)	—
Total non-current assets	4			4,714			4,099			(4,478		)	4,339
TOTAL ASSETS	$	4,059		$	5,727		$	16,024		$	(11,010	)	$	14,800
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	8,412		$	—		$	8,412
Deferred revenue and accrued expenses	2			29			555			—			586
Income taxes payable	—			3			39			(21		)	21
Short-term debt and current portion of long-term debt	—			15			—			—			15
Deferred tax liabilities	—			—			25			—			25
Other current liabilities	62			53			300			—			415
Amounts due to group undertakings	—			5,177			1,333			(6,510		)	—
Total current liabilities	64			5,277			10,664			(6,531		)	9,474
NON-CURRENT LIABILITIES
Investments in subsidiaries	985			—			—			(985		)	—
Long-term debt	795			1,515			1			—			2,311
Liabilities for pension benefits	—			—			136			—			136
Deferred tax liabilities	—			1			55			—			56
Provisions for liabilities	—			—			206			—			206
Other non-current liabilities	—			48			326			—			374
Non-current amounts due to group undertakings	—			—			690			(690		)	—
Total non-current liabilities	1,780			1,564			1,414			(1,675		)	3,083
TOTAL LIABILITIES	$	1,844		$	6,841		$	12,078		$	(8,206	)	$	12,557
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
EQUITY
Total Willis Group Holdings stockholders’ equity	2,215			(1,114		)	3,918			(2,804		)	2,215
Noncontrolling interests	—			—			28			—			28
Total equity	2,215			(1,114		)	3,946			(2,804		)	2,243
TOTAL LIABILITIES AND EQUITY	$	4,059		$	5,727		$	16,024		$	(11,010	)	$	14,800
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	9		$	2		$	—		$	624		$	—		$	635
Accounts receivable, net	—			4			—			1,040			—			1,044
Fiduciary assets	—			—			—			8,948			—			8,948
Deferred tax assets	—			—			—			12			—			12
Other current assets	1			41			1			205			(34		)	214
Amounts due from group undertakings	3,674			1,154			797			1,114			(6,739		)	—
Total current assets	3,684			1,201			798			11,943			(6,773		)	10,853
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,478			2,578			—			(6,056		)	—
Fixed assets, net	—			62			—			421			—			483
Goodwill	—			—			—			2,937			—			2,937
Other intangible assets, net	—			—			—			450			—			450
Investments in associates	—			147			—			22			—			169
Deferred tax assets	—			—			—			9			—			9
Pension benefits asset	—			—			—			314			—			314
Other non-current assets	3			2			8			207			—			220
Non-current amounts due from group undertakings	—			740			518			—			(1,258		)	—
Total non-current assets	3			4,429			3,104			4,360			(7,314		)	4,582
TOTAL ASSETS	$	3,687		$	5,630		$	3,902		$	16,303		$	(14,087	)	$	15,435
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,948		$	—		$	8,948
Deferred revenue and accrued expenses	1			34			—			584			—			619
Income taxes payable	—			7			5			55			(34		)	33
Short-term debt and current portion of long-term debt	—			149			17			1			—			167
Deferred tax liabilities	—			—			—			21			—			21
Other current liabilities	67			46			11			320			—			444
Amounts due to group undertakings	—			5,267			576			896			(6,739		)	—
Total current liabilities	68			5,503			609			10,825			(6,773		)	10,232
NON-CURRENT LIABILITIES
Investments in subsidiaries	838			—			—			—			(838		)	—
Long-term debt	796			581			765			—			—			2,142
Liabilities for pension benefits	—			—			—			284			—			284
Deferred tax liabilities	—			—			—			128			—			128
Provisions for liabilities	—			—			—			194			—			194
Other non-current liabilities	—			17			—			372			—			389
Non-current amounts due to group undertakings	—			518			—			740			(1,258		)	—
Total non-current liabilities	1,634			1,116			765			1,718			(2,096		)	3,137
TOTAL LIABILITIES	$	1,702		$	6,619		$	1,374		$	12,543		$	(8,869	)	$	13,369
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REDEEMABLE NONCONTROLLING INTEREST	—			—			—			59			—			59
EQUITY
Total Willis Group Holdings stockholders’ equity	1,985			(989		)	2,528			3,679			(5,218		)	1,985
Noncontrolling interests	—			—			—			22			—			22
Total equity	1,985			(989		)	2,528			3,701			(5,218		)	2,007
TOTAL LIABILITIES AND EQUITY	$	3,687		$	5,630		$	3,902		$	16,303		$	(14,087	)	$	15,435
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	3		$	3		$	—		$	790		$	—		$	796
Accounts receivable, net	—			4			—			1,037			—			1,041
Fiduciary assets	—			—			—			8,412			—			8,412
Deferred tax assets	—			—			—			16			(1		)	15
Other current assets	1			36			1			186			(27		)	197
Amounts due from group undertakings	4,051			975			793			1,484			(7,303		)	—
Total current assets	4,055			1,018			794			11,925			(7,331		)	10,461
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,716			2,705			—			(6,421		)	—
Fixed assets, net	—			66			—			415			—			481
Goodwill	—			—			—			2,838			—			2,838
Other intangible assets, net	—			—			—			353			—			353
Investments in associates	—			156			—			20			—			176
Deferred tax assets	—			—			—			7			—			7
Pension benefits asset	—			—			—			278			—			278
Other non-current assets	4			5			9			188			—			206
Non-current amounts due from group undertakings	—			1,113			518			—			(1,631		)	—
Total non-current assets	4			5,056			3,232			4,099			(8,052		)	4,339
TOTAL ASSETS	$	4,059		$	6,074		$	4,026		$	16,024		$	(15,383	)	$	14,800
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,412		$	—		$	8,412
Deferred revenue and accrued expenses	2			29			—			555			—			586
Income taxes payable	—			4			5			39			(27		)	21
Short-term debt and current portion of long-term debt	—			—			15			—			—			15
Deferred tax liabilities	—			—			—			25			—			25
Other current liabilities	62			42			11			300			—			415
Amounts due to group undertakings	—			5,813			157			1,333			(7,303		)	—
Total current liabilities	64			5,888			188			10,664			(7,330		)	9,474
NON-CURRENT LIABILITIES
Investments in subsidiaries	985			—			—			—			(985		)	—
Long-term debt	795			733			782			1			—			2,311
Liabilities for pension benefits	—			—			—			136			—			136
Deferred tax liabilities	—			1			—			55			—			56
Provisions for liabilities	—			—			—			206			—			206
Other non-current liabilities	—			48			—			326			—			374
Non-current amounts due to group undertakings	—			518			423			690			(1,631		)	—
Total non-current liabilities	1,780			1,300			1,205			1,414			(2,616		)	3,083
TOTAL LIABILITIES	$	1,844		$	7,188		$	1,393		$	12,078		$	(9,946	)	$	12,557
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
EQUITY
Total Willis Group Holdings stockholders’ equity	2,215			(1,114		)	2,633			3,918			(5,437		)	2,215
Noncontrolling interests	—			—			—			28			—			28
Total equity	2,215			(1,114		)	2,633			3,946			(5,437		)	2,243
TOTAL LIABILITIES AND EQUITY	$	4,059		$	6,074		$	4,026		$	16,024		$	(15,383	)	$	14,800
Condensed Cash Flow Statement [Table Text Block]	Condensed Consolidating Statement of Cash Flows
		Year Ended December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(35	)	$	387		$	265		$	212		$	(352	)	$	477
	CASH FLOWS FROM INVESTING ACTIVITIES
	Proceeds on disposal of fixed and intangible assets	—			—			1			6			(1		)	6
	Additions to fixed assets	—			(9		)	(10		)	(95		)	1			(113		)
	Additions to intangibles assets	—			—			—			(4		)	—			(4		)
	Acquisitions of subsidiaries, net of cash acquired	—			—			—			(241		)	—			(241		)
	Payments to acquire other investments	—			—			—			(10		)	—			(10		)
	Proceeds from sale of operations, net of cash disposed	—			—			—			86			—			86
	Proceeds from intercompany investing activities	361			—			120			435			(916		)	—
	Repayments of intercompany investing activities	—			(53		)	(131		)	(46		)	230			—
	Additional investment in subsidiaries	(31		)	—			—			—			31			—
	Net cash provided by (used in) investing activities	330			(62		)	(20		)	131			(655		)	(276		)
	CASH FLOWS FROM FINANCING ACTIVITIES
	Debt issuance costs	—			—			—			(3		)	—			(3		)
	Repayments of debt	—			(15		)	—			—			—			(15		)
	Repurchase of shares	(213		)	—			—			—			—			(213		)
	Proceeds from issue of shares	134			—			—			31			(31		)	134
	Excess tax benefits from share-based payment arrangements	—			—			—			5			—			5
	Dividends paid	(210		)	—			—			(352		)	352			(210		)
	Acquisition of noncontrolling interests	—			(4		)	—			—			—			(4		)
	Dividends paid to noncontrolling interests	—			—			—			(17		)	—			(17		)
	Proceeds from intercompany financing activities	—			46			4			180			(230		)	—
	Repayments of intercompany financing activities	—			(353		)	(249		)	(314		)	916			—
	Net cash used in financing activities	(289		)	(326		)	(245		)	(470		)	1,007			(323		)
	INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	6			(1		)	—			(127		)	—			(122		)
	Effect of exchange rate changes on cash and cash equivalents	—			—			—			(39		)	—			(39		)
	CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3			3			—			790			—			796
	CASH AND CASH EQUIVALENTS, END OF YEAR	$	9		$	2		$	—		$	624		$	—		$	635
	Condensed Consolidating Statement of Cash Flows
		Year Ended December 31, 2013
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	NET CASH PROVIDED BY OPERATING ACTIVITIES	$	4		$	125		$	7		$	662		$	(237	)	$	561
	CASH FLOWS FROM INVESTING ACTIVITIES
	Proceeds on disposal of fixed and intangible assets	—			—			3			9			—			12
	Additions to fixed assets	—			(7		)	(11		)	(94		)	—			(112		)
	Additions to intangible assets	—			—			—			(7		)	—			(7		)
	Acquisitions of subsidiaries, net of cash acquired	—			(237		)	(230		)	(30		)	467			(30		)
	Payments to acquire other investments	—			—			—			(7		)	—			(7		)
	Proceeds from sale of associates	—			—			—			4			—			4
	Proceeds from sale of operations, net of cash disposed	—			—			230			257			(467		)	20
	Proceeds from intercompany investing activities	383			211			36			60			(690		)	—
	Repayments of intercompany investing activities	(347		)	(442		)	(120		)	(780		)	1,689			—
	Net cash provided by (used in) investing activities	36			(475		)	(92		)	(588		)	999			(120		)
	CASH FLOWS FROM FINANCING ACTIVITIES
	Senior notes issued	—			522			—			—			—			522
	Debt issuance costs	—			(8		)	—			—			—			(8		)
	Repayments of debt	—			(15		)	(521		)	—			—			(536		)
	Tender premium on extinguishment of senior notes	—			—			(65		)	—			—			(65		)
	Proceeds from issue of shares	155			—			—			—			—			155
	Excess tax benefits from share-based payment arrangements	—			—			—			2			—			2
	Dividends paid	(193		)	—			(230		)	(7		)	237			(193		)
	Acquisition of noncontrolling interests	—			—			—			(4		)	—			(4		)
	Dividends paid to noncontrolling interests	—			—			—			(10		)	—			(10		)
	Proceeds from intercompany financing activities	—			321			901			467			(1,689		)	—
	Repayments of intercompany financing activities	—			(467		)	—			(223		)	690			—
Net cash (used in) provided by financing activities	(38		)	353			85			225			(762		)	(137		)
INCREASE IN CASH AND CASH EQUIVALENTS	2			3			—			299			—			304
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(8		)	—			(8		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	1			—			—			499			—			500
CASH AND CASH EQUIVALENTS, END OF YEAR	$	3		$	3		$	—		$	790		$	—		$	796
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(23	)	$	1,504		$	(44	)	$	(97	)	$	(815	)	$	525
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			—			5			—			5
Additions to fixed assets	—			(7		)	(19		)	(109		)	—			(135		)
Additions to intangible assets	—			—			—			(2		)	—			(2		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(33		)	—			(33		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from intercompany investing activities	256			216			44			1,230			(1,746		)	—
Repayments of intercompany investing activities	—			(318		)	(10		)	(81		)	409			—
Net cash provided by (used in) investing activities	256			(109		)	15			1,003			(1,337		)	(172		)
CASH FLOWS FROM FINANCING ACTIVITIES
Repayments of debt	—			(15		)	—			—			—			(15		)
Proceeds from issue of other debt	—			1			—			—			—			1
Repurchase of shares	(100		)	—			—			—			—			(100		)
Proceeds from issue of shares	53			—			—			—			—			53
Excess tax benefits from share-based payment arrangements	—			—			—			2			—			2
Dividends paid	(185		)	—			—			(815		)	815			(185		)
Proceeds from sale of noncontrolling interest	—			—			—			3			—			3
Acquisition of noncontrolling interests	—			—			—			(39		)	—			(39		)
Dividends paid to noncontrolling interests	—			—			—			(11		)	—			(11		)
Cash received on intercompany financing activities	—			81			—			328			(409		)	—
Cash paid on intercompany financing activities	—			(1,462		)	(134		)	(150		)	1,746			—
Net cash used in financing activities	(232		)	(1,395		)	(134		)	(682		)	2,152			(291		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1			—			(163		)	224			—			62
Effect of exchange rate changes on cash and cash equivalents	—			—			—			2			—			2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	—			—			163			273			—			436
CASH AND CASH EQUIVALENTS, END OF YEAR	$	1		$	—		$	—		$	499		$	—		$	500
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2014
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(35	)	$	652		$	212		$	(352	)	$	477
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			1			6			(1		)	6
Additions to fixed assets	—			(19		)	(95		)	1			(113		)
Additions to intangibles assets	—			—			(4		)	—			(4		)
Acquisitions of subsidiaries, net of cash acquired	—			—			(241		)	—			(241		)
Payments to acquire other investments	—			—			(10		)	—			(10		)
Proceeds from disposal of operations, net of cash disposed	—			—			86			—			86
Proceeds from intercompany investing activities	361			120			435			(916		)	—
Repayments of intercompany investing activities	—			(180		)	(46		)	226			—
Additional investment in subsidiaries	(31		)	—			—			31			—
Net cash provided by (used in) investing activities	330			(78		)	131			(659		)	(276		)
CASH FLOWS FROM FINANCING ACTIVITIES
Debt issuance costs	—			—			(3		)	—			(3		)
Repayments of debt	—			(15		)	—			—			(15		)
Repurchase of shares	(213		)	—			—			—			(213		)
Proceeds from the issue of shares	134			—			31			(31		)	134
Excess tax benefits from share-based payment arrangements	—			—			5			—			5
Dividends paid	(210		)	—			(352		)	352			(210		)
Acquisition of noncontrolling interests	—			(4		)	—			—			(4		)
Dividends paid to noncontrolling interests	—			—			(17		)	—			(17		)
Proceeds from intercompany financing activities	—			46			180			(226		)	—
Repayments of intercompany financing activities	—			(602		)	(314		)	916			—
Net cash used in financing activities	(289		)	(575		)	(470		)	1,011			(323		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	6			(1		)	(127		)	—			(122		)
Effect of exchange rate changes on cash and cash equivalents	—			—			(39		)	—			(39		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3			3			790			—			796
CASH AND CASH EQUIVALENTS, END OF YEAR	$	9		$	2		$	624		$	—		$	635
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2013
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES	$	4		$	(98	)	$	662		$	(7	)	$	561
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			3			9			—			12
Additions to fixed assets	—			(18		)	(94		)	—			(112		)
Additions to intangible assets	—			—			(7		)	—			(7		)
Acquisitions of subsidiaries, net of cash acquired	—			(237		)	(30		)	237			(30		)
Payments to acquire other investments	—			—			(7		)	—			(7		)
Proceeds from sale of associates	—			—			4			—			4
Proceeds from sale of operations, net of cash disposed	—			—			257			(237		)	20
Proceeds from intercompany investing activities	383			223			60			(666		)	—
Repayments of intercompany investing activities	(347		)	(120		)	(780		)	1,247			—
Net cash provided by (used in) investing activities	36			(149		)	(588		)	581			(120		)
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued	—			522			—			—			522
Debt issuance costs	—			(8		)	—			—			(8		)
Repayments of debt	—			(536		)	—			—			(536		)
Tender premium on extinguishment of senior notes	—			(65		)	—			—			(65		)
Proceeds from the issue of shares	155			—			—			—			155
Excess tax benefits from share-based payment arrangements	—			—			2			—			2
Dividends paid	(193		)	—			(7		)	7			(193		)
Acquisition of noncontrolling interests	—			—			(4		)	—			(4		)
Dividends paid to noncontrolling interests	—			—			(10		)	—			(10		)
Proceeds from intercompany financing activities	—			780			467			(1,247		)	—
Repayments of intercompany financing activities	—			(443		)	(223		)	666			—
Net cash (used in) provided by financing activities	(38		)	250			225			(574		)	(137		)
INCREASE IN CASH AND CASH EQUIVALENTS	2			3			299			—			304
Effect of exchange rate changes on cash and cash equivalents	—			—			(8		)	—			(8		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	1			—			499			—			500
CASH AND CASH EQUIVALENTS, END OF YEAR	$	3		$	3		$	790		$	—		$	796
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2012
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
NET CASH (USED IN) PROVIDED BY OPERATING	$	(23	)	$	1,460		$	(97	)	$	(815	)	$	525
ACTIVITIES
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			5			—			5
Additions to fixed assets	—			(26		)	(109		)	—			(135		)
Additions to intangible assets	—			—			(2		)	—			(2		)
Acquisitions of subsidiaries, net of cash acquired	—			—			(33		)	—			(33		)
Payments to acquire other investments	—			—			(7		)	—			(7		)
Proceeds from intercompany investing activities	256			150			1,230			(1,636		)	—
Repayments of intercompany investing activities	—			(328		)	(81		)	409			—
Net cash provided by (used in) investing activities	256			(204		)	1,003			(1,227		)	(172		)
CASH FLOWS FROM FINANCING ACTIVITIES
Repayments of debt	—			(15		)	—			—			(15		)
Proceeds from the issue of other debt	—			1			—			—			1
Repurchase of shares	(100		)	—			—			—			(100		)
Proceeds from issue of shares	53			—			—			—			53
Excess tax benefits from share-based payment arrangements	—			—			2			—			2
Dividends paid	(185		)	—			(815		)	815			(185		)
Proceeds from sale of noncontrolling interest	—			—			3			—			3
Acquisition of noncontrolling interests	—			—			(39		)	—			(39		)
Dividends paid to noncontrolling interests	—			—			(11		)	—			(11		)
Proceeds from intercompany financing activities	—			81			328			(409		)	—
Repayments of intercompany financing activities	—			(1,486		)	(150		)	1,636			—
Net cash used in financing activities	(232		)	(1,419		)	(682		)	2,042			(291		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1			(163		)	224			—			62
Effect of exchange rate changes on cash and cash equivalents	—			—			2			—			2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	—			163			273			—			436
CASH AND CASH EQUIVALENTS, END OF YEAR	$	1		$	—		$	499		$	—		$	500
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(35	)	$	781		$	181		$	212		$	(662	)	$	477
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			1			—			6			(1		)	6
Additions to fixed assets	—			(19		)	—			(95		)	1			(113		)
Additions to intangible assets	—			—			—			(4		)	—			(4		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(241		)	—			(241		)
Payments to acquire other investments	—			—			—			(10		)	—			(10		)
Proceeds from sale of operations, net of cash disposed	—			—			—			86			—			86
Proceeds from intercompany investing activities	361			120			—			435			(916		)	—
Repayments of intercompany investing activities	—			(180		)	(4		)	(46		)	230			—
Additional investment in subsidiaries	(31		)	—			—			—			31			—
Net cash provided by (used in) investing activities	330			(78		)	(4		)	131			(655		)	(276		)
CASH FLOWS FROM FINANCING ACTIVITIES
Debt issuance costs	—			—			—			(3		)	—			(3		)
Repayments of debt	—			—			(15		)	—			—			(15		)
Repurchase of shares	(213		)	—			—			—			—			(213		)
Proceeds from issue of shares	134			—			—			31			(31		)	134
Excess tax benefits from share-based payment arrangement	—			—			—			5			—			5
Dividends paid	(210		)	(155		)	(155		)	(352		)	662			(210		)
Acquisition of noncontrolling interests	—			(4		)	—			—			—			(4		)
Dividends paid to noncontrolling interests	—			—			—			(17		)	—			(17		)
Proceeds from intercompany financing activities	—			50			—			180			(230		)	—
Repayments of intercompany financing activities	—			(595		)	(7		)	(314		)	916			—
Net cash used in financing activities	(289		)	(704		)	(177		)	(470		)	1,317			(323		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	6			(1		)	—			(127		)	—			(122		)
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(39		)	—			(39		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3			3			—			790			—			796
CASH AND CASH EQUIVALENTS, END OF YEAR	$	9		$	2		$	—		$	624		$	—		$	635
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH PROVIDED BY OPERATING ACTIVITIES	$	4		$	399		$	63		$	662		$	(567	)	$	561
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			3			—			9			—			12
Additions to fixed assets	—			(18		)	—			(94		)	—			(112		)
Additions to intangible assets	—			—			—			(7		)	—			(7		)
Acquisitions of subsidiaries, net of cash acquired	—			(237		)	—			(30		)	237			(30		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from sale of associates	—			—			—			4			—			4
Proceeds from sale of operations, net of cash disposed	—			—			—			257			(237		)	20
Proceeds from intercompany investing activities	383			160			132			60			(735		)	—
Repayments of intercompany investing activities	(347		)	(120		)	(442		)	(780		)	1,689			—
Net cash provided by (used in) investing activities	36			(212		)	(310		)	(588		)	954			(120		)
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued	—			—			522			—			—			522
Debt issuance costs	—			—			(8		)	—			—			(8		)
Repayments of debt	—			(521		)	(15		)	—			—			(536		)
Tender premium on extinguishment of senior notes	—			(65		)	—			—			—			(65		)
Proceeds from issue of shares	155			—			—			—			—			155
Excess tax benefits from share-based payment arrangement	—			—			—			2			—			2
Dividends paid	(193		)	(230		)	(330		)	(7		)	567			(193		)
Acquisition of noncontrolling interests	—			—			—			(4		)	—			(4		)
Dividends paid to noncontrolling interests	—			—			—			(10		)	—			(10		)
Proceeds from intercompany financing activities	—			1,075			147			467			(1,689		)	—
Repayments of intercompany financing activities	—			(443		)	(69		)	(223		)	735			—
Net cash (used in) provided by financing activities	(38		)	(184		)	247			225			(387		)	(137		)
INCREASE IN CASH AND CASH EQUIVALENTS	2			3			—			299			—			304
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(8		)	—			(8		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	1			—			—			499			—			500
CASH AND CASH EQUIVALENTS, END OF YEAR	$	3		$	3		$	—		$	790		$	—		$	796
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(23	)	$	2,393		$	1,356		$	(97	)	$	(3,104	)	$	525
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			—			5			—			5
Additions to fixed assets	—			(26		)	—			(109		)	—			(135		)
Additions to intangible assets	—			—			—			(2		)	—			(2		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(33		)	—			(33		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from intercompany investing activities	256			176			78			1,230			(1,740		)	—
Repayments of intercompany investing activities	—			(197		)	(131		)	(81		)	409			—
Net cash provided by (used in) investing activities	256			(47		)	(53		)	1,003			(1,331		)	(172		)
CASH FLOWS FROM FINANCING ACTIVITIES
Repayments of debt	—			(4		)	(11		)	—			—			(15		)
Proceeds from issue of other debt	—			—			1			—			—			1
Repurchase of shares	(100		)	—			—			—			—			(100		)
Proceeds from issue of shares	53			—			—			—			—			53
Excess tax benefits from share-based payment arrangements	—			—			—			2			—			2
Dividends paid	(185		)	(1,220		)	(1,069		)	(815		)	3,104			(185		)
Proceeds from sale of noncontrolling interests	—			—			—			3			—			3
Acquisition of noncontrolling interests	—			—			—			(39		)	—			(39		)
Dividends paid to noncontrolling interests	—			—			—			(11		)	—			(11		)
Proceeds from intercompany financing activities	—			81			—			328			(409		)	—
Repayments of intercompany financing activities	—			(1,366		)	(224		)	(150		)	1,740			—
Net cash used in financing activities	(232		)	(2,509		)	(1,303		)	(682		)	4,435			(291		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1			(163		)	—			224			—			62
Effect of exchange rate changes on cash and cash equivalents	—			—			—			2			—			2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	—			163			—			273			—			436
CASH AND CASH EQUIVALENTS, END OF YEAR	$	1		$	—		$	—		$	499		$	—		$	500

Financial_Information_for_Issu1

Financial Information for Issuer, Parent Guarantor, Other Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Tables)	12 Months Ended
	Dec. 31, 2014
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Income Statement [Table Text Block]	Condensed Consolidating Statement of Operations
		Year Ended December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	REVENUES
	Commissions and fees	$	—		$	—		$	8		$	3,759		$	—		$	3,767
	Investment income	—			—			—			16			—			16
	Other income	—			—			—			19			—			19
	Total revenues	—			—			8			3,794			—			3,802
	EXPENSES
	Salaries and benefits	(1		)	—			(81		)	(2,232		)	—			(2,314		)
	Other operating expenses	(16		)	(95		)	(38		)	(510		)	—			(659		)
	Depreciation expense	—			(4		)	(17		)	(71		)	—			(92		)
	Amortization of intangible assets	—			—			—			(54		)	—			(54		)
	Restructuring costs	—			(11		)	(3		)	(22		)	—			(36		)
	Total expenses	(17		)	(110		)	(139		)	(2,889		)	—			(3,155		)
	OPERATING (LOSS) INCOME	(17		)	(110		)	(131		)	905			—			647
	Other (expense) income, net	(15		)	(220		)	—			11			230			6
	Income from Group undertakings	—			221			313			102			(636		)	—
	Expenses due to Group undertakings	—			(33		)	(179		)	(424		)	636			—
	Interest expense	(43		)	(35		)	(45		)	(12		)	—			(135		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(177		)	(42		)	582			230			518
	Income taxes	—			25			24			(208		)	—			(159		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(152		)	(18		)	374			230			359
	Interest in earnings of associates, net of tax	—			10			—			4			—			14
	Equity account for subsidiaries	437			570			76			—			(1,083		)	—
	NET INCOME	362			428			58			378			(853		)	373
	Less: Net loss attributable to noncontrolling interests	—			—			—			(11		)	—			(11		)
	NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	362		$	428		$	58		$	367		$	(853	)	$	362
	Condensed Consolidating Statement of Operations
		Year Ended December 31, 2012
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	REVENUES
	Commissions and fees	$	—		$	—		$	—		$	3,458		$	—		$	3,458
	Investment income	—			—			1			17			—			18
	Other income	—			—			—			4			—			4
	Total revenues	—			—			1			3,479			—			3,480
	EXPENSES
	Salaries and benefits	(2		)	—			(96		)	(2,377		)	—			(2,475		)
	Other operating expenses	(6		)	(80		)	(78		)	(436		)	—			(600		)
	Depreciation expense	—			(1		)	(15		)	(63		)	—			(79		)
	Amortization of intangible assets	—			—			—			(59		)	—			(59		)
	Goodwill impairment charge	—			—			—			(492		)	—			(492		)
	Total expenses	(8		)	(81		)	(189		)	(3,427		)	—			(3,705		)
	OPERATING (LOSS) INCOME	(8		)	(81		)	(188		)	52			—			(225		)
	Other income (expense), net	2			(2		)	(1		)	17			—			16
	Income from Group undertakings	—			201			316			111			(628		)	—
	Expenses due to Group undertakings	—			(67		)	(147		)	(414		)	628			—
	Interest expense	(43		)	(7		)	(70		)	(8		)	—			(128		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(49		)	44			(90		)	(242		)	—			(337		)
	Income taxes	—			31			34			(166		)	—			(101		)
	(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(49		)	75			(56		)	(408		)	—			(438		)
	Interest in earnings of associates, net of tax	—			8			—			(3		)	—			5
	Equity account for subsidiaries	(397		)	(480		)	(172		)	—			1,049			—
	NET LOSS	(446		)	(397		)	(228		)	(411		)	1,049			(433		)
	Less: Net income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
	NET LOSS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	(446	)	$	(397	)	$	(228	)	$	(424	)	$	1,049		$	(446	)
	Condensed Consolidating Statement of Operations
		Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	—		$	8		$	3,625		$	—		$	3,633
Investment income	—			—			—			15			—			15
Other income	—			—			—			7			—			7
Total revenues	—			—			8			3,647			—			3,655
EXPENSES
Salaries and benefits	(1		)	—			(103		)	(2,103		)	—			(2,207		)
Other operating expenses	(5		)	(69		)	(163		)	(399		)	—			(636		)
Depreciation expense	—			(3		)	(20		)	(71		)	—			(94		)
Amortization of intangible assets	—			—			—			(55		)	—			(55		)
Total expenses	(6		)	(72		)	(286		)	(2,628		)	—			(2,992		)
OPERATING (LOSS) INCOME	(6		)	(72		)	(278		)	1,019			—			663
Other income (expense), net	5			(4		)	—			31			(10		)	22
Income from Group undertakings	—			191			364			86			(641		)	—
Expenses due to Group undertakings	(10		)	(34		)	(141		)	(456		)	641			—
Loss on extinguishment of debt	—			—			(60		)	—			—			(60		)
Interest expense	(42		)	(16		)	(63		)	(5		)	—			(126		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(53		)	65			(178		)	675			(10		)	499
Income taxes	—			23			—			(145		)	—			(122		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(53		)	88			(178		)	530			(10		)	377
Interest in earnings of associates, net of tax	—			9			—			(9		)	—			—
Equity account for subsidiaries	418			320			150			—			(888		)	—
NET INCOME (LOSS)	365			417			(28		)	521			(898		)	377
Less: Net income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
NET INCOME (LOSS) ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	365		$	417		$	(28	)	$	509		$	(898	)	$	365
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2014
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
REVENUES
Commissions and fees	$	—		$	8		$	3,759		$	—		$	3,767
Investment income	—			—			16			—			16
Other income	—			—			19			—			19
Total revenues	—			8			3,794			—			3,802
EXPENSES
Salaries and benefits	(1		)	(81		)	(2,232		)	—			(2,314		)
Other operating expenses	(16		)	(133		)	(510		)	—			(659		)
Depreciation expense	—			(21		)	(71		)	—			(92		)
Amortization of intangible assets	—			—			(54		)	—			(54		)
Restructuring expenses	—			(14		)	(22		)	—			(36		)
Total expenses	(17		)	(249		)	(2,889		)	—			(3,155		)
OPERATING (LOSS) INCOME	(17		)	(241		)	905			—			647
Other (expense) income, net	(15		)	(220		)	11			230			6
Income from Group undertakings	—			424			102			(526		)	—
Expenses due to Group undertakings	—			(102		)	(424		)	526			—
Interest expense	(43		)	(80		)	(12		)	—			(135		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(219		)	582			230			518
Income taxes	—			49			(208		)	—			(159		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(170		)	374			230			359
Interest in earnings of associates, net of tax	—			10			4			—			14
Equity account for subsidiaries	437			588			—			(1,025		)	—
NET INCOME	362			428			378			(795		)	373
Less: Net income attributable to noncontrolling interests	—			—			(11		)	—			(11		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	362		$	428		$	367		$	(795	)	$	362
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2012
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
REVENUES
Commissions and fees	$	—		$	—		$	3,458		$	—		$	3,458
Investment income	—			1			17			—			18
Other income	—			—			4			—			4
Total revenues	—			1			3,479			—			3,480
EXPENSES
Salaries and benefits	(2		)	(96		)	(2,377		)	—			(2,475		)
Other operating expenses	(6		)	(158		)	(436		)	—			(600		)
Depreciation expense	—			(16		)	(63		)	—			(79		)
Amortization of intangible assets	—			—			(59		)	—			(59		)
Goodwill impairment charge	—			—			(492		)	—			(492		)
Total expenses	(8		)	(270		)	(3,427		)	—			(3,705		)
OPERATING (LOSS) INCOME	(8		)	(269		)	52			—			(225		)
Other income (expense), net	2			(3		)	17			—			16
Income from Group undertakings	—			409			111			(520		)	—
Expenses due to Group undertakings	—			(106		)	(414		)	520			—
Interest expense	(43		)	(77		)	(8		)	—			(128		)
LOSS FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(49		)	(46		)	(242		)	—			(337		)
Income taxes	—			65			(166		)	—			(101		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(49		)	19			(408		)	—			(438		)
Interest in earnings of associates, net of tax	—			8			(3		)	—			5
Equity account for subsidiaries	(397		)	(424		)	—			821			—
NET LOSS	(446		)	(397		)	(411		)	821			(433		)
Less: Net income attributable to noncontrolling interests	—			—			(13		)	—			(13		)
NET LOSS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	(446	)	$	(397	)	$	(424	)	$	821		$	(446	)
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2013
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
REVENUES
Commissions and fees	$	—		$	8		$	3,625		$	—		$	3,633
Investment income	—			—			15			—			15
Other income	—			—			7			—			7
Total revenues	—			8			3,647			—			3,655
EXPENSES
Salaries and benefits	(1		)	(103		)	(2,103		)	—			(2,207		)
Other operating expenses	(5		)	(232		)	(399		)	—			(636		)
Depreciation expense	—			(23		)	(71		)	—			(94		)
Amortization of intangible assets	—			—			(55		)	—			(55		)
Total expenses	(6		)	(358		)	(2,628		)	—			(2,992		)
OPERATING (LOSS) INCOME	(6		)	(350		)	1,019			—			663
Other income (expense), net	5			(4		)	31			(10		)	22
Income from Group undertakings	—			466			86			(552		)	—
Expenses due to Group undertakings	(10		)	(86		)	(456		)	552			—
Loss on extinguishment of debt	—			(60		)	—			—			(60		)
Interest expense	(42		)	(79		)	(5		)	—			(126		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(113		)	675			(10		)	499
Income taxes	—			23			(145		)	—			(122		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(90		)	530			(10		)	377
Interest in earnings of associates, net of tax	—			9			(9		)	—			—
Equity account for subsidiaries	418			498			—			(916		)	—
NET INCOME	365			417			521			(926		)	377
Less: Net income attributable to noncontrolling interests	—			—			(12		)	—			(12		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	365		$	417		$	509		$	(926	)	$	365
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	—		$	—		$	3,458		$	—		$	3,458
Investment income	—			1			—			17			—			18
Other income	—			—			—			4			—			4
Total revenues	—			1			—			3,479			—			3,480
EXPENSES
Salaries and benefits	(2		)	(96		)	—			(2,377		)	—			(2,475		)
Other operating expenses	(6		)	(158		)	—			(436		)	—			(600		)
Depreciation expense	—			(16		)	—			(63		)	—			(79		)
Amortization of intangible assets	—			—			—			(59		)	—			(59		)
Goodwill impairment	—			—			—			(492		)	—			(492		)
Total expenses	(8		)	(270		)	—			(3,427		)	—			(3,705		)
OPERATING (LOSS) INCOME	(8		)	(269		)	—			52			—			(225		)
Other income (expense), net	2			(4		)	1			17			—			16
Income from Group undertakings	—			436			79			111			(626		)	—
Expenses due to Group undertakings	—			(185		)	(27		)	(414		)	626			—
Interest expense	(43		)	(69		)	(8		)	(8		)	—			(128		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(49		)	(91		)	45			(242		)	—			(337		)
Income taxes	—			76			(11		)	(166		)	—			(101		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(49		)	(15		)	34			(408		)	—			(438		)
Interest in earnings of associates, net of tax	—			8			—			(3		)	—			5
Equity account for subsidiaries	(397		)	(390		)	(461		)	—			1,248			—
NET LOSS	(446		)	(397		)	(427		)	(411		)	1,248			(433		)
Less: Net income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
NET LOSS ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	(446	)	$	(397	)	$	(427	)	$	(424	)	$	1,248		$	(446	)
Condensed Consolidating Statement of Operations
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	8		$	—		$	3,625		$	—		$	3,633
Investment income	—			—			—			15			—			15
Other income	—			—			—			7			—			7
Total revenues	—			8			—			3,647			—			3,655
EXPENSES
Salaries and benefits	(1		)	(103		)	—			(2,103		)	—			(2,207		)
Other operating expenses	(5		)	(231		)	(1		)	(399		)	—			(636		)
Depreciation expense	—			(23		)	—			(71		)	—			(94		)
Amortization of intangible assets	—			—			—			(55		)	—			(55		)
Total expenses	(6		)	(357		)	(1		)	(2,628		)	—			(2,992		)
OPERATING (LOSS) INCOME	(6		)	(349		)	(1		)	1,019			—			663
Other income (expense), net	5			(4		)	—			31			(10		)	22
Income from Group undertakings	—			491			68			86			(645		)	—
Expenses due to Group undertakings	(10		)	(153		)	(26		)	(456		)	645			—
Loss on extinguishment of debt	—			(60		)	—			—			—			(60		)
Interest expense	(42		)	(61		)	(18		)	(5		)	—			(126		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(136		)	23			675			(10		)	499
Income taxes	—			29			(6		)	(145		)	—			(122		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(53		)	(107		)	17			530			(10		)	377
Interest in earnings of associates, net of tax	—			9			—			(9		)	—			—
Equity account for subsidiaries	418			515			344			—			(1,277		)	—
NET INCOME	365			417			361			521			(1,287		)	377
Less: Net income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	365		$	417		$	361		$	509		$	(1,287	)	$	365
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REVENUES
Commissions and fees	$	—		$	8		$	—		$	3,759		$	—		$	3,767
Investment income	—			—			—			16			—			16
Other income	—			—			—			19			—			19
Total revenues	—			8			—			3,794			—			3,802
EXPENSES
Salaries and benefits	(1		)	(81		)	—			(2,232		)	—			(2,314		)
Other operating expenses	(16		)	(133		)	—			(510		)	—			(659		)
Depreciation expense	—			(21		)	—			(71		)	—			(92		)
Amortization of intangible assets	—			—			—			(54		)	—			(54		)
Restructuring expenses	—			(14		)	—			(22		)	—			(36		)
Total expenses	(17		)	(249		)	—			(2,889		)	—			(3,155		)
OPERATING (LOSS) INCOME	(17		)	(241		)	—			905			—			647
Other (expense) income, net	(15		)	(220		)	—			11			230			6
Income from Group undertakings	—			450			91			102			(643		)	—
Expenses due to Group undertakings	—			(190		)	(29		)	(424		)	643			—
Interest expense	(43		)	(44		)	(36		)	(12		)	—			(135		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(245		)	26			582			230			518
Income taxes	—			54			(5		)	(208		)	—			(159		)
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES	(75		)	(191		)	21			374			230			359
Interest in earnings of associates, net of tax	—			10			—			4			—			14
Equity account for subsidiaries	437			609			314			—			(1,360		)	—
NET INCOME	362			428			335			378			(1,130		)	373
Less: Net income attributable to noncontrolling interests	—			—			—			(11		)	—			(11		)
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	$	362		$	428		$	335		$	367		$	(1,130	)	$	362
Condensed Statement of Comprehensive Income [Table Text Block]	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	Comprehensive (loss) income	$	(11	)	$	69		$	(110	)	$	49		$	(3	)	$	(6	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(5		)	—			(5		)
	Comprehensive (loss) income attributable to Willis Group Holdings	$	(11	)	$	69		$	(110	)	$	44		$	(3	)	$	(11	)
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2012
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	Comprehensive loss	$	(552	)	$	(494	)	$	(263	)	$	(519	)	$	1,289		$	(539	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
	Comprehensive loss attributable to Willis Group Holdings	$	(552	)	$	(494	)	$	(263	)	$	(532	)	$	1,289		$	(552	)
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2013
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	Comprehensive income	$	522		$	565		$	74		$	636		$	(1,263	)	$	534
	Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
	Comprehensive income attributable to Willis Group Holdings	$	522		$	565		$	74		$	624		$	(1,263	)	$	522
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2014
		Willis			The Guarantors			Other			Consolidating			Consolidated
		Group									adjustments
		Holdings—the Parent Issuer
		(millions)
	Comprehensive (loss) income	$	(11	)	$	69		$	49		$	(113	)	$	(6	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			(5		)	—			(5		)
	Comprehensive (loss) income attributable to Willis Group Holdings	$	(11	)	$	69		$	44		$	(113	)	$	(11	)
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2012
		Willis			The Guarantors			Other			Consolidating			Consolidated
		Group									adjustments
		Holdings—the Parent Issuer
		(millions)
	Comprehensive loss	$	(552	)	$	(494	)	$	(519	)	$	1,026		$	(539	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			(13		)	—			(13		)
	Comprehensive loss attributable to Willis Group Holdings	$	(552	)	$	(494	)	$	(532	)	$	1,026		$	(552	)
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2013
		Willis			The Guarantors			Other			Consolidating			Consolidated
		Group									adjustments
		Holdings—the Parent Issuer
		(millions)
	Comprehensive income	$	522		$	565		$	636		$	(1,189	)	$	534
	Less: Comprehensive income attributable to noncontrolling interests	—			—			(12		)	—			(12		)
	Comprehensive income attributable to Willis Group Holdings	$	522		$	565		$	624		$	(1,189	)	$	522
	Condensed Consolidating Statement of Comprehensive Income
		Year Ended December 31, 2012
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	Comprehensive loss	$	(552	)	$	(494	)	$	(528	)	$	(519	)	$	1,554		$	(539	)
	Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(13		)	—			(13		)
	Comprehensive loss attributable to Willis Group Holdings	$	(552	)	$	(494	)	$	(528	)	$	(532	)	$	1,554		$	(552	)
	Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
Comprehensive (loss) income	$	(11	)	$	69		$	(5	)	$	49		$	(108	)	$	(6	)
Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(5		)	—			(5		)
Comprehensive (loss) income attributable to Willis Group Holdings	$	(11	)	$	69		$	(5	)	$	44		$	(108	)	$	(11	)
Condensed Consolidating Statement of Comprehensive Income
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
Comprehensive income	$	522		$	565		$	504		$	636		$	(1,693	)	$	534
Less: Comprehensive income attributable to noncontrolling interests	—			—			—			(12		)	—			(12		)
Comprehensive income attributable to Willis Group Holdings	$	522		$	565		$	504		$	624		$	(1,693	)	$	522
Condensed Balance Sheet [Table Text Block]	Condensed Consolidating Balance Sheet
		As at December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	ASSETS
	CURRENT ASSETS
	Cash and cash equivalents	$	9		$	2		$	—		$	624		$	—		$	635
	Accounts receivable, net	—			—			4			1,040			—			1,044
	Fiduciary assets	—			—			—			8,948			—			8,948
	Deferred tax assets	—			—			—			12			—			12
	Other current assets	1			27			10			205			(29		)	214
	Amounts due from Group undertakings	3,674			924			1,057			1,114			(6,769		)	—
	Total current assets	3,684			953			1,071			11,943			(6,798		)	10,853
	NON-CURRENT ASSETS
	Investments in subsidiaries	—			2,536			721			—			(3,257		)	—
	Fixed assets, net	—			20			42			421			—			483
	Goodwill	—			—			—			2,937			—			2,937
	Other intangible assets, net	—			—			—			450			—			450
	Investments in associates	—			147			—			22			—			169
	Deferred tax assets	—			—			—			9			—			9
	Pension benefits asset	—			—			—			314			—			314
	Other non-current assets	3			8			2			207			—			220
	Non-current amounts due from Group undertakings	—			518			740			—			(1,258		)	—
	Total non-current assets	3			3,229			1,505			4,360			(4,515		)	4,582
	TOTAL ASSETS	$	3,687		$	4,182		$	2,576		$	16,303		$	(11,313	)	$	15,435
	LIABILITIES AND STOCKHOLDERS’ EQUITY
	CURRENT LIABILITIES
	Fiduciary liabilities	$	—		$	—		$	—		$	8,948		$	—		$	8,948
	Deferred revenue and accrued expenses	1			4			30			584			—			619
	Income taxes payable	—			—			7			55			(29		)	33
	Short-term debt and current portion of long-term debt	—			17			149			1			—			167
	Deferred tax liabilities	—			—			—			21			—			21
	Other current liabilities	67			11			46			320			—			444
	Amounts due to Group undertakings	—			4,374			1,499			896			(6,769		)	—
	Total current liabilities	68			4,406			1,731			10,825			(6,798		)	10,232
	NON-CURRENT LIABILITIES
	Investments in subsidiaries	838			—			—			—			(838		)	—
	Long-term debt	796			765			581			—			—			2,142
	Liabilities for pension benefits	—			—			—			284			—			284
	Deferred tax liabilities	—			—			—			128			—			128
	Provisions for liabilities	—			—			—			194			—			194
	Other non-current liabilities	—			—			17			372			—			389
	Non-current amounts due to Group undertakings	—			—			518			740			(1,258		)	—
	Total non-current liabilities	1,634			765			1,116			1,718			(2,096		)	3,137
	TOTAL LIABILITIES	$	1,702		$	5,171		$	2,847		$	12,543		$	(8,894	)	$	13,369
	Condensed Consolidating Balance Sheet
		As at December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	REDEEMABLE NONCONTROLLING INTEREST	—			—			—			59			—			59
	EQUITY
	Total Willis Group Holdings stockholders’ equity	1,985			(989		)	(271		)	3,679			(2,419		)	1,985
	Noncontrolling interests	—			—			—			22			—			22
	Total equity	1,985			(989		)	(271		)	3,701			(2,419		)	2,007
	TOTAL LIABILITIES AND EQUITY	$	3,687		$	4,182		$	2,576		$	16,303		$	(11,313	)	$	15,435
	Condensed Consolidating Balance Sheet
		As at December 31, 2013
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	3		$	3		$	—		$	790		$	—		$	796
Accounts receivable, net	—			—			4			1,037			—			1,041
Fiduciary assets	—			—			—			8,412			—			8,412
Deferred tax assets	—			—			—			16			(1		)	15
Other current assets	1			21			10			186			(21		)	197
Amounts due by group undertakings	4,051			903			1,317			1,484			(7,755		)	—
Total current assets	4,055			927			1,331			11,925			(7,777		)	10,461
NON-CURRENT ASSETS
Investments in subsidiaries	—			2,838			1,021			—			(3,859		)	—
Fixed assets, net	—			15			51			415			—			481
Goodwill	—			—			—			2,838			—			2,838
Other intangible assets, net	—			—			—			353			—			353
Investments in associates	—			156			—			20			—			176
Deferred tax assets	—			—			—			7			—			7
Pension benefits asset	—			—			—			278			—			278
Other non-current assets	4			9			5			188			—			206
Non-current amounts due by group undertakings	—			518			690			—			(1,208		)	—
Total non-current assets	4			3,536			1,767			4,099			(5,067		)	4,339
TOTAL ASSETS	$	4,059		$	4,463		$	3,098		$	16,024		$	(12,844	)	$	14,800
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,412		$	—		$	8,412
Deferred revenue and accrued expenses	2			1			28			555			—			586
Income taxes payable	—			3			—			39			(21		)	21
Short-term debt and current portion of long-term debt	—			15			—			—			—			15
Deferred tax liabilities	—			—			—			25			—			25
Other current liabilities	62			15			38			300			—			415
Amounts due to group undertakings	—			4,760			1,662			1,333			(7,755		)	—
Total current liabilities	64			4,794			1,728			10,664			(7,776		)	9,474
NON-CURRENT LIABILITIES
Investments in subsidiaries	985			—			—			—			(985		)	—
Long-term debt	795			782			733			1			—			2,311
Liabilities for pension benefits	—			—			—			136			—			136
Deferred tax liabilities	—			1			—			55			—			56
Provisions for liabilities	—			—			—			206			—			206
Other non-current liabilities	—			—			48			326			—			374
Non-current amounts due to group undertakings	—			—			518			690			(1,208		)	—
Total non-current liabilities	1,780			783			1,299			1,414			(2,193		)	3,083
TOTAL LIABILITIES	$	1,844		$	5,577		$	3,027		$	12,078		$	(9,969	)	$	12,557
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
EQUITY
Total Willis Group Holdings stockholders’ equity	2,215			(1,114		)	71			3,918			(2,875		)	2,215
Noncontrolling interests	—			—			—			28			—			28
Total equity	2,215			(1,114		)	71			3,946			(2,875		)	2,243
TOTAL LIABILITIES AND EQUITY	$	4,059		$	4,463		$	3,098		$	16,024		$	(12,844	)	$	14,800
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	9		$	2		$	624		$	—		$	635
Accounts receivable, net	—			4			1,040			—			1,044
Fiduciary assets	—			—			8,948			—			8,948
Deferred tax assets	—			—			12			—			12
Other current assets	1			37			205			(29		)	214
Amounts due from group undertakings	3,674			731			1,114			(5,519		)	—
Total current assets	3,684			774			11,943			(5,548		)	10,853
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,528			—			(3,528		)	—
Fixed assets, net	—			62			421			—			483
Goodwill	—			—			2,937			—			2,937
Other intangible assets, net	—			—			450			—			450
Investments in associates	—			147			22			—			169
Deferred tax assets	—			—			9			—			9
Pension benefits asset	—			—			314			—			314
Other non-current assets	3			10			207			—			220
Non-current amounts due from group undertakings	—			740			—			(740		)	—
Total non-current assets	3			4,487			4,360			(4,268		)	4,582
TOTAL ASSETS	$	3,687		$	5,261		$	16,303		$	(9,816	)	$	15,435
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	8,948		$	—		$	8,948
Deferred revenue and accrued expenses	1			34			584			—			619
Income taxes payable	—			7			55			(29		)	33
Short-term debt and current portion on long-term debt	—			166			1			—			167
Deferred tax liabilities	—			—			21			—			21
Other current liabilities	67			57			320			—			444
Amounts due to group undertakings	—			4,623			896			(5,519		)	—
Total current liabilities	68			4,887			10,825			(5,548		)	10,232
NON-CURRENT LIABILITIES
Investments in subsidiaries	838			—			—			(838		)	—
Long-term debt	796			1,346			—			—			2,142
Liabilities for pension benefits	—			—			284			—			284
Deferred tax liabilities	—			—			128			—			128
Provisions for liabilities	—			—			194			—			194
Other non-current liabilities	—			17			372			—			389
Non-current amounts due to group undertakings	—			—			740			(740		)	—
Total non-current liabilities	1,634			1,363			1,718			(1,578		)	3,137
TOTAL LIABILITIES	$	1,702		$	6,250		$	12,543		$	(7,126	)	$	13,369
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
REDEEMABLE NONCONTROLLING INTEREST	—			—			59			—			59
EQUITY
Total Willis Group Holdings stockholders’ equity	1,985			(989		)	3,679			(2,690		)	1,985
Noncontrolling interests	—			—			22			—			22
Total equity	1,985			(989		)	3,701			(2,690		)	2,007
TOTAL LIABILITIES AND EQUITY	$	3,687		$	5,261		$	16,303		$	(9,816	)	$	15,435
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	3		$	3		$	790		$	—		$	796
Accounts receivable, net	—			4			1,037			—			1,041
Fiduciary assets	—			—			8,412			—			8,412
Deferred tax assets	—			—			16			(1		)	15
Other current assets	1			31			186			(21		)	197
Amounts due from group undertakings	4,051			975			1,484			(6,510		)	—
Total current assets	4,055			1,013			11,925			(6,532		)	10,461
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,788			—			(3,788		)	—
Fixed assets, net	—			66			415			—			481
Goodwill	—			—			2,838			—			2,838
Other intangible assets, net	—			—			353			—			353
Investments in associates	—			156			20			—			176
Deferred tax assets	—			—			7			—			7
Pension benefits asset	—			—			278			—			278
Other non-current assets	4			14			188			—			206
Non-current amounts due from group undertakings	—			690			—			(690		)	—
Total non-current assets	4			4,714			4,099			(4,478		)	4,339
TOTAL ASSETS	$	4,059		$	5,727		$	16,024		$	(11,010	)	$	14,800
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	8,412		$	—		$	8,412
Deferred revenue and accrued expenses	2			29			555			—			586
Income taxes payable	—			3			39			(21		)	21
Short-term debt and current portion of long-term debt	—			15			—			—			15
Deferred tax liabilities	—			—			25			—			25
Other current liabilities	62			53			300			—			415
Amounts due to group undertakings	—			5,177			1,333			(6,510		)	—
Total current liabilities	64			5,277			10,664			(6,531		)	9,474
NON-CURRENT LIABILITIES
Investments in subsidiaries	985			—			—			(985		)	—
Long-term debt	795			1,515			1			—			2,311
Liabilities for pension benefits	—			—			136			—			136
Deferred tax liabilities	—			1			55			—			56
Provisions for liabilities	—			—			206			—			206
Other non-current liabilities	—			48			326			—			374
Non-current amounts due to group undertakings	—			—			690			(690		)	—
Total non-current liabilities	1,780			1,564			1,414			(1,675		)	3,083
TOTAL LIABILITIES	$	1,844		$	6,841		$	12,078		$	(8,206	)	$	12,557
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
EQUITY
Total Willis Group Holdings stockholders’ equity	2,215			(1,114		)	3,918			(2,804		)	2,215
Noncontrolling interests	—			—			28			—			28
Total equity	2,215			(1,114		)	3,946			(2,804		)	2,243
TOTAL LIABILITIES AND EQUITY	$	4,059		$	5,727		$	16,024		$	(11,010	)	$	14,800
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	9		$	2		$	—		$	624		$	—		$	635
Accounts receivable, net	—			4			—			1,040			—			1,044
Fiduciary assets	—			—			—			8,948			—			8,948
Deferred tax assets	—			—			—			12			—			12
Other current assets	1			41			1			205			(34		)	214
Amounts due from group undertakings	3,674			1,154			797			1,114			(6,739		)	—
Total current assets	3,684			1,201			798			11,943			(6,773		)	10,853
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,478			2,578			—			(6,056		)	—
Fixed assets, net	—			62			—			421			—			483
Goodwill	—			—			—			2,937			—			2,937
Other intangible assets, net	—			—			—			450			—			450
Investments in associates	—			147			—			22			—			169
Deferred tax assets	—			—			—			9			—			9
Pension benefits asset	—			—			—			314			—			314
Other non-current assets	3			2			8			207			—			220
Non-current amounts due from group undertakings	—			740			518			—			(1,258		)	—
Total non-current assets	3			4,429			3,104			4,360			(7,314		)	4,582
TOTAL ASSETS	$	3,687		$	5,630		$	3,902		$	16,303		$	(14,087	)	$	15,435
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,948		$	—		$	8,948
Deferred revenue and accrued expenses	1			34			—			584			—			619
Income taxes payable	—			7			5			55			(34		)	33
Short-term debt and current portion of long-term debt	—			149			17			1			—			167
Deferred tax liabilities	—			—			—			21			—			21
Other current liabilities	67			46			11			320			—			444
Amounts due to group undertakings	—			5,267			576			896			(6,739		)	—
Total current liabilities	68			5,503			609			10,825			(6,773		)	10,232
NON-CURRENT LIABILITIES
Investments in subsidiaries	838			—			—			—			(838		)	—
Long-term debt	796			581			765			—			—			2,142
Liabilities for pension benefits	—			—			—			284			—			284
Deferred tax liabilities	—			—			—			128			—			128
Provisions for liabilities	—			—			—			194			—			194
Other non-current liabilities	—			17			—			372			—			389
Non-current amounts due to group undertakings	—			518			—			740			(1,258		)	—
Total non-current liabilities	1,634			1,116			765			1,718			(2,096		)	3,137
TOTAL LIABILITIES	$	1,702		$	6,619		$	1,374		$	12,543		$	(8,869	)	$	13,369
Condensed Consolidating Balance Sheet
	As at December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
REDEEMABLE NONCONTROLLING INTEREST	—			—			—			59			—			59
EQUITY
Total Willis Group Holdings stockholders’ equity	1,985			(989		)	2,528			3,679			(5,218		)	1,985
Noncontrolling interests	—			—			—			22			—			22
Total equity	1,985			(989		)	2,528			3,701			(5,218		)	2,007
TOTAL LIABILITIES AND EQUITY	$	3,687		$	5,630		$	3,902		$	16,303		$	(14,087	)	$	15,435
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
ASSETS
CURRENT ASSETS
Cash and cash equivalents	$	3		$	3		$	—		$	790		$	—		$	796
Accounts receivable, net	—			4			—			1,037			—			1,041
Fiduciary assets	—			—			—			8,412			—			8,412
Deferred tax assets	—			—			—			16			(1		)	15
Other current assets	1			36			1			186			(27		)	197
Amounts due from group undertakings	4,051			975			793			1,484			(7,303		)	—
Total current assets	4,055			1,018			794			11,925			(7,331		)	10,461
NON-CURRENT ASSETS
Investments in subsidiaries	—			3,716			2,705			—			(6,421		)	—
Fixed assets, net	—			66			—			415			—			481
Goodwill	—			—			—			2,838			—			2,838
Other intangible assets, net	—			—			—			353			—			353
Investments in associates	—			156			—			20			—			176
Deferred tax assets	—			—			—			7			—			7
Pension benefits asset	—			—			—			278			—			278
Other non-current assets	4			5			9			188			—			206
Non-current amounts due from group undertakings	—			1,113			518			—			(1,631		)	—
Total non-current assets	4			5,056			3,232			4,099			(8,052		)	4,339
TOTAL ASSETS	$	4,059		$	6,074		$	4,026		$	16,024		$	(15,383	)	$	14,800
LIABILITIES AND STOCKHOLDERS’ EQUITY
CURRENT LIABILITIES
Fiduciary liabilities	$	—		$	—		$	—		$	8,412		$	—		$	8,412
Deferred revenue and accrued expenses	2			29			—			555			—			586
Income taxes payable	—			4			5			39			(27		)	21
Short-term debt and current portion of long-term debt	—			—			15			—			—			15
Deferred tax liabilities	—			—			—			25			—			25
Other current liabilities	62			42			11			300			—			415
Amounts due to group undertakings	—			5,813			157			1,333			(7,303		)	—
Total current liabilities	64			5,888			188			10,664			(7,330		)	9,474
NON-CURRENT LIABILITIES
Investments in subsidiaries	985			—			—			—			(985		)	—
Long-term debt	795			733			782			1			—			2,311
Liabilities for pension benefits	—			—			—			136			—			136
Deferred tax liabilities	—			1			—			55			—			56
Provisions for liabilities	—			—			—			206			—			206
Other non-current liabilities	—			48			—			326			—			374
Non-current amounts due to group undertakings	—			518			423			690			(1,631		)	—
Total non-current liabilities	1,780			1,300			1,205			1,414			(2,616		)	3,083
TOTAL LIABILITIES	$	1,844		$	7,188		$	1,393		$	12,078		$	(9,946	)	$	12,557
Condensed Consolidating Balance Sheet
	As at December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
EQUITY
Total Willis Group Holdings stockholders’ equity	2,215			(1,114		)	2,633			3,918			(5,437		)	2,215
Noncontrolling interests	—			—			—			28			—			28
Total equity	2,215			(1,114		)	2,633			3,946			(5,437		)	2,243
TOTAL LIABILITIES AND EQUITY	$	4,059		$	6,074		$	4,026		$	16,024		$	(15,383	)	$	14,800
Condensed Cash Flow Statement [Table Text Block]	Condensed Consolidating Statement of Cash Flows
		Year Ended December 31, 2014
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(35	)	$	387		$	265		$	212		$	(352	)	$	477
	CASH FLOWS FROM INVESTING ACTIVITIES
	Proceeds on disposal of fixed and intangible assets	—			—			1			6			(1		)	6
	Additions to fixed assets	—			(9		)	(10		)	(95		)	1			(113		)
	Additions to intangibles assets	—			—			—			(4		)	—			(4		)
	Acquisitions of subsidiaries, net of cash acquired	—			—			—			(241		)	—			(241		)
	Payments to acquire other investments	—			—			—			(10		)	—			(10		)
	Proceeds from sale of operations, net of cash disposed	—			—			—			86			—			86
	Proceeds from intercompany investing activities	361			—			120			435			(916		)	—
	Repayments of intercompany investing activities	—			(53		)	(131		)	(46		)	230			—
	Additional investment in subsidiaries	(31		)	—			—			—			31			—
	Net cash provided by (used in) investing activities	330			(62		)	(20		)	131			(655		)	(276		)
	CASH FLOWS FROM FINANCING ACTIVITIES
	Debt issuance costs	—			—			—			(3		)	—			(3		)
	Repayments of debt	—			(15		)	—			—			—			(15		)
	Repurchase of shares	(213		)	—			—			—			—			(213		)
	Proceeds from issue of shares	134			—			—			31			(31		)	134
	Excess tax benefits from share-based payment arrangements	—			—			—			5			—			5
	Dividends paid	(210		)	—			—			(352		)	352			(210		)
	Acquisition of noncontrolling interests	—			(4		)	—			—			—			(4		)
	Dividends paid to noncontrolling interests	—			—			—			(17		)	—			(17		)
	Proceeds from intercompany financing activities	—			46			4			180			(230		)	—
	Repayments of intercompany financing activities	—			(353		)	(249		)	(314		)	916			—
	Net cash used in financing activities	(289		)	(326		)	(245		)	(470		)	1,007			(323		)
	INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	6			(1		)	—			(127		)	—			(122		)
	Effect of exchange rate changes on cash and cash equivalents	—			—			—			(39		)	—			(39		)
	CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3			3			—			790			—			796
	CASH AND CASH EQUIVALENTS, END OF YEAR	$	9		$	2		$	—		$	624		$	—		$	635
	Condensed Consolidating Statement of Cash Flows
		Year Ended December 31, 2013
		Willis			The Other			The			Other			Consolidating			Consolidated
		Group			Guarantors			Issuer						adjustments
		Holdings
								(millions)
	NET CASH PROVIDED BY OPERATING ACTIVITIES	$	4		$	125		$	7		$	662		$	(237	)	$	561
	CASH FLOWS FROM INVESTING ACTIVITIES
	Proceeds on disposal of fixed and intangible assets	—			—			3			9			—			12
	Additions to fixed assets	—			(7		)	(11		)	(94		)	—			(112		)
	Additions to intangible assets	—			—			—			(7		)	—			(7		)
	Acquisitions of subsidiaries, net of cash acquired	—			(237		)	(230		)	(30		)	467			(30		)
	Payments to acquire other investments	—			—			—			(7		)	—			(7		)
	Proceeds from sale of associates	—			—			—			4			—			4
	Proceeds from sale of operations, net of cash disposed	—			—			230			257			(467		)	20
	Proceeds from intercompany investing activities	383			211			36			60			(690		)	—
	Repayments of intercompany investing activities	(347		)	(442		)	(120		)	(780		)	1,689			—
	Net cash provided by (used in) investing activities	36			(475		)	(92		)	(588		)	999			(120		)
	CASH FLOWS FROM FINANCING ACTIVITIES
	Senior notes issued	—			522			—			—			—			522
	Debt issuance costs	—			(8		)	—			—			—			(8		)
	Repayments of debt	—			(15		)	(521		)	—			—			(536		)
	Tender premium on extinguishment of senior notes	—			—			(65		)	—			—			(65		)
	Proceeds from issue of shares	155			—			—			—			—			155
	Excess tax benefits from share-based payment arrangements	—			—			—			2			—			2
	Dividends paid	(193		)	—			(230		)	(7		)	237			(193		)
	Acquisition of noncontrolling interests	—			—			—			(4		)	—			(4		)
	Dividends paid to noncontrolling interests	—			—			—			(10		)	—			(10		)
	Proceeds from intercompany financing activities	—			321			901			467			(1,689		)	—
	Repayments of intercompany financing activities	—			(467		)	—			(223		)	690			—
Net cash (used in) provided by financing activities	(38		)	353			85			225			(762		)	(137		)
INCREASE IN CASH AND CASH EQUIVALENTS	2			3			—			299			—			304
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(8		)	—			(8		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	1			—			—			499			—			500
CASH AND CASH EQUIVALENTS, END OF YEAR	$	3		$	3		$	—		$	790		$	—		$	796
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(23	)	$	1,504		$	(44	)	$	(97	)	$	(815	)	$	525
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			—			5			—			5
Additions to fixed assets	—			(7		)	(19		)	(109		)	—			(135		)
Additions to intangible assets	—			—			—			(2		)	—			(2		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(33		)	—			(33		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from intercompany investing activities	256			216			44			1,230			(1,746		)	—
Repayments of intercompany investing activities	—			(318		)	(10		)	(81		)	409			—
Net cash provided by (used in) investing activities	256			(109		)	15			1,003			(1,337		)	(172		)
CASH FLOWS FROM FINANCING ACTIVITIES
Repayments of debt	—			(15		)	—			—			—			(15		)
Proceeds from issue of other debt	—			1			—			—			—			1
Repurchase of shares	(100		)	—			—			—			—			(100		)
Proceeds from issue of shares	53			—			—			—			—			53
Excess tax benefits from share-based payment arrangements	—			—			—			2			—			2
Dividends paid	(185		)	—			—			(815		)	815			(185		)
Proceeds from sale of noncontrolling interest	—			—			—			3			—			3
Acquisition of noncontrolling interests	—			—			—			(39		)	—			(39		)
Dividends paid to noncontrolling interests	—			—			—			(11		)	—			(11		)
Cash received on intercompany financing activities	—			81			—			328			(409		)	—
Cash paid on intercompany financing activities	—			(1,462		)	(134		)	(150		)	1,746			—
Net cash used in financing activities	(232		)	(1,395		)	(134		)	(682		)	2,152			(291		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1			—			(163		)	224			—			62
Effect of exchange rate changes on cash and cash equivalents	—			—			—			2			—			2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	—			—			163			273			—			436
CASH AND CASH EQUIVALENTS, END OF YEAR	$	1		$	—		$	—		$	499		$	—		$	500
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2014
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(35	)	$	652		$	212		$	(352	)	$	477
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			1			6			(1		)	6
Additions to fixed assets	—			(19		)	(95		)	1			(113		)
Additions to intangibles assets	—			—			(4		)	—			(4		)
Acquisitions of subsidiaries, net of cash acquired	—			—			(241		)	—			(241		)
Payments to acquire other investments	—			—			(10		)	—			(10		)
Proceeds from disposal of operations, net of cash disposed	—			—			86			—			86
Proceeds from intercompany investing activities	361			120			435			(916		)	—
Repayments of intercompany investing activities	—			(180		)	(46		)	226			—
Additional investment in subsidiaries	(31		)	—			—			31			—
Net cash provided by (used in) investing activities	330			(78		)	131			(659		)	(276		)
CASH FLOWS FROM FINANCING ACTIVITIES
Debt issuance costs	—			—			(3		)	—			(3		)
Repayments of debt	—			(15		)	—			—			(15		)
Repurchase of shares	(213		)	—			—			—			(213		)
Proceeds from the issue of shares	134			—			31			(31		)	134
Excess tax benefits from share-based payment arrangements	—			—			5			—			5
Dividends paid	(210		)	—			(352		)	352			(210		)
Acquisition of noncontrolling interests	—			(4		)	—			—			(4		)
Dividends paid to noncontrolling interests	—			—			(17		)	—			(17		)
Proceeds from intercompany financing activities	—			46			180			(226		)	—
Repayments of intercompany financing activities	—			(602		)	(314		)	916			—
Net cash used in financing activities	(289		)	(575		)	(470		)	1,011			(323		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	6			(1		)	(127		)	—			(122		)
Effect of exchange rate changes on cash and cash equivalents	—			—			(39		)	—			(39		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3			3			790			—			796
CASH AND CASH EQUIVALENTS, END OF YEAR	$	9		$	2		$	624		$	—		$	635
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2013
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
NET CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES	$	4		$	(98	)	$	662		$	(7	)	$	561
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			3			9			—			12
Additions to fixed assets	—			(18		)	(94		)	—			(112		)
Additions to intangible assets	—			—			(7		)	—			(7		)
Acquisitions of subsidiaries, net of cash acquired	—			(237		)	(30		)	237			(30		)
Payments to acquire other investments	—			—			(7		)	—			(7		)
Proceeds from sale of associates	—			—			4			—			4
Proceeds from sale of operations, net of cash disposed	—			—			257			(237		)	20
Proceeds from intercompany investing activities	383			223			60			(666		)	—
Repayments of intercompany investing activities	(347		)	(120		)	(780		)	1,247			—
Net cash provided by (used in) investing activities	36			(149		)	(588		)	581			(120		)
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued	—			522			—			—			522
Debt issuance costs	—			(8		)	—			—			(8		)
Repayments of debt	—			(536		)	—			—			(536		)
Tender premium on extinguishment of senior notes	—			(65		)	—			—			(65		)
Proceeds from the issue of shares	155			—			—			—			155
Excess tax benefits from share-based payment arrangements	—			—			2			—			2
Dividends paid	(193		)	—			(7		)	7			(193		)
Acquisition of noncontrolling interests	—			—			(4		)	—			(4		)
Dividends paid to noncontrolling interests	—			—			(10		)	—			(10		)
Proceeds from intercompany financing activities	—			780			467			(1,247		)	—
Repayments of intercompany financing activities	—			(443		)	(223		)	666			—
Net cash (used in) provided by financing activities	(38		)	250			225			(574		)	(137		)
INCREASE IN CASH AND CASH EQUIVALENTS	2			3			299			—			304
Effect of exchange rate changes on cash and cash equivalents	—			—			(8		)	—			(8		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	1			—			499			—			500
CASH AND CASH EQUIVALENTS, END OF YEAR	$	3		$	3		$	790		$	—		$	796
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2012
	Willis			The			Other			Consolidating			Consolidated
	Group			Guarantors						adjustments
	Holdings —
	the Parent
	Issuer
	(millions)
NET CASH (USED IN) PROVIDED BY OPERATING	$	(23	)	$	1,460		$	(97	)	$	(815	)	$	525
ACTIVITIES
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			5			—			5
Additions to fixed assets	—			(26		)	(109		)	—			(135		)
Additions to intangible assets	—			—			(2		)	—			(2		)
Acquisitions of subsidiaries, net of cash acquired	—			—			(33		)	—			(33		)
Payments to acquire other investments	—			—			(7		)	—			(7		)
Proceeds from intercompany investing activities	256			150			1,230			(1,636		)	—
Repayments of intercompany investing activities	—			(328		)	(81		)	409			—
Net cash provided by (used in) investing activities	256			(204		)	1,003			(1,227		)	(172		)
CASH FLOWS FROM FINANCING ACTIVITIES
Repayments of debt	—			(15		)	—			—			(15		)
Proceeds from the issue of other debt	—			1			—			—			1
Repurchase of shares	(100		)	—			—			—			(100		)
Proceeds from issue of shares	53			—			—			—			53
Excess tax benefits from share-based payment arrangements	—			—			2			—			2
Dividends paid	(185		)	—			(815		)	815			(185		)
Proceeds from sale of noncontrolling interest	—			—			3			—			3
Acquisition of noncontrolling interests	—			—			(39		)	—			(39		)
Dividends paid to noncontrolling interests	—			—			(11		)	—			(11		)
Proceeds from intercompany financing activities	—			81			328			(409		)	—
Repayments of intercompany financing activities	—			(1,486		)	(150		)	1,636			—
Net cash used in financing activities	(232		)	(1,419		)	(682		)	2,042			(291		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1			(163		)	224			—			62
Effect of exchange rate changes on cash and cash equivalents	—			—			2			—			2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	—			163			273			—			436
CASH AND CASH EQUIVALENTS, END OF YEAR	$	1		$	—		$	499		$	—		$	500
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2014
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(35	)	$	781		$	181		$	212		$	(662	)	$	477
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			1			—			6			(1		)	6
Additions to fixed assets	—			(19		)	—			(95		)	1			(113		)
Additions to intangible assets	—			—			—			(4		)	—			(4		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(241		)	—			(241		)
Payments to acquire other investments	—			—			—			(10		)	—			(10		)
Proceeds from sale of operations, net of cash disposed	—			—			—			86			—			86
Proceeds from intercompany investing activities	361			120			—			435			(916		)	—
Repayments of intercompany investing activities	—			(180		)	(4		)	(46		)	230			—
Additional investment in subsidiaries	(31		)	—			—			—			31			—
Net cash provided by (used in) investing activities	330			(78		)	(4		)	131			(655		)	(276		)
CASH FLOWS FROM FINANCING ACTIVITIES
Debt issuance costs	—			—			—			(3		)	—			(3		)
Repayments of debt	—			—			(15		)	—			—			(15		)
Repurchase of shares	(213		)	—			—			—			—			(213		)
Proceeds from issue of shares	134			—			—			31			(31		)	134
Excess tax benefits from share-based payment arrangement	—			—			—			5			—			5
Dividends paid	(210		)	(155		)	(155		)	(352		)	662			(210		)
Acquisition of noncontrolling interests	—			(4		)	—			—			—			(4		)
Dividends paid to noncontrolling interests	—			—			—			(17		)	—			(17		)
Proceeds from intercompany financing activities	—			50			—			180			(230		)	—
Repayments of intercompany financing activities	—			(595		)	(7		)	(314		)	916			—
Net cash used in financing activities	(289		)	(704		)	(177		)	(470		)	1,317			(323		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	6			(1		)	—			(127		)	—			(122		)
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(39		)	—			(39		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3			3			—			790			—			796
CASH AND CASH EQUIVALENTS, END OF YEAR	$	9		$	2		$	—		$	624		$	—		$	635
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2013
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH PROVIDED BY OPERATING ACTIVITIES	$	4		$	399		$	63		$	662		$	(567	)	$	561
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			3			—			9			—			12
Additions to fixed assets	—			(18		)	—			(94		)	—			(112		)
Additions to intangible assets	—			—			—			(7		)	—			(7		)
Acquisitions of subsidiaries, net of cash acquired	—			(237		)	—			(30		)	237			(30		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from sale of associates	—			—			—			4			—			4
Proceeds from sale of operations, net of cash disposed	—			—			—			257			(237		)	20
Proceeds from intercompany investing activities	383			160			132			60			(735		)	—
Repayments of intercompany investing activities	(347		)	(120		)	(442		)	(780		)	1,689			—
Net cash provided by (used in) investing activities	36			(212		)	(310		)	(588		)	954			(120		)
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued	—			—			522			—			—			522
Debt issuance costs	—			—			(8		)	—			—			(8		)
Repayments of debt	—			(521		)	(15		)	—			—			(536		)
Tender premium on extinguishment of senior notes	—			(65		)	—			—			—			(65		)
Proceeds from issue of shares	155			—			—			—			—			155
Excess tax benefits from share-based payment arrangement	—			—			—			2			—			2
Dividends paid	(193		)	(230		)	(330		)	(7		)	567			(193		)
Acquisition of noncontrolling interests	—			—			—			(4		)	—			(4		)
Dividends paid to noncontrolling interests	—			—			—			(10		)	—			(10		)
Proceeds from intercompany financing activities	—			1,075			147			467			(1,689		)	—
Repayments of intercompany financing activities	—			(443		)	(69		)	(223		)	735			—
Net cash (used in) provided by financing activities	(38		)	(184		)	247			225			(387		)	(137		)
INCREASE IN CASH AND CASH EQUIVALENTS	2			3			—			299			—			304
Effect of exchange rate changes on cash and cash equivalents	—			—			—			(8		)	—			(8		)
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	1			—			—			499			—			500
CASH AND CASH EQUIVALENTS, END OF YEAR	$	3		$	3		$	—		$	790		$	—		$	796
Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2012
	Willis			The Other			The			Other			Consolidating			Consolidated
	Group			Guarantors			Issuer						adjustments
	Holdings
							(millions)
NET CASH (USED IN) PROVIDED BY OPERATING ACTIVITIES	$	(23	)	$	2,393		$	1,356		$	(97	)	$	(3,104	)	$	525
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets	—			—			—			5			—			5
Additions to fixed assets	—			(26		)	—			(109		)	—			(135		)
Additions to intangible assets	—			—			—			(2		)	—			(2		)
Acquisitions of subsidiaries, net of cash acquired	—			—			—			(33		)	—			(33		)
Payments to acquire other investments	—			—			—			(7		)	—			(7		)
Proceeds from intercompany investing activities	256			176			78			1,230			(1,740		)	—
Repayments of intercompany investing activities	—			(197		)	(131		)	(81		)	409			—
Net cash provided by (used in) investing activities	256			(47		)	(53		)	1,003			(1,331		)	(172		)
CASH FLOWS FROM FINANCING ACTIVITIES
Repayments of debt	—			(4		)	(11		)	—			—			(15		)
Proceeds from issue of other debt	—			—			1			—			—			1
Repurchase of shares	(100		)	—			—			—			—			(100		)
Proceeds from issue of shares	53			—			—			—			—			53
Excess tax benefits from share-based payment arrangements	—			—			—			2			—			2
Dividends paid	(185		)	(1,220		)	(1,069		)	(815		)	3,104			(185		)
Proceeds from sale of noncontrolling interests	—			—			—			3			—			3
Acquisition of noncontrolling interests	—			—			—			(39		)	—			(39		)
Dividends paid to noncontrolling interests	—			—			—			(11		)	—			(11		)
Proceeds from intercompany financing activities	—			81			—			328			(409		)	—
Repayments of intercompany financing activities	—			(1,366		)	(224		)	(150		)	1,740			—
Net cash used in financing activities	(232		)	(2,509		)	(1,303		)	(682		)	4,435			(291		)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1			(163		)	—			224			—			62
Effect of exchange rate changes on cash and cash equivalents	—			—			—			2			—			2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	—			163			—			273			—			436
CASH AND CASH EQUIVALENTS, END OF YEAR	$	1		$	—		$	—		$	499		$	—		$	500

Quarterly_Financial_Data_Unaud1

Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Quarterly financial data
		Three Months Ended
		March 31,			June 30,			September 30,			December 31,
		(millions, except per share data)
	2014
	Total revenues	$	1,097		$	935		$	812		$	958
	Total expenses	(771		)	(787		)	(778		)	(819		)
	Net income (loss)	250			48			(8		)	83
	Net income (loss) attributable to Willis Group Holdings	246			47			(7		)	76
	Earnings per share
	— Basic	$	1.37		$	0.26		$	(0.04	)	$	0.43
	— Diluted	$	1.35		$	0.26		$	(0.04	)	$	0.42
	2013
	Total revenues	$	1,051		$	890		$	795		$	919
	Total expenses	(770		)	(723		)	(725		)	(774		)
	Net income (loss)	223			107			(27		)	74
	Net income (loss) attributable to Willis Group Holdings	219			105			(27		)	68
	Earnings per share
	— Basic	$	1.27		$	0.6		$	(0.15	)	$	0.38
	— Diluted	$	1.24		$	0.59		$	(0.15	)	$	0.37

Basis_of_Presentation_and_Sign3

Basis of Presentation and Significant Accounting Policies (Details Textual) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2014
Goodwill [Line Items]
Offset between deferred tax assets and uncertain tax positions				$21
Depreciation on Buildings and Long Leaseholds, Term	50 years
Threshold for Amortization of Gain Loss on Defined Benefit Plan, Percent	10.00%
Basis of presentation and significant accounting policies (Textual) [Abstract]
Depreciation on buildings and long leaseholds	calculated over the lesser of 50 years or the lease term.
Depreciation on furniture and equipment	calculated based on a range of 3 to 10 years.
Goodwill impairment charge	$0	$0	($492)
Equity ownership	Company has an equity ownership in the voting stock of the investee between 20 and 50 percent
Tax benefit	greater than 50 percent likely to be realized on settlement with the tax authority, assuming full knowledge of the position and all relevant facts.
Minimum [Member]
Goodwill [Line Items]
Depreciation on Furniture and Equipment, Term	3 years
Maximum [Member]
Goodwill [Line Items]
Depreciation on Furniture and Equipment, Term	10 years
Acquired client relationships | Minimum [Member]
Goodwill [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Acquired client relationships | Maximum [Member]
Goodwill [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years
Non-compete Agreements
Goodwill [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years
Acquired trade names | Minimum [Member]
Goodwill [Line Items]
Finite-Lived Intangible Asset, Useful Life	3 years
Acquired trade names | Maximum [Member]
Goodwill [Line Items]
Finite-Lived Intangible Asset, Useful Life	4 years
Acquired other intangible assets
Goodwill [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years

Basis_of_Presentation_and_Sign4

Basis of Presentation and Significant Accounting Policies Offset between deferred tax assets and uncertain tax positions (Details) (USD $)	Mar. 31, 2014
In Millions, unless otherwise specified
Offset between deferred tax assets and uncertain tax positions [Abstract]
Offset between deferred tax assets and uncertain tax positions	$21

Basis_of_Presentation_and_Sign5

Basis of Presentation and Significant Accounting Policies Associate loan (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Debt Disclosure [Abstract]
Interest Bearing Vendor Loans by Company	$41	$46
Convertible Bonds Issued by Company	$106	$110

Employees_Details_1

Employees (Details 1) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
	Person	Person	Person
Document Fiscal Year Focus	2014
Entity Number of Employees	18,200	17,900	17,500
Salaries and benefits expense
Salaries and other compensation awards	$2,069	$1,953	$2,258
Share-based Compensation	52	42	32
Severance costs	8	32	6
Social security costs	147	135	133
Retirement benefits — defined benefit plan (income) expense	-17	-4	2
Retirement benefits — defined contribution plan expense	55	49	44
Total salaries benefit expense	2,314	2,207	2,475
Amortization and write-off of cash retention awards	$10	$6	$416

Employees_Details_Textual

Employees (Details Textual) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
		Person
Write off of unamortized cash retention awards	$0	$0	$200
Severance cost arising in normal course of business	8	32	6
Operational Review		29
Operational Review Severance Costs		28
Operational Review Average Number Of Positions Eliminated		207
Operating Expense [Member]
Severance cost arising in normal course of business	$8	$4	$6

ShareBased_Compensation_Detail

Share-Based Compensation (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Option valuation assumptions
Expected volatility	18.70%	24.70%	32.10%
Expected dividends	2.80%	2.60%	3.20%
Expected life (years)	4 years	4 years	5 years
Risk-free interest rate	1.30%	1.50%	0.90%

ShareBased_Compensation_Detail1

Share-Based Compensation (Details 1) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2012
Summary of restricted stock unit activity under share based compensation plans
Shares, Balance beginning of year	2,929,000
Weighted Average Grant Date Fair Value, Balance beginning of year	$38.71
Shares, Granted	1,750,000
Weighted Average Grant Date Fair Value, Granted	$43.03
Shares, Vested	-858,000
Weighted Average Grant Date Fair Value, Vested	$37.19
Shares, Forfeited	-327,000
Weighted Average Grant Date Fair Value, Forfeited	$37.62
Shares, Balance end of year	3,494,000
Weighted Average Grant Date Fair Value, Balance end of year	$41.35
Time Based Stock Options [Member]
Summary of option activity under share based compensation plans
Shares, Balance beginning of year	7,983,000		10,200,000
Weighted Average Exercise Price, Balance beginning of year	$35.95	[1]
Options, Granted	1,069,000
Weighted Average Exercise Price, Granted	$41	[1]
Options, Exercised	-2,795,000
Weighted Average Exercise Price, Exercised	$34.65	[1]
Options, Forfeited	-362,000
Weighted Average Exercise Price, Forfeited	$37.31	[1]
Options, Expired	-212,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period, Weighted Average Exercise Price	$36.05	[1]
Shares, Balance end of year	5,683,000		10,200,000
Weighted Average Exercise Price, Balance end of year	$37.45	[1]
Weighted Average Remaining Contractual Term, end of year	5 years
Aggregate Intrinsic Value, end of year	$42
Options vested or expected to vest at December 31, 2011	5,131,000
Weighted Average Exercise Price, Options vested or expected to vest at December 31,2011	$37.41	[1]
Weighted Average Remaining Contractual Term, Options vested or expected to vest at December 31,2011	5 years
Aggregate Intrinsic Value, Options vested or expected to vest at December 31,2011	38
Options exercisable at December 31, 2011	2,712,000
Weighted Average Exercise Price, Options exercisable at December 31,2011	$35.84	[1]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term	4 years
Aggregate Intrinsic Value, Options Exercisable at December 31,2011	24
Performance Based Stock Options [Member]
Summary of option activity under share based compensation plans
Shares, Balance beginning of year	5,260,000		6,500,000
Weighted Average Exercise Price, Balance beginning of year	$32.80	[1]
Options, Exercised	-1,201,000
Weighted Average Exercise Price, Exercised	$29.46	[1]
Options, Forfeited	-392,000
Weighted Average Exercise Price, Forfeited	$33.86	[1]
Shares, Balance end of year	3,667,000		6,500,000
Weighted Average Exercise Price, Balance end of year	$33.78	[1]
Weighted Average Remaining Contractual Term, end of year	3 years
Aggregate Intrinsic Value, end of year	40
Options vested or expected to vest at December 31, 2011	3,376,000
Weighted Average Exercise Price, Options vested or expected to vest at December 31,2011	$33.64	[1]
Weighted Average Remaining Contractual Term, Options vested or expected to vest at December 31,2011	3 years
Aggregate Intrinsic Value, Options vested or expected to vest at December 31,2011	38
Options exercisable at December 31, 2011	2,829,000
Weighted Average Exercise Price, Options exercisable at December 31,2011	$32.81	[1]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term	3 years
Aggregate Intrinsic Value, Options Exercisable at December 31,2011	$34
[1]	Certain options are exercisable in pounds sterling and are converted to dollars using the exchange rate at December 31, 2014.

ShareBased_Compensation_Detail2

Share-Based Compensation (Details Textual) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock units	858,000
Share-based compensation	$52	$42	$32
Income tax benefit for share based compensation arrangements	12	9	9
Cash received from option exercises	134	155	53
Tax benefit realized from option exercises	20	28	8
2012 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant under this plan	13,776,935
Plan adoption date	April 25, 2012
Two Thousand Eight Share Purchase and Option Plan Member
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Plan adoption date	April 23, 2008
Plan expiry date	25-Apr-12
Employee Stock Purchase Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Plan expiry date	31-May-11
Two Thousand Ten North America Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Plan expiry date	31-May-20
Time Based Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant-date fair value	$5.33	$7.74	$6.98
Intrinsic value of options exercised	22	32	8
Unrecognized compensation cost related to nonvested share-based compensation	15
Weighted average period in which cost is expected to be recognized	2 years
Performance Based Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant-date fair value			$7.61
Intrinsic value of options exercised	15	14	5
Unrecognized compensation cost related to nonvested share-based compensation	2
Weighted average period in which cost is expected to be recognized	1 year
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to nonvested share-based compensation	$109
Weighted average period in which cost is expected to be recognized	2 years
Number of restricted stock units	857,603	873,670
Average share price	$44.09	$41.10

Restructuring_Costs_Details

Restructuring Costs (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 01, 2018	Dec. 31, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	$36	$0	$0
Restructuring Reserve	11	0
Payments for Restructuring	-25
Restructuring Charges	36
Contract Termination [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	16
Restructuring Reserve	5	0
Payments for Restructuring	-11
Restructuring Charges	16
Other Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	20
Restructuring Reserve	6	0
Payments for Restructuring	-14
Restructuring Charges	20
Willis North America Inc [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	3
Willis North America Inc [Member] | Contract Termination [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	3
Willis North America Inc [Member] | Other Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	0
International [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	5
International [Member] | Contract Termination [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	3
International [Member] | Other Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	2
Global [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	11
Global [Member] | Contract Termination [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	10
Global [Member] | Other Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	1
Corporate Segment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	17
Restructuring Charges	17	0	0
Corporate Segment [Member] | Contract Termination [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	0
Corporate Segment [Member] | Other Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Costs	17
Scenario, Forecast [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring & Related, Expected Savings				300	420
Restructuring and Related Cost, Expected Cost					$410

Auditors_Remuneration_Details

Auditors' Remuneration (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Analysis of auditor's remuneration
Audit of group consolidated financial statements	$5	$4	$4
Other assurance services	2	3	3
Other non-audit services	1	1	1
Total auditors’ remuneration	$8	$8	$8

Recovered_Sheet1

Other (Expense) Income Net other (expense) income net (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other Income and Expenses [Abstract]
Net gain (loss) on disposal of operations	$12	$2	($3)
Effect of Exchange Rate Changes on Net Income	-14	0	0
Foreign Currency Transaction Gain (Loss), Realized	8	20	19
Other Nonoperating Income (Expense)	$6	$22	$16

Income_Taxes_Details

Income Taxes (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income from continuing operations before income taxes and interest in earnings of associates by location of taxing jurisdiction
Income (loss) from continuing operations before income taxes and interest in earnings of associates	$518	$499	($337)
Current income taxes:
US federal tax	-16	7	3
US state and local taxes	7	3	1
UK corporation tax	29	28	2
Other jurisdictions	73	45	41
Total current taxes	93	83	47
Deferred taxes:
US federal tax	30	10	-44
US state and local taxes	10	1	-41
Effect of additional US valuation allowance	5	2	113
UK corporation tax	24	17	27
Other jurisdictions	-3	9	-1
Total deferred taxes	66	39	54
Total income tax	159	122	101
Ireland
Income from continuing operations before income taxes and interest in earnings of associates by location of taxing jurisdiction
Income (loss) from continuing operations before income taxes and interest in earnings of associates	-65	-52	-47
United States
Income from continuing operations before income taxes and interest in earnings of associates by location of taxing jurisdiction
Income (loss) from continuing operations before income taxes and interest in earnings of associates	92	-11	-615
United Kingdom
Income from continuing operations before income taxes and interest in earnings of associates by location of taxing jurisdiction
Income (loss) from continuing operations before income taxes and interest in earnings of associates	154	282	25
Other jurisdictions
Income from continuing operations before income taxes and interest in earnings of associates by location of taxing jurisdiction
Income (loss) from continuing operations before income taxes and interest in earnings of associates	$337	$280	$300

Income_Taxes_Details_1

Income Taxes (Details 1) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation between US federal income taxes at the statutory rate and the Company's provision for income taxes on continuing operations
Income (loss) from continuing operations before income taxes and interest in earnings of associates	$518	$499	($337)
US federal statutory income tax rate	35.00%	35.00%	35.00%
Income tax expense at US federal tax rate	181	175	-118
Adjustments to derive effective rate:
Non-deductible expenditure	21	19	15
Tax impact of internal restructurings	0	11	0
Movement in provision for unrecognized tax benefits	1	-1	6
Impairment of non-qualifying goodwill	0	0	137
effective income tax rate reconciliation non deductible goodwill disposal	11	0	0
Impact of change in tax rate on deferred tax balances	0	-4	-3
Adjustment in respect of prior periods	-2	1	6
Non Deductible Venezuelan foreign exchange loss	5
Effect of foreign exchange and other differences	-4	1	2
Changes in valuation allowances applied to deferred tax assets	7	0	114
Adjustments to eliminate the net tax effect of intra-group items	-30	-30	-31
Tax differentials of foreign earnings:
Foreign jurisdictions	-48	-54	-12
US state taxes and local taxes	17	4	-15
Total income tax	$159	$122	$101

Income_Taxes_Details_2

Income Taxes (Details 2) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Deferred tax assets:
Accrued expenses not currently deductible	$133	$153
US state net operating losses	76	70
UK net operating losses	1	3
Other net operating losses	12	5
UK capital losses	39	43
Accrued retirement benefits	109	47
Deferred compensation	34	37
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost	22	25
Gross deferred tax assets	426	383
Less: valuation allowance	-280	-196	-221	-102
Net deferred tax assets	146	187
Deferred tax liabilities:
Cost of intangible assets, net of related amortization	149	120
Cost of tangible assets, net of related amortization	38	44
Deferred Tax Liabilities, Prepaid Expenses	62	56
Accrued revenue not currently taxable	25	23
Financial derivative transactions	0	3
Deferred tax liabilities	274	246
Net deferred tax (liability) asset	-128	-59
Current:
Deferred tax assets	12	15
Deferred tax liabilities	-21	-25
Net current deferred tax assets	-9	-10
Non-current:
Deferred tax assets	9	7
Deferred tax liabilities	-128	-56
Net non-current deferred tax liabilities	-119	-49
Net deferred tax (liability) asset	($128)	($59)

Income_Taxes_Details_3

Income Taxes (Details 3) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Summary valuation allowances
Beginning balance	$196	$221	$102
Additions/ (releases) charged to costs and expenses	17	15	110
Other movements	67	-40	12
Foreign exchange differences	0	0	-3
Ending balance	$280	$196	$221

Income_Taxes_Details_4

Income Taxes (Details 4) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Unrecognized Tax Benefits, Increases Resulting from Current Period Tax Positions	$5	$9	$8
Unrecognized Tax Benefits, Increases Resulting from Prior Period Tax Positions	-26	0	16
Reconciliation of the beginning and ending amounts of unrecognized tax benefits
Beginning balance	41	37	16
Reductions due to a lapse of the applicable statute of limitation	0	-5	-3
Other movements	-1	0	0
Ending balance	$19	$41	$37

Income_Taxes_Details_Textual

Income Taxes (Details Textual) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating Loss Carryforwards [Line Items]
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount	$7	$0	$114
Deferred tax assets from equity compensation greater than compensation recognized for financial reporting		8
Equity adjustment for previously unrecognized deferred tax assets due to equity compensation		8
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost	22	25
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	19
Income Taxes (Additional Textual) [Abstract]
US federal statutory income tax rate	35.00%	35.00%	35.00%
Valuation allowances to reduce deferred tax assets to estimated realizable value	280	196	221	102
Deferred tax assets net of valuation allowance	146	187
Unrecognized Tax Benefits	19	41	37	16
Approximate tax benefits to be recognized relating to release of provisions no longer required	1
Deferred Tax Assets, Operating Loss Carryforwards, State and Local	76	70
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration	76
Deferred Tax Assets Operating Loss Carryforwards Subject To Expiration 2015 to 2018	8
Deferred Tax Assets Operating Loss Carryforwards Subject To Expiration 2019 to 2023	17
Deferred Tax Assets Operating Loss Carryforwards Subject To Expiration 2024 to 2034	51
Ireland
Income Taxes (Additional Textual) [Abstract]
Ireland federal statutory income tax rate	25.00%
United Kingdom
Income Taxes (Additional Textual) [Abstract]
Valuation allowances relating to deferred tax assets arising from UK other net operating losses	10
Valuation allowances relating to deferred tax assets arising from UK capital loss carryforwards	39
United States
Income Taxes (Additional Textual) [Abstract]
Valuation allowances to reduce deferred tax assets to estimated realizable value	$231

Earnings_Per_Share_Details

Earnings Per Share (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Basic and diluted earnings per share
Net Income (Loss) Attributable to Parent	$76	($7)	$47	$246	$68	($27)	$105	$219	$362	$365	($446)
Basic weighted average number of shares outstanding									178	176	173
Dilutive effect of potentially issuable shares									3	3	0
Diluted average number of shares outstanding									181	179	173
Basic earnings per share:
— Continuing operations	$0.43	($0.04)	$0.26	$1.37	$0.38	($0.15)	$0.60	$1.27	$2.03	$2.07	($2.58)
Dilutive effect of potentially issuable shares									($0.03)	($0.03)	$0
Net (loss) income attributable to Willis Group Holdings shareholders, Basic									$2.03	$2.07	($2.58)
Diluted Earnings per share:
— Continuing operations	$0.42	($0.04)	$0.26	$1.35	$0.37	($0.15)	$0.59	$1.24	$2	$2.04	($2.58)
Net (loss) income attributable to Willis Group Holdings shareholders, Diluted									$2	$2.04	($2.58)

Earnings_Per_Share_Details_Tex

Earnings Per Share (Details Textual)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Time Based Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share-based compensation, options outstanding	5,683,000	7,983,000	10,200,000
Performance Based Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share-based compensation, options outstanding	3,667,000	5,260,000	6,500,000
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share-based compensation, options outstanding	3,500,000	2,900,000	2,500,000
Restricted stock units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive stock options	1,500,000	1,300,000	2,500,000
Equity Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive stock options	2,400,000	2,100,000	16,700,000

Acquisitions_Details

Acquisitions (Details) (USD $)	12 Months Ended	3 Months Ended		12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2015
Business Acquisition [Line Items]
Additional consideration up to	$26			13
Goodwill	2,937			2,838	2,827
Business Acquisition, Transaction Costs	3			1
Max Matthiessen [Member]
Business Acquisition [Line Items]
Cash consideration	204
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	134
Charles Monat [Member]
Business Acquisition [Line Items]
Cash consideration		59
Additional consideration up to		29
Business Combination, Contingent Consideration, Fair Value		12
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	35
Prime Professions [Member]
Business Acquisition [Line Items]
Cash consideration			29
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles				17
Other Acquisitions [Domain]
Business Acquisition [Line Items]
Cash consideration			27
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles				16
Acquired trade names | Max Matthiessen [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	2
Acquired intangible assets, expected life	4 years
Acquired trade names | Charles Monat [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	8
Acquired intangible assets, expected life	5 years
Acquired trade names | Prime Professions [Member]
Business Acquisition [Line Items]
Acquired intangible assets, expected life				3 years
Goodwill [Member] | Max Matthiessen [Member]
Business Acquisition [Line Items]
Goodwill	139
Goodwill [Member] | Charles Monat [Member]
Business Acquisition [Line Items]
Goodwill	31
Goodwill [Member] | Prime Professions [Member]
Business Acquisition [Line Items]
Goodwill				15
Goodwill [Member] | Other Acquisitions [Domain]
Business Acquisition [Line Items]
Goodwill				14
Non-compete Agreements
Business Acquisition [Line Items]
Acquired intangible assets, expected life	5 years
Non-compete Agreements | Prime Professions [Member]
Business Acquisition [Line Items]
Acquired intangible assets, expected life				8 years
Acquired client relationships | Max Matthiessen [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	56
Acquired intangible assets, expected life	12 years
Acquired client relationships | Charles Monat [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	27
Acquired intangible assets, expected life	11 years
Acquired client relationships | Prime Professions [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles				16
Acquired intangible assets, expected life				15 years
Management contracts [Member] | Max Matthiessen [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	76
Acquired intangible assets, expected life	18 years
Contingent Consideration Type [Domain] | Scenario, Forecast [Member] | Prime Professions [Member]
Business Acquisition [Line Items]
Additional consideration up to						$2

Fixed_Assets_Net_Details

Fixed Assets, Net (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Depreciation	($92)		($94)		($79)
Analysis of fixed asset activity
Cost : Beginning Balance	949		881
Additions	116		112
Disposals	-41		-50
Foreign exchange	-44		6
Cost : Ending Balance	980		949		881
Depreciation: Beginning Balance	-468		-413
Disposals	-38		-42
Foreign exchange	25		-3
Depreciation: Ending Balance	-497		-468		-413
Net book value	481
Net book value	483		481
Land and buildings (i)
Property, Plant and Equipment [Line Items]
Depreciation	-4	[1]	-3	[1]
Analysis of fixed asset activity
Cost : Beginning Balance	89	[1]	78	[1]
Additions	7	[1]	10	[1]
Disposals	0	[1]	0	[1]
Foreign exchange	-3	[1]	1	[1]
Cost : Ending Balance	93	[1]	89	[1]
Depreciation: Beginning Balance	-36	[1]	-32	[1]
Disposals	0	[1]	0	[1]
Foreign exchange	2	[1]	-1	[1]
Depreciation: Ending Balance	-38	[1]	-36	[1]
Net book value	53	[1]
Net book value	55	[1]	53	[1]
Leasehold improvements
Property, Plant and Equipment [Line Items]
Depreciation	-20		-18
Analysis of fixed asset activity
Cost : Beginning Balance	242		227
Additions	25		22
Disposals	-12		-7
Foreign exchange	-10		0
Cost : Ending Balance	245		242
Depreciation: Beginning Balance	-87		-75
Disposals	-10		-6
Foreign exchange	4		0
Depreciation: Ending Balance	-93		-87
Net book value	155
Net book value	152		155
Furniture and equipment
Property, Plant and Equipment [Line Items]
Depreciation	-68		-73
Analysis of fixed asset activity
Cost : Beginning Balance	618		576
Additions	84		80
Disposals	-29		-43
Foreign exchange	-31		5
Cost : Ending Balance	642		618
Depreciation: Beginning Balance	-345		-306
Disposals	-28		-36
Foreign exchange	19		-2
Depreciation: Ending Balance	-366		-345
Net book value	273
Net book value	$276		$273
[1]	Included within land and buildings are assets held under capital leases: At December 31, 2014, cost and accumulated depreciation were $32 million and $8 million respectively (2013: $31 million and $6 million, respectively; 2012: $25 million and $4 million respectively). Depreciation in the year ended December 31, 2014 was $2 million (2013: $2 million; 2012: $1 million).

Fixed_Assets_Net_Details_Textu

Fixed Assets, Net (Details Textual) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fixed Assets (Textual) [Abstract]
Cost	$980	$949	$881
Accumulated depreciation	497	468	413
Depreciation expense	92	94	79
Assets Held under Capital Leases [Member]
Fixed Assets (Textual) [Abstract]
Cost	32	31	25
Accumulated depreciation	8	6	4
Depreciation, Depletion and Amortization	$2	$2	$1

Goodwill_Details

Goodwill (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012	Sep. 30, 2012
Goodwill [Line Items]
Goodwill, Gross	$3,429		$3,330		$3,319
Accumulated impairment losses	-492		-492		-492
Changes in the carrying amount of goodwill by operating segment
Goodwill, Beginning Balance	2,838		2,827
Purchase price allocation adjustments	13		-1
Goodwill acquired during the year	184		16
Goodwill disposed of during the year	-48		-14
Goodwill impairment charge	0		0		-492
Foreign exchange	-50		11
Other movements	0	[1]	-1	[1]
Goodwill, Ending Balance	2,937		2,838		2,827
Global
Goodwill [Line Items]
Goodwill, Gross	1,234		1,145		1,127
Accumulated impairment losses	0		0		0
Changes in the carrying amount of goodwill by operating segment
Goodwill, Beginning Balance	1,145		1,127
Purchase price allocation adjustments	3		0
Goodwill acquired during the year	5		15
Goodwill disposed of during the year	0		0
Foreign exchange	-7		3
Other movements	88	[1]	0	[1]
Goodwill, Ending Balance	1,234		1,145
North America
Goodwill [Line Items]
Goodwill, Gross	1,686		1,776		1,792	1,782
Accumulated impairment losses	-492		-492		-492
Changes in the carrying amount of goodwill by operating segment
Goodwill, Beginning Balance	1,284		1,300			1,290
Purchase price allocation adjustments	3		-1
Goodwill acquired during the year	0		0
Goodwill disposed of during the year	-48		-14
Foreign exchange	0		0
Other movements	-45	[1]	-1	[1]
Goodwill, Ending Balance	1,194		1,284			1,290
International
Goodwill [Line Items]
Goodwill, Gross	509		409		400
Accumulated impairment losses	0		0		0
Changes in the carrying amount of goodwill by operating segment
Goodwill, Beginning Balance	409		400
Purchase price allocation adjustments	7		0
Goodwill acquired during the year	179		1
Goodwill disposed of during the year	0		0
Foreign exchange	-43		8
Other movements	-43	[1]	0	[1]
Goodwill, Ending Balance	$509		$409
[1]	{F|ahBzfndlYmZpbGluZ3MtaHJkcmoLEgZYTUxEb2MiXlhCUkxEb2NHZW5JbmZvOjc2NWQ0YzNjODdhMTRmZmZiZWExNGQ4NmZhNTg0MTgxfFRleHRTZWxlY3Rpb246NDRDRkFFMTAzOEI1MTYxOUQ4NDJDRDA1RjU1MEI5MjAM}

Other_Intangible_Assets_Net_De

Other Intangible Assets, Net (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Summary of major classes of amortizable intangible assets
Gross carrying amount	$771	$685
Accumulated amortization	-321	-332
Total	450	353
Client relationships
Summary of major classes of amortizable intangible assets
Gross carrying amount	689	671
Accumulated amortization	-316	-326
Total	373	345
Management contracts [Member]
Summary of major classes of amortizable intangible assets
Gross carrying amount	71	0
Accumulated amortization	-1	0
Total	70	0
Other Intangible Assets [Member]
Summary of major classes of amortizable intangible assets
Gross carrying amount	11	14
Accumulated amortization	-4	-6
Total	$7	$8

Other_Intangible_Assets_Net_De1

Other Intangible Assets, Net (Details 1) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Estimated aggregate amortization of intangible assets for each of the next five years
2014	$57
2015	51
2016	46
2017	41
2018	37
Thereafter	218
Total	450	353
Aggregate amortization of intangible assets	$54	$55	$59

Other_Assets_Details

Other Assets (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Other current assets
Prepayments and accrued income	$81	$73
Income taxes receivable	30	32
Deferred Compensation Plan Assets Current	17	26
Other receivables	86	66
Total other current assets	214	197
Other non-current assets
Deferred compensation plan assets	92	88
Income Taxes Receivable, Noncurrent	0	21
Accounts Receivable, Net, Noncurrent	29	28
Investments and Other Noncurrent Assets	29	19
Other receivables	70	50
Total other non-current assets	220	206
Total other assets	$434	$403

Other_Liabilities_Details

Other Liabilities (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Other current liabilities
Accounts payable	$131	$123
Accrued dividends payable	55	51
Accrual for Taxes Other than Income Taxes, Current	44	51
Deferred Compensation Liability, Current	17	26
Other payables	197	164
Total other current liabilities	444	415
Other non-current liabilities
Incentives from lessors	171	183
Deferred compensation plan liability	92	89
Accounts Payable	26	13
Accounts Payable	14	6
Taxes Payable	15	40
Other payables	71	43
Total other non-current liabilities	389	374
Total other liabilities	$833	$789

Allowance_for_Doubtful_Account2

Allowance for Doubtful Accounts (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Provision for Liabilities
Beginning balance	$13	$14	$13
Additions/ (releases) charged to costs and expenses	4	3	16
Deductions / Other movements	-6	-4	-15
Foreign exchange differences	1
Ending balance	$12	$13	$14

Pension_Plans_Details

Pension Plans (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Change in plan assets
Employer contributions	($122)	($150)	($143)
Components on the Consolidated Balance Sheets
Pension benefits asset	314	278
Liability for pension benefits	-284	-136
UK Pension Benefits
Change in benefit obligation
Benefit obligation, beginning of year	2,785	2,582
Service cost	41	37	35
Interest cost	121	109	108
Employee contributions	2	2
Actuarial loss (gain)	390	79
Benefits paid	-85	-78
Foreign currency changes	-168	54
Benefit obligations, end of year	3,084	2,785	2,582
Change in plan assets
Fair value of plan assets, beginning of year	3,061	2,716
Actual return on plan assets	520	255
Employee contributions	2	2
Employer contributions	91	100
Benefits paid	-85	-78
Foreign currency changes	-191	66
Fair value of plan assets, end of year	3,398	3,061	2,716
Funded status at end of year	314	276
Components on the Consolidated Balance Sheets
Pension benefits asset	314	276
Liability for pension benefits	0	0
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Curtailments	-2
US Pension Benefits
Change in benefit obligation
Benefit obligation, beginning of year	864	958
Service cost	0	0	0
Interest cost	40	38	41
Employee contributions	0	0
Actuarial loss (gain)	183	-81
Benefits paid	-36	-51
Foreign currency changes	0	0
Benefit obligations, end of year	1,051	864	958
Change in plan assets
Fair value of plan assets, beginning of year	757	708
Actual return on plan assets	65	60
Employee contributions	0	0
Employer contributions	20	40
Benefits paid	-36	-51
Foreign currency changes	0	0
Fair value of plan assets, end of year	806	757	708
Funded status at end of year	-245	-107
Components on the Consolidated Balance Sheets
Pension benefits asset	0	0
Liability for pension benefits	($245)	($107)

Pension_Plans_Details_1

Pension Plans (Details 1) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
UK Pension Benefits
Amounts recognized in accumulated other comprehensive loss
Net actuarial loss	$809	$815
Prior service gain	-20	-24
US Pension Benefits
Amounts recognized in accumulated other comprehensive loss
Net actuarial loss	399	233
Prior service gain	$0	$0

Pension_Plans_Details_2

Pension Plans (Details 2) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Components of net periodic benefit cost
Net periodic benefit cost (income)	($17)	($4)	$2
Net actuarial loss (gain)	274	-83	203
Amortization of unrecognized actuarial loss, Before tax amount	-48	-55	-47
Other changes in plan assets and benefit obligations recognized in other comprehensive income (loss)
Prior service gain	4	5	6
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax	179	-118	193
UK Pension Benefits
Components of net periodic benefit cost
Service cost	41	37	35
Interest cost	121	109	108
Expected return on plan assets	-213	-191	-181
Amortization of unrecognized prior service gain	-4	-5	-6
Amortization of unrecognized actuarial loss	42	45	39
Curtailment gain	-2
Net periodic benefit cost (income)	-13	-5	-5
Net actuarial loss (gain)	83	15	141
Amortization of unrecognized actuarial loss, Before tax amount	-42	-45	-39
Other changes in plan assets and benefit obligations recognized in other comprehensive income (loss)
Prior service gain	4	5	6
Other Comprehensive Income (Loss), Finalization of Pension and Other Postretirement Benefit Plan Valuation, Tax	-2	0	0
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax	43	-25	108
Total recognized in net periodic benefit cost and other comprehensive loss (income)	30	-30	103
US Pension Benefits
Components of net periodic benefit cost
Service cost	0	0	0
Interest cost	40	38	41
Expected return on plan assets	-54	-51	-46
Amortization of unrecognized prior service gain	0	0	0
Amortization of unrecognized actuarial loss	6	9	8
Net periodic benefit cost (income)	-8	-4	3
Net actuarial loss (gain)	172	-90	37
Amortization of unrecognized actuarial loss, Before tax amount	-6	-9	-8
Other changes in plan assets and benefit obligations recognized in other comprehensive income (loss)
Prior service gain	0	0	0
Other Comprehensive Income (Loss), Finalization of Pension and Other Postretirement Benefit Plan Valuation, Tax	0	0	0
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax	166	-99	29
Total recognized in net periodic benefit cost and other comprehensive loss (income)	$158	($103)	$32

Pension_Plans_Details_3

Pension Plans (Details 3) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014
UK Pension Benefits
Estimated net loss and prior service cost to be amortized from accumulated other comprehensive loss into net periodic benefit cost
Estimated net loss	$39
Prior service gain	-3
US Pension Benefits
Estimated net loss and prior service cost to be amortized from accumulated other comprehensive loss into net periodic benefit cost
Estimated net loss	11
Prior service gain	$0

Pension_Plans_Details_4

Pension Plans (Details 4)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
UK Pension Benefits
Weighted-average assumptions to determine benefit obligations:
Discount rate	3.60%	4.40%
Rate of compensation increase	2.90%	3.20%
Weighted-average assumptions to determine net periodic benefit cost:
Discount rate	4.40%	4.40%
Expected return on plan assets	7.00%	7.30%
Rate of compensation increase	3.20%	2.30%
US Pension Benefits
Weighted-average assumptions to determine benefit obligations:
Discount rate	3.90%	4.80%
Weighted-average assumptions to determine net periodic benefit cost:
Discount rate	4.80%	4.10%
Expected return on plan assets	7.30%	7.30%

Pension_Plans_Details_5

Pension Plans (Details 5)	Dec. 31, 2014	Dec. 31, 2013
UK Pension Benefits
Pension plan asset allocations based on fair values:
Plan assets	100.00%	100.00%
US Pension Benefits
Pension plan asset allocations based on fair values:
Plan assets	100.00%	100.00%
Equity securities | UK Pension Benefits
Pension plan asset allocations based on fair values:
Plan assets	34.00%	36.00%
Equity securities | US Pension Benefits
Pension plan asset allocations based on fair values:
Plan assets	48.00%	52.00%
Debt securities | UK Pension Benefits
Pension plan asset allocations based on fair values:
Plan assets	45.00%	38.00%
Debt securities | US Pension Benefits
Pension plan asset allocations based on fair values:
Plan assets	49.00%	46.00%
Hedge funds | UK Pension Benefits
Pension plan asset allocations based on fair values:
Plan assets	14.00%	17.00%
Hedge funds | US Pension Benefits
Pension plan asset allocations based on fair values:
Plan assets	0.00%	0.00%
Real estate | UK Pension Benefits
Pension plan asset allocations based on fair values:
Plan assets	3.00%	3.00%
Real estate | US Pension Benefits
Pension plan asset allocations based on fair values:
Plan assets	0.00%	0.00%
Cash | UK Pension Benefits
Pension plan asset allocations based on fair values:
Plan assets	4.00%	6.00%
Cash | US Pension Benefits
Pension plan asset allocations based on fair values:
Plan assets	0.00%	0.00%
Other | UK Pension Benefits
Pension plan asset allocations based on fair values:
Plan assets	0.00%	0.00%
Other | US Pension Benefits
Pension plan asset allocations based on fair values:
Plan assets	3.00%	2.00%

Pension_Plans_Details_6

Pension Plans (Details 6) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
UK Pension Plan [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	$3,398	$3,061	$2,716
UK Pension Plan [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	3,398	3,061
UK Pension Plan [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	1,929	2,021
UK Pension Plan [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	759	371
UK Pension Plan [Member] | Level 3
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	710	669	507
UK Pension Plan [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	710	669
UK Pension Plan [Member] | US equities | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	750	740
UK Pension Plan [Member] | US equities | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	565	659
UK Pension Plan [Member] | US equities | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	185	81
UK Pension Plan [Member] | US equities | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
UK Pension Plan [Member] | UK equities | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	249	256
UK Pension Plan [Member] | UK equities | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	234	239
UK Pension Plan [Member] | UK equities | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	15	17
UK Pension Plan [Member] | UK equities | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
UK Pension Plan [Member] | Other equities | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	150	103
UK Pension Plan [Member] | Other equities | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	26	40
UK Pension Plan [Member] | Other equities | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	124	63
UK Pension Plan [Member] | Other equities | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
UK Pension Plan [Member] | US Government bonds | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	83	31
UK Pension Plan [Member] | US Government bonds | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	81	31
UK Pension Plan [Member] | US Government bonds | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	2	0
UK Pension Plan [Member] | US Government bonds | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
UK Pension Plan [Member] | UK Government bonds | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	789	656
UK Pension Plan [Member] | UK Government bonds | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	783	656
UK Pension Plan [Member] | UK Government bonds | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	6	0
UK Pension Plan [Member] | UK Government bonds | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
UK Pension Plan [Member] | Other Government bonds | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	105	107
UK Pension Plan [Member] | Other Government bonds | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	3	7
UK Pension Plan [Member] | Other Government bonds | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	3	0
UK Pension Plan [Member] | Other Government bonds | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	99	100
UK Pension Plan [Member] | UK corporate bonds | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	103	75
UK Pension Plan [Member] | UK corporate bonds | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	75
UK Pension Plan [Member] | UK corporate bonds | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	103	0
UK Pension Plan [Member] | UK corporate bonds | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
UK Pension Plan [Member] | All Other Corporate Bonds [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	146	151
UK Pension Plan [Member] | All Other Corporate Bonds [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	113	151
UK Pension Plan [Member] | All Other Corporate Bonds [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	33	0
UK Pension Plan [Member] | All Other Corporate Bonds [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
UK Pension Plan [Member] | Derivatives | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	293	154
UK Pension Plan [Member] | Derivatives | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
UK Pension Plan [Member] | Derivatives | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	293	154
UK Pension Plan [Member] | Derivatives | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
UK Pension Plan [Member] | Real estate | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	124	92
UK Pension Plan [Member] | Real estate | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
UK Pension Plan [Member] | Real estate | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
UK Pension Plan [Member] | Real estate | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	124	92
UK Pension Plan [Member] | Cash | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	137	163
UK Pension Plan [Member] | Cash | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	124	163
UK Pension Plan [Member] | Cash | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	13	0
UK Pension Plan [Member] | Cash | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
UK Pension Plan [Member] | Hedge funds | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	487	505
UK Pension Plan [Member] | Hedge funds | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
UK Pension Plan [Member] | Hedge funds | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	28
UK Pension Plan [Member] | Hedge funds | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	487	477
UK Pension Plan [Member] | Other Other Investments [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	-18	28
UK Pension Plan [Member] | Other Other Investments [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
UK Pension Plan [Member] | Other Other Investments [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	-18	28
UK Pension Plan [Member] | Other Other Investments [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
US Pension Plan [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	806	757	708
US Pension Plan [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	806	757
US Pension Plan [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	304	303
US Pension Plan [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	502	454
US Pension Plan [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
US Pension Plan [Member] | US equities | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	232	245
US Pension Plan [Member] | US equities | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	115	120
US Pension Plan [Member] | US equities | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	117	125
US Pension Plan [Member] | US equities | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
US Pension Plan [Member] | Other equities | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	154	149
US Pension Plan [Member] | Other equities | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	110	116
US Pension Plan [Member] | Other equities | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	44	33
US Pension Plan [Member] | Other equities | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
US Pension Plan [Member] | US Government bonds | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	72	55
US Pension Plan [Member] | US Government bonds | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
US Pension Plan [Member] | US Government bonds | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	72	55
US Pension Plan [Member] | US Government bonds | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
US Pension Plan [Member] | Mortgage backed securities | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	16	12
US Pension Plan [Member] | Mortgage backed securities | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
US Pension Plan [Member] | Mortgage backed securities | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	16	12
US Pension Plan [Member] | Mortgage backed securities | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
US Pension Plan [Member] | Other Other Investments [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	28	15
US Pension Plan [Member] | Other Other Investments [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	20	9
US Pension Plan [Member] | Other Other Investments [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	8	6
US Pension Plan [Member] | Other Other Investments [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
US Pension Plan [Member] | Domestic Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	171	151
US Pension Plan [Member] | Domestic Corporate Debt Securities [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
US Pension Plan [Member] | Domestic Corporate Debt Securities [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	171	151
US Pension Plan [Member] | Domestic Corporate Debt Securities [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
US Pension Plan [Member] | Fixed Income Securities [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	101	100
US Pension Plan [Member] | Fixed Income Securities [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	59	58
US Pension Plan [Member] | Fixed Income Securities [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	42	42
US Pension Plan [Member] | Fixed Income Securities [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
US Pension Plan [Member] | Municipal Bonds [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	32	30
US Pension Plan [Member] | Municipal Bonds [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
US Pension Plan [Member] | Municipal Bonds [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	32	30
US Pension Plan [Member] | Municipal Bonds [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	$0	$0

Pension_Plans_Details_7

Pension Plans (Details 7) (UK Pension Plan [Member], USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Changes in the UK pension plan's Level 3 assets
Benefit obligations, end of year	$3,084	$2,785	$2,582
Foreign currency changes	-191	66
Level 3
Changes in the UK pension plan's Level 3 assets
Purchases, sales, issuances and settlements, net	40	121
Defined Benefit Plan, Actual Return on Plan Assets Still Held	24	29
Foreign currency changes	($23)	$12

Pension_Plans_Details_8

Pension Plans (Details 8) (USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
UK Pension Plan [Member]
Expected future benefit payments
2014	$83
2015	84
2016	87
2017	89
2018	92
2019-2023	505
US Pension Plan [Member]
Expected future benefit payments
2014	41
2015	43
2016	46
2017	49
2018	51
2019-2023	$284

Pension_Plans_Details_9

Pension Plans (Details 9) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Change in plan assets
Employer contributions	($122)	($150)	($143)
Components on the Consolidated Balance Sheets
Pension benefits asset	314	278
Liability for pension benefits	-284	-136
International Pension Benefits [Member]
Change in benefit obligation
Benefit obligation, beginning of year	195	180
Service cost	3	3	3
Interest cost	7	7	7
Actuarial loss (gain)	38	-5
Benefits paid	-9	-6
Reclassification from other non-current liabilities (i)	0	10
Foreign currency changes	-24	6
Benefit obligations, end of year	210	195	180
Change in plan assets
Fair value of plan assets, beginning of year	168	150
Actual return on plan assets	25	9
Employer contributions	11	10
Benefits paid	-9	-6
Foreign currency changes	-24	5
Fair value of plan assets, end of year	171	168	150
Funded status at end of year	-39	-27
Components on the Consolidated Balance Sheets
Pension benefits asset	0	2
Liability for pension benefits	($39)	($29)

Pension_Plans_Details_10

Pension Plans (Details 10) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Components of net periodic benefit cost
Net periodic benefit cost (income)	($17)	($4)	$2
Other changes in plan assets and benefit obligations recognized in other comprehensive income (loss)
Amortization of unrecognized actuarial loss	-48	-55	-47
Net actuarial loss (gain)	274	-83	203
Domestic Pension Plans of Foreign Entity, Defined Benefit [Member]
Components of net periodic benefit cost
Service cost	3	3	3
Interest cost	7	7	7
Expected return on plan assets	-6	-6	-6
Amortization of unrecognized actuarial loss	0	1	0
Net periodic benefit cost (income)	4	5	4
Other changes in plan assets and benefit obligations recognized in other comprehensive income (loss)
Amortization of unrecognized actuarial loss	0	-1	0
Net actuarial loss (gain)	19	-8	25
Total recognized in other comprehensive loss (income)	19	-9	25
Total recognized in net periodic benefit cost and other comprehensive loss (income)	$23	($4)	$29

Pension_Plans_Details_11

Pension Plans (Details 11) (International Pension Benefits [Member])	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Minimum [Member]
Weighted-average assumptions to determine benefit obligations:
Discount rate	2.00%	3.30%
Rate of compensation increase	2.00%	2.00%
Weighted-average assumptions to determine net periodic benefit cost:
Discount rate	3.30%	2.50%
Expected return on plan assets	2.00%	2.00%
Rate of compensation increase	2.00%	2.00%
Maximum [Member]
Weighted-average assumptions to determine benefit obligations:
Discount rate	3.60%	4.40%
Rate of compensation increase	3.50%	2.00%
Weighted-average assumptions to determine net periodic benefit cost:
Discount rate	4.40%	4.40%
Expected return on plan assets	4.66%	4.66%
Rate of compensation increase	2.50%	2.50%

Pension_Plans_Details_12

Pension Plans (Details 12) (International Pension Benefits [Member])	Dec. 31, 2014	Dec. 31, 2013
Asset Category
Equity securities	100.00%	100.00%
Equity securities
Asset Category
Equity securities	24.00%	35.00%
Debt securities
Asset Category
Equity securities	40.00%	39.00%
Real estate [Member]
Asset Category
Equity securities	3.00%	3.00%
Derivative instruments [Member]
Asset Category
Equity securities	13.00%	14.00%
Other Assets [Member]
Asset Category
Equity securities	20.00%	9.00%

Pension_Plans_Details_13

Pension Plans (Details 13) (International Pension Benefits [Member], USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	$171	$168	$150
Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	171	168
Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	134	133
Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	23	23
Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	14	12
US equities | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	18	29
US equities | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	18	29
US equities | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
US equities | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
UK equities | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	4	5
UK equities | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	4	5
UK equities | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
UK equities | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
Overseas equities [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	18	26
Overseas equities [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	18	26
Overseas equities [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
Overseas equities [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
Other Government bonds | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	65	61
Other Government bonds | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	65	61
Other Government bonds | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
Other Government bonds | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
Corporate Bond Securities [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	4	4
Corporate Bond Securities [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	4	4
Corporate Bond Securities [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
Corporate Bond Securities [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
Derivative instruments [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	23	23
Derivative instruments [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
Derivative instruments [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	23	23
Derivative instruments [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
Real estate [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	6	5
Real estate [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
Real estate [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
Real estate [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	6	5
Cash [Member] | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	11	8
Cash [Member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	11	8
Cash [Member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
Cash [Member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
Other Investments [member] | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	22	7
Other Investments [member] | Level 1 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	14	0
Other Investments [member] | Level 2 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	0	0
Other Investments [member] | Level 3 | Fair Value, Measurements, Recurring [Member]
Schedule of defined benefit pension plan assets fair value measured on a recurring basis
Pension benefits asset	$8	$7

Pension_Plans_Details_14

Pension Plans (Details 14) (International Pension Benefits [Member], USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
International Pension Benefits [Member]
Expected future benefit payments
2014	$5
2015	6
2016	6
2017	6
2018	6
2019-2023	$32

Pension_Plans_Details_Textual

Pension Plans (Details Textual) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure (Textual) [Abstract]
Pension benefits asset	$314	$278
Liability for pension benefits	284	136
Percentage matching contributions other than for former HRH employees			75.00%
Defined Contribution Plan, Employer Discretionary Contribution Amount	15	15	10
US Pension Benefits
Defined Benefit Plan Disclosure (Textual) [Abstract]
Pension benefits asset	0	0
Liability for pension benefits	245	107
Expected return on plan assets	7.30%	7.30%
Number of funds invested in assets	18
Expected contribution to defined pension plan for the full year 2012	10
Accumulated other comprehensive income (loss) net actuarial	399	233
Accumulated benefit obligation	1,051	864
US Pension Benefits | US and foreign equities [Member]
Defined Benefit Plan Disclosure (Textual) [Abstract]
Expected return on plan assets	11.00%
Defined benefit plan broad target allocation percentage of assets	50.00%
US Pension Benefits | Debt securities
Defined Benefit Plan Disclosure (Textual) [Abstract]
Expected return on plan assets	3.60%
Defined benefit plan broad target allocation percentage of assets	50.00%
UK Pension Benefits
Defined Benefit Plan Disclosure (Textual) [Abstract]
Pension benefits asset	314	276
Liability for pension benefits	0	0
Expected return on plan assets	7.00%	7.30%
Number of portfolios in which plan's assets divided	13
Number of managers managing plan's assets portfolios	10
Defined benefit plan estimated employer contributions including exceptional contributions in next fiscal year	96
Defined Benefit Contributions salary sacrifice next fiscal year	10
Accumulated other comprehensive income (loss) net actuarial	809	815
Accumulated benefit obligation	3,017	2,701
Curtailment gain	-2
UK Pension Benefits | UK and foreign equities [Member]
Defined Benefit Plan Disclosure (Textual) [Abstract]
Expected return on plan assets	8.86%
Defined benefit plan broad target allocation percentage of assets	36.50%
UK Pension Benefits | Real estate [Member]
Defined Benefit Plan Disclosure (Textual) [Abstract]
Expected return on plan assets	6.53%
Defined benefit plan broad target allocation percentage of assets	5.00%
UK Pension Benefits | Debt securities
Defined Benefit Plan Disclosure (Textual) [Abstract]
Expected return on plan assets	4.38%
Defined benefit plan broad target allocation percentage of assets	44.00%
UK Pension Benefits | Hedge funds
Defined Benefit Plan Disclosure (Textual) [Abstract]
Expected return on plan assets	8.38%
Defined benefit plan broad target allocation percentage of assets	15.00%
International Pension Benefits [Member]
Defined Benefit Plan Disclosure (Textual) [Abstract]
Pension benefits asset	0	2
Liability for pension benefits	39	29
Expected contribution to defined pension plan for the full year 2012	10
Net pension benefit liability	39	27
Accumulated other comprehensive income (loss) net actuarial	-42	-27
Accumulated benefit obligation	203	191
Estimated net loss for the international defined benefit plans amortized from accumulated other comprehensive loss into net periodic benefit cost over the next fiscal year	$1

Debt_ShortTerm_Debt_Details

Debt (Short-Term Debt) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Short-term Debt [Line Items]
Document Fiscal Year Focus	2014
Short-term debt and current portion of long-term debt
Short-term Debt	$167	$15
Short-term debt and current portion of long-term debt	167	15
Seven Year Term Loan Facility [Member]
Short-term debt and current portion of long-term debt
Current portion of 7-year term loan facility expires 2018	17	15
Maturity period of debt instrument	7 years
Five Point Six Two Five Percent Senior Notes Due Two Thousand Fifteen [Member]
Short-term debt and current portion of long-term debt
Senior Notes, Current	148	0
Fair Value Adjustment On Five Point Six Two Five Percentage Senior Notes Due Two Thousand Fifteen [Member]
Short-term debt and current portion of long-term debt
Senior Notes, Current	1	0
Term Loan Facility Expires Twenty Fifteen [Member]
Short-term debt and current portion of long-term debt
Current portion of 7-year term loan facility expires 2018	$1	$0
Maturity period of debt instrument	3 years

Debt_LongTerm_Debt_Details

Debt (Long-Term Debt) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Document Fiscal Year Focus	2014
Long - term debt
Long-term debt	$2,142	$2,311
Analysis of interest expense
Total interest expense	135	126	128
Revolving Credit Facility [Member]
Long - term debt
Revolving credit facility	0	0
Seven Year Term Loan Facility [Member]
Long - term debt
Long term debt	242	259
Maturity period of debt instrument	7 years
Analysis of interest expense
Total interest expense	5	6	6
5.625% senior notes due 2015
Long - term debt
Long-term debt	0	148
Interest rate on debt	5.63%	5.63%
Analysis of interest expense
Total interest expense	8	12	12
Fair Value adjustment on 5.625% senior notes due 2015 [Member]
Long - term debt
Long-term debt	0	4
Interest rate on debt	5.63%
4.125% senior notes due 2016 [Member]
Long - term debt
Long-term debt	299	299
Interest rate on debt	4.13%
Analysis of interest expense
Total interest expense	13	13	13
6.200% senior notes due 2017 [Member]
Long - term debt
Long-term debt	394	394
Interest rate on debt	6.20%	6.20%
Analysis of interest expense
Total interest expense	25	33	38
7.000% senior notes due 2019 [Member]
Long - term debt
Long-term debt	187	187
Interest rate on debt	7.00%	7.00%
Analysis of interest expense
Total interest expense	14	18	21
5.750% senior notes due 2021 [Member]
Long - term debt
Long-term debt	497	496
Interest rate on debt	5.75%
4.625% Senior Notes Due 2023 [Member]
Long - term debt
Long-term debt	249	249
Interest rate on debt	4.63%	4.63%
Analysis of interest expense
Total interest expense	11	4	0
Six Point One Two Five Percent Senior Notes Due Two Thousand Forty Three [Member]
Long - term debt
Long-term debt	274	274
Interest rate on debt	6.13%
Analysis of interest expense
Total interest expense	16	6	0
Term Loan Facility Expires Twenty Fifteen [Member]
Long - term debt
Long term debt	0	1
Maturity period of debt instrument	3 years
Other [Member]
Analysis of interest expense
Total interest expense	$6	$3	$8

Debt_Details_Textual

Debt (Details Textual) (USD $)	1 Months Ended	12 Months Ended				7 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2011	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Jul. 23, 2013	Apr. 28, 2014	Dec. 30, 2013	Jul. 23, 2018
Debt Instrument [Line Items]
Interest Expense		$135	$126	$128
Debt (Textual) [Abstract]
Settlement received on close out of interest rate swap			13
Loss on extinguishment of debt		0	60	0
Payments of Debt Extinguishment Costs		0	65	0
Principal amount of specific notes tendered and accepted for purchase			525
Proceeds from Issuance of Medium-term Notes	800	0	522	0
Repayments of debt		15	536	15
Document Fiscal Year Focus		2014
Excess of interest rate over LIBOR Year 2016		1.50%
Excess of interest rate over LIBOR Year One		1.70%
Excess of interest rate over LIBOR Thereafter		1.85%
Write off of unamortized debt issuance costs associated with debt repurchase		0	2	0
Write Down Of The Fair Value Adjustment To The Carrying Value Of Senior Notes In Connection With Interest Rate Swap		0	7	0
Maturity date of interest rate swaps		15-Jul-15
Senior Notes Due 2015 [Member]
Debt (Textual) [Abstract]
Interest rate on debt		5.63%
Debt Instrument, Face Amount		350
Revolving Credit Facility [Member]
Debt (Textual) [Abstract]
Revolving credit facility		0	0
Revolving $200 million credit facility [Member]
Debt (Textual) [Abstract]
Revolving credit facility		22
Other Lines Credit Facility [Member]
Debt (Textual) [Abstract]
Revolving credit facility		3	4
Revolving credit facility		1	0
Revolving Credit Facility One [Member]
Debt Instrument [Line Items]
Interest Expense		4	0	0
Debt (Textual) [Abstract]
Revolving credit facility		400					300
Interest Expense [Member]
Debt Instrument [Line Items]
Interest Expense		135	126	128
4.625% Senior Notes Due 2023 [Member]
Debt Instrument [Line Items]
Interest Expense		11	4	0
Debt (Textual) [Abstract]
Interest rate on debt		4.63%	4.63%
Debt Instrument, Face Amount			250
Effective interest rate		4.70%
Senior notes, outstanding balance		249	249
5.625% senior notes due 2015
Debt Instrument [Line Items]
Interest Expense		8	12	12
Debt (Textual) [Abstract]
Interest rate on debt		5.63%	5.63%
Early Repayment of Senior Debt			202
Senior notes, outstanding balance		0	148
Fair Value adjustment on 5.625% senior notes due 2015 [Member]
Debt (Textual) [Abstract]
Interest rate on debt		5.63%
Write Down Of The Fair Value Adjustment To The Carrying Value Of Senior Notes In Connection With Interest Rate Swap					7
Senior notes, outstanding balance		0	4
4.125% senior notes due 2016 [Member]
Debt Instrument [Line Items]
Interest Expense		13	13	13
Debt (Textual) [Abstract]
Interest rate on debt		4.13%
Senior notes, outstanding balance		299	299
6.200% senior notes due 2017 [Member]
Debt Instrument [Line Items]
Interest Expense		25	33	38
Debt (Textual) [Abstract]
Interest rate on debt		6.20%	6.20%
Early Repayment of Senior Debt			206
Senior notes, outstanding balance		394	394
7.000% senior notes due 2019 [Member]
Debt Instrument [Line Items]
Interest Expense		14	18	21
Debt (Textual) [Abstract]
Interest rate on debt		7.00%	7.00%
Early Repayment of Senior Debt			113
Senior notes, outstanding balance		187	187
Seven Year Term Loan Facility [Member]
Debt Instrument [Line Items]
Interest Expense		5	6	6
Debt (Textual) [Abstract]
Debt 5-year term loan		242	259
Debt Instrument, Face Amount		300
Repayments of debt		15
Interest of Loan facility Description		LIBOR plus 1.50%
Facility expiration date		23-Jul-18				16-Dec-16
Outstanding Term Loan Facility Balance						281
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Interest Expense		3	2	1
Debt (Textual) [Abstract]
Revolving credit facility						500		800
Revolving credit facility		0
Interest of Loan facility Description		LIBOR plus 1.50%
5.750% senior notes due 2021 [Member]
Debt Instrument [Line Items]
Interest Expense		30	29	29
Debt (Textual) [Abstract]
Interest rate on debt		5.75%
Other [Member]
Debt Instrument [Line Items]
Interest Expense		6	3	8
Six Point One Two Five Percent Senior Notes Due Two Thousand Forty Three [Member]
Debt Instrument [Line Items]
Interest Expense		16	6	0
Debt (Textual) [Abstract]
Interest rate on debt		6.13%
Debt Instrument, Face Amount		275
Effective interest rate		6.15%
Senior notes, outstanding balance		274	274
Interest Expense [Member]
Debt (Textual) [Abstract]
Write off of unamortized debt issuance costs associated with debt repurchase			2
Debt [Member] | Seven Year Term Loan Facility [Member]
Debt (Textual) [Abstract]
Final repayment for credit facility									$186

Provisions_for_Liabilities_Det

Provisions for Liabilities (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Analysis of movements on provisions for liabilities
Beginning Balance	$206		$180
Net provisions made during the year	24		34
Amounts transferred to provisions in year	5		13
Utilized in the year	-34		-23
Foreign currency translation adjustment	-7		2
Ending Balance	194		206		180
Insurance recoveries recognized	0		0		10
Claims, lawsuits and other proceedings
Analysis of movements on provisions for liabilities
Beginning Balance	164	[1]	152	[1]
Net provisions made during the year	19	[1]	28	[1]
Amounts transferred to provisions in year	0		0
Utilized in the year	-31	[1]	-17	[1]
Foreign currency translation adjustment	-4	[1]	1	[1]
Ending Balance	148	[1]	164	[1]
Other provisions
Analysis of movements on provisions for liabilities
Beginning Balance	42	[2]	28	[2]
Net provisions made during the year	5	[2]	6	[2]
Amounts transferred to provisions in year	5		13
Utilized in the year	-3	[2]	-6	[2]
Foreign currency translation adjustment	-3	[2]	1	[2]
Ending Balance	46	[2]	42	[2]
Provision for vacant property	$4		$10
[1]	The claims, lawsuits and other proceedings provision includes E&O cases which represents management’s assessment of liabilities that may arise from asserted and unasserted claims for alleged errors and omissions that arise in the ordinary course of the Group’s business. Where some of the potential liability is recoverable under the Group’s external insurance arrangements, the full assessment of the liability is included in the provision with the associated insurance recovery shown separately as an asset.
[2]	The ‘Other’ category includes amounts relating to vacant property provisions of $4 million (2013: $10 million).

Commitments_and_Contingencies_1

Commitments and Contingencies (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Debt Instrument [Line Items]
Capital Lease Obligations	$11		$11
Unrecognized Tax Benefits	19		41	37	16
Contractual obligations
Contractual Obligation	4,953
2014	546
Payments due by 2015-2016	1,403
Payments due by 2017-2018	798
After 2019	2,206
Unrecognised tax benefits - net liability	19
Revolving Credit Facility [Member]
Contractual obligations
Contractual Obligation	7
2014	2
Payments due by 2015-2016	4
Payments due by 2017-2018	1
After 2019	0
Revolving $500 million credit facility [Member]
Contractual obligations
Contractual Obligation	2
2014	1
Payments due by 2015-2016	1
Payments due by 2017-2018	0
After 2019	0
5-year term loan facility expires 2016 [Member]
Contractual obligations
Contractual Obligation	259
2014	17
Payments due by 2015-2016	45
Payments due by 2017-2018	197
After 2019	0
Interest on term loan [Member]
Contractual obligations
Contractual Obligation	14
2014	4
Payments due by 2015-2016	8
Payments due by 2017-2018	2
After 2019	0
5.625% senior notes due 2015
Debt Instrument [Line Items]
Interest rate on debt	5.63%		5.63%
Contractual obligations
Contractual Obligation	148
2014	148
Payments due by 2015-2016	0
Payments due by 2017-2018	0
After 2019	0
Fair Value adjustment on 5.625% senior notes due 2015 [Member]
Debt Instrument [Line Items]
Interest rate on debt	5.63%
4.125% senior notes due 2016 [Member]
Debt Instrument [Line Items]
Interest rate on debt	4.13%
Contractual obligations
Contractual Obligation	300
2014	0
Payments due by 2015-2016	300
Payments due by 2017-2018	0
After 2019	0
6.200% senior notes due 2017 [Member]
Debt Instrument [Line Items]
Interest rate on debt	6.20%		6.20%
Contractual obligations
Contractual Obligation	394
2014	0
Payments due by 2015-2016	394
Payments due by 2017-2018	0
After 2019	0
7.000% senior notes due 2019 [Member]
Debt Instrument [Line Items]
Interest rate on debt	7.00%		7.00%
Contractual obligations
Contractual Obligation	187
2014	0
Payments due by 2015-2016	0
Payments due by 2017-2018	187
After 2019	0
5.750% senior notes due 2021 [Member]
Debt Instrument [Line Items]
Interest rate on debt	5.75%
Contractual obligations
Contractual Obligation	500
2014	0
Payments due by 2015-2016	0
Payments due by 2017-2018	0
After 2019	500
4.625% Senior Notes Due 2023 [Member]
Debt Instrument [Line Items]
Interest rate on debt	4.63%		4.63%
Contractual obligations
Contractual Obligation	250
2014	0
Payments due by 2015-2016	0
Payments due by 2017-2018	0
After 2019	250
Six Point One Two Five Percent Senior Notes Due Two Thousand Forty Three [Member]
Debt Instrument [Line Items]
Interest rate on debt	6.13%
Contractual obligations
Contractual Obligation	275
2014	0
Payments due by 2015-2016	0
Payments due by 2017-2018	0
After 2019	275
Interest on Senior Notes [Member]
Contractual obligations
Contractual Obligation	896
2014	112
Payments due by 2015-2016	173
Payments due by 2017-2018	137
After 2019	474
Total debt and related interest [Member]
Contractual obligations
Contractual Obligation	3,232
2014	284
Payments due by 2015-2016	925
Payments due by 2017-2018	524
After 2019	1,499
Operating leases [Member]
Contractual obligations
Contractual Obligation	1,181	[1]
2014	128	[1]
Payments due by 2015-2016	221	[1]
Payments due by 2017-2018	175	[1]
After 2019	657	[1]
Pensions [Member]
Contractual obligations
Contractual Obligation	346
2014	116
Payments due by 2015-2016	190
Payments due by 2017-2018	40
After 2019	0
Other contractual obligations [Member]
Contractual obligations
Contractual Obligation	143	[2]
2014	10	[2]
Payments due by 2015-2016	40	[2]
Payments due by 2017-2018	43	[2]
After 2019	50	[2]
Contingent Consideration Type [Domain]
Contractual obligations
Contractual Obligation	51	[2]
2014	8	[2]
Payments due by 2015-2016	27	[2]
Payments due by 2017-2018	16	[2]
After 2019	$0	[2]
[1]	Presented gross of sublease income.
[2]	Other contractual obligations include capital lease commitments, put option obligations and investment fund capital call obligations, the timing of which are included at the earliest point they may fall due.

Commitments_and_Contingencies_2

Commitments and Contingencies (Details 1) (USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Future minimum rental commitments under all non-cancellable operating lease agreements
2014	$546
Thereafter	2,206
Contractual Obligation	4,953
Gross rental commitments
Future minimum rental commitments under all non-cancellable operating lease agreements
2014	128
2015	115
2016	106
2017	91
2018	84
Thereafter	657
Contractual Obligation	1,181
Rentals from subleases
Future minimum rental commitments under all non-cancellable operating lease agreements
2014	-13
2015	-13
2016	-12
2017	-7
2018	-5
Thereafter	-10
Contractual Obligation	-60
Net rental commitments
Future minimum rental commitments under all non-cancellable operating lease agreements
2014	115
2015	102
2016	94
2017	84
2018	79
Thereafter	647
Contractual Obligation	$1,121

Commitments_and_Contingencies_3

Commitments and Contingencies (Details Textual)

1 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

In Millions, unless otherwise specified

Mar. 31, 2012

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2009

Jul. 31, 2010

Dec. 31, 2014

31-May-11

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2014

Dec. 30, 2013

Jul. 23, 2013

Dec. 31, 2014

Dec. 31, 2014

USD ($)

USD ($)

USD ($)

Trident V LP [Member]

Trident V Parallel Fund [Member]

Trident V Parallel Fund [Member]

Dowling Capital Partners I [Member]

Dowling Capital Partners I [Member]

Nashville property [Member]

Nashville property [Member]

UK Pension Benefits

Pension Plan [Member]

London headquarters building [Member]

London headquarters building [Member]

London headquarters building [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

United States dollar

United Kingdom, Pounds

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

GBP (£)

Line of Credit Facility [Abstract]

Line of Credit Facility, Amount Outstanding

$0

Revolving credit facility

800

500

Operating Leases [Abstract]

Term of operating lease

25 years

Gross rental commitments

645

719

Annual rentals per year

134

141

135

36

36

Subleased premises

29.00%

29.00%

Term of sublease

15 years

Amount received from sublease

51

66

76

Loss Contingency [Abstract]

Capital contributions

10

7

7

22

7

Other contractual obligations

64

63

Capital commitments

25

25

10

Defined Contribution Plan, On-going Contribution, Percent

15.90%

Defined benefit plan estimated deficit funding contributions in next fiscal year

56

Contingent Pension Commitment Profit

20.00%

Earnings Before Interest Tax Depreciation and Amortization

900

Contingent Pension Commitment Exceptional Shareholder Returns

10.00%

Exceptional return contribution in next fiscal year

21

Maximum Contributions Payable

486

312

Defined Benefit Contributions salary sacrifice next fiscal year

10

Defined benefit plan estimated employer contributions including exceptional contributions in next fiscal year

96

116

Original non cancellable lease term

Original non-cancellable lease terms typically are between 10 and 20 years

Rental income from subleases

13

15

17

Defined benefit plan estimated employer contributions excluding exceptional contributions in next fiscal year

75

Defined benefit plan estimated employer ongoing contributions in next fiscal year

19

Operating lease obligations subject to guarantees

756

828

Capital Lease Obligations

11

11

Current Fiscal Year End Date

-19

Guarantees to bankers and other third parties

20

11

Amount payable from options

$72

$12

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Loss, Net of Tax (Other Comprehensive Income (Loss)) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Foreign currency translation adjustments, Before tax amount	($183)	$20	$46
Foreign currency translation adjustments, Tax	0	0	0
Foreign currency translation adjustment, Net of tax amount	-183	20	46
Foreign currency translation on pension funding adjustments, Before tax amount	49	-15	-31
Foreign currency translation on pension funding adjustments, Tax	-12	5	9
Foreign currency translation on pension funding adjustments, Net of tax amount	37	-10	-22
Net actuarial (loss) gain, Before tax amount	-274	83	-203
Net actuarial (loss) gain, Tax	19	2	36
Net actuarial (loss) gain, Net of tax amount	-255	85	-167
Amortization of unrecognized actuarial loss, Before tax amount	48	55	47
Amortization of unrecognized actuarial loss, Tax	-8	-9	-9
Amortization of unrecognized actuarial loss, Net of tax amount	40	46	38
Amortization of unrecognized prior service gain, Before tax amount	-4	-5	-6
Amortization of unrecognized prior service gain, Tax	1	1	1
Amortization of unrecognized prior service gain, Net of tax amount	-3	-4	-5
Other Comprehensive (Income) Loss, Curtailment gain before tax	2	0	0
Other Comprehensive (Income) Loss, Curtailment gain, tax	0	0	0
Other Comprehensive (Income) Loss, Curtailment gain, net of tax	2	0	0
Pension funding adjustments, Before tax amount	-179	118	-193
Pension funding adjustments, Tax	0	-1	37
Pension funding adjustment, net of tax	-179	117	-156
Gain on derivatives (effective element), Net of tax amount	-25	23	11
Reclassification adjustment on derivatives, Before tax amount	-10	4	9
Reclassification adjustment on derivatives, Tax	2	-1	-2
Reclassification adjustment on derivatives, Net of tax amount	-8	3	7
Derivative instruments adjustment, Before tax amount	-21	25	5
Derivative instruments adjustment, Tax	4	-5	-1
Derivative instruments adjustment, net of tax	-17	20	4
Other comprehensive income, Before tax amount	-383	163	-142
Other comprehensive income, Tax	4	-6	36
Other comprehensive (loss) income, net of tax	-379	157	-106
Less: Other comprehensive income attributable to noncontrolling interests, Before tax amount	6	0	0
Less: Other comprehensive income attributable to noncontrolling interests, Tax	0	0	0
Less: Other comprehensive income attributable to noncontrolling interests, Net of tax amount	6	0	0
Other comprehensive income attributable to Willis Group Holdings, Before tax amount	-377	163	-142
Other comprehensive income attributable to Willis Group Holdings, Tax	4	-6	36
Comprehensive income attributable to Willis Group Holdings, Net of tax amount	-373	157	-106
Interest Rate Swaps [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Gain on derivatives (effective element), Before tax amount	0	0	3
Gain on derivatives (effecitve element), Tax	0	0	-1
Gain on derivatives (effective element), Net of tax amount	0	0	2
Reclassification adjustment on derivatives, Before tax amount	-5	-5	-5
Reclassification adjustment on derivatives, Tax	1	1	1
Reclassification adjustment on derivatives, Net of tax amount	-4	-4	-4
Forward Exchange Contracts [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Gain on derivatives (effective element), Before tax amount	-31	10	11
Gain on derivatives (effecitve element), Tax	6	-2	-2
Gain on derivatives (effective element), Net of tax amount	-25	8	9
Reclassification adjustment on derivatives, Before tax amount	16	1	-4
Reclassification adjustment on derivatives, Tax	-3	0	1
Reclassification adjustment on derivatives, Net of tax amount	13	1	-3
Treasury Lock [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Gain on derivatives (effective element), Before tax amount	0	19	0
Gain on derivatives (effecitve element), Tax	0	-4	0
Gain on derivatives (effective element), Net of tax amount	0	15	0
Reclassification adjustment on derivatives, Before tax amount	-1	0	0
Reclassification adjustment on derivatives, Tax	0	0	0
Reclassification adjustment on derivatives, Net of tax amount	($1)	$0	$0

Accumulated_Other_Comprehensiv3

Accumulated Other Comprehensive Loss, Net of Tax (Accumuulated Other Comprehensive Loss) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net foreign currency translation adjustment
Net foreign currency translation adjustment, beginning balance	($14)	($34)	($80)
Net foreign currency translation adjustment, Net current year other comprehensive income (loss), net of tax and noncontrolling interest	-177	20	46
Net foreign currency translation adjustment, Amounts reclassified from accumulated other comprehensive income	0	0	0
Net foreign currency translation adjustment, ending balance	-191	-14	-34
Pension funding adjustment
Pension funding adjustment, beginning balance	-714	-831	-675
Pension funding adjustment, Other comprehensive (loss) income before reclassifications	-216	75	-189
Pension funding adjustment, Amounts reclassified from accumulated other comprehensive income	37	42	33
Pension funding adjustment, Net current year other comprehensive income (loss), net of tax and noncontrolling interest	-179	117	-156
Pension funding adjustment, ending balance	-893	-714	-831
Net unrealized gain on derivative instruments
Net unrealized gain on derivative instruments, beginning balance	35	15	11
Net unrealized gain on derivative instruments, Other comprehensive (loss) income before reclassifications	-25	23	11
Net unrealized gain on derivative instruments, Amounts reclassified from accumulated other comprehensive income	8	-3	-7
Net unrealized gain on derivative instruments, Net current year other comprehensive income (loss), net of tax and noncontrolling interest	-17	20	4
Net unrealized gain on derivative instruments, ending balance	18	35	15
Total
Accumulated other comprehensive loss, net of tax, beginning balance	-693	-850	-744
Accumulated other comprehensive loss, net of tax, Other comprehensive (loss) income before reclassifications	-418	118	-132
Accumulated other comprehensive loss, net of tax, Amounts reclassified from accumulated other comprehensive income	45	39	26
Comprehensive income attributable to Willis Group Holdings, Net of tax amount	-373	157	-106
Accumulated other comprehensive loss, net of tax, ending balance	($1,066)	($693)	($850)

Accumulated_Other_Comprehensiv4

Accumulated Other Comprehensive Loss, Net of Tax (Reclassification from AOCI) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	$10		($4)		($9)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax	-2		1		2
Net unrealized gain on derivative instruments, Amounts reclassified from accumulated other comprehensive income	8		-3		-7
Prior service gain	4		5		6
Net actuarial loss	48		55		47
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, before Tax	44		50		41
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, Tax	-7		-8		-8
Pension funding adjustment, Amounts reclassified from accumulated other comprehensive income	37		42		33
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	45		39		26
Interest Rate Swaps [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	5		5		5
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax	-1		-1		-1
Net unrealized gain on derivative instruments, Amounts reclassified from accumulated other comprehensive income	4		4		4
Treasury Lock [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	1		0		0
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax	0		0		0
Net unrealized gain on derivative instruments, Amounts reclassified from accumulated other comprehensive income	1		0		0
Investment Income [Member] | Interest Rate Swaps [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	-5	[1]	-5	[1]	-5	[1]
Other Nonoperating Income (Expense) [Member] | Forward Contracts [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	16	[1]	1	[1]	-4	[1]
Interest Expense [Member] | Treasury Lock [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	-1		0		0
Operating Expense [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Prior service gain	-4		-5		-6
Net actuarial loss	($48)		($55)		($47)
[1]	OCI means other comprehensive income.

Equity_and_Noncontrolling_Inte2

Equity and Noncontrolling Interests (Details 1) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net Income (Loss) Attributable to Parent	$76	($7)	$47	$246	$68	($27)	$105	$219	$362	$365	($446)
Transfers from Noncontrolling Interest:
Decrease in Willis Group Holdings’ paid-in capital for purchase of noncontrolling interest									0	-4	-31
Increase in Willis Group Holdings’ paid-in capital for sale of noncontrolling interest									0	0	2
Net transfers from noncontrolling interests									0	-4	-29
Change from net income attributable to Willis Group Holdings and transfers from noncontrolling interests									$362	$361	($475)

Supplemental_Disclosures_of_Ca2

Supplemental Disclosures of Cash Flow Information (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Supplemental disclosures of cash flow information:
Cash payments for income taxes, net	$88	$61	$63
Cash payments for interest	123	117	118
Supplemental disclosures of non-cash flow investing and financing activities:
Write-off of unamortized debt issuance costs	0	-2	0
Write Down Of The Fair Value Adjustment To The Carrying Value Of Senior Notes In Connection With Interest Rate Swap	0	7	0
Assets acquired under capital leases	3	7	2
Deferred payments on acquisitions of subsidiaries	10	2	4
Acquisitions:
Fair value of assets acquired	296	47	23
Less:
Liabilities assumed	107	30	3
Cash acquired	57	1	0
Net assets acquired, net of cash acquired	$132	$16	$20

Derivative_Financial_Instrumen2

Derivative Financial Instruments and Hedging Activities (Details 1) (Foreign Exchange Contract [Member], USD $)	Dec. 31, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
US dollar [Member]
Derivative [Line Items]
Derivative, Notional Amount	$678	[1]	$303
Euro [Member]
Derivative [Line Items]
Derivative, Notional Amount	186	[1]	97
Japanese yen [Member]
Derivative [Line Items]
Derivative, Notional Amount	$51	[1]	$35
[1]	Forward exchange contracts range in maturity from 2015 to 2017.

Derivative_Financial_Instrumen3

Derivative Financial Instruments and Hedging Activities (Details 2) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Jun. 30, 2012
In Millions, unless otherwise specified
Assets:
Derivative assets financial and hedging instruments, fair value	$26	$23
Liabilities:
Derivative liabilities financial and hedging instruments, fair value	21	2
Forward Contracts [Member] | Other Assets [Member]
Assets:
Derivative assets financial and hedging instruments, fair value	26	23
Forward Contracts [Member] | Other Liabilities [Member]
Liabilities:
Derivative liabilities financial and hedging instruments, fair value	21	2
Cash Flow Hedging [Member] | Interest Rate Swaps [Member]
Assets:
Derivative assets financial and hedging instruments, fair value			$16

Derivative_Financial_Instrumen4

Derivative Financial Instruments and Hedging Activities (Details 3) (Cash Flow Hedging [Member], USD $)	12 Months Ended						3 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012		Sep. 30, 2014
Derivatives in cash flow hedging relationships [Abstract]
Amount of gain (loss) recognized in OCI on derivative (effective element)	($31)	[1]	$0	[1]	$14	[1]
Amount of gain (loss) reclassified from accumulated OCI into income (effective element)	10	[1]	-4	[1]	-9	[1]
Amount of gain (loss) recognized in income on derivative (ineffective hedges and ineffective element of effective hedges)	-1		3		1
Interest Rate Swaps [Member]
Derivatives in cash flow hedging relationships [Abstract]
Amount of gain (loss) recognized in OCI on derivative (effective element)	0	[1]	29	[1]	3	[1]
Interest Rate Swaps [Member] | Investment Income [Member]
Derivatives in cash flow hedging relationships [Abstract]
Amount of gain (loss) reclassified from accumulated OCI into income (effective element)	-5	[1]	-5	[1]	-5	[1]
Interest Rate Swaps [Member] | Operating Expense [Member]
Derivatives in cash flow hedging relationships [Abstract]
Amount of gain (loss) recognized in income on derivative (ineffective hedges and ineffective element of effective hedges)	0		0		0
Treasury Lock [Member]
Derivatives in cash flow hedging relationships [Abstract]
Amount of gain (loss) recognized in OCI on derivative (effective element)	0	[1]	19	[1]			19	[1]
Treasury Lock [Member] | Interest Expense [Member]
Derivatives in cash flow hedging relationships [Abstract]
Amount of gain (loss) reclassified from accumulated OCI into income (effective element)	-1	[1]	0	[1]
Amount of gain (loss) recognized in income on derivative (ineffective hedges and ineffective element of effective hedges)	0		2
Forward Contracts [Member]
Derivatives in cash flow hedging relationships [Abstract]
Amount of gain (loss) recognized in OCI on derivative (effective element)	-31	[1]	10	[1]	11	[1]
Forward Contracts [Member] | Operating Expense [Member]
Derivatives in cash flow hedging relationships [Abstract]
Amount of gain (loss) reclassified from accumulated OCI into income (effective element)	16	[1]	1	[1]	-4	[1]
Forward Contracts [Member] | Interest Expense [Member]
Derivatives in cash flow hedging relationships [Abstract]
Amount of gain (loss) recognized in income on derivative (ineffective hedges and ineffective element of effective hedges)	($1)		$1		$1
[1]	OCI means other comprehensive income.

Derivative_Financial_Instrumen5

Derivative Financial Instruments and Hedging Activities (Details Textual) (USD $)

12 Months Ended

3 Months Ended

In Millions, unless otherwise specified

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Sep. 30, 2014

Sep. 30, 2013

Mar. 31, 2014

Dec. 30, 2013

Jul. 23, 2013

Jun. 30, 2012

Derivative Instruments, Gain (Loss) [Line Items]

Net derivative (gains) reclassified from accumulated comprehensive income into earnings within the next twelve months

$7

Derivative Financial Instruments and Hedging Activities (Textual) [Abstract]

Current Fiscal Year End Date

-19

Derivative Asset, Fair Value, Gross Asset

26

23

Settlement received on close out of interest rate swap

13

Write Down Of The Fair Value Adjustment To The Carrying Value Of Senior Notes In Connection With Interest Rate Swap

0

7

0

Maturity date of interest rate swaps

15-Jul-15

Senior Notes [Member]

Derivative Financial Instruments and Hedging Activities (Textual) [Abstract]

Offer to repurchase 5.125% senior notes due July 2010

2,054

Senior Notes Due 2015 [Member]

Derivative Financial Instruments and Hedging Activities (Textual) [Abstract]

Offer to repurchase 5.125% senior notes due July 2010

350

Percentage of loan notes

5.63%

Seven Year Term Loan Facility [Member]

Derivative Financial Instruments and Hedging Activities (Textual) [Abstract]

5-year term loan facility balance

259

Maturity period of term loan

7 years

Description of variable rate basis

LIBOR

Basis spread on variable rate

1.50%

Revolving credit facility [Member]

Derivative Financial Instruments and Hedging Activities (Textual) [Abstract]

Revolving credit facility

0

0

Description of variable rate basis

LIBOR

Basis spread on variable rate

1.50%

Revolving $200 million credit facility [Member]

Derivative Financial Instruments and Hedging Activities (Textual) [Abstract]

Revolving credit facilities available

22

Line of Credit Facility, Maximum Borrowing Capacity for Regulatory Purposes

20

Currency Swap [Member]

Derivative Financial Instruments and Hedging Activities (Textual) [Abstract]

Derivative, Notional Amount

352

228

Revolving Credit Facility [Member]

Derivative Financial Instruments and Hedging Activities (Textual) [Abstract]

Revolving credit facility

0

Revolving credit facilities available

800

500

4.625% Senior Notes Due 2023 [Member]

Derivative Financial Instruments and Hedging Activities (Textual) [Abstract]

Offer to repurchase 5.125% senior notes due July 2010

250

Percentage of loan notes

4.63%

4.63%

Long-term debt

249

249

Six Point One Two Five Percent Senior Notes Due Two Thousand Forty Three [Member]

Derivative Financial Instruments and Hedging Activities (Textual) [Abstract]

Offer to repurchase 5.125% senior notes due July 2010

275

Percentage of loan notes

6.13%

Long-term debt

274

274

Fair Value adjustment on 5.625% senior notes due 2015 [Member]

Derivative Financial Instruments and Hedging Activities (Textual) [Abstract]

Percentage of loan notes

5.63%

Write Down Of The Fair Value Adjustment To The Carrying Value Of Senior Notes In Connection With Interest Rate Swap

7

Long-term debt

0

4

Cash Flow Hedging [Member]

Derivative Instruments, Gain (Loss) [Line Items]

Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net

-31

[1]

0

[1]

14

[1]

Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net

-1

3

1

Cash Flow Hedging [Member] | Interest Rate Swaps [Member]

Derivative Instruments, Gain (Loss) [Line Items]

Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net

0

[1]

29

[1]

3

[1]

Derivative Financial Instruments and Hedging Activities (Textual) [Abstract]

Derivative Asset, Fair Value, Gross Asset

16

Gain on derivative

15

Expected gain to be recognized in income, next fiscal year

1

Cash Flow Hedging [Member] | Treasury Lock [Member]

Derivative Instruments, Gain (Loss) [Line Items]

Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net

0

[1]

19

[1]

19

[1]

Derivative Financial Instruments and Hedging Activities (Textual) [Abstract]

Gain on derivative

21

Cash Flow Hedging [Member] | Interest Expense [Member]

Derivative Financial Instruments and Hedging Activities (Textual) [Abstract]

foreign exchange gain loss recognised on forward exchange contracts

14

Cash Flow Hedging [Member] | Interest Expense [Member] | Treasury Lock [Member]

Derivative Instruments, Gain (Loss) [Line Items]

Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net

0

2

Fair Value Hedging [Member] | Interest Rate Swaps [Member]

Derivative Financial Instruments and Hedging Activities (Textual) [Abstract]

Derivative, Notional Amount

$350

[1]

OCI means other comprehensive income.

Fair_Value_Measurement_Details

Fair Value Measurement (Details) (Fair Value, Measurements, Recurring [Member], USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Assets at fair value:
Derivative financial instruments	$26	$23
Total assets	26	23
Liabilities at fair value:
Derivative Liability	21	2
Liabilities	21	2
Quoted prices in active markets for identical assets Level 1 [Member]
Assets at fair value:
Derivative financial instruments	0	0
Total assets	0	0
Liabilities at fair value:
Derivative Liability	0	0
Liabilities	0	0
Significant other observable inputs Level 2 [Member]
Assets at fair value:
Derivative financial instruments	26	23
Total assets	26	23
Liabilities at fair value:
Derivative Liability	21	2
Liabilities	21	2
Significant other unobservable inputs Level 3 [Member]
Assets at fair value:
Derivative financial instruments	0	0
Total assets	0	0
Liabilities at fair value:
Derivative Liability	0	0
Liabilities	$0	$0

Segment_Information_Details

Segment Information (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Information regarding operating segments
Commissions and fees									$3,767		$3,633		$3,458
Gross Investment Income, Operating									16		15		18
Other income									19		7		4
Total Revenues	958	812	935	1,097	919	795	890	1,051	3,802		3,655		3,480
Depreciation and amortization									146		149		138
Operating Income (Loss)									647		663		-225
International [Member]
Information regarding operating segments
Commissions and fees									1,016		926		874
Gross Investment Income, Operating									6		7		8
Other income									0		0		0
Total Revenues									1,022		933		882
Depreciation and amortization									27		22		23
Operating Income (Loss)									197		178		167
North America [Member]
Information regarding operating segments
Commissions and fees									1,365		1,349		1,281
Gross Investment Income, Operating									1		2		3
Other income									4		7		4
Total Revenues									1,370		1,358		1,288
Depreciation and amortization									71		77		76
Operating Income (Loss)									273		249		252
Global [Member]
Information regarding operating segments
Commissions and fees									1,386		1,358		1,303
Gross Investment Income, Operating									9		6		7
Other income									15		0		0
Total Revenues									1,410		1,364		1,310
Depreciation and amortization									36		36		33
Operating Income (Loss)									352		376		400
Total Operating Segments [Member]
Information regarding operating segments
Commissions and fees									3,767		3,633		3,458
Gross Investment Income, Operating									16		15		18
Other income									19		7		4
Total Revenues									3,802		3,655		3,480
Depreciation and amortization									134		135		132
Operating Income (Loss)									822		803		819
Corporate Segment [Member]
Information regarding operating segments
Commissions and fees									0		0		0
Gross Investment Income, Operating									0		0		0
Other income									0		0		0
Total Revenues									0		0		0
Depreciation and amortization									12	[1]	14	[1]	6	[1]
Operating Income (Loss)									($175)	[1]	($140)	[1]	($1,044)	[1]
[1]	See the following table for an analysis of the ‘Corporate and other’ line.

Fair_Value_Measurements_Fair_V

Fair Value Measurements Fair Value Measurements (Details 2) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Liabilities [Abstract]
Shot-term debt	$167	$15
Long-term debt	2,142	2,311
Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	635	796
Fiduciary Funds Restricted Fair Value Disclosure	1,888	1,662
Liabilities [Abstract]
Shot-term debt	167	15
Long-term debt	2,142	2,311
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	635	796
Fiduciary Funds Restricted Fair Value Disclosure	1,888	1,662
Liabilities [Abstract]
Short-term debt, Fair Value	169	15
Long-term debt, Fair Value	$2,327	$2,444

Segment_Information_Details_1

Segment Information (Details 1) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Segment Reporting Information [Line Items]
Costs Related to Group Functions	($194)		($118)		($114)
Non-servicing Element of Defined Benefit Plan	53		42		38
Significant Legal and Regulatory Settlement	-2		-6		-6
Restructuring Charges	-36
Write-off of uncollectible accounts receivable					-13
Corporate and other information
Additional incentive accrual, change in remuneration policy	0		0		-252
Write off of unamortized cash retention awards	0		0		-200
Goodwill and intangible asset impairment	0		0		-492
Joint venture settlement	0		0		-11
Insurance recoveries	0		0		10
OPERATING (LOSS) INCOME	647		663		-225
Parent Company [Member]
Segment Reporting Information [Line Items]
Costs and Expenses	-13		-10		-4
All Other Segments [Member]
Segment Reporting Information [Line Items]
Write-off of uncollectible accounts receivable	0		0
Corporate and other information
Expense Reduction Initiative	0		-46		0
Fees Related To The Extinguishment Of Debt	0		-1		0
Other Expenses	-2		-1		0
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Restructuring Charges	-17		0		0
Corporate and other information
OPERATING (LOSS) INCOME	($175)	[1]	($140)	[1]	($1,044)	[1]
[1]	See the following table for an analysis of the ‘Corporate and other’ line.

Fair_Value_Measurements_Fair_V1

Fair Value Measurements Fair Value Measurements (Details 3) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Goodwill, fair value	$2,937	$2,838	$2,827

Segment_Information_Details_2

Segment Information (Details 2) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Total consolidated operating income
Total consolidated operating income	$647	$663	($225)
Other Nonoperating Income (Expense)	6	22	16
Loss on extinguishment of debt	0	60	0
Interest expense	-135	-126	-128
Income (loss) before income taxes and interest in earnings of associates	$518	$499	($337)

Segment_Information_Details_3

Segment Information (Details 3) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Commissions and fees:
Retail insurance services									$2,534	$2,433	$2,320
Specialty insurance services									1,233	1,200	1,138
Total commissions and fees									3,767	3,633	3,458
Gross Investment Income, Operating									16	15	18
Other income									19	7	4
Total Revenues	958	812	935	1,097	919	795	890	1,051	3,802	3,655	3,480
International [Member]
Commissions and fees:
Retail insurance services									1,016	926	874
Specialty insurance services									0	0	0
Total commissions and fees									1,016	926	874
Gross Investment Income, Operating									6	7	8
Other income									0	0	0
Total Revenues									1,022	933	882
North America [Member]
Commissions and fees:
Retail insurance services									1,365	1,349	1,281
Specialty insurance services									0	0	0
Total commissions and fees									1,365	1,349	1,281
Gross Investment Income, Operating									1	2	3
Other income									4	7	4
Total Revenues									1,370	1,358	1,288
Global [Member]
Commissions and fees:
Retail insurance services									153	158	165
Specialty insurance services									1,233	1,200	1,138
Total commissions and fees									1,386	1,358	1,303
Gross Investment Income, Operating									9	6	7
Other income									15	0	0
Total Revenues									$1,410	$1,364	$1,310

Segment_Information_Details_4

Segment Information (Details 4) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Commissions and fees
Commissions and fees	$3,767	$3,633	$3,458
Fixed assets
Fixed assets	483	481
UNITED KINGDOM
Commissions and fees
Commissions and fees	1,027	1,026	980
Fixed assets
Fixed assets	232	233
US [Member]
Commissions and fees
Commissions and fees	1,592	1,549	1,484
Fixed assets
Fixed assets	193	203
Other [Member]
Commissions and fees
Commissions and fees	1,148	1,058	994
Fixed assets
Fixed assets	$58	$45

Segment_Information_Details_Te

Segment Information (Details Textual)	12 Months Ended
	Dec. 31, 2014
Segment information (Textual) [Abstract]
Commissions & fees and fixed assets from countries other than the UK and the US	10.00%

Subsidiary_Undertakings_Detail

Subsidiary Undertakings (Details)	12 Months Ended
	Dec. 31, 2014
TAI Limited [Member]
Schedule of Investments [Line Items]
Country of registration	England and Wales
Class of share	Ordinary shares
Percentage ownership	100.00%
Trinity Acquisition Limited [Member]
Schedule of Investments [Line Items]
Country of registration	England and Wales
Class of share	Ordinary shares
Percentage ownership	100.00%
Willis Faber Limited [Member]
Schedule of Investments [Line Items]
Country of registration	England and Wales
Class of share	Ordinary shares
Percentage ownership	100.00%
Willis Group Limited [Member]
Schedule of Investments [Line Items]
Country of registration	England and Wales
Class of share	Ordinary shares
Percentage ownership	100.00%
Willis Investment UK Holdings Limited Member
Schedule of Investments [Line Items]
Country of registration	England and Wales
Class of share	Ordinary shares
Percentage ownership	100.00%
Willis Netherlands Holdings B.V. [Member]
Schedule of Investments [Line Items]
Country of registration	Netherlands
Class of share	Ordinary shares
Percentage ownership	100.00%
Willis Europe B.V. [Member]
Schedule of Investments [Line Items]
Country of registration	England and Wales
Class of share	Ordinary shares
Percentage ownership	100.00%
Willis HRH, Inc. [Member]
Schedule of Investments [Line Items]
Country of registration	USA
Class of share	Common shares
Percentage ownership	100.00%
Willis Limited [Member]
Schedule of Investments [Line Items]
Country of registration	England and Wales
Class of share	Ordinary shares
Percentage ownership	100.00%
Willis North America, Inc. [Member]
Schedule of Investments [Line Items]
Country of registration	USA
Class of share	Common shares
Percentage ownership	100.00%
Willis Re, Inc. [Member]
Schedule of Investments [Line Items]
Country of registration	USA
Class of share	Common shares
Percentage ownership	100.00%

Financial_Information_for_Pare4

Financial Information for Parent Guarantor, Other Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Income Statement Disclosures) (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
REVENUES
Commissions and fees									$3,767	$3,633	$3,458
Gross Investment Income, Operating									16	15	18
Other income									19	7	4
Total Revenues	958	812	935	1,097	919	795	890	1,051	3,802	3,655	3,480
EXPENSES
Salaries and benefits									-2,314	-2,207	-2,475
Other operating expenses									-659	-636	-600
Depreciation expense									-92	-94	-79
Amortization of intangible assets									-54	-55	-59
Restructuring Costs									-36	0	0
Goodwill impairment charge									0	0	-492
Total expenses	-819	-778	-787	-771	-774	-725	-723	-770	-3,155	-2,992	-3,705
OPERATING (LOSS) INCOME									647	663	-225
Other Nonoperating Income (Expense)									6	22	16
Income from group undertakings									0	0	0
Expenses due to group undertakings									0	0	0
Loss on extinguishment of debt									0	-60	0
Interest expense									-135	-126	-128
(Loss) Income from continuing operations before income taxes and interest in earnings of associates									518	499	-337
Income taxes									-159	-122	-101
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									359	377	-438
Interest in earnings of associates, net of tax									14	0	5
EQUITY ACCOUNT FOR SUBSIDIARIES									0	0	0
Net income (loss)	83	-8	48	250	74	-27	107	223	373	377	-433
Less: net income attributable to noncontrolling interests									-11	-12	-13
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	76	-7	47	246	68	-27	105	219	362	365	-446
Parent Company [Member]
REVENUES
Commissions and fees									0	0	0
Gross Investment Income, Operating									0	0	0
Other income									0	0	0
Total Revenues									0	0	0
EXPENSES
Salaries and benefits									-1	-1	-2
Other operating expenses									-16	-5	-6
Depreciation expense									0	0	0
Amortization of intangible assets									0	0	0
Restructuring Costs									0
Goodwill impairment charge											0
Total expenses									-17	-6	-8
OPERATING (LOSS) INCOME									-17	-6	-8
Other Nonoperating Income (Expense)									-15	5	2
Income from group undertakings									0	0	0
Expenses due to group undertakings									0	-10	0
Loss on extinguishment of debt										0
Interest expense									-43	-42	-43
(Loss) Income from continuing operations before income taxes and interest in earnings of associates									-75	-53	-49
Income taxes									0	0	0
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									-75	-53	-49
Interest in earnings of associates, net of tax									0	0	0
EQUITY ACCOUNT FOR SUBSIDIARIES									437	418	-397
Net income (loss)									362	365	-446
Less: net income attributable to noncontrolling interests									0	0	0
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS									362	365	-446
Other Guarantors [Member]
REVENUES
Commissions and fees									0	0	0
Gross Investment Income, Operating									0	0	0
Other income									0	0	0
Total Revenues									0	0	0
EXPENSES
Salaries and benefits									0	0	0
Other operating expenses									-95	-69	-80
Depreciation expense									-4	-3	-1
Amortization of intangible assets									0	0	0
Restructuring Costs									-11
Goodwill impairment charge											0
Total expenses									-110	-72	-81
OPERATING (LOSS) INCOME									-110	-72	-81
Other Nonoperating Income (Expense)									-220	-4	-2
Income from group undertakings									221	191	201
Expenses due to group undertakings									-33	-34	-67
Loss on extinguishment of debt										0
Interest expense									-35	-16	-7
(Loss) Income from continuing operations before income taxes and interest in earnings of associates									-177	65	44
Income taxes									25	23	31
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									-152	88	75
Interest in earnings of associates, net of tax									10	9	8
EQUITY ACCOUNT FOR SUBSIDIARIES									570	320	-480
Net income (loss)									428	417	-397
Less: net income attributable to noncontrolling interests									0	0	0
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS									428	417	-397
The Issuer
REVENUES
Commissions and fees									8	8	0
Gross Investment Income, Operating									0	0	1
Other income									0	0	0
Total Revenues									8	8	1
EXPENSES
Salaries and benefits									-81	-103	-96
Other operating expenses									-38	-163	-78
Depreciation expense									-17	-20	-15
Amortization of intangible assets									0	0	0
Restructuring Costs									-3
Goodwill impairment charge											0
Total expenses									-139	-286	-189
OPERATING (LOSS) INCOME									-131	-278	-188
Other Nonoperating Income (Expense)									0	0	-1
Income from group undertakings									313	364	316
Expenses due to group undertakings									-179	-141	-147
Loss on extinguishment of debt										-60
Interest expense									-45	-63	-70
(Loss) Income from continuing operations before income taxes and interest in earnings of associates									-42	-178	-90
Income taxes									24	0	34
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									-18	-178	-56
Interest in earnings of associates, net of tax									0	0	0
EQUITY ACCOUNT FOR SUBSIDIARIES									76	150	-172
Net income (loss)									58	-28	-228
Less: net income attributable to noncontrolling interests									0	0	0
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS									58	-28	-228
Other
REVENUES
Commissions and fees									3,759	3,625	3,458
Gross Investment Income, Operating									16	15	17
Other income									19	7	4
Total Revenues									3,794	3,647	3,479
EXPENSES
Salaries and benefits									-2,232	-2,103	-2,377
Other operating expenses									-510	-399	-436
Depreciation expense									-71	-71	-63
Amortization of intangible assets									-54	-55	-59
Restructuring Costs									-22
Goodwill impairment charge											-492
Total expenses									-2,889	-2,628	-3,427
OPERATING (LOSS) INCOME									905	1,019	52
Other Nonoperating Income (Expense)									11	31	17
Income from group undertakings									102	86	111
Expenses due to group undertakings									-424	-456	-414
Loss on extinguishment of debt										0
Interest expense									-12	-5	-8
(Loss) Income from continuing operations before income taxes and interest in earnings of associates									582	675	-242
Income taxes									-208	-145	-166
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									374	530	-408
Interest in earnings of associates, net of tax									4	-9	-3
EQUITY ACCOUNT FOR SUBSIDIARIES									0	0	0
Net income (loss)									378	521	-411
Less: net income attributable to noncontrolling interests									-11	-12	-13
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS									367	509	-424
Consolidating adjustments
REVENUES
Commissions and fees									0	0	0
Gross Investment Income, Operating									0	0	0
Other income									0	0	0
Total Revenues									0	0	0
EXPENSES
Salaries and benefits									0	0	0
Other operating expenses									0	0	0
Depreciation expense									0	0	0
Amortization of intangible assets									0	0	0
Restructuring Costs									0
Goodwill impairment charge											0
Total expenses									0	0	0
OPERATING (LOSS) INCOME									0	0	0
Other Nonoperating Income (Expense)									230	-10	0
Income from group undertakings									-636	-641	-628
Expenses due to group undertakings									636	641	628
Loss on extinguishment of debt										0
Interest expense									0	0	0
(Loss) Income from continuing operations before income taxes and interest in earnings of associates									230	-10	0
Income taxes									0	0	0
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									230	-10	0
Interest in earnings of associates, net of tax									0	0	0
EQUITY ACCOUNT FOR SUBSIDIARIES									-1,083	-888	1,049
Net income (loss)									-853	-898	1,049
Less: net income attributable to noncontrolling interests									0	0	0
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS									($853)	($898)	$1,049

Financial_Information_for_Pare5

Financial Information for Parent Guarantor, Other Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Comprehensive Income Disclosures) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	($6)	$534	($539)
Less: Comprehensive income attributable to noncontrolling interests	-5	-12	-13
Comprehensive income attributable to Willis Group Holdings	-11	522	-552
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	-11	522	-552
Less: Comprehensive income attributable to noncontrolling interests	0	0	0
Comprehensive income attributable to Willis Group Holdings	-11	522	-552
Other Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	69	565	-494
Less: Comprehensive income attributable to noncontrolling interests	0	0	0
Comprehensive income attributable to Willis Group Holdings	69	565	-494
The Issuer
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	-110	74	-263
Less: Comprehensive income attributable to noncontrolling interests	0	0	0
Comprehensive income attributable to Willis Group Holdings	-110	74
Other
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	49	636	-519
Less: Comprehensive income attributable to noncontrolling interests	-5	-12	-13
Comprehensive income attributable to Willis Group Holdings	44	624	-532
Consolidating adjustments
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	-3	-1,263	1,289
Less: Comprehensive income attributable to noncontrolling interests	0	0	0
Comprehensive income attributable to Willis Group Holdings	($3)	($1,263)	$1,289

Financial_Information_for_Pare6

Financial Information for Parent Guarantor, Other Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Balance Sheet Disclosures) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Condensed Financial Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	$59	$0
CURRENT ASSETS
Cash and cash equivalents	635	796	500	436
Accounts receivable, net	1,044	1,041
Fiduciary assets	8,948	8,412
Deferred tax assets	12	15
Other current assets	214	197
Amounts owed by group undertakings	0	0
Total current assets	10,853	10,461
NON-CURRENT ASSETS
Investments in subsidiaries	0	0
Fixed assets, net	483	481
Goodwill	2,937	2,838	2,827
Other intangible assets, net	450	353
Investments in associates	169	176
Deferred tax assets	9	7
Pension benefits asset	314	278
Other non-current assets	220	206
Noncurrent amounts owed by group undertakings	0	0
Total non-current assets	4,582	4,339
TOTAL ASSETS	15,435	14,800
CURRENT LIABILITIES
Fiduciary liabilities	8,948	8,412
Deferred revenue and accrued expenses	619	586
Income taxes payable	33	21
Current portion of long-term debt	167	15
Deferred tax liabilities	21	25
Other current liabilities	444	415
Amounts due to group undertakings	0	0
Total current liabilities	10,232	9,474
NON-CURRENT LIABILITIES
Net liability investments in subsidiaries	0	0
Long-term debt	2,142	2,311
Liability for pension benefits	284	136
Deferred tax liabilities	128	56
Provisions for liabilities	194	206	180
Other non-current liabilities	389	374
Noncurrent amounts due to group undertakings	0	0
Total non-current liabilities	3,137	3,083
Total liabilities	13,369	12,557
EQUITY
Total Willis Group Holdings shareholders' equity	1,985	2,215
Noncontrolling interests	22	28
Total equity	2,007	2,243
TOTAL LIABILITIES AND EQUITY	15,435	14,800
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	0
CURRENT ASSETS
Cash and cash equivalents	9	3	1	0
Accounts receivable, net	0	0
Fiduciary assets	0	0
Deferred tax assets	0	0
Other current assets	1	1
Amounts owed by group undertakings	3,674	4,051
Total current assets	3,684	4,055
NON-CURRENT ASSETS
Investments in subsidiaries	0	0
Fixed assets, net	0	0
Goodwill	0	0
Other intangible assets, net	0	0
Investments in associates	0	0
Deferred tax assets	0	0
Pension benefits asset	0	0
Other non-current assets	3	4
Noncurrent amounts owed by group undertakings	0	0
Total non-current assets	3	4
TOTAL ASSETS	3,687	4,059
CURRENT LIABILITIES
Fiduciary liabilities	0	0
Deferred revenue and accrued expenses	1	2
Income taxes payable	0	0
Current portion of long-term debt	0	0
Deferred tax liabilities	0	0
Other current liabilities	67	62
Amounts due to group undertakings	0	0
Total current liabilities	68	64
NON-CURRENT LIABILITIES
Net liability investments in subsidiaries	838	985
Long-term debt	796	795
Liability for pension benefits	0	0
Deferred tax liabilities	0	0
Provisions for liabilities	0	0
Other non-current liabilities	0	0
Noncurrent amounts due to group undertakings	0	0
Total non-current liabilities	1,634	1,780
Total liabilities	1,702	1,844
EQUITY
Total Willis Group Holdings shareholders' equity	1,985	2,215
Noncontrolling interests	0	0
Total equity	1,985	2,215
TOTAL LIABILITIES AND EQUITY	3,687	4,059
Other Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	0
CURRENT ASSETS
Cash and cash equivalents	2	3	0	0
Accounts receivable, net	0	0
Fiduciary assets	0	0
Deferred tax assets	0	0
Other current assets	27	21
Amounts owed by group undertakings	924	903
Total current assets	953	927
NON-CURRENT ASSETS
Investments in subsidiaries	2,536	2,838
Fixed assets, net	20	15
Goodwill	0	0
Other intangible assets, net	0	0
Investments in associates	147	156
Deferred tax assets	0	0
Pension benefits asset	0	0
Other non-current assets	8	9
Noncurrent amounts owed by group undertakings	518	518
Total non-current assets	3,229	3,536
TOTAL ASSETS	4,182	4,463
CURRENT LIABILITIES
Fiduciary liabilities	0	0
Deferred revenue and accrued expenses	4	1
Income taxes payable	0	3
Current portion of long-term debt	17	15
Deferred tax liabilities	0	0
Other current liabilities	11	15
Amounts due to group undertakings	4,374	4,760
Total current liabilities	4,406	4,794
NON-CURRENT LIABILITIES
Net liability investments in subsidiaries	0	0
Long-term debt	765	782
Liability for pension benefits	0	0
Deferred tax liabilities	0	1
Provisions for liabilities	0	0
Other non-current liabilities	0	0
Noncurrent amounts due to group undertakings	0	0
Total non-current liabilities	765	783
Total liabilities	5,171	5,577
EQUITY
Total Willis Group Holdings shareholders' equity	-989	-1,114
Noncontrolling interests	0	0
Total equity	-989	-1,114
TOTAL LIABILITIES AND EQUITY	4,182	4,463
The Issuer
Condensed Financial Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	0
CURRENT ASSETS
Cash and cash equivalents	0	0	0	163
Accounts receivable, net	4	4
Fiduciary assets	0	0
Deferred tax assets	0	0
Other current assets	10	10
Amounts owed by group undertakings	1,057	1,317
Total current assets	1,071	1,331
NON-CURRENT ASSETS
Investments in subsidiaries	721	1,021
Fixed assets, net	42	51
Goodwill	0	0
Other intangible assets, net	0	0
Investments in associates	0	0
Deferred tax assets	0	0
Pension benefits asset	0	0
Other non-current assets	2	5
Noncurrent amounts owed by group undertakings	740	690
Total non-current assets	1,505	1,767
TOTAL ASSETS	2,576	3,098
CURRENT LIABILITIES
Fiduciary liabilities	0	0
Deferred revenue and accrued expenses	30	28
Income taxes payable	7	0
Current portion of long-term debt	149	0
Deferred tax liabilities	0	0
Other current liabilities	46	38
Amounts due to group undertakings	1,499	1,662
Total current liabilities	1,731	1,728
NON-CURRENT LIABILITIES
Net liability investments in subsidiaries	0	0
Long-term debt	581	733
Liability for pension benefits	0	0
Deferred tax liabilities	0	0
Provisions for liabilities	0	0
Other non-current liabilities	17	48
Noncurrent amounts due to group undertakings	518	518
Total non-current liabilities	1,116	1,299
Total liabilities	2,847	3,027
EQUITY
Total Willis Group Holdings shareholders' equity	-271	71
Noncontrolling interests	0	0
Total equity	-271	71
TOTAL LIABILITIES AND EQUITY	2,576	3,098
Other
Condensed Financial Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	59
CURRENT ASSETS
Cash and cash equivalents	624	790	499	273
Accounts receivable, net	1,040	1,037
Fiduciary assets	8,948	8,412
Deferred tax assets	12	16
Other current assets	205	186
Amounts owed by group undertakings	1,114	1,484
Total current assets	11,943	11,925
NON-CURRENT ASSETS
Investments in subsidiaries	0	0
Fixed assets, net	421	415
Goodwill	2,937	2,838
Other intangible assets, net	450	353
Investments in associates	22	20
Deferred tax assets	9	7
Pension benefits asset	314	278
Other non-current assets	207	188
Noncurrent amounts owed by group undertakings	0	0
Total non-current assets	4,360	4,099
TOTAL ASSETS	16,303	16,024
CURRENT LIABILITIES
Fiduciary liabilities	8,948	8,412
Deferred revenue and accrued expenses	584	555
Income taxes payable	55	39
Current portion of long-term debt	1	0
Deferred tax liabilities	21	25
Other current liabilities	320	300
Amounts due to group undertakings	896	1,333
Total current liabilities	10,825	10,664
NON-CURRENT LIABILITIES
Net liability investments in subsidiaries	0	0
Long-term debt	0	1
Liability for pension benefits	284	136
Deferred tax liabilities	128	55
Provisions for liabilities	194	206
Other non-current liabilities	372	326
Noncurrent amounts due to group undertakings	740	690
Total non-current liabilities	1,718	1,414
Total liabilities	12,543	12,078
EQUITY
Total Willis Group Holdings shareholders' equity	3,679	3,918
Noncontrolling interests	22	28
Total equity	3,701	3,946
TOTAL LIABILITIES AND EQUITY	16,303	16,024
Consolidating adjustments
Condensed Financial Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	0
CURRENT ASSETS
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	0	0
Fiduciary assets	0	0
Deferred tax assets	0	-1
Other current assets	-29	-21
Amounts owed by group undertakings	-6,769	-7,755
Total current assets	-6,798	-7,777
NON-CURRENT ASSETS
Investments in subsidiaries	-3,257	-3,859
Fixed assets, net	0	0
Goodwill	0	0
Other intangible assets, net	0	0
Investments in associates	0	0
Deferred tax assets	0	0
Pension benefits asset	0	0
Other non-current assets	0	0
Noncurrent amounts owed by group undertakings	-1,258	-1,208
Total non-current assets	-4,515	-5,067
TOTAL ASSETS	-11,313	-12,844
CURRENT LIABILITIES
Fiduciary liabilities	0	0
Deferred revenue and accrued expenses	0	0
Income taxes payable	-29	-21
Current portion of long-term debt	0	0
Deferred tax liabilities	0	0
Other current liabilities	0	0
Amounts due to group undertakings	-6,769	-7,755
Total current liabilities	-6,798	-7,776
NON-CURRENT LIABILITIES
Net liability investments in subsidiaries	-838	-985
Long-term debt	0	0
Liability for pension benefits	0	0
Deferred tax liabilities	0	0
Provisions for liabilities	0	0
Other non-current liabilities	0	0
Noncurrent amounts due to group undertakings	-1,258	-1,208
Total non-current liabilities	-2,096	-2,193
Total liabilities	-8,894	-9,969
EQUITY
Total Willis Group Holdings shareholders' equity	-2,419	-2,875
Noncontrolling interests	0	0
Total equity	-2,419	-2,875
TOTAL LIABILITIES AND EQUITY	($11,313)	($12,844)

Financial_Information_for_Pare7

Financial Information for Parent Guarantor, Other Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Cash Flow Disclosures) (Details) (USD $)	1 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2011	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Consolidated Statements of Cash Flows [Abstract]
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES		$477	$561	$525
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets		6	12	5
Additions to fixed assets		-113	-112	-135
Additions to intangible assets		-4	-7	-2
Acquisitions of operations, net of cash acquired		-241	-30	-33
Payments to acquire other investments		-10	-7	-7
Proceeds from Sale of Equity Method Investments		0	4	0
Proceeds from Divestiture of Businesses, Net of Cash Divested		86	20	0
Cash received on intercompany investing activities		0	0	0
Cash paid on intercompany investing activities		0	0	0
Additional investment in subsidiaries		0
Net cash (used in) provided by continuing investing activities		-276	-120	-172
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued	800	0	522	0
Debt issuance costs		-3	-8	0
Repayments of debt		-15	-536	-15
Payments of Debt Extinguishment Costs		0	-65	0
Proceeds from issue of other debt		0	0	1
Repurchase of shares		-213	0	-100
Proceeds from issue of shares		134	155	53
Excess tax benefits from share-based payment arrangements		5	2	2
Dividends paid		-210	-193	-185
Proceeds from Noncontrolling Interests		0	0	3
Acquisition of noncontrolling interests		-4	-4	-39
Dividends paid to noncontrolling interests		-17	-10	-11
Cash received on intercompany financing activities		0	0	0
Cash paid on intercompany financing activities		0	0	0
Net cash used in financing activities		-323	-137	-291
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS		-122	304	62
Effect of exchange rate changes on cash and cash equivalents		-39	-8	2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR		796	500	436
CASH AND CASH EQUIVALENTS, END OF YEAR		635	796	500
Parent Company [Member]
Consolidated Statements of Cash Flows [Abstract]
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES		-35	4	-23
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets		0	0	0
Additions to fixed assets		0	0	0
Additions to intangible assets		0	0	0
Acquisitions of operations, net of cash acquired		0	0	0
Payments to acquire other investments		0	0	0
Proceeds from Sale of Equity Method Investments			0
Proceeds from Divestiture of Businesses, Net of Cash Divested		0	0
Cash received on intercompany investing activities		361	383	256
Cash paid on intercompany investing activities		0	-347	0
Additional investment in subsidiaries		-31
Net cash (used in) provided by continuing investing activities		330	36	256
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued			0
Debt issuance costs		0	0
Repayments of debt		0	0	0
Payments of Debt Extinguishment Costs			0
Proceeds from issue of other debt				0
Repurchase of shares		-213		-100
Proceeds from issue of shares		134	155	53
Excess tax benefits from share-based payment arrangements		0	0	0
Dividends paid		-210	-193	-185
Payments to Noncontrolling Interests				0
Proceeds from Noncontrolling Interests				0
Acquisition of noncontrolling interests		0	0	0
Dividends paid to noncontrolling interests		0	0	0
Cash received on intercompany financing activities		0	0	0
Cash paid on intercompany financing activities		0	0	0
Net cash used in financing activities		-289	-38	-232
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS		6	2	1
Effect of exchange rate changes on cash and cash equivalents		0	0	0
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR		3	1	0
CASH AND CASH EQUIVALENTS, END OF YEAR		9	3	1
Other Guarantors [Member]
Consolidated Statements of Cash Flows [Abstract]
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES		387	125	1,504
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets		0	0	0
Additions to fixed assets		-9	-7	-7
Additions to intangible assets		0	0	0
Acquisitions of operations, net of cash acquired		0	-237	0
Payments to acquire other investments		0	0	0
Proceeds from Sale of Equity Method Investments			0
Proceeds from Divestiture of Businesses, Net of Cash Divested		0	0
Cash received on intercompany investing activities		0	211	216
Cash paid on intercompany investing activities		-53	-442	-318
Additional investment in subsidiaries		0
Net cash (used in) provided by continuing investing activities		-62	-475	-109
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued			522
Debt issuance costs		0	-8
Repayments of debt		-15	-15	-15
Payments of Debt Extinguishment Costs			0
Proceeds from issue of other debt				1
Repurchase of shares		0		0
Proceeds from issue of shares		0	0	0
Excess tax benefits from share-based payment arrangements		0	0	0
Dividends paid		0	0	0
Payments to Noncontrolling Interests				0
Acquisition of noncontrolling interests		-4	0	0
Dividends paid to noncontrolling interests		0	0	0
Cash received on intercompany financing activities		46	321	81
Cash paid on intercompany financing activities		-353	-467	-1,462
Net cash used in financing activities		-326	353	-1,395
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS		-1	3	0
Effect of exchange rate changes on cash and cash equivalents		0	0	0
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR		3	0	0
CASH AND CASH EQUIVALENTS, END OF YEAR		2	3	0
The Issuer
Consolidated Statements of Cash Flows [Abstract]
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES		265	7	-44
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets		1	3	0
Additions to fixed assets		-10	-11	-19
Additions to intangible assets		0	0	0
Acquisitions of operations, net of cash acquired		0	-230	0
Payments to acquire other investments		0	0	0
Proceeds from Sale of Equity Method Investments			0
Proceeds from Divestiture of Businesses, Net of Cash Divested		0	230
Cash received on intercompany investing activities		120	36	44
Cash paid on intercompany investing activities		-131	-120	-10
Additional investment in subsidiaries		0
Net cash (used in) provided by continuing investing activities		-20	-92	15
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued			0
Debt issuance costs		0	0
Repayments of debt		0	-521	0
Payments of Debt Extinguishment Costs			-65
Proceeds from issue of other debt				0
Repurchase of shares		0		0
Proceeds from issue of shares		0	0	0
Excess tax benefits from share-based payment arrangements		0	0	0
Dividends paid		0	-230	0
Payments to Noncontrolling Interests				0
Acquisition of noncontrolling interests		0	0	0
Dividends paid to noncontrolling interests		0	0	0
Cash received on intercompany financing activities		4	901	0
Cash paid on intercompany financing activities		-249	0	-134
Net cash used in financing activities		-245	85	-134
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS		0	0	-163
Effect of exchange rate changes on cash and cash equivalents		0	0	0
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR		0	0	163
CASH AND CASH EQUIVALENTS, END OF YEAR		0	0	0
Other
Consolidated Statements of Cash Flows [Abstract]
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES		212	662	-97
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets		6	9	5
Additions to fixed assets		-95	-94	-109
Additions to intangible assets		-4	-7	-2
Acquisitions of operations, net of cash acquired		-241	-30	-33
Payments to acquire other investments		-10	-7	-7
Proceeds from Sale of Equity Method Investments			4
Proceeds from Divestiture of Businesses, Net of Cash Divested		86	257
Cash received on intercompany investing activities		435	60	1,230
Cash paid on intercompany investing activities		-46	-780	-81
Additional investment in subsidiaries		0
Net cash (used in) provided by continuing investing activities		131	-588	1,003
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued			0
Debt issuance costs		-3	0
Repayments of debt		0	0	0
Payments of Debt Extinguishment Costs			0
Proceeds from issue of other debt				0
Repurchase of shares		0		0
Proceeds from issue of shares		31	0	0
Excess tax benefits from share-based payment arrangements		5	2	2
Dividends paid		-352	-7	-815
Proceeds from Noncontrolling Interests				3
Acquisition of noncontrolling interests		0	-4	-39
Dividends paid to noncontrolling interests		-17	-10	-11
Cash received on intercompany financing activities		180	467	328
Cash paid on intercompany financing activities		-314	-223	-150
Net cash used in financing activities		-470	225	-682
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS		-127	299	224
Effect of exchange rate changes on cash and cash equivalents		-39	-8	2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR		790	499	273
CASH AND CASH EQUIVALENTS, END OF YEAR		624	790	499
Consolidating adjustments
Consolidated Statements of Cash Flows [Abstract]
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES		-352	-237	-815
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets		-1	0	0
Additions to fixed assets		1	0	0
Additions to intangible assets		0	0	0
Acquisitions of operations, net of cash acquired		0	467	0
Payments to acquire other investments		0	0	0
Proceeds from Sale of Equity Method Investments			0
Proceeds from Divestiture of Businesses, Net of Cash Divested		0	-467
Cash received on intercompany investing activities		-916	-690	-1,746
Cash paid on intercompany investing activities		230	1,689	409
Additional investment in subsidiaries		31
Net cash (used in) provided by continuing investing activities		-655	999	-1,337
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued			0
Debt issuance costs		0	0
Repayments of debt		0	0	0
Payments of Debt Extinguishment Costs			0
Proceeds from issue of other debt				0
Repurchase of shares		0		0
Proceeds from issue of shares		-31	0	0
Excess tax benefits from share-based payment arrangements		0	0	0
Dividends paid		352	237	815
Payments to Noncontrolling Interests				0
Acquisition of noncontrolling interests		0	0	0
Dividends paid to noncontrolling interests		0	0	0
Cash received on intercompany financing activities		-230	-1,689	-409
Cash paid on intercompany financing activities		916	690	1,746
Net cash used in financing activities		1,007	-762	2,152
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS		0	0	0
Effect of exchange rate changes on cash and cash equivalents		0	0	0
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR		0	0	0
CASH AND CASH EQUIVALENTS, END OF YEAR		$0	$0	$0

Financial_Information_for_Pare8

Financial Information for Parent Guarantor, Other Guarantor Subsidiaries and Non-Guarantor Subsidiaries - Textuals (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 29, 2009	Mar. 28, 2007	Jul. 01, 2005
Condensed Financial Statements, Captions [Line Items]
Percentage of ownership in wholly on subsidiary by parent	100.00%
Willis North America, Inc. [Member]
Condensed Financial Statements, Captions [Line Items]
Senior notes, outstanding balance		$187	$394	$148

Financial_Information_for_Pare9

Financial Information for Parent Issuer, Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Income Statement Disclosures) (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
REVENUES
Commissions and fees									$3,767	$3,633	$3,458
Gross Investment Income, Operating									16	15	18
Other income									19	7	4
Total Revenues	958	812	935	1,097	919	795	890	1,051	3,802	3,655	3,480
EXPENSES
Salaries and benefits									-2,314	-2,207	-2,475
Other operating expenses									-659	-636	-600
Depreciation expense									-92	-94	-79
Amortization of intangible assets									-54	-55	-59
Restructuring Costs									-36	0	0
Goodwill impairment charge									0	0	-492
Total expenses	-819	-778	-787	-771	-774	-725	-723	-770	-3,155	-2,992	-3,705
OPERATING (LOSS) INCOME									647	663	-225
Income from group undertakings									0	0	0
Expenses due to group undertakings									0	0	0
Other Nonoperating Income (Expense)									6	22	16
Loss on extinguishment of debt									0	-60	0
Interest expense									-135	-126	-128
(Loss) Income from continuing operations before income taxes and interest in earnings of associates									518	499	-337
Income taxes									-159	-122	-101
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									359	377	-438
Interest in earnings of associates, net of tax									14	0	5
EQUITY ACCOUNT FOR SUBSIDIARIES									0	0	0
Net income (loss)	83	-8	48	250	74	-27	107	223	373	377	-433
Less: net income attributable to noncontrolling interests									-11	-12	-13
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	76	-7	47	246	68	-27	105	219	362	365	-446
Willis Group Holdings — the Parent Issuer
REVENUES
Commissions and fees									0	0	0
Gross Investment Income, Operating									0	0	0
Other income									0	0	0
Total Revenues									0	0	0
EXPENSES
Salaries and benefits									-1	-1	-2
Other operating expenses									-16	-5	-6
Depreciation expense									0	0	0
Amortization of intangible assets									0	0	0
Restructuring Costs									0
Goodwill impairment charge											0
Total expenses									-17	-6	-8
OPERATING (LOSS) INCOME									-17	-6	-8
Income from group undertakings									0	0	0
Expenses due to group undertakings									0	-10	0
Other Nonoperating Income (Expense)									-15	5	2
Loss on extinguishment of debt										0
Interest expense									-43	-42	-43
(Loss) Income from continuing operations before income taxes and interest in earnings of associates									-75	-53	-49
Income taxes									0	0	0
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									-75	-53	-49
Interest in earnings of associates, net of tax									0	0	0
EQUITY ACCOUNT FOR SUBSIDIARIES									437	418	-397
Net income (loss)									362	365	-446
Less: net income attributable to noncontrolling interests									0	0	0
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS									362	365	-446
The Guarantors
REVENUES
Commissions and fees									8	8	0
Gross Investment Income, Operating									0	0	1
Other income									0	0	0
Total Revenues									8	8	1
EXPENSES
Salaries and benefits									-81	-103	-96
Other operating expenses									-133	-232	-158
Depreciation expense									-21	-23	-16
Amortization of intangible assets									0	0	0
Restructuring Costs									-14
Goodwill impairment charge											0
Total expenses									-249	-358	-270
OPERATING (LOSS) INCOME									-241	-350	-269
Income from group undertakings									424	466	409
Expenses due to group undertakings									-102	-86	-106
Other Nonoperating Income (Expense)									-220	-4	-3
Loss on extinguishment of debt										-60
Interest expense									-80	-79	-77
(Loss) Income from continuing operations before income taxes and interest in earnings of associates									-219	-113	-46
Income taxes									49	23	65
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									-170	-90	19
Interest in earnings of associates, net of tax									10	9	8
EQUITY ACCOUNT FOR SUBSIDIARIES									588	498	-424
Net income (loss)									428	417	-397
Less: net income attributable to noncontrolling interests									0	0	0
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS									428	417	-397
Other
REVENUES
Commissions and fees									3,759	3,625	3,458
Gross Investment Income, Operating									16	15	17
Other income									19	7	4
Total Revenues									3,794	3,647	3,479
EXPENSES
Salaries and benefits									-2,232	-2,103	-2,377
Other operating expenses									-510	-399	-436
Depreciation expense									-71	-71	-63
Amortization of intangible assets									-54	-55	-59
Restructuring Costs									-22
Goodwill impairment charge											-492
Total expenses									-2,889	-2,628	-3,427
OPERATING (LOSS) INCOME									905	1,019	52
Income from group undertakings									102	86	111
Expenses due to group undertakings									-424	-456	-414
Other Nonoperating Income (Expense)									11	31	17
Loss on extinguishment of debt										0
Interest expense									-12	-5	-8
(Loss) Income from continuing operations before income taxes and interest in earnings of associates									582	675	-242
Income taxes									-208	-145	-166
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									374	530	-408
Interest in earnings of associates, net of tax									4	-9	-3
EQUITY ACCOUNT FOR SUBSIDIARIES									0	0	0
Net income (loss)									378	521	-411
Less: net income attributable to noncontrolling interests									-11	-12	-13
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS									367	509	-424
Consolidating adjustments
REVENUES
Commissions and fees									0	0	0
Gross Investment Income, Operating									0	0	0
Other income									0	0	0
Total Revenues									0	0	0
EXPENSES
Salaries and benefits									0	0	0
Other operating expenses									0	0	0
Depreciation expense									0	0	0
Amortization of intangible assets									0	0	0
Restructuring Costs									0
Goodwill impairment charge											0
Total expenses									0	0	0
OPERATING (LOSS) INCOME									0	0	0
Income from group undertakings									-526	-552	-520
Expenses due to group undertakings									526	552	520
Other Nonoperating Income (Expense)									230	-10	0
Loss on extinguishment of debt										0
Interest expense									0	0	0
(Loss) Income from continuing operations before income taxes and interest in earnings of associates									230	-10	0
Income taxes									0	0	0
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									230	-10	0
Interest in earnings of associates, net of tax									0	0	0
EQUITY ACCOUNT FOR SUBSIDIARIES									-1,025	-916	821
Net income (loss)									-795	-926	821
Less: net income attributable to noncontrolling interests									0	0	0
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS									($795)	($926)	$821

Recovered_Sheet2

Financial Information for Parent Issuer, Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Comprehensive Income Disclosures) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	($6)	$534	($539)
Less: Comprehensive income attributable to noncontrolling interests	-5	-12	-13
Comprehensive income attributable to Willis Group Holdings	-11	522	-552
Willis Group Holdings — the Parent Issuer
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	-11	522	-552
Less: Comprehensive income attributable to noncontrolling interests	0	0	0
Comprehensive income attributable to Willis Group Holdings	-11	522	-552
The Guarantors
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	69	565	-494
Less: Comprehensive income attributable to noncontrolling interests	0	0	0
Comprehensive income attributable to Willis Group Holdings	69	565	-494
Other
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	49	636	-519
Less: Comprehensive income attributable to noncontrolling interests	-5	-12	-13
Comprehensive income attributable to Willis Group Holdings	44	624	-532
Consolidating adjustments
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	-113	-1,189	1,026
Less: Comprehensive income attributable to noncontrolling interests	0	0	0
Comprehensive income attributable to Willis Group Holdings	($113)	($1,189)	$1,026

Recovered_Sheet3

Financial Information for Parent Issuer, Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Balance Sheet Disclosures) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Condensed Financial Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	$59	$0
CURRENT ASSETS
Cash and cash equivalents	635	796	500	436
Accounts receivable, net	1,044	1,041
Fiduciary assets	8,948	8,412
Deferred tax assets	12	15
Other current assets	214	197
Amounts owed by group undertakings	0	0
Total current assets	10,853	10,461
NON-CURRENT ASSETS
Investments in subsidiaries	0	0
Fixed assets, net	483	481
Goodwill	2,937	2,838	2,827
Other intangible assets, net	450	353
Investments in associates	169	176
Deferred tax assets	9	7
Pension benefits asset	314	278
Other non-current assets	220	206
Noncurrent amounts owed by group undertakings	0	0
Total non-current assets	4,582	4,339
TOTAL ASSETS	15,435	14,800
CURRENT LIABILITIES
Fiduciary liabilities	8,948	8,412
Deferred revenue and accrued expenses	619	586
Income taxes payable	33	21
Current portion of long-term debt	167	15
Deferred tax liabilities	21	25
Other current liabilities	444	415
Amounts due to group undertakings	0	0
Total current liabilities	10,232	9,474
NON-CURRENT LIABILITIES
Net liability investments in subsidiaries	0	0
Long-term debt	2,142	2,311
Liability for pension benefits	284	136
Deferred tax liabilities	128	56
Provisions for liabilities	194	206	180
Other non-current liabilities	389	374
Noncurrent amounts due to group undertakings	0	0
Total non-current liabilities	3,137	3,083
Total liabilities	13,369	12,557
EQUITY
Total of Willis Group Holdings shareholders' equity	1,985	2,215
Noncontrolling interests	22	28
Total equity	2,007	2,243
TOTAL LIABILITIES AND EQUITY	15,435	14,800
Willis Group Holdings — the Parent Issuer
Condensed Financial Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	0
CURRENT ASSETS
Cash and cash equivalents	9	3	1	0
Accounts receivable, net	0	0
Fiduciary assets	0	0
Deferred tax assets	0	0
Other current assets	1	1
Amounts owed by group undertakings	3,674	4,051
Total current assets	3,684	4,055
NON-CURRENT ASSETS
Investments in subsidiaries	0	0
Fixed assets, net	0	0
Goodwill	0	0
Other intangible assets, net	0	0
Investments in associates	0	0
Deferred tax assets	0	0
Pension benefits asset	0	0
Other non-current assets	3	4
Noncurrent amounts owed by group undertakings	0	0
Total non-current assets	3	4
TOTAL ASSETS	3,687	4,059
CURRENT LIABILITIES
Fiduciary liabilities	0	0
Deferred revenue and accrued expenses	1	2
Income taxes payable	0	0
Current portion of long-term debt	0	0
Deferred tax liabilities	0	0
Other current liabilities	67	62
Amounts due to group undertakings	0	0
Total current liabilities	68	64
NON-CURRENT LIABILITIES
Net liability investments in subsidiaries	838	985
Long-term debt	796	795
Liability for pension benefits	0	0
Deferred tax liabilities	0	0
Provisions for liabilities	0	0
Other non-current liabilities	0	0
Noncurrent amounts due to group undertakings	0	0
Total non-current liabilities	1,634	1,780
Total liabilities	1,702	1,844
EQUITY
Total of Willis Group Holdings shareholders' equity	1,985	2,215
Noncontrolling interests	0	0
Total equity	1,985	2,215
TOTAL LIABILITIES AND EQUITY	3,687	4,059
The Guarantors
Condensed Financial Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	0
CURRENT ASSETS
Cash and cash equivalents	2	3	0	163
Accounts receivable, net	4	4
Fiduciary assets	0	0
Deferred tax assets	0	0
Other current assets	37	31
Amounts owed by group undertakings	731	975
Total current assets	774	1,013
NON-CURRENT ASSETS
Investments in subsidiaries	3,528	3,788
Fixed assets, net	62	66
Goodwill	0	0
Other intangible assets, net	0	0
Investments in associates	147	156
Deferred tax assets	0	0
Pension benefits asset	0	0
Other non-current assets	10	14
Noncurrent amounts owed by group undertakings	740	690
Total non-current assets	4,487	4,714
TOTAL ASSETS	5,261	5,727
CURRENT LIABILITIES
Fiduciary liabilities	0	0
Deferred revenue and accrued expenses	34	29
Income taxes payable	7	3
Current portion of long-term debt	166	15
Deferred tax liabilities	0	0
Other current liabilities	57	53
Amounts due to group undertakings	4,623	5,177
Total current liabilities	4,887	5,277
NON-CURRENT LIABILITIES
Net liability investments in subsidiaries	0	0
Long-term debt	1,346	1,515
Liability for pension benefits	0	0
Deferred tax liabilities	0	1
Provisions for liabilities	0	0
Other non-current liabilities	17	48
Noncurrent amounts due to group undertakings	0	0
Total non-current liabilities	1,363	1,564
Total liabilities	6,250	6,841
EQUITY
Total of Willis Group Holdings shareholders' equity	-989	-1,114
Noncontrolling interests	0	0
Total equity	-989	-1,114
TOTAL LIABILITIES AND EQUITY	5,261	5,727
Other
Condensed Financial Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	59
CURRENT ASSETS
Cash and cash equivalents	624	790	499	273
Accounts receivable, net	1,040	1,037
Fiduciary assets	8,948	8,412
Deferred tax assets	12	16
Other current assets	205	186
Amounts owed by group undertakings	1,114	1,484
Total current assets	11,943	11,925
NON-CURRENT ASSETS
Investments in subsidiaries	0	0
Fixed assets, net	421	415
Goodwill	2,937	2,838
Other intangible assets, net	450	353
Investments in associates	22	20
Deferred tax assets	9	7
Pension benefits asset	314	278
Other non-current assets	207	188
Noncurrent amounts owed by group undertakings	0	0
Total non-current assets	4,360	4,099
TOTAL ASSETS	16,303	16,024
CURRENT LIABILITIES
Fiduciary liabilities	8,948	8,412
Deferred revenue and accrued expenses	584	555
Income taxes payable	55	39
Current portion of long-term debt	1	0
Deferred tax liabilities	21	25
Other current liabilities	320	300
Amounts due to group undertakings	896	1,333
Total current liabilities	10,825	10,664
NON-CURRENT LIABILITIES
Net liability investments in subsidiaries	0	0
Long-term debt	0	1
Liability for pension benefits	284	136
Deferred tax liabilities	128	55
Provisions for liabilities	194	206
Other non-current liabilities	372	326
Noncurrent amounts due to group undertakings	740	690
Total non-current liabilities	1,718	1,414
Total liabilities	12,543	12,078
EQUITY
Total of Willis Group Holdings shareholders' equity	3,679	3,918
Noncontrolling interests	22	28
Total equity	3,701	3,946
TOTAL LIABILITIES AND EQUITY	16,303	16,024
Consolidating adjustments
Condensed Financial Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	0
CURRENT ASSETS
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	0	0
Fiduciary assets	0	0
Deferred tax assets	0	-1
Other current assets	-29	-21
Amounts owed by group undertakings	-5,519	-6,510
Total current assets	-5,548	-6,532
NON-CURRENT ASSETS
Investments in subsidiaries	-3,528	-3,788
Fixed assets, net	0	0
Goodwill	0	0
Other intangible assets, net	0	0
Investments in associates	0	0
Deferred tax assets	0	0
Pension benefits asset	0	0
Other non-current assets	0	0
Noncurrent amounts owed by group undertakings	-740	-690
Total non-current assets	-4,268	-4,478
TOTAL ASSETS	-9,816	-11,010
CURRENT LIABILITIES
Fiduciary liabilities	0	0
Deferred revenue and accrued expenses	0	0
Income taxes payable	-29	-21
Current portion of long-term debt	0	0
Deferred tax liabilities	0	0
Other current liabilities	0	0
Amounts due to group undertakings	-5,519	-6,510
Total current liabilities	-5,548	-6,531
NON-CURRENT LIABILITIES
Net liability investments in subsidiaries	-838	-985
Long-term debt	0	0
Liability for pension benefits	0	0
Deferred tax liabilities	0	0
Provisions for liabilities	0	0
Other non-current liabilities	0	0
Noncurrent amounts due to group undertakings	-740	-690
Total non-current liabilities	-1,578	-1,675
Total liabilities	-7,126	-8,206
EQUITY
Total of Willis Group Holdings shareholders' equity	-2,690	-2,804
Noncontrolling interests	0	0
Total equity	-2,690	-2,804
TOTAL LIABILITIES AND EQUITY	($9,816)	($11,010)

Recovered_Sheet4

Financial Information for Parent Issuer, Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Cash Flow Disclosures) (Details) (USD $)	1 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2011	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Consolidating Statement of Cash Flows
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES		$477	$561	$525
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets		6	12	5
Additions to fixed assets		-113	-112	-135
Additions to intangible assets		-4	-7	-2
Acquisitions of operations, net of cash acquired		-241	-30	-33
Payments to acquire other investments, net of distributions received		-10	-7	-7
Proceeds from Sale of Equity Method Investments		0	4	0
Proceeds from Divestiture of Businesses, Net of Cash Divested		86	20	0
Cash received on intercompany investing activities		0	0	0
Cash paid on intercompany investing activities		0	0	0
Additional investment in subsidiaries		0
Net cash (used in) provided by continuing investing activities		-276	-120	-172
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued	800	0	522	0
Debt issuance costs		-3	-8	0
Repayments of debt		-15	-536	-15
Proceeds from issue of other debt		0	0	1
Payments of Debt Extinguishment Costs		0	-65	0
Repurchase of shares		-213	0	-100
Proceeds from issue of shares		134	155	53
Excess tax benefits from share-based payment arrangements		5	2	2
Dividends paid		-210	-193	-185
Proceeds from Noncontrolling Interests		0	0	3
Acquisition of noncontrolling interests		-4	-4	-39
Dividends paid to noncontrolling interests		-17	-10	-11
Cash received on intercompany financing activities		0	0	0
Cash paid on intercompany financing activities		0	0	0
Net cash provided by (used in) financing activities		-323	-137	-291
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS		-122	304	62
Effect of exchange rate changes on cash and cash equivalents		-39	-8	2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR		796	500	436
CASH AND CASH EQUIVALENTS, END OF YEAR		635	796	500
Willis Group Holdings — the Parent Issuer
Condensed Consolidating Statement of Cash Flows
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES		-35	4	-23
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets		0	0	0
Additions to fixed assets		0	0	0
Additions to intangible assets		0	0	0
Acquisitions of operations, net of cash acquired		0	0	0
Payments to acquire other investments, net of distributions received		0	0	0
Proceeds from Sale of Equity Method Investments			0
Proceeds from Divestiture of Businesses, Net of Cash Divested		0	0
Cash received on intercompany investing activities		361	383	256
Cash paid on intercompany investing activities		0	-347	0
Additional investment in subsidiaries		-31
Net cash (used in) provided by continuing investing activities		330	36	256
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued			0
Debt issuance costs		0	0
Repayments of debt		0	0	0
Proceeds from issue of other debt				0
Payments of Debt Extinguishment Costs			0
Repurchase of shares		-213		-100
Proceeds from issue of shares		134	155	53
Excess tax benefits from share-based payment arrangements		0	0	0
Dividends paid		-210	-193	-185
Proceeds from Noncontrolling Interests				0
Acquisition of noncontrolling interests		0	0	0
Dividends paid to noncontrolling interests		0	0	0
Cash received on intercompany financing activities		0	0	0
Cash paid on intercompany financing activities		0	0	0
Net cash provided by (used in) financing activities		-289	-38	-232
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS		6	2	1
Effect of exchange rate changes on cash and cash equivalents		0	0	0
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR		3	1	0
CASH AND CASH EQUIVALENTS, END OF YEAR		9	3	1
The Guarantors
Condensed Consolidating Statement of Cash Flows
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES		652	-98	1,460
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets		1	3	0
Additions to fixed assets		-19	-18	-26
Additions to intangible assets		0	0	0
Acquisitions of operations, net of cash acquired		0	-237	0
Payments to acquire other investments, net of distributions received		0	0	0
Proceeds from Divestiture of Businesses, Net of Cash Divested		0	0
Cash received on intercompany investing activities		120	223	150
Cash paid on intercompany investing activities		-180	-120	-328
Additional investment in subsidiaries		0
Net cash (used in) provided by continuing investing activities		-78	-149	-204
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued			522
Debt issuance costs		0	-8
Repayments of debt		-15	-536	-15
Proceeds from issue of other debt				1
Payments of Debt Extinguishment Costs			-65
Repurchase of shares		0		0
Proceeds from issue of shares		0	0	0
Excess tax benefits from share-based payment arrangements		0	0	0
Dividends paid		0	0	0
Proceeds from Noncontrolling Interests				0
Acquisition of noncontrolling interests		-4	0	0
Dividends paid to noncontrolling interests		0	0	0
Cash received on intercompany financing activities		46	780	81
Cash paid on intercompany financing activities		-602	-443	-1,486
Net cash provided by (used in) financing activities		-575	250	-1,419
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS		-1	3	-163
Effect of exchange rate changes on cash and cash equivalents		0	0	0
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR		3	0	163
CASH AND CASH EQUIVALENTS, END OF YEAR		2	3	0
Other
Condensed Consolidating Statement of Cash Flows
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES		212	662	-97
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets		6	9	5
Additions to fixed assets		-95	-94	-109
Additions to intangible assets		-4	-7	-2
Acquisitions of operations, net of cash acquired		-241	-30	-33
Payments to acquire other investments, net of distributions received		-10	-7	-7
Proceeds from Sale of Equity Method Investments			4
Proceeds from Divestiture of Businesses, Net of Cash Divested		86	257
Cash received on intercompany investing activities		435	60	1,230
Cash paid on intercompany investing activities		-46	-780	-81
Additional investment in subsidiaries		0
Net cash (used in) provided by continuing investing activities		131	-588	1,003
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued			0
Debt issuance costs		-3	0
Repayments of debt		0	0	0
Proceeds from issue of other debt				0
Payments of Debt Extinguishment Costs			0
Repurchase of shares		0		0
Proceeds from issue of shares		31	0	0
Excess tax benefits from share-based payment arrangements		5	2	2
Dividends paid		-352	-7	-815
Proceeds from Noncontrolling Interests				3
Acquisition of noncontrolling interests		0	-4	-39
Dividends paid to noncontrolling interests		-17	-10	-11
Cash received on intercompany financing activities		180	467	328
Cash paid on intercompany financing activities		-314	-223	-150
Net cash provided by (used in) financing activities		-470	225	-682
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS		-127	299	224
Effect of exchange rate changes on cash and cash equivalents		-39	-8	2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR		790	499	273
CASH AND CASH EQUIVALENTS, END OF YEAR		624	790	499
Consolidating adjustments
Condensed Consolidating Statement of Cash Flows
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES		-352	-7	-815
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds on disposal of fixed and intangible assets		-1	0	0
Additions to fixed assets		1	0	0
Additions to intangible assets		0	0	0
Acquisitions of operations, net of cash acquired		0	237	0
Payments to acquire other investments, net of distributions received		0	0	0
Proceeds from Divestiture of Businesses, Net of Cash Divested		0	-237
Cash received on intercompany investing activities		-916	-666	-1,636
Cash paid on intercompany investing activities		226	1,247	409
Additional investment in subsidiaries		31
Net cash (used in) provided by continuing investing activities		-659	581	-1,227
CASH FLOWS FROM FINANCING ACTIVITIES
Senior notes issued			0
Debt issuance costs		0	0
Repayments of debt		0	0	0
Proceeds from issue of other debt				0
Payments of Debt Extinguishment Costs			0
Repurchase of shares		0		0
Proceeds from issue of shares		-31	0	0
Excess tax benefits from share-based payment arrangements		0	0	0
Dividends paid		352	7	815
Proceeds from Noncontrolling Interests				0
Acquisition of noncontrolling interests		0	0	0
Dividends paid to noncontrolling interests		0	0	0
Cash received on intercompany financing activities		-226	-1,247	-409
Cash paid on intercompany financing activities		916	666	1,636
Net cash provided by (used in) financing activities		1,011	-574	2,042
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS		0	0	0
Effect of exchange rate changes on cash and cash equivalents		0	0	0
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR		0	0	0
CASH AND CASH EQUIVALENTS, END OF YEAR		$0	$0	$0

Recovered_Sheet5

Financial Information for Parent Issuer, Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Details Textual) (USD $)	1 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2011	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financial Information for Parent Issuer Guarantor Subsidiaries and Non-Guarantor Subsidiaries Disclosure [Abstract]
Senior notes issued	$800	$0	$522	$0
Percentage of ownership in wholly on subsidiary by parent		100.00%

Financial_Information_for_Issu2

Financial Information for Issuer, Parent Guarantor, Other Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Income Statement Disclosures) (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Commissions and fees									$3,767	$3,633	$3,458
Gross Investment Income, Operating									16	15	18
Other income									19	7	4
Total Revenues	958	812	935	1,097	919	795	890	1,051	3,802	3,655	3,480
Salaries and benefits									-2,314	-2,207	-2,475
Other operating expenses									-659	-636	-600
Depreciation expense									-92	-94	-79
Amortization of intangible assets									-54	-55	-59
Restructuring Costs									-36	0	0
Goodwill impairment charge									0	0	-492
Total expenses	-819	-778	-787	-771	-774	-725	-723	-770	-3,155	-2,992	-3,705
OPERATING (LOSS) INCOME									647	663	-225
Other Nonoperating Income (Expense)									6	22	16
Income from group undertakings									0	0	0
Expenses due to group undertakings									0	0	0
Loss on extinguishment of debt									0	-60	0
Interest expense									-135	-126	-128
Income (loss) before income taxes and interest in earnings of associates									518	499	-337
Income taxes									-159	-122	-101
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									359	377	-438
Interest in earnings of associates, net of tax									14	0	5
EQUITY ACCOUNT FOR SUBSIDIARIES									0	0	0
Net income (loss)	83	-8	48	250	74	-27	107	223	373	377	-433
Net Income (Loss) Attributable to Noncontrolling Interest									-11	-12	-13
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS	76	-7	47	246	68	-27	105	219	362	365	-446
Willis Group Holdings — the Parent Issuer
Condensed Financial Statements, Captions [Line Items]
Commissions and fees									0	0	0
Gross Investment Income, Operating									0	0	0
Other income									0	0	0
Total Revenues									0	0	0
Salaries and benefits									-1	-1	-2
Other operating expenses									-16	-5	-6
Depreciation expense									0	0	0
Amortization of intangible assets									0	0	0
Restructuring Costs									0
Goodwill impairment charge											0
Total expenses									-17	-6	-8
OPERATING (LOSS) INCOME									-17	-6	-8
Other Nonoperating Income (Expense)									-15	5	2
Income from group undertakings									0	0	0
Expenses due to group undertakings									0	-10	0
Loss on extinguishment of debt										0
Interest expense									-43	-42	-43
Income (loss) before income taxes and interest in earnings of associates									-75	-53	-49
Income taxes									0	0	0
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									-75	-53	-49
Interest in earnings of associates, net of tax									0	0	0
EQUITY ACCOUNT FOR SUBSIDIARIES									437	418	-397
Net income (loss)									362	365	-446
Net Income (Loss) Attributable to Noncontrolling Interest									0	0	0
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS									362	365	-446
Guarantor Companies [Member]
Condensed Financial Statements, Captions [Line Items]
Commissions and fees									8	8	0
Gross Investment Income, Operating									0	0	1
Other income									0	0	0
Total Revenues									8	8	1
Salaries and benefits									-81	-103	-96
Other operating expenses									-133	-231	-158
Depreciation expense									-21	-23	-16
Amortization of intangible assets									0	0	0
Restructuring Costs									-14
Goodwill impairment charge											0
Total expenses									-249	-357	-270
OPERATING (LOSS) INCOME									-241	-349	-269
Other Nonoperating Income (Expense)									-220	-4	-4
Income from group undertakings									450	491	436
Expenses due to group undertakings									-190	-153	-185
Loss on extinguishment of debt										-60
Interest expense									-44	-61	-69
Income (loss) before income taxes and interest in earnings of associates									-245	-136	-91
Income taxes									54	29	76
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									-191	-107	-15
Interest in earnings of associates, net of tax									10	9	8
EQUITY ACCOUNT FOR SUBSIDIARIES									609	515	-390
Net income (loss)									428	417	-397
Net Income (Loss) Attributable to Noncontrolling Interest									0	0	0
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS									428	417	-397
Trinity Acquisition Limited [Member]
Condensed Financial Statements, Captions [Line Items]
Commissions and fees									0	0	0
Gross Investment Income, Operating									0	0	0
Other income									0	0	0
Total Revenues									0	0	0
Salaries and benefits									0	0	0
Other operating expenses									0	-1	0
Depreciation expense									0	0	0
Amortization of intangible assets									0	0	0
Restructuring Costs									0
Goodwill impairment charge											0
Total expenses									0	-1	0
OPERATING (LOSS) INCOME									0	-1	0
Other Nonoperating Income (Expense)									0	0	1
Income from group undertakings									91	68	79
Expenses due to group undertakings									-29	-26	-27
Loss on extinguishment of debt										0
Interest expense									-36	-18	-8
Income (loss) before income taxes and interest in earnings of associates									26	23	45
Income taxes									-5	-6	-11
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									21	17	34
Interest in earnings of associates, net of tax									0	0	0
EQUITY ACCOUNT FOR SUBSIDIARIES									314	344	-461
Net income (loss)									335	361	-427
Net Income (Loss) Attributable to Noncontrolling Interest									0	0	0
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS									335	361	-427
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Commissions and fees									3,759	3,625	3,458
Gross Investment Income, Operating									16	15	17
Other income									19	7	4
Total Revenues									3,794	3,647	3,479
Salaries and benefits									-2,232	-2,103	-2,377
Other operating expenses									-510	-399	-436
Depreciation expense									-71	-71	-63
Amortization of intangible assets									-54	-55	-59
Restructuring Costs									-22
Goodwill impairment charge											-492
Total expenses									-2,889	-2,628	-3,427
OPERATING (LOSS) INCOME									905	1,019	52
Other Nonoperating Income (Expense)									11	31	17
Income from group undertakings									102	86	111
Expenses due to group undertakings									-424	-456	-414
Loss on extinguishment of debt										0
Interest expense									-12	-5	-8
Income (loss) before income taxes and interest in earnings of associates									582	675	-242
Income taxes									-208	-145	-166
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									374	530	-408
Interest in earnings of associates, net of tax									4	-9	-3
EQUITY ACCOUNT FOR SUBSIDIARIES									0	0	0
Net income (loss)									378	521	-411
Net Income (Loss) Attributable to Noncontrolling Interest									-11	-12	-13
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS									367	509	-424
Consolidation entries [Member]
Condensed Financial Statements, Captions [Line Items]
Commissions and fees									0	0	0
Gross Investment Income, Operating									0	0	0
Other income									0	0	0
Total Revenues									0	0	0
Salaries and benefits									0	0	0
Other operating expenses									0	0	0
Depreciation expense									0	0	0
Amortization of intangible assets									0	0	0
Restructuring Costs									0
Goodwill impairment charge											0
Total expenses									0	0	0
OPERATING (LOSS) INCOME									0	0	0
Other Nonoperating Income (Expense)									230	-10	0
Income from group undertakings									-643	-645	-626
Expenses due to group undertakings									643	645	626
Loss on extinguishment of debt										0
Interest expense									0	0	0
Income (loss) before income taxes and interest in earnings of associates									230	-10	0
Income taxes									0	0	0
(LOSS) INCOME FROM CONTINUING OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES									230	-10	0
Interest in earnings of associates, net of tax									0	0	0
EQUITY ACCOUNT FOR SUBSIDIARIES									-1,360	-1,277	1,248
Net income (loss)									-1,130	-1,287	1,248
Net Income (Loss) Attributable to Noncontrolling Interest									0	0	0
NET INCOME ATTRIBUTABLE TO WILLIS GROUP HOLDINGS									($1,130)	($1,287)	$1,248

Financial_Information_for_Issu3

Financial Information for Issuer, Parent Guarantor, Other Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Comprehensive Income Disclosures) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	($6)	$534	($539)
Less: Comprehensive income attributable to noncontrolling interests	-5	-12	-13
Comprehensive income attributable to Willis Group Holdings	-11	522	-552
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	-11	522	-552
Less: Comprehensive income attributable to noncontrolling interests	0	0	0
Comprehensive income attributable to Willis Group Holdings	-11	522	-552
Guarantor Companies [Member]
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	69	565	-494
Less: Comprehensive income attributable to noncontrolling interests	0	0	0
Comprehensive income attributable to Willis Group Holdings	69	565	-494
Trinity Acquisition Limited [Member]
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	-5	504	-528
Less: Comprehensive income attributable to noncontrolling interests	0	0	0
Comprehensive income attributable to Willis Group Holdings	-5	504	-528
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	49	636	-519
Less: Comprehensive income attributable to noncontrolling interests	-5	-12	-13
Comprehensive income attributable to Willis Group Holdings	44	624	-532
Consolidation entries [Member]
Condensed Financial Statements, Captions [Line Items]
Comprehensive (loss) income	-108	-1,693	1,554
Less: Comprehensive income attributable to noncontrolling interests	0	0	0
Comprehensive income attributable to Willis Group Holdings	($108)	($1,693)	$1,554

Financial_Information_for_Issu4

Financial Information for Issuer, Parent Guarantor, Other Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Balance Sheet) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Condensed Balance Sheet Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	$59	$0
Cash and cash equivalents	635	796	500	436
Accounts receivable, net	1,044	1,041
Fiduciary assets	8,948	8,412
Deferred tax assets	12	15
Other current assets	214	197
Amounts owed by group undertakings	0	0
Total current assets	10,853	10,461
Investments in subsidiaries	0	0
Fixed assets, net	483	481
Goodwill	2,937	2,838	2,827
Other intangible assets, net	450	353
Investments in associates	169	176
Deferred tax assets	9	7
Pension benefits asset	314	278
Other non-current assets	220	206
Noncurrent amounts owed by group undertakings	0	0
Total non-current assets	4,582	4,339
TOTAL ASSETS	15,435	14,800
Fiduciary liabilities	8,948	8,412
Deferred revenue and accrued expenses	619	586
Income taxes payable	33	21
Current portion of long-term debt	167	15
Deferred tax liabilities	21	25
Other current liabilities	444	415
Amounts due to group undertakings	0	0
Total current liabilities	10,232	9,474
Net liability investments in subsidiaries	0	0
Long-term debt	2,142	2,311
Liability for pension benefits	284	136
Deferred tax liabilities	128	56
Provisions for liabilities	194	206	180
Other non-current liabilities	389	374
Noncurrent amounts due to group undertakings	0	0
Total non-current liabilities	3,137	3,083
Total liabilities	13,369	12,557
Total Willis Group Holdings shareholders' equity	1,985	2,215
Noncontrolling interests	22	28
Total equity	2,007	2,243
TOTAL LIABILITIES AND EQUITY	15,435	14,800
Non-Guarantor Subsidiaries [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	59
Cash and cash equivalents	624	790	499	273
Accounts receivable, net	1,040	1,037
Fiduciary assets	8,948	8,412
Deferred tax assets	12	16
Other current assets	205	186
Amounts owed by group undertakings	1,114	1,484
Total current assets	11,943	11,925
Investments in subsidiaries	0	0
Fixed assets, net	421	415
Goodwill	2,937	2,838
Other intangible assets, net	450	353
Investments in associates	22	20
Deferred tax assets	9	7
Pension benefits asset	314	278
Other non-current assets	207	188
Noncurrent amounts owed by group undertakings	0	0
Total non-current assets	4,360	4,099
TOTAL ASSETS	16,303	16,024
Fiduciary liabilities	8,948	8,412
Deferred revenue and accrued expenses	584	555
Income taxes payable	55	39
Current portion of long-term debt	1	0
Deferred tax liabilities	21	25
Other current liabilities	320	300
Amounts due to group undertakings	896	1,333
Total current liabilities	10,825	10,664
Net liability investments in subsidiaries	0	0
Long-term debt	0	1
Liability for pension benefits	284	136
Deferred tax liabilities	128	55
Provisions for liabilities	194	206
Other non-current liabilities	372	326
Noncurrent amounts due to group undertakings	740	690
Total non-current liabilities	1,718	1,414
Total liabilities	12,543	12,078
Total Willis Group Holdings shareholders' equity	3,679	3,918
Noncontrolling interests	22	28
Total equity	3,701	3,946
TOTAL LIABILITIES AND EQUITY	16,303	16,024
Consolidating adjustments
Condensed Balance Sheet Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	0
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	0	0
Fiduciary assets	0	0
Deferred tax assets	0	-1
Other current assets	-29	-21
Amounts owed by group undertakings	-5,519	-6,510
Total current assets	-5,548	-6,532
Investments in subsidiaries	-3,528	-3,788
Fixed assets, net	0	0
Goodwill	0	0
Other intangible assets, net	0	0
Investments in associates	0	0
Deferred tax assets	0	0
Pension benefits asset	0	0
Other non-current assets	0	0
Noncurrent amounts owed by group undertakings	-740	-690
Total non-current assets	-4,268	-4,478
TOTAL ASSETS	-9,816	-11,010
Fiduciary liabilities	0	0
Deferred revenue and accrued expenses	0	0
Income taxes payable	-29	-21
Current portion of long-term debt	0	0
Deferred tax liabilities	0	0
Other current liabilities	0	0
Amounts due to group undertakings	-5,519	-6,510
Total current liabilities	-5,548	-6,531
Net liability investments in subsidiaries	-838	-985
Long-term debt	0	0
Liability for pension benefits	0	0
Deferred tax liabilities	0	0
Provisions for liabilities	0	0
Other non-current liabilities	0	0
Noncurrent amounts due to group undertakings	-740	-690
Total non-current liabilities	-1,578	-1,675
Total liabilities	-7,126	-8,206
Total Willis Group Holdings shareholders' equity	-2,690	-2,804
Noncontrolling interests	0	0
Total equity	-2,690	-2,804
TOTAL LIABILITIES AND EQUITY	-9,816	-11,010
Consolidation entries [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	0
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	0	0
Fiduciary assets	0	0
Deferred tax assets	0	-1
Other current assets	-34	-27
Amounts owed by group undertakings	-6,739	-7,303
Total current assets	-6,773	-7,331
Investments in subsidiaries	-6,056	-6,421
Fixed assets, net	0	0
Goodwill	0	0
Other intangible assets, net	0	0
Investments in associates	0	0
Deferred tax assets	0	0
Pension benefits asset	0	0
Other non-current assets	0	0
Noncurrent amounts owed by group undertakings	-1,258	-1,631
Total non-current assets	-7,314	-8,052
TOTAL ASSETS	-14,087	-15,383
Fiduciary liabilities	0	0
Deferred revenue and accrued expenses	0	0
Income taxes payable	-34	-27
Current portion of long-term debt	0	0
Deferred tax liabilities	0	0
Other current liabilities	0	0
Amounts due to group undertakings	-6,739	-7,303
Total current liabilities	-6,773	-7,330
Net liability investments in subsidiaries	-838	-985
Long-term debt	0	0
Liability for pension benefits	0	0
Deferred tax liabilities	0	0
Provisions for liabilities	0	0
Other non-current liabilities	0	0
Noncurrent amounts due to group undertakings	-1,258	-1,631
Total non-current liabilities	-2,096	-2,616
Total liabilities	-8,869	-9,946
Total Willis Group Holdings shareholders' equity	-5,218	-5,437
Noncontrolling interests	0	0
Total equity	-5,218	-5,437
TOTAL LIABILITIES AND EQUITY	-14,087	-15,383
Willis Group Holdings — the Parent Issuer
Condensed Balance Sheet Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	0
Cash and cash equivalents	9	3	1	0
Accounts receivable, net	0	0
Fiduciary assets	0	0
Deferred tax assets	0	0
Other current assets	1	1
Amounts owed by group undertakings	3,674	4,051
Total current assets	3,684	4,055
Investments in subsidiaries	0	0
Fixed assets, net	0	0
Goodwill	0	0
Other intangible assets, net	0	0
Investments in associates	0	0
Deferred tax assets	0	0
Pension benefits asset	0	0
Other non-current assets	3	4
Noncurrent amounts owed by group undertakings	0	0
Total non-current assets	3	4
TOTAL ASSETS	3,687	4,059
Fiduciary liabilities	0	0
Deferred revenue and accrued expenses	1	2
Income taxes payable	0	0
Current portion of long-term debt	0	0
Deferred tax liabilities	0	0
Other current liabilities	67	62
Amounts due to group undertakings	0	0
Total current liabilities	68	64
Net liability investments in subsidiaries	838	985
Long-term debt	796	795
Liability for pension benefits	0	0
Deferred tax liabilities	0	0
Provisions for liabilities	0	0
Other non-current liabilities	0	0
Noncurrent amounts due to group undertakings	0	0
Total non-current liabilities	1,634	1,780
Total liabilities	1,702	1,844
Total Willis Group Holdings shareholders' equity	1,985	2,215
Noncontrolling interests	0	0
Total equity	1,985	2,215
TOTAL LIABILITIES AND EQUITY	3,687	4,059
Guarantor Companies [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	0
Cash and cash equivalents	2	3	0	163
Accounts receivable, net	4	4
Fiduciary assets	0	0
Deferred tax assets	0	0
Other current assets	41	36
Amounts owed by group undertakings	1,154	975
Total current assets	1,201	1,018
Investments in subsidiaries	3,478	3,716
Fixed assets, net	62	66
Goodwill	0	0
Other intangible assets, net	0	0
Investments in associates	147	156
Deferred tax assets	0	0
Pension benefits asset	0	0
Other non-current assets	2	5
Noncurrent amounts owed by group undertakings	740	1,113
Total non-current assets	4,429	5,056
TOTAL ASSETS	5,630	6,074
Fiduciary liabilities	0	0
Deferred revenue and accrued expenses	34	29
Income taxes payable	7	4
Current portion of long-term debt	149	0
Deferred tax liabilities	0	0
Other current liabilities	46	42
Amounts due to group undertakings	5,267	5,813
Total current liabilities	5,503	5,888
Net liability investments in subsidiaries	0	0
Long-term debt	581	733
Liability for pension benefits	0	0
Deferred tax liabilities	0	1
Provisions for liabilities	0	0
Other non-current liabilities	17	48
Noncurrent amounts due to group undertakings	518	518
Total non-current liabilities	1,116	1,300
Total liabilities	6,619	7,188
Total Willis Group Holdings shareholders' equity	-989	-1,114
Noncontrolling interests	0	0
Total equity	-989	-1,114
TOTAL LIABILITIES AND EQUITY	5,630	6,074
Trinity Acquisition Limited [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	0
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	0	0
Fiduciary assets	0	0
Deferred tax assets	0	0
Other current assets	1	1
Amounts owed by group undertakings	797	793
Total current assets	798	794
Investments in subsidiaries	2,578	2,705
Fixed assets, net	0	0
Goodwill	0	0
Other intangible assets, net	0	0
Investments in associates	0	0
Deferred tax assets	0	0
Pension benefits asset	0	0
Other non-current assets	8	9
Noncurrent amounts owed by group undertakings	518	518
Total non-current assets	3,104	3,232
TOTAL ASSETS	3,902	4,026
Fiduciary liabilities	0	0
Deferred revenue and accrued expenses	0	0
Income taxes payable	5	5
Current portion of long-term debt	17	15
Deferred tax liabilities	0	0
Other current liabilities	11	11
Amounts due to group undertakings	576	157
Total current liabilities	609	188
Net liability investments in subsidiaries	0	0
Long-term debt	765	782
Liability for pension benefits	0	0
Deferred tax liabilities	0	0
Provisions for liabilities	0	0
Other non-current liabilities	0	0
Noncurrent amounts due to group undertakings	0	423
Total non-current liabilities	765	1,205
Total liabilities	1,374	1,393
Total Willis Group Holdings shareholders' equity	2,528	2,633
Noncontrolling interests	0	0
Total equity	2,528	2,633
TOTAL LIABILITIES AND EQUITY	$3,902	$4,026

Financial_Information_for_Issu5

Financial Information for Issuer, Parent Guarantor, Other Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Cash Flow Statement) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Cash Flow Statements, Captions [Line Items]
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES	$477	$561	$525
Proceeds on disposal of fixed and intangible assets	6	12	5
Additions to fixed assets	-113	-112	-135
Additions to intangible assets	-4	-7	-2
Acquisitions of operations, net of cash acquired	-241	-30	-33
Payments to acquire other investments, net of distributions received	-10	-7	-7
Proceeds from Sale of Equity Method Investments	0	4	0
Proceeds from Divestiture of Businesses, Net of Cash Divested	86	20	0
Cash received on intercompany investing activities	0	0	0
Cash paid on intercompany investing activities	0	0	0
Additional investment in subsidiaries	0
Net cash (used in) provided by continuing investing activities	-276	-120	-172
Senior notes issued	0	522	0
Debt issuance costs	-3	-8	0
Repayments of debt	-15	-536	-15
Payments of Debt Extinguishment Costs	0	-65	0
Proceeds from issue of other debt	0	0	1
Repurchase of shares	-213	0	-100
Proceeds from issue of shares	134	155	53
Excess tax benefits from share-based payment arrangements	5	2	2
Dividends paid	-210	-193	-185
Proceeds from Noncontrolling Interests	0	0	3
Acquisition of noncontrolling interests	-4	-4	-39
Dividends paid to noncontrolling interests	-17	-10	-11
Cash received on intercompany financing activities	0	0	0
Cash paid on intercompany financing activities	0	0	0
Net cash provided by (used in) financing activities	-323	-137	-291
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	-122	304	62
Effect of exchange rate changes on cash and cash equivalents	-39	-8	2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	796	500	436
CASH AND CASH EQUIVALENTS, END OF YEAR	635	796	500
Parent Company [Member]
Condensed Cash Flow Statements, Captions [Line Items]
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES	-35	4	-23
Proceeds on disposal of fixed and intangible assets	0	0	0
Additions to fixed assets	0	0	0
Additions to intangible assets	0	0	0
Acquisitions of operations, net of cash acquired	0	0	0
Payments to acquire other investments, net of distributions received	0	0	0
Proceeds from Sale of Equity Method Investments		0
Proceeds from Divestiture of Businesses, Net of Cash Divested	0	0
Cash received on intercompany investing activities	361	383	256
Cash paid on intercompany investing activities	0	-347	0
Additional investment in subsidiaries	-31
Net cash (used in) provided by continuing investing activities	330	36	256
Senior notes issued		0
Debt issuance costs	0	0
Repayments of debt	0	0	0
Payments of Debt Extinguishment Costs		0
Proceeds from issue of other debt			0
Repurchase of shares	-213		-100
Proceeds from issue of shares	134	155	53
Excess tax benefits from share-based payment arrangements	0	0	0
Dividends paid	-210	-193	-185
Proceeds from Noncontrolling Interests			0
Acquisition of noncontrolling interests	0	0	0
Dividends paid to noncontrolling interests	0	0	0
Cash received on intercompany financing activities	0	0	0
Cash paid on intercompany financing activities	0	0	0
Net cash provided by (used in) financing activities	-289	-38	-232
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	6	2	1
Effect of exchange rate changes on cash and cash equivalents	0	0	0
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3	1	0
CASH AND CASH EQUIVALENTS, END OF YEAR	9	3	1
Guarantor Companies [Member]
Condensed Cash Flow Statements, Captions [Line Items]
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES	781	399	2,393
Proceeds on disposal of fixed and intangible assets	1	3	0
Additions to fixed assets	-19	-18	-26
Additions to intangible assets	0	0	0
Acquisitions of operations, net of cash acquired	0	-237	0
Payments to acquire other investments, net of distributions received	0	0	0
Proceeds from Divestiture of Businesses, Net of Cash Divested	0	0
Cash received on intercompany investing activities	120	160	176
Cash paid on intercompany investing activities	-180	-120	-197
Additional investment in subsidiaries	0
Net cash (used in) provided by continuing investing activities	-78	-212	-47
Senior notes issued		0
Debt issuance costs	0	0
Repayments of debt	0	-521	-4
Payments of Debt Extinguishment Costs		-65
Proceeds from issue of other debt			0
Repurchase of shares			0
Proceeds from issue of shares	0	0	0
Excess tax benefits from share-based payment arrangements	0	0	0
Dividends paid	-155	-230	-1,220
Proceeds from Noncontrolling Interests			0
Acquisition of noncontrolling interests	-4	0	0
Dividends paid to noncontrolling interests	0	0	0
Cash received on intercompany financing activities	50	1,075	81
Cash paid on intercompany financing activities	-595	-443	-1,366
Net cash provided by (used in) financing activities	-704	-184	-2,509
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	-1	3	-163
Effect of exchange rate changes on cash and cash equivalents	0	0	0
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	3	0	163
CASH AND CASH EQUIVALENTS, END OF YEAR	2	3	0
Trinity Acquisition Limited [Member]
Condensed Cash Flow Statements, Captions [Line Items]
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES	181	63	1,356
Proceeds on disposal of fixed and intangible assets	0	0	0
Additions to fixed assets	0	0	0
Additions to intangible assets	0	0	0
Acquisitions of operations, net of cash acquired	0	0	0
Payments to acquire other investments, net of distributions received	0	0	0
Proceeds from Sale of Equity Method Investments		0
Proceeds from Divestiture of Businesses, Net of Cash Divested	0	0
Cash received on intercompany investing activities	0	132	78
Cash paid on intercompany investing activities	-4	-442	-131
Additional investment in subsidiaries	0
Net cash (used in) provided by continuing investing activities	-4	-310	-53
Senior notes issued		522
Debt issuance costs	0	-8
Repayments of debt	-15	-15	-11
Payments of Debt Extinguishment Costs		0
Proceeds from issue of other debt			1
Repurchase of shares			0
Proceeds from issue of shares	0	0	0
Excess tax benefits from share-based payment arrangements	0	0	0
Dividends paid	-155	-330	-1,069
Proceeds from Noncontrolling Interests			0
Acquisition of noncontrolling interests	0	0	0
Dividends paid to noncontrolling interests	0	0	0
Cash received on intercompany financing activities	0	147	0
Cash paid on intercompany financing activities	-7	-69	-224
Net cash provided by (used in) financing activities	-177	247	-1,303
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	0	0	0
Effect of exchange rate changes on cash and cash equivalents	0	0	0
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	0	0	0
CASH AND CASH EQUIVALENTS, END OF YEAR	0	0	0
Non-Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES	212	662	-97
Proceeds on disposal of fixed and intangible assets	6	9	5
Additions to fixed assets	-95	-94	-109
Additions to intangible assets	-4	-7	-2
Acquisitions of operations, net of cash acquired	-241	-30	-33
Payments to acquire other investments, net of distributions received	-10	-7	-7
Proceeds from Sale of Equity Method Investments		4
Proceeds from Divestiture of Businesses, Net of Cash Divested	86	257
Cash received on intercompany investing activities	435	60	1,230
Cash paid on intercompany investing activities	-46	-780	-81
Additional investment in subsidiaries	0
Net cash (used in) provided by continuing investing activities	131	-588	1,003
Senior notes issued		0
Debt issuance costs	-3	0
Repayments of debt	0	0	0
Payments of Debt Extinguishment Costs		0
Proceeds from issue of other debt			0
Repurchase of shares	0		0
Proceeds from issue of shares	31	0	0
Excess tax benefits from share-based payment arrangements	5	2	2
Dividends paid	-352	-7	-815
Proceeds from Noncontrolling Interests			3
Acquisition of noncontrolling interests	0	-4	-39
Dividends paid to noncontrolling interests	-17	-10	-11
Cash received on intercompany financing activities	180	467	328
Cash paid on intercompany financing activities	-314	-223	-150
Net cash provided by (used in) financing activities	-470	225	-682
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	-127	299	224
Effect of exchange rate changes on cash and cash equivalents	-39	-8	2
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	790	499	273
CASH AND CASH EQUIVALENTS, END OF YEAR	624	790	499
Consolidation entries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
NET CASH (USED BY) PROVIDED BY OPERATING ACTIVITIES	-662	-567	-3,104
Proceeds on disposal of fixed and intangible assets	-1	0	0
Additions to fixed assets	1	0	0
Additions to intangible assets	0	0	0
Acquisitions of operations, net of cash acquired	0	237	0
Payments to acquire other investments, net of distributions received	0	0	0
Proceeds from Sale of Equity Method Investments		0
Proceeds from Divestiture of Businesses, Net of Cash Divested	0	-237
Cash received on intercompany investing activities	-916	-735	-1,740
Cash paid on intercompany investing activities	230	1,689	409
Additional investment in subsidiaries	31
Net cash (used in) provided by continuing investing activities	-655	954	-1,331
Senior notes issued		0
Debt issuance costs	0	0
Repayments of debt	0	0	0
Payments of Debt Extinguishment Costs		0
Proceeds from issue of other debt			0
Repurchase of shares			0
Proceeds from issue of shares	-31	0	0
Excess tax benefits from share-based payment arrangements	0	0	0
Dividends paid	662	567	3,104
Proceeds from Noncontrolling Interests			0
Acquisition of noncontrolling interests	0	0	0
Dividends paid to noncontrolling interests	0	0	0
Cash received on intercompany financing activities	-230	-1,689	-409
Cash paid on intercompany financing activities	916	735	1,740
Net cash provided by (used in) financing activities	1,317	-387	4,435
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	0	0	0
Effect of exchange rate changes on cash and cash equivalents	0	0	0
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	0	0	0
CASH AND CASH EQUIVALENTS, END OF YEAR	$0	$0	$0

Financial_Information_for_Issu6

Financial Information for Issuer, Parent Guarantor, Other Guarantor Subsidiaries and Non-Guarantor Subsidiaries (Details Textual) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Aug. 15, 2013
Condensed Financial Statements, Captions [Line Items]
Percentage of Ownership in Wholly on Subsidiary by Parent	100.00%
Trinity Acquisition Limited [Member]
Condensed Financial Statements, Captions [Line Items]
Senior notes, outstanding balance		$525

Quarterly_Financial_Data_Unaud2

Quarterly Financial Data (Unaudited) (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Quarterly Financial Data [Abstract]
Total Revenues	$958	$812	$935	$1,097	$919	$795	$890	$1,051	$3,802	$3,655	$3,480
Total expenses	-819	-778	-787	-771	-774	-725	-723	-770	-3,155	-2,992	-3,705
Net income (loss)	83	-8	48	250	74	-27	107	223	373	377	-433
Net Income (Loss) Attributable to Parent	$76	($7)	$47	$246	$68	($27)	$105	$219	$362	$365	($446)
Earnings per share - continuing operations
Basic	$0.43	($0.04)	$0.26	$1.37	$0.38	($0.15)	$0.60	$1.27	$2.03	$2.07	($2.58)
Diluted	$0.42	($0.04)	$0.26	$1.35	$0.37	($0.15)	$0.59	$1.24	$2	$2.04	($2.58)