Validus 8-K 2 Apr 15 2014 FY Other Events Financial data

Document_and_Entity_Informatio

Document and Entity Information	12 Months Ended
	Dec. 31, 2014
Document and Entity Information [Abstract]
Entity Registrant Name	VALIDUS HOLDINGS LTD
Entity Central Index Key	1348259
Document Type	8-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

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Assets
Fixed maturities, at fair value (amortized cost: 2014—$5,534,494; 2013—$5,522,853)	$5,532,731	$5,542,258
Short-term investments, at fair value (amortized cost: 2014—$1,051,222; 2013—$787,670)	1,051,074	787,714
Other investments, at fair value (cost: 2014—$879,176; 2013—$723,498)	813,011	704,086
Cash and cash equivalents	577,240	734,148
Restricted cash	173,003	200,492
Total investments and cash	8,147,059	7,968,698
Investments in affiliates	261,483	141,243
Premiums receivable	707,647	697,233
Deferred acquisition costs	161,295	134,269
Prepaid reinsurance premiums	81,983	103,251
Securities lending collateral	470	3,392
Loss reserves recoverable	377,466	370,154
Paid losses recoverable	38,078	80,080
Deferred tax asset	23,821	0
Intangible assets	126,924	106,407
Goodwill	195,897	20,393
Accrued investment income	24,865	18,876
Other assets	164,633	202,436
Total assets	10,311,621	9,846,432
Liabilities
Reserve for losses and loss expenses	3,234,394	3,030,399
Unearned premiums	990,564	824,496
Reinsurance balances payable	127,128	154,874
Securities lending payable	936	3,858
Deferred tax liability	5,541	19,086
Net payable for investments purchased	50,256	19,383
Accounts payable and accrued expenses	318,245	278,187
Notes payable to operating affiliates	671,465	439,272
Senior notes payable	247,306	247,198
Debentures payable	539,277	541,416
Total liabilities	6,185,112	5,558,169
Commitments and contingent liabilities
Redeemable noncontrolling interest	79,956	86,512
Shareholders' equity
Common shares, 571,428,571 authorized, par value $0.175 (Issued: 2014—155,554,224; 2013—154,488,497; Outstanding: 2014—83,869,845; 2013—96,044,312)	27,222	27,036
Treasury shares (2014—71,684,379; 2013—58,444,185)	-12,545	-10,228
Additional paid-in-capital	1,207,493	1,677,894
Accumulated other comprehensive (loss)	-8,556	-617
Retained earnings	2,374,344	2,010,009
Total shareholders' equity available to Validus	3,587,958	3,704,094
Noncontrolling interest	458,595	497,657
Total shareholders' equity	4,046,553	4,201,751
Total liabilities, noncontrolling interests and shareholders’ equity	$10,311,621	$9,846,432

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, except Share data, unless otherwise specified
Assets
Fixed maturities, at amortized cost	$5,534,494	$5,522,853
Short-term investments, at amortized cost	1,051,222	787,670
Other investments, at amortized cost	$879,176	$723,498
Shareholders' equity
Common shares, shares authorized	571,428,571	571,428,571
Common shares, par value	$0.18	$0.18
Common shares, shares issued	155,554,224	154,488,497	152,698,191	134,503,065
Common shares, shares outstanding	83,869,845	96,044,312	107,921,259
Treasury stock, common shares	71,684,379	58,444,185

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Revenues
Gross premiums written	$2,363,286		$2,401,106		$2,166,440
Reinsurance premiums ceded	-309,233		-372,585		-307,506
Net premiums written	2,054,053		2,028,521		1,858,934
Change in unearned premiums	-51,649		73,524		14,282
Net premiums earned	2,002,404		2,102,045		1,873,216
Gain on bargain purchase, net of expenses	0		0		17,701	[1]
Net investment income	100,076		96,072		107,936
Net realized gains on investments	23,095		3,258		18,233
Change in net unrealized (losses) gains on investments	-57,973	[2]	-58,481	[2]	17,585	[2]
Income (loss) from investment affiliate	8,411		4,790		-964
Other insurance related income and other income	19,739		8,343		22,396
Foreign exchange (losses) gains	-10,630		2,505		4,798
Total revenues	2,085,122		2,158,532		2,060,901
Expenses
Losses and loss expenses	772,049	[3]	793,932	[3]	999,446	[3]
Policy acquisition costs	340,556		360,310		334,698
General and administrative expenses	329,792		315,265		263,652
Share compensation expenses	33,073		27,630		26,709
Finance expenses	63,854		64,177		53,857
Transaction expenses	8,096	[4]	0		0
Total expenses	1,547,420		1,561,314		1,678,362
Income before taxes, income from operating affiliates and (income) attributable to operating affiliate investors	537,702		597,218		382,539
Tax expense	-155		-383		-2,501
Income from operating affiliates	17,723		14,289		12,580
(Income) attributable to operating affiliate investors	-109,399		-68,763		0
Net income	445,871		542,361		392,618
Net loss (income) attributable to noncontrolling interest	35,464		-9,695		15,820
Net income available to Validus	481,335		532,666		408,438
Other comprehensive (loss) income
Change in foreign currency translation adjustments	-7,501		-1,954		3,648
Change in minimum pension liability, net of tax	-210		0		0
Change in fair value of cash flow hedge	-228		0		0
Other comprehensive (loss) income	-7,939		-1,954		3,648
Comprehensive income available to Validus	$473,396		$530,712		$412,086
Weighted average number of common shares and common share equivalents outstanding
Basic (shares)	90,354,745		102,202,274		97,184,110
Diluted (shares)	94,690,271		103,970,289		102,384,923
Basic earnings per share available to common shareholders	$5.26		$5.02		$4.13
Earnings per diluted share available to common shareholders	$5.08		$4.94		$3.99
Cash dividends declared per share	$1.20		$3.20		$1
[1]	The gain on bargain purchase, net of expenses, arose from the acquisition of Flagstone Reinsurance Holdings S.A. on November 30, 2012 and is net of transaction related expenses which included legal, financial advisory, audit related services and termination expenses.
[2]	Includes change in net unrealized gains (losses) and realized gains on investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and is included in the Consolidated Statements of Comprehensive Income as net loss (income) attributable to noncontrolling interest.
[3]	Upon closing the acquisition of Western World, an adjustment of $15,586 was made to increase net reserves to reflect fair value. This adjustment was amortized to income through a reduction in losses and loss expenses of $4,607 during the year ended December 31, 2014. The remaining fair value adjustment will be amortized in 2015.
[4]	The transaction expenses relate to costs incurred in connection with the acquisition of Western World, which was completed on October 2, 2014. Transaction expenses are primarily comprised of legal, financial advisory and audit related services.

Consolidated_Statements_of_Sha

Consolidated Statements of Shareholders' Equity (USD $)	Total	Common shares	Treasury shares	Additional paid-in capital	Accumulated other comprehensive (loss)	Retained earnings
In Thousands
Balance - Beginning of period at Dec. 31, 2011		$23,538	($6,131)	$1,893,890	($6,601)	$1,543,729
Common shares issued, net		3,184		498,136
Repurchase of common shares			-1,705	-258,257
Share compensation expenses				26,709
Dividends						-107,751
Net income	392,618					392,618
Net loss (income) attributable to noncontrolling interest	15,820					15,820
Amounts reclassified to retained earnings					0	0
Other comprehensive (loss) income					3,648
Noncontrolling interest	434,280
Total shareholders' equity	4,455,107				-2,953
Balance - End of period at Dec. 31, 2012	4,020,827	26,722	-7,836	2,160,478	-2,953	1,844,416
Common shares issued, net		314		898
Repurchase of common shares			-2,392	-511,112
Share compensation expenses				27,630
Dividends						-362,783
Net income	542,361					542,361
Net loss (income) attributable to noncontrolling interest	-9,695					-9,695
Amounts reclassified to retained earnings					4,290	-4,290
Other comprehensive (loss) income					-1,954
Noncontrolling interest	497,657
Total shareholders' equity	4,201,751				-617
Balance - End of period at Dec. 31, 2013	3,704,094	27,036	-10,228	1,677,894	-617	2,010,009
Common shares issued, net		186		5,161
Repurchase of common shares			-2,317	-508,635
Share compensation expenses				33,073
Dividends						-117,000
Net income	445,871					445,871
Net loss (income) attributable to noncontrolling interest	35,464					35,464
Amounts reclassified to retained earnings					0	0
Other comprehensive (loss) income					-7,939
Noncontrolling interest	458,595
Total shareholders' equity	4,046,553				-8,556
Balance - End of period at Dec. 31, 2014	$3,587,958	$27,222	($12,545)	$1,207,493	($8,556)	$2,374,344

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Cash flows provided by (used in) operating activities
Net income	$445,871		$542,361		$392,618
Adjustments to reconcile net income to cash provided by (used in) operating activities:
Share compensation expenses	33,073		27,630		26,709
(Gain) loss on sale / deconsolidation of subsidiary	-2,081		3,237		0
Bargain purchase gain	0		0		-49,702
Amortization of discount on senior notes	108		108		108
(Income) loss from investment affiliate	-8,411		-4,790		964
Net realized (gains) on investments	-23,095		-3,258		-18,233
Change in net unrealized losses (gains) on investments	57,973	[1]	58,481	[1]	-17,585	[1]
Amortization of intangible assets	4,538		4,162		10,159
(Income) from operating affiliates	-17,723		-14,289		-12,580
Foreign exchange losses (gains) included in net income	23,591		1,912		-16,123
Amortization of premium on fixed maturities	19,107		19,093		24,289
Change in:
Premiums receivable	22,810		127,442		19,860
Deferred acquisition costs	-27,026		12,319		-1,875
Prepaid reinsurance premiums	34,370		-3,658		3,116
Loss reserves recoverable	81,824		69,910		40,708
Paid losses recoverable	43,580		-33,807		54,248
Income taxes recoverable	0		0		522
Accrued investment income	2,417		2,499		7,404
Other assets	32,448		-80,718		-9,618
Reserve for losses and loss expenses	-395,499		-472,883		116,902
Unearned premiums	17,280		-69,866		-17,148
Reinsurance balances payable	-31,061		-4,724		-12,365
Deferred income taxes	-45,380		-1,008		1,040
Accounts payable and accrued expenses	-26,933		85,121		-253
Net cash provided by operating activities	241,781		265,274		543,165
Cash flows provided by (used in) investing activities
Proceeds on sales of investments	4,756,555		4,370,548		3,393,740
Proceeds on maturities of investments	554,619		490,459		548,226
Purchases of fixed maturities	-4,379,314		-5,392,728		-3,726,611
(Purchases) sales of short-term investments, net	-121,264		353,353		56,502
Purchases of other investments	-119,815		-38,492		-491,210
Decrease (increase) in securities lending collateral	2,922		-3,167		7,771
Redemption from operating affiliates	77,544		86,657		0
Decrease (increase) in restricted cash	27,489		-172,962		-3,493
Proceeds on sale of subsidiary, net of cash	16,459		21,388		0
Purchase of subsidiary, net of cash acquired	-643,545		0		17,196
Net cash provided by (used in) investing activities	121,582		-321,436		-302,214
Cash flows provided by (used in) financing activities
Proceeds on issuance of notes payable to operating affiliates	680,027		442,412		0
Repayments on notes payable to operating affiliates	-617,068		-3,553		0
Issuance of common shares, net	5,347		1,211		3,015
Purchases of common shares under share repurchase program	-510,952		-513,504		-259,962
Dividends paid	-117,043		-360,071		-110,037
(Decrease) increase in securities lending payable	-2,922		3,167		-7,771
Third party investment in redeemable noncontrolling interest	68,200		92,190		0
Third party redemption of redeemable noncontrolling interest	-10,496		-19,400		0
Investment in third party noncontrolling interest	0		58,500		450,100
Third party subscriptions received in advance	15,400		35,000		19,400
Net cash (used in) provided by financing activities	-489,507		-264,048		94,745
Effect of foreign currency rate changes on cash and cash equivalents	-30,764		-6,364		17,540
Net (decrease) increase in cash	-156,908		-326,574		353,236
Cash and cash equivalents - beginning of year	734,148		1,060,722		707,486
Cash and cash equivalents - end of year	577,240		734,148		1,060,722
Taxes paid during the year	42,689		5,407		3,832
Interest paid during the year	54,526		52,191		43,249
Operating Affiliates [Member]
Adjustments to reconcile net income to cash provided by (used in) operating activities:
(Income) from operating affiliates	-17,723		-14,289
Cash flows provided by (used in) investing activities
Investments in affiliates	-37,600		-22,000		-91,500
Investment Affiliates [Member]
Cash flows provided by (used in) investing activities
Investments in affiliates	($12,468)		($14,492)		($12,835)
[1]	Includes change in net unrealized gains (losses) and realized gains on investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and is included in the Consolidated Statements of Comprehensive Income as net loss (income) attributable to noncontrolling interest.

Nature_of_the_business

Nature of the business	12 Months Ended
	Dec. 31, 2014
Nature Of Business [Abstract]
Nature of the business	Nature of the business
	Validus Holdings, Ltd. (together with its wholly and majority owned subsidiaries, the “Company”) was incorporated under the laws of Bermuda on October 19, 2005. The Company provides reinsurance coverage, insurance coverage and insurance linked securities management through four distinct global operating segments, Validus Re, AlphaCat, Talbot and Western World. Validus Re is a Bermuda-based reinsurance segment focused on short-tail lines of reinsurance. AlphaCat is a Bermuda-based investment adviser, managing capital from third parties and the Company in insurance linked securities and other investments in the property catastrophe reinsurance space. Talbot is a specialty insurance segment, primarily operating within the Lloyd's insurance market through Syndicate 1183. Western World is a U.S. based specialty excess and surplus lines insurance segment.
	On November 30, 2012, pursuant to a merger agreement, the Company acquired all of the outstanding common shares of Flagstone Reinsurance Holdings, S.A. ("Flagstone") in exchange for 0.1935 Company common shares and $2.00 cash per Flagstone common share (the "Flagstone Acquisition"). For segmental reporting purposes, the results of Flagstone’s operations since the acquisition date have been included within the Validus Re segment in the Consolidated Financial Statements. Refer to Note 5 "Business combinations" for further information.
	On October 9, 2013, the Company completed the sale of its wholly-owned Cyprus-domiciled subsidiary, Flagstone Alliance Insurance and Reinsurance plc for net cash proceeds of $21,400.
	On October 2, 2014, the Company acquired all of the outstanding shares of Western World Insurance Group Inc. ("Western World"), a U.S. based specialty excess and surplus lines insurance company. The results of operations for Western World are consolidated from the date of acquisition. Refer to Note 5 "Business combinations" for further information.

Basis_of_preparation_and_conso

Basis of preparation and consolidation	12 Months Ended
	Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of preparation and consolidation	Basis of preparation and consolidation
	These Consolidated Financial Statements include Validus Holdings, Ltd. and its wholly and majority owned subsidiaries and have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Certain amounts with respect to cash and cash equivalents have been revised to correct certain prior period comparatives in these Consolidated Financial Statements.
	The Consolidated Balance Sheet for the year ended December 31, 2013 includes revisions to reduce cash and cash equivalents by $322,198 and increase restricted cash, short-term investments and other investments by $200,492, $35,936 and $85,770, respectively. There is no change to the sub-total of total investments and cash, or the totals of total assets or total shareholders’ equity.
	The Consolidated Statements of Cash Flows for the years ended December 31, 2013 and 2012, includes revisions to (decrease) net cash provided by (used in) investing activities by ($163,541) and ($33,299), respectively. There are no changes to the sub-totals of net cash provided by (used in) operating activities or effect of foreign currency rate changes on cash and cash equivalents. These revisions resulted in a decrease in net (decrease) increase in cash of ($163,541) and ($33,299), for the years ended December 31, 2013 and 2012, respectively.
	The effect of these revisions does not impact any per-share amounts or other components of equity or net assets in the statement of financial position in any of the prior periods presented. The Company does not believe these revisions are material to any prior periods. The Company has revised these prior period amounts to provide comparability with current period balances and cash flows. All significant intercompany accounts and transactions have been eliminated.
	The preparation of these financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. While management believes that the amounts included in the Consolidated Financial Statements reflect its best estimates and assumptions, actual results could differ from those estimates. The Company’s principal estimates include:
	•reserve for losses and loss expenses;
	•premium estimates for business written on a line slip or proportional basis;
	•the valuation of goodwill and intangible assets;
	•reinsurance recoverable balances including the provision for uncollectible amounts; and
	•investment valuation of financial assets.
	The term “ASC” used in these notes refers to Accounting Standard Codification issued by the United States Financial Accounting Standards Board (“FASB”).

Significant_accounting_policie

Significant accounting policies	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Significant accounting policies	Significant accounting policies
	The following is a summary of significant accounting policies adopted by the Company.
	(a)	Premiums
	Insurance premiums written are recorded in accordance with the terms of underlying policies. Reinsurance premiums written are recorded at the inception of the policy and are estimated based on information received from brokers, ceding companies and reinsureds, and any subsequent differences arising on such estimates will be recorded in the periods in which they are determined. Premiums written are earned on a pro-rated basis over the term of the policy. For contracts and policies written on a losses occurring basis, the risk period is generally the same as the contract or policy terms. For contracts written on a policies attaching basis, the risk period is based on the terms of the underlying contracts and policies and is generally assumed to be 24 months. The portion of the premiums written applicable to the unexpired terms of the underlying contracts and policies in force is recorded as unearned premiums.
	Reinstatement premiums are recorded at the time a loss event occurs and coverage limits for the remaining life of the contract are reinstated under predefined contract terms. The accrual of reinstatement premiums is based on our estimate of losses and loss expenses, which reflects management’s judgment, as described in Note 3(c) "Reserve for losses and loss expenses" below.
	(b)	Policy acquisition costs
	Policy acquisition costs are costs that vary with, and are directly related to, the successful production of new and renewal business, and consist principally of commissions and brokerage expenses. Acquisition costs are shown net of commissions earned on reinsurance ceded. These costs are deferred and amortized over the periods in which the related premiums are earned. Deferred acquisition costs are limited to their estimated realizable value based on the related unearned premiums and anticipated claims expenses. The realizable value of the Company’s deferred acquisition costs is determined without consideration of investment income. Policy acquisition costs also include profit commissions. Profit commissions are recognized on a basis consistent with our estimate of losses and loss expenses.
	(c)	Reserve for losses and loss expenses
	The reserve for losses and loss expenses includes reserves for unpaid reported losses and for losses incurred but not reported (“IBNR”). The reserve for unpaid reported losses and loss expenses is established by management based on reports from brokers, ceding companies and insureds and represents the estimated ultimate cost of events or conditions that have been reported to, or specifically identified by, the Company. The reserve for incurred but not reported losses and loss expenses is established by management based on actuarially determined estimates of ultimate losses and loss expenses. Inherent in the estimate of ultimate losses and loss expenses are expected trends in claim severity and frequency and other factors which may vary significantly as claims are settled. Accordingly, ultimate losses and loss expenses may differ materially from the amounts recorded in the Consolidated Financial Statements. These estimates are reviewed regularly and, as experience develops and new information becomes known, the reserves are adjusted as necessary. Such adjustments, if any, will be recorded in earnings in the period in which they become known. Prior period development arises from changes to these estimates recognized in the current year that relate to reserves for losses and loss expenses established in previous calendar years.
	(d)	Reinsurance
	In the normal course of business, the Company seeks to reduce the potential amount of loss arising from claims events by reinsuring certain levels of risk assumed in various areas of exposure with other insurers or reinsurers. The accounting for reinsurance ceded depends on the method of reinsurance. If the policy is on a “losses occurring” basis, reinsurance premiums ceded are expensed (and any commissions thereon are earned) on a pro-rata basis over the period the reinsurance coverage is provided. If the policy is a “risks attaching” policy, reinsurance premiums ceded are expensed (and any commissions thereon are earned) in line with the earning of the gross premiums to which the risk attaching policy relates. Prepaid reinsurance premiums represent the portion of premiums ceded applicable to the unexpired term of policies in force. Mandatory reinstatement premiums ceded are recorded at the time the loss event occurs. Reinsurance recoverables are based on contracts in force at the time of the underlying loss event. The method for determining the reinsurance recoverable on unpaid losses and loss expenses involves the actuarial estimates of unpaid losses and loss expenses as well as a determination of the Company’s ability to cede unpaid losses and loss expenses under its reinsurance treaties. The use of different assumptions could have a material effect on the provision for uncollectible reinsurance. To the extent the creditworthiness of the Company’s reinsurers was to deteriorate due to adverse events affecting the reinsurance industry, such as a large number of major catastrophes, actual uncollectible amounts could be significantly greater than the Company’s provision. Amounts recoverable from reinsurers are estimated in a manner consistent with the underlying liabilities.
	(e)	Investments
	All investments are carried at fair value with interest and dividend income and realized and unrealized gains and losses included in net income for the year.
	All investment transactions are recorded on a first-in-first-out basis and realized gains and losses on the sale of investments are determined on the basis of amortized cost. Interest on fixed maturity securities is recorded in net investment income when earned and is adjusted for any amortization of premium or accretion of discount.
	For mortgage-backed securities, and any other holdings for which there is a prepayment risk, prepayment assumptions are evaluated and revised as necessary. Any adjustments required due to the resultant change in effective yields and maturities are recognized retrospectively. Prepayment fees or call premiums that are only payable to the Company when a security is called prior to its maturity, are earned when received and reflected in net investment income.
	Short-term investments primarily comprise of investments with a remaining maturity of less than one year at time of purchase and money market funds held at the Company’s investment managers. Certain short-term investments relate to funds held in trust in support of collateralized reinsurance transactions.
	Restricted cash primarily relates to funds held in trust for support of collateralized reinsurance transactions.
	The fair value of other investments is generally recorded on the basis of the net asset valuation criteria established by the managers of the investments, normally based upon the governing documents of such investments. In addition, due to a lag in reporting, some of the fund managers, fund administrators, or both, are unable to provide final fund valuations as of the Company’s reporting date. In these circumstances, the Company estimates the fair value of these funds by starting with the prior month’s or prior quarter's fund valuation, adjusting these valuations for capital calls, redemptions or distributions and the impact of changes in foreign currency exchange rates, and then estimating the return for the current period. In circumstances in which the Company estimates the return for the current period, it uses all credible information available. This includes utilizing preliminary estimates reported by its fund managers, obtaining the valuation of underlying portfolio investments where such underlying investments are publicly traded and therefore have a readily observable price, using information that is available to the Company with respect to the underlying investments, reviewing various indices for similar investments or asset classes, as well as estimating returns based on the results of similar types of investments for which the Company has reported results, or other valuation methods, as necessary. Actual final fund valuations may differ, perhaps materially so, from the Company’s estimates and these differences are recorded in the period they become known as a change in estimate.
	(f)	Fair value of financial instruments
	Fair value is defined as the price received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date reflecting the highest and best use valuation concepts. The guidance for “Fair Value Measurement and Disclosure” provides a framework for measuring fair value by creating a hierarchy of fair value measurements that distinguishes market data between observable independent market inputs and unobservable market assumptions by the reporting entity. The guidance further expands disclosures about such fair value measurements. The guidance applies broadly to most existing accounting pronouncements that require or permit fair value measurements (including both financial and non-financial assets and liabilities) but does not require any new fair value measurements. The Company has adopted all authoritative guidance in effect as of the balance sheet date regarding certain market conditions that allow for fair value measurements that incorporate unobservable inputs where active market transaction based measurements are unavailable.
	(g)	Derivative instruments
	Fair Value Hedges
	The Company uses derivative instruments in the form of foreign currency forward exchange contracts to manage foreign currency risk. A foreign currency forward exchange contract involves an obligation to purchase or sell a specified amount of a specified currency at a future date at a price set at the time of the contract. Foreign currency forward exchange contracts will not eliminate fluctuations in the value of our assets and liabilities denominated in foreign currencies but rather allow the Company to establish a rate of exchange for a future point in time. The foreign currency forward exchange contracts are recorded as derivatives at fair value as either assets or liabilities, depending on their rights or obligations, with changes in fair value recorded as a net foreign exchange gain or loss in the Company’s Statements of Comprehensive Income.
	To qualify for hedge accounting treatment, a derivative must be highly effective in mitigating the designated changes in value or cash flow of the hedged item. The Company formally documents all relationships between designated hedging instruments and hedged items, as well as its risk management objective and strategy for undertaking various hedge transactions. The documentation process includes linking derivatives to specific assets or liabilities on the balance sheet. The Company also formally assesses, both at the hedge’s inception and on an ongoing basis, whether the derivatives that are used in hedging transactions are highly effective in offsetting changes in fair values or cash flows of hedged items. The Company assesses the effectiveness of its designated hedges on an individual currency basis. If the ratio obtained with this method is within the range of 80% to 125%, the Company considers the hedge effective.
	The Company discontinues hedge accounting prospectively when it is determined that the derivative is no longer highly effective in offsetting changes in the fair value or cash flows of a hedged item; the derivative is de-designated as a hedging instrument; or the derivative expires or is sold, terminated or exercised. To the extent that the Company discontinues hedge accounting, because, based on management’s assessment, the derivative no longer qualifies as an effective hedge, the derivative will continue to be carried in the Consolidated Balance Sheets at its fair value, with changes in its fair value recognized in current period net income through foreign exchange gains (losses).
	Cash Flow Hedges
	The Company uses derivative instruments in the form of interest rate swaps to manage the interest rate exposure associated with certain assets and liabilities. These derivatives are recorded at fair value. Changes in the fair value of a derivative that is designated and qualifies as a cash flow hedge are recorded in other comprehensive income (“OCI”) and are reclassified into earnings when the variability of the cash flow of the hedged item impacts earnings. Gains and losses on derivative contracts that are reclassified from OCI to current period earnings are included in the line item in the Consolidated Statements of Comprehensive Income in which the cash flows of the hedged item are recorded. Any hedge ineffectiveness is recorded immediately in current period earnings.
	To qualify for hedge accounting treatment, a derivative must be highly effective in mitigating the designated changes in value or cash flow of the hedged item. The Company formally documents all relationships between designated hedging instruments and hedged items, as well as its risk management objective and strategy for undertaking various hedge transactions. The documentation process includes linking derivatives to specific assets or liabilities on the balance sheet. The Company also formally assesses, both at the hedge's inception and on an ongoing basis (when required), whether the derivatives that are used in hedging transactions are highly effective in offsetting changes in fair values or cash flows of hedged items. The Company assesses the effectiveness of its designated hedges on an individual contract basis. The Company currently applies the long haul method when assessing the hedge's effectiveness.
	The Company discontinues hedge accounting prospectively when it is determined that the derivative is no longer highly effective in offsetting changes in the fair value or cash flows of a hedged item; the derivative is de-designated as a hedging instrument; or the derivative expires or is sold, terminated or exercised. When hedge accounting is discontinued because the Company becomes aware that it is not probable that the forecasted transaction will occur, the derivative continues to be carried on the balance sheet at its fair value, and gains and losses that were accumulated in OCI are recognized immediately in earnings.
	(h)	Cash and cash equivalents
	The Company considers time deposits and money market funds with an original maturity of one month or less as equivalent to cash.
	(i)	Foreign exchange
	The U.S. dollar is the functional currency of the Company and the majority of its subsidiaries. For these companies, monetary assets and liabilities denominated in foreign currencies are revalued at the exchange rates in effect at the balance sheet date and revenues and expenses denominated in foreign currencies are translated at the prevailing exchange rate on the transaction date with the resulting foreign exchange gains and losses included in earnings. Non-monetary assets and liabilities denominated in foreign currencies are revalued at the exchange rate in effect at the time of the underlying transaction.
	Assets and liabilities of subsidiaries whose functional currency is not the U.S. dollar are translated at prevailing year end exchange rates. Revenue and expenses of such foreign operations are translated at average exchange rates during the year. The net effect of translation differences between functional and reporting currencies in foreign operations, net of applicable deferred income taxes, is included in accumulated other comprehensive income ("AOCI").
	(j)	Stock plans
	The Company accounts for its stock plans in accordance with the U.S. GAAP fair value recognition provisions for “Stock Compensation.” Accordingly, the Company recognizes the compensation expense for stock option grants, restricted share grants and performance share awards based on the fair value of the award on the date of grant over the requisite service period.
	(k)	Warrants
	The Company has accounted for certain warrant contracts issued to our sponsoring investors in conjunction with the capitalization of the Company, and which may be settled by the Company using either the physical settlement or net-share settlement methods, in accordance with U.S. GAAP guidance for “Derivatives and Hedging, Contracts in Entity’s Own Equity.” Accordingly, the fair value of these warrants has been recorded in equity as an addition to additional paid-in capital.
	(l)	Earnings per share
	Basic earnings per common share is calculated by dividing net income available to common shareholders by the weighted average number of common shares outstanding. Earnings per diluted common share are based on the weighted average number of common shares and share equivalents excluding any anti-dilutive effects of warrants, options and other awards under stock plans.
	(m)	Income taxes and uncertain tax provisions
	Deferred tax assets and liabilities are recorded in accordance with U.S. GAAP “Income Taxes” guidance. Consistent with this guidance, the Company records deferred income taxes which reflect the tax effect of the temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and their respective tax bases.
	The Company and its Bermuda domiciled subsidiaries are not subject to any income, withholding or capital gains taxes under current Bermuda law. The Company has operations in subsidiary form in various other jurisdictions around the world, including but not limited to the U.K., U.S., Switzerland, Luxembourg and Canada that are subject to relevant taxes in those jurisdictions.
	The Company recognizes the tax benefits of uncertain tax positions only where the position is more likely than not to be sustained upon audit by tax authorities. The Company would recognize accruals for any interest and penalties related to uncertain tax positions in income tax expenses.
	(n)	Goodwill and other intangible assets
	The Company accounts for goodwill and other intangible assets recognized in business combinations in accordance with ASC Topic 805 “Business Combinations.”
	A purchase price paid that is in excess of the fair value of the net assets (“goodwill”) arising from a business combination is recorded as an asset, and is not amortized. Where the total fair value of net assets acquired exceeds consideration paid (“negative goodwill”), the acquirer will record a gain as a result of the bargain purchase, to be recognized through the consolidated statements of comprehensive income at the close of the transaction.
	Intangible assets with a finite life are amortized over the estimated useful life of the asset. Intangible assets with an indefinite useful life are not amortized. Refer to Note 6 "Goodwill and other intangible assets" for further information.
	Goodwill and indefinite-lived intangible assets are tested for impairment on an annual basis or more frequently if events or changes in circumstances indicate that the carrying amount may not be recoverable. Such events or circumstances may include an economic downturn in a geographic market or change in the assessment of future operations. In performing this test, the Company may first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount as a basis for determining whether it is necessary to perform the two-step goodwill impairment test described in ASC Topic 350 “Intangibles—Goodwill and Other.” Similarly, the Company may first assess qualitative factors to determine whether it is more likely than not that an indefinite-lived intangible asset is impaired as a basis for determining whether it is necessary to perform the quantitative impairment described in ASC Topic 350 "Intangibles - Goodwill and Other - General Intangibles Other than Goodwill." The factors assessed in making this determination included the overall insurance industry outlook, business strategy, premium rates, earnings sustainability, market capitalization and the regulatory and political environment.
	If the goodwill or intangible asset is impaired, it is written down to its realizable value with a corresponding expense reflected in the Consolidated Statements of Comprehensive Income.
	(o)	Investments in affiliates
	Investments in which the Company has significant influence over the operating and financial policies of the investee are accounted for under the equity method of accounting. Under this method, the Company records its proportionate share of income or loss from such investments in its results for the period.
	(p)	Variable interest entities
	The Company determines whether it has relationships with entities defined as variable interest entities (“VIEs”) in accordance with ASC Topic 810 "Consolidation." Entities that do not have sufficient equity at risk to allow the entity to finance its activities without additional financial support or in which the equity investors, as a group, do not have the characteristic of a controlling financial interest are referred to as variable interest entities. A VIE is consolidated by the variable interest holder that is determined to be the primary beneficiary.
	The primary beneficiary is defined as the variable interest holder that is determined to have the controlling financial interest as a result of having both (i) the power to direct the activities of a VIE that most significantly impact the economic performance of the VIE and (ii) the obligation to absorb losses or right to receive benefits from the VIE that could potentially be significant to the VIE. At inception of the VIE, as well as following an event that requires reassessment, the Company determines whether it is the primary beneficiary based on an analysis of the Company's level of involvement in the VIE, the contractual terms, and the overall structure of the VIE. Those VIEs that have all the attributes of an investment company are assessed under ASC Topic 810, excluding the changes that were as a result of the issuance of FASB Statement No. 167 "Amendments to FASB Interpretation No. 46(R)."
	The Company accounts for its investments in the AlphaCat Insurance Linked Securities (“ILS”) Funds and the BetaCat ILS Funds as variable interest entities. See Note 9 "Investments in affiliates" for further details.
	(q)	Noncontrolling interests
	The Company accounts for its noncontrolling interests in accordance with ASC Topic 810 “Consolidation.” Redeemable noncontrolling interests are presented as a mezzanine item, between liabilities and shareholders' equity, in the Company's Consolidated Balance Sheet and the non-redeemable noncontrolling interests are presented within shareholders' equity in the Company's Consolidated Balance Sheets and Consolidated Statements of Shareholders' Equity. The net (income) loss attributable to noncontrolling interest is presented separately in the Company's Consolidated Statements of Comprehensive Income. Refer to Note 9 "Investments in affiliates" for further details.

Recent_accounting_pronouncemen

Recent accounting pronouncements	12 Months Ended
	Dec. 31, 2014
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent accounting pronouncements	Recent accounting pronouncements
	(a)	Adoption of New Accounting Standards
	Parent’s Accounting for the Cumulative Translation Adjustment upon Derecognition of Certain Subsidiaries or Groups of Assets within a Foreign Entity or of an Investment in a Foreign Entity
	In March 2013, the FASB issued Accounting Standard Update No. 2013-05, “Parent’s Accounting for the Cumulative Translation Adjustment upon Derecognition of Certain Subsidiaries or Groups of Assets within a Foreign Entity or of an Investment in a Foreign Entity” (ASU 2013-05). The objective of this Update is to resolve the diversity in practice about whether Subtopic 810-10, Consolidation-Overall, or Subtopic 830-30, Foreign Currency Matters-Translation of Financial Statements, applies to the release of the cumulative translation adjustment into net income when a parent either sells a part or all of its investment in a foreign entity or no longer holds a controlling financial interest in a subsidiary within a foreign entity. The amendments became effective for the Company on January 1, 2014. Adoption of this guidance did not have a material impact on the Company’s Consolidated Financial Statements.
	Financial Services - Investment Companies - Amendments to the Scope, Measurement, and Disclosure Requirements
	In June 2013, the FASB issued Accounting Standard Update No. 2013-08, “Financial Services - Investment Companies - Amendments to the Scope, Measurement, and Disclosure Requirements” (ASU 2013-08). The amendments in this Update change the assessment of whether an entity is an investment company by developing a new two-tiered approach for that assessment, which requires an entity to possess certain fundamental characteristics while allowing judgment in assessing other typical characteristics. The new approach requires an entity to assess all of the characteristics of an investment company and consider its purpose and determine whether it is an investment company. The amendments became effective for the Company on January 1, 2014. The Company performed an assessment and has concluded that the AlphaCat ILS funds meet the characteristics outlined in this Update and therefore will continue to be treated as investment companies. Adoption of this guidance did not have a material impact on the Company’s Consolidated Financial Statements.
	Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists
	In July 2013, the FASB issued Accounting Standard Update 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” (ASU 2013-11). This Update applies to all entities that have unrecognized tax benefits when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists at the reporting date. An unrecognized tax benefit should be presented in the financial statements as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward. To the extent a net operating loss carryforward is not available to settle any additional income taxes that would result from the disallowance of a tax position at the reporting date, the unrecognized tax benefit should be presented in the financial statements as a liability and should not be combined with deferred tax assets. The amendments became effective for the Company on January 1, 2014. Adoption of this guidance did not have a material impact on the Company’s Consolidated Financial Statements.
	(b)	Recently Issued Accounting Standards Not Yet Adopted
	In May 2014, the FASB issued Accounting Standard Update No. 2014-09, “Revenue from Contracts with Customers” (ASU 2014-09). The guidance in this Update affects any entity that either enters into contracts with customers to transfer goods or services or enters into contracts for the transfer of nonfinancial assets, unless those contracts are within the scope of other standards (for example, insurance contracts or lease contracts). The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised 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 amendments in this Update are effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Earlier adoption is not permitted. The Company is currently evaluating the impact of this guidance on the Company’s Consolidated Financial Statements.
	In June 2014, the FASB issued Accounting Standard Update No. 2014-12, “Compensation - Stock Compensation (Topic 718) - Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period” (ASU 2014-12). The amendments in this Update apply to all reporting entities that grant their employees share-based payments in which the terms of the award provide that a performance target that affects vesting could be achieved after the requisite service period. That is the case when an employee is eligible to retire or otherwise terminate employment before the end of the period in which a performance target (for example, an initial public offering or a profitability target) could be achieved and still be eligible to vest in the award if and when the performance target is achieved. The amendments in this Update are effective for annual reporting periods beginning after December 15, 2015, including interim periods within that reporting period. Earlier adoption is permitted. The Company is currently evaluating the impact of this guidance; however, it is not expected to have a material impact on the Company's Consolidated Financial Statements.
	In August 2014, the FASB issued Accounting Standard Update 2014-13, “Consolidation (Topic 810) - Measuring the Financial Assets and the Financial Liabilities of a Consolidated Collateralized Financing Entity” (ASU 2014-13). The fair value of the financial assets of a collateralized financing entity, as determined under GAAP, may differ from the fair value of its financial liabilities even when the financial liabilities have recourse only to the financial assets. The amendments in this Update provide an alternative to Topic 820 for measuring the financial assets and the financial liabilities of a consolidated collateralized financing entity to eliminate that difference. The amendments in this Update are effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2015. Early adoption is permitted as of the beginning of an annual period. The Company is currently evaluating the impact of this guidance on the Company’s Consolidated Financial Statements.
	In August 2014, the FASB issued Accounting Standard Update 2014-15, “Presentation of Financial Statements - Going Concern - Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern” (ASU 2014-15). The amendments in this Update require management to assess an entity’s ability to continue as a going concern by incorporating and expanding upon certain principles that are currently in U.S. auditing standards. The amendments in this Update are effective for the annual period ending after December 15, 2016, and for annual periods and interim periods thereafter. Early application is permitted. The Company has evaluated the impact of this guidance, it will not have a material impact on the Company's Consolidated Financial Statements.
	In February 2015, the FASB issued Accounting Standard Update 2015-02, “Consolidation (Topic 810) Amendments to the Consolidation Analysis” (ASU 2015-02). The amendments in this update modify the evaluation of whether limited partnerships and similar legal entities are variable interest entities (VIEs) or voting interest entities. The amendment also eliminates the presumption that a general partner should consolidate a limited partnership and affects the consolidation analysis of reporting entities that are involved with VIEs, particularly those that have fee arrangements and related party relationships. The amendment also provides a scope exception from consolidation guidance for reporting entities with interests in legal entities that are required to comply with or operate in accordance with requirements that are similar to those in Rule 2a-7 of the Investment Company Act of 1940 for registered money market funds. The amendments in this Update are effective for interim and annual periods beginning after December 15, 2015. Early adoption is permitted. The Company is currently evaluating the impact of this guidance on the Company’s Consolidated Financial Statements.

Business_combination

Business combination	12 Months Ended
	Dec. 31, 2014
Business Combinations [Abstract]
Business combination	Business combinations
	(a)	Western World Insurance Group, Inc. acquisition
	On October 2, 2014, Validus Specialty, Inc., wholly owned subsidiary of the Company acquired all of the issued and outstanding capital stock of Western World for an aggregate purchase price of $692,305 in cash. The Western World acquisition was undertaken to enhance the Company's access to the specialty U.S. commercial insurance market. Additional factors that added to the value of Western World included its State Licenses, Brand Name, Distribution Network and Technology. These factors resulted in a market value greater than the value of net tangible and intangible assets which resulted in the recognition of goodwill. This goodwill is reflective of the strategic benefits that a U.S. based insurer can provide to the Company.
	For reporting purposes, the results of Western World’s operations have been included in the Consolidated Financial Statements as a separate segment from the acquisition date.
	The estimates of fair values for tangible and intangible assets acquired and liabilities assumed were determined by management based on various market and income analyses. Significant judgment was required to arrive at these estimates of fair value and changes to assumptions used could have led to materially different results.
	The fair value of net assets acquired, including pro forma GAAP adjustments, are summarized as follows:
	Total purchase price				$	692,305
	Assets acquired
		Cash and cash equivalents	$	48,760
		Investments	1,126,185
		Receivables	37,848
		Other assets	19,418
		Tangible assets acquired			1,232,211
		Intangible asset - State licenses	$	12,325
		Intangible asset - Brand name	5,756
		Intangible asset - Distribution network	4,651
		Intangible asset - Technology	2,323
		Intangible assets acquired			$	25,055
	Liabilities acquired
		Net loss reserves and paid losses recoverable	$	523,315
		Unearned premiums, net of expenses	135,686
		Other liabilities	81,464
		Liabilities acquired			740,465
	Excess purchase price (goodwill)				$	175,504
	For details on the intangible assets acquired, refer to Note 6: "Goodwill and other intangible assets".
	The Company also incurred transaction expenses related to the Western World acquisition. Transaction expenses included legal, financial advisory and audit related services.
	Supplemental Pro Forma Information
	Operating results of Western World have been included in the Consolidated Financial Statements from the October 2, 2014 acquisition date. The following selected unaudited pro forma financial information has been provided to present a summary of the combined results of the Company and Western World, assuming the transaction had been effected on January 1, 2013.
	The unaudited pro forma data is for informational purposes only and does not necessarily represent results that would have occurred if the transaction had taken place on the basis assumed above.
		Year ended			Year ended
		31-Dec-14			31-Dec-13
		(unaudited)			(unaudited)
	Net premiums earned	$	2,216,349		$	2,325,407
	Net operating income	$	481,179		$	645,696
	Net income	$	448,071		$	561,832
	The following selected audited information has been provided to present a summary of the results of Western World that have been included in the Consolidated Financial Statements for the year ended December 31, 2014.
		From Acquisition Date to
		31-Dec-14
	Net premiums written	$	58,807
	Total revenue	78,325
	Total expenses	(66,882		)
	Net income	$	11,443
	(b)	Flagstone Reinsurance Holdings S.A. acquisition
	On November 30, 2012, pursuant to a merger agreement, the Company acquired all of the outstanding common shares of Flagstone Reinsurance Holdings, S.A. ("Flagstone") in exchange for 0.1935 Company common shares and $2.00 cash per Flagstone common share (the "Flagstone Acquisition"). The Flagstone Acquisition was undertaken to enhance the Company's leadership position in the property catastrophe reinsurance industry and to create a company with greater size and economies of scale.
	For segmental reporting purposes, the results of Flagstone’s operations since the acquisition date have been included within the Validus Re segment in the Consolidated Financial Statements.
	The aggregate purchase price paid by the Company was $646,037 for adjusted tangible net assets acquired of $689,742. Reduced investment yields and lower returns on equity have led to many publicly traded reinsurance companies trading at discounts. This was the primary factor responsible for a purchase price less than the fair value of Flagstone's net assets, and the recognition of a bargain purchase gain on acquisition.
	The estimates of fair values for tangible assets acquired and liabilities assumed were determined by management based on various market and income analyses and asset appraisals. Significant judgment was required to arrive at these estimates of fair value and changes to assumptions used could have led to materially different results.
	In addition, at closing, the Company recorded a $2,595 intangible asset for the acquired Flagstone customer relationships. This intangible asset was related to the acquired broker distribution network and was fair valued using a variation of the income approach. Under this approach, the Company estimated the present value of expected future cash flows to an assumed hypothetical market participant resulting from the existing Flagstone customer relationships, considering attrition, and discounting at a weighted average cost of capital. In addition, the Company also recorded a $3,402 intangible asset for the acquired Flagstone brand name.
	The composition of the purchase price and the fair value of net assets acquired is summarized as follows:
	Total allocable purchase price
		Flagstone shares outstanding at November 30, 2012	73,852,137
		Exchange ratio	0.1935
		Validus common shares issued, gross of taxes withheld	14,290,389
		Validus share price at acquisition	$	34.87
		Total value of Validus shares issued			$	498,306
		Total cash consideration paid at $2.00 per Flagstone share			147,731
		Total allocable purchase price			646,037
	Tangible assets acquired
		Cash and cash equivalents	$	159,339
		Investments	1,323,002
		Receivables (a)	171,620
		Other assets	129,245
		Tangible assets acquired			$	1,783,206
	Liabilities acquired
	Net loss reserves and paid losses recoverable	$	639,641
	Unearned premiums, net of expenses	104,592
	Debentures payable	250,657
	Other liabilities	98,574
	Liabilities acquired			$	1,093,464
Net tangible assets acquired, at fair value				689,742
Bargain purchase gain before establishment of intangible assets				43,705
	Intangible asset—customer relationships and brand name			5,997
Bargain purchase gain on acquisition of Flagstone				$	49,702
(a)	Premiums receivable of $171,620 were net of an allowance for doubtful accounts of $2,216.
The Company also incurred transaction and termination expenses related to the Flagstone Acquisition. Transaction expenses included legal and financial advisory services. Termination expenses are primarily comprised of severance costs in connection with certain Flagstone employment contracts that have been terminated. Finally, the customer relationships and brand name intangible assets have been fully amortized at the acquisition date as it was not expected to significantly contribute to the Company’s future cash flows beyond December 31, 2012. The gain on bargain purchase, net of expenses has been presented as a separate line item in the Company’s Consolidated Statements of Comprehensive Income, and is composed of the following:
	Year Ended
	31-Dec-12
Bargain purchase gain on acquisition of Flagstone	$	49,702
Transaction expenses	(5,760		)
Termination expenses	(20,244		)
Amortization of intangible asset—customer relationships and brand name	(5,997		)
Gain on bargain purchase, net of expenses	$	17,701
Supplemental Pro Forma Information
Operating results of Flagstone have been included in the Consolidated Financial Statements from the November 30, 2012 acquisition date. The following selected unaudited pro forma financial information has been provided to present a summary of the combined results of the Company and Flagstone, assuming the transaction had been effected on January 1, 2011. The unaudited pro forma data is for informational purposes only and does not necessarily represent results that would have occurred if the transaction had taken place on the basis assumed above.
	Year ended			Year ended
	31-Dec-12			31-Dec-11
	(unaudited)			(unaudited)
Revenues
Gross premiums written	$	2,536,535		$	2,914,388
Reinsurance premiums ceded	(397,008		)	(520,506		)
Net premiums written	2,139,527			2,393,882
Change in unearned premiums	86,935			(20,261		)
Net premiums earned	2,226,462			2,373,621
Net investment income	126,140			143,472
Net realized gains on investments	63,601			37,366
Net unrealized gains (losses) on investments	5,654			(47,101		)
(Loss) from investment affiliate	(964		)	—
Other income	29,984			11,152
Foreign exchange gains (losses)	1,363			(26,605		)
Total revenues	2,452,240			2,491,905
Expenses
Losses and loss expenses	1,242,449			1,920,936
Policy acquisition costs	413,579			429,509
General and administrative expenses	323,061			282,183
Share compensation expenses	30,750			35,427
Transaction expenses	—			17,433
Finance expenses	64,306			66,485
Total expenses	2,074,145			2,751,973
Income before taxes and income from operating affiliates	378,095			(260,068		)
Tax (expense)	(3,385		)	(773		)
Income (loss) from operating affiliates	12,868			(922		)
Net income (loss) from continuing operations	$	387,578		$	(261,763	)
Net income (loss) from discontinued operations, net of taxes	19,366			(21,662		)
Net income (loss)	$	406,944		$	(283,425	)
Net loss (income) attributable to noncontrolling interest	14,685			(24,515		)
Net income (loss) available (attributable) to Validus	$	421,629		$	(307,940	)
Basic earnings (loss) per share	$	3.73		$	(3.20	)
Earnings (loss) per diluted share	$	3.62		$	(3.20	)
The following selected audited information has been provided to present a summary of the results of Flagstone that have been included within the Validus Re segment in the Consolidated Financial Statements for the year ended December 31, 2012.
	From Acquisition Date to
	31-Dec-12
Net premiums written	$	11,305
Total revenue	26,778
Total expenses	(17,061		)
Net income	$	9,717

Goodwill_and_other_intangible_

Goodwill and other intangible assets	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and other intangible assets	Goodwill and other intangible assets
	Following the acquisition of Western World on October 2, 2014, the Company recorded intangible assets for State Licenses, Brand Name, Distribution Network and Technology (including certain amortization thereon) and goodwill. Brand Name and Distribution Network were estimated to have finite useful economic lives of 10 years on acquisition and are being amortized on a straight line basis over such period. Technology was estimated to have a finite useful economic life of 5 years on acquisition and is being amortized on a straight line basis over such period. Indefinite-lived intangible assets recognized in conjunction with the acquisition consist of State Licenses that provide a legal right to transact insurance business in those jurisdictions indefinitely.
	Following the acquisition of Flagstone on November 30, 2012, the Company recorded intangible assets (including certain amortization thereon) and a gain on bargain purchase, net of expenses. Intangible assets of $5,997 were recognized in the Validus Re segment as a result of the Flagstone Acquisition (relating to customer relationships and brand name). As of December 31, 2012, the customer relationships and brand name intangible assets have been fully amortized as they were not expected to significantly contribute to the Company’s future cash flows beyond December 31, 2012.
	Following the acquisition of Talbot Holdings Ltd. on July 2, 2007, the Company recorded intangible assets for Syndicate Capacity, Trademark and Distribution Network (including certain amortization thereon) and goodwill. Syndicate Capacity represents Talbot’s authorized premium income limit to write insurance business in the Lloyd’s market. Talbot has owned 100% of Syndicate 1183’s capacity since 2002 and there are no third party tenure rights. The capacity is renewed annually at no cost to Talbot, but may be freely purchased or sold, subject to Lloyd’s approval. The ability to write insurance business under the syndicate capacity is indefinite with the premium income limit being set yearly by Talbot, subject to Lloyd’s approval. Trademark and Distribution Network were estimated to have finite useful economic lives of 10 years on acquisition and are being amortized on a straight line basis over such periods. Syndicate Capacity and goodwill are estimated to have indefinite useful lives. Goodwill includes amounts related to the value of the workforce.
	The following table shows an analysis of goodwill by segment:
		Talbot		Western World			Total
	Goodwill at December 31, 2012	$	20,393	$	—		$	20,393
	Acquired during the year	—		—			—
	Goodwill at December 31, 2013	$	20,393	$	—		$	20,393
	Acquired during the year	—		175,504			175,504
	Goodwill at December 31, 2014	$	20,393	$	175,504		$	195,897
	There was no accumulated impairment loss at any of the dates indicated.
	The gross carrying value and accumulated amortization of intangible assets by type at December 31, 2014 and 2013 are as follows:
		As of December 31, 2014					As of December 31, 2013
		Gross Carrying Amount		Accumulated Amortization			Gross Carrying Amount		Accumulated Amortization
	Finite-lived intangible assets
	Trade name and customer relationships	$	18,189	$	(10,971	)	$	12,433	$	(10,183	)
	Distribution network	39,831		(26,500		)	35,180		(22,866		)
	Technology	2,323		(116		)	—		—
	Total	$	60,343	$	(37,587	)	$	47,613	$	(33,049	)
	Indefinite-lived intangible assets
	Syndicate capacity	$	91,843	n/a			$	91,843	n/a
	State licenses	12,325		n/a			—		n/a
	Total	$	104,168				$	91,843
	Amortization expense was $4,538, $4,162, and $10,159 for the years ended December 31, 2014, 2013 and 2012, respectively.
	The estimated remaining amortization expense for the finite-lived intangible assets is as follows:
		Total
	2015	$	5,663
	2016	5,663
	2017	3,579
	2018	1,501
	2019 and thereafter	6,350
		$	22,756
	As described in Note 3(n) "Goodwill and other intangible assets," the Company performed an assessment and it was determined that it was more likely than not that neither goodwill or the indefinite-lived intangible assets were impaired. The factors assessed in making this determination included the overall insurance industry outlook, business strategy, premium rates, earnings sustainability, market capitalization and the regulatory and political environment.

Investments

Investments	12 Months Ended
	Dec. 31, 2014
Investments [Abstract]
Investments	Investments
	(a)	Fixed maturity, short-term and other investments
	The Company's investments in fixed maturities, short-term investments and other investments are classified as trading and carried at fair value, with related net unrealized gains or losses included in earnings.
	The amortized cost (or cost), gross unrealized gains and (losses) and estimated fair value of investments at December 31, 2014 were as follows:
		Amortized Cost or Cost			Gross Unrealized Gains				Gross Unrealized Losses				Estimated Fair Value
	U.S. government and government agency	$	759,232		$	1,755			$	(901	)		$	760,086
	Non-U.S. government and government agency	279,493			1,215				(1,980		)		278,728
	U.S. states, municipalities and political subdivisions	448,668			1,780				(825		)		449,623
	Agency residential mortgage-backed securities	520,685			9,697				(1,151		)		529,231
	Non-agency residential mortgage-backed securities	37,954			369				(516		)		37,807
	U.S. corporate	1,500,963			3,960				(5,217		)		1,499,706
	Non-U.S. corporate	564,386			2,765				(3,989		)		563,162
	Bank loans	457,537			200				(8,733		)		449,004
	Catastrophe bonds	75,822			768				(926		)		75,664
	Asset-backed securities	647,422			1,250				(1,190		)		647,482
	Commercial mortgage-backed securities	242,332			598				(692		)		242,238
	Total fixed maturities	5,534,494			24,357				(26,120		)		5,532,731
	Total short-term investments (a)	1,051,222			13				(161		)		1,051,074
	Other investments
	Fund of hedge funds	2,570			125				(920		)		1,775
	Preferred stock	6,535			—				(201		)		6,334
	Hedge funds (b)	570,371			60,792				(134,203		)		496,960
	Private equity investments	48,995			4,987				(611		)		53,371
	Investment funds	244,506			437				(111		)		244,832
	Mutual funds	6,199			3,540				—				9,739
	Total other investments	879,176			69,881				(136,046		)		813,011
	Total investments including assets held in trust, catastrophe bonds and noncontrolling interest	$	7,464,892		$	94,251			$	(162,327	)		$	7,396,816
	Assets held in trust on behalf of operating affiliates (a)	$	(732,782	)	$	—			$	—			$	(732,782	)
	Catastrophe bonds	$	(75,822	)	$	(768	)		$	926			$	(75,664	)
	Noncontrolling interest (b)	$	(502,830	)	$	(48,446	)		$	120,782			$	(430,494	)
	Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	$	6,153,458		$	45,037			$	(40,619	)		$	6,157,876
	(a)	Included in the short-term investments balance are assets held in trust to support AlphaCat's fully collateralized reinsurance transactions. Also, included in the short-term investments balance are investments held by one AlphaCat ILS fund which is consolidated by the Company but in which the Company has an equity interest of less than 100%. The remaining interests are held by third party investors and included in the Consolidated Balance Sheets as redeemable noncontrolling interest.
	(b)	Included in the hedge funds balance are investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and included in the Consolidated Balance Sheets as noncontrolling interest.
	The amortized cost (or cost), gross unrealized gains and (losses) and estimated fair value of investments at December 31, 2013 were as follows:
		Amortized Cost or Cost			Gross Unrealized Gains				Gross Unrealized Losses				Estimated Fair Value
	U.S. government and government agency	$	1,368,826		$	2,589			$	(6,736	)		$	1,364,679
	Non-U.S. government and government agency	454,578			6,511				(2,021		)		459,068
	U.S. states, municipalities and political subdivisions	42,978			459				(317		)		43,120
	Agency residential mortgage-backed securities	305,450			8,310				(2,261		)		311,499
	Non-agency residential mortgage-backed securities	16,530			143				(914		)		15,759
	U.S. corporate	1,328,960			9,208				(5,684		)		1,332,484
	Non-U.S. corporate	711,581			5,917				(3,173		)		714,325
	Bank loans	712,859			5,659				(1,402		)		717,116
	Catastrophe bonds	72,000			2,551				—				74,551
	Asset-backed securities	509,091			1,409				(843		)		509,657
	Total fixed maturities	5,522,853			42,756				(23,351		)		5,542,258
	Total short-term investments (a)	787,670			45				(1		)		787,714
	Other investments
	Fund of hedge funds	3,141			83				(921		)		2,303
	Hedge funds (b)	584,518			71,641				(95,076		)		561,083
	Private equity investments	12,333			1,410				(258		)		13,485
	Investment funds	117,307			92				—				117,399
	Mutual funds	6,199			3,617				—				9,816
	Total other investments	723,498			76,843				(96,255		)		704,086
	Total investments including assets held in trust, catastrophe bonds and noncontrolling interest	$	7,034,021		$	119,644			$	(119,607	)		$	7,034,058
	Assets held in trust on behalf of operating affiliates (a)	$	(651,715	)	$	—			$	—			$	(651,715	)
	Catastrophe bonds	$	(53,000	)	$	(2,544	)		$	—			$	(55,544	)
	Noncontrolling interest (b)	$	(512,121	)	$	(62,850	)		$	85,569			$	(489,402	)
	Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	$	5,817,185		$	54,250			$	(34,038	)		$	5,837,397
	(a)	Included in the short-term investments balance are assets held in trust to support AlphaCat's fully collateralized reinsurance transactions. Also, included in the short-term investments balance are investments held by two AlphaCat ILS funds which are consolidated by the Company but in which the Company has an equity interest of less than 100%. The remaining interests are held by third party investors and included in the Consolidated Balance Sheets as redeemable noncontrolling interest.
	(b)	Included in the hedge funds balance are investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and included in the Consolidated Balance Sheets as noncontrolling interest.
	As of June 30, 2014, the Company changed the methodology of assigning investment ratings to its fixed maturities portfolio. In prior periods, investment ratings were the lower of Moody’s or Standard & Poor’s rating for each investment security, presented in Standard & Poor’s equivalent rating. As of June 30, 2014, investment ratings are the median of Moody’s, Standard & Poor’s and Fitch, presented in Standard & Poor’s equivalent rating. For investments where only two ratings are available, the lower of the two ratings shall apply, presented in Standard & Poor’s equivalent rating. For investments where Moody’s and Standard & Poor’s ratings are not available, Fitch ratings are used and presented in Standard & Poor’s equivalent rating. The December 31, 2013 comparative data was restated as a result, to conform to current period presentation.
	The following table sets forth information regarding the investment ratings of the Company’s fixed maturities portfolio as at December 31, 2014 and 2013.
		December 31, 2014						December 31, 2013
	Estimated Fair Value			% of Total			Estimated Fair Value				% of Total
AAA	$	2,494,239		45.1	%		$	2,510,781			45.3	%
AA	848,226			15.4	%		696,998				12.6	%
A	1,086,091			19.6	%		1,233,716				22.3	%
BBB	505,208			9.1	%		323,085				5.8	%
Total investment-grade fixed maturities	4,933,764			89.2	%		4,764,580				86	%
BB	362,972			6.6	%		354,992				6.4	%
B	145,240			2.6	%		383,639				6.9	%
CCC	12,733			0.2	%		2,453				—	%
CC	3,926			0.1	%		2,496				0.1	%
C	1,344			—	%		235				—	%
D/NR	72,752			1.3	%		33,863				0.6	%
Total non-investment grade fixed maturities	598,967			10.8	%		777,678				14	%
Total fixed maturities	$	5,532,731		100	%		$	5,542,258			100	%
The amortized cost and estimated fair value amounts for fixed maturity securities held at December 31, 2014 and 2013 are shown below by contractual maturity. Actual maturity may differ from contractual maturity because certain borrowers may have the right to call or prepay certain obligations with or without call or prepayment penalties.
	December 31, 2014							December 31, 2013
	Amortized Cost			Estimated Fair Value				Amortized Cost				Estimated Fair Value
Due in one year or less	$	312,843		$	313,248			$	688,855			$	692,768
Due after one year through five years	3,163,225			3,159,200				3,603,459				3,613,847
Due after five years through ten years	497,175			491,870				396,389				395,633
Due after ten years	112,858			111,655				3,079				3,095
	4,086,101			4,075,973				4,691,782				4,705,343
Asset-backed and mortgage-backed securities	1,448,393			1,456,758				831,071				836,915
Total fixed maturities	$	5,534,494		$	5,532,731			$	5,522,853			$	5,542,258
(b)	Net investment income
Net investment income was derived from the following sources:
	Year Ended
	December 31, 2014			December 31, 2013				December 31, 2012
Fixed maturities and short-term investments	$	97,248		$	99,216			$	105,937
Other investments	5,111			—				2,790
Restricted cash and cash and cash equivalents	5,178			4,713				7,259
Securities lending income	11			6				14
Total gross investment income	107,548			103,935				116,000
Investment expenses	(7,472		)	(7,863		)		(8,064		)
Total net investment income	$	100,076		$	96,072			$	107,936
Net investment income from other investments includes distributed and undistributed net income from certain investment funds.
(c)	Net realized gains (losses) and change in net unrealized (losses) gains on investments
The following represents an analysis of net realized gains (losses) and the change in net unrealized (losses) gains on investments:
	Year Ended
	December 31, 2014			December 31, 2013				December 31, 2012
Fixed maturities, short-term and other investments
Gross realized gains (a)	$	31,316		$	31,402			$	38,905
Gross realized (losses)	(8,221		)	(28,144		)		(20,672		)
Net realized gains on investments	23,095			3,258				18,233
Change in net unrealized (losses) gains on investments (a)	(57,973		)	(58,481		)		17,585
Total net realized and change in net unrealized (losses) gains on investments including assets held in trust, catastrophe bonds and noncontrolling interest	(34,878		)	(55,223		)		35,818
Assets held in trust on behalf of operating affiliates	—			88				(88		)
Catastrophe bonds	2,702			(2,258		)		416
Noncontrolling interest (a)	42,258			1,836				17,263
Total net realized and change in net unrealized (losses) gains on investments excluding assets held in trust, catastrophe bonds and noncontrolling interest	$	10,082		$	(55,557	)		$	53,409
(a)	Includes change in net unrealized gains (losses) and realized gains on investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and is included in the Consolidated Statements of Comprehensive Income as net loss (income) attributable to noncontrolling interest.
(d)	Pledged investments
The following tables outline investments pledged as collateral under the Company's credit and other facilities. For further details of the facilities, please refer to Note 19: “Debt and financing arrangements”:
		December 31, 2014
Description		Commitment			Issued and Outstanding				Investments pledged as collateral
$400,000 syndicated unsecured letter of credit facility		$	400,000		$	—			$	—
$525,000 syndicated secured letter of credit facility		525,000			276,455				395,750
$200,000 secured bi-lateral letter of credit facility		200,000			15,649				35,645
Talbot FAL facility		25,000			25,000				31,048
PaCRe senior secured letter of credit facility		10,000			294				—
AlphaCat Re secured letter of credit facility		30,000			30,000				30,078
IPC bi-lateral facility		40,000			15,897				99,437
$375,000 Flagstone bi-lateral facility		375,000			198,389				430,782
		$	1,605,000		$	561,684			$	1,022,740
		December 31, 2013
Description		Commitment			Issued and Outstanding				Investments pledged as collateral
$400,000 syndicated unsecured letter of credit facility		$	400,000		$	—			$	—
$525,000 syndicated secured letter of credit facility		525,000			358,567				507,620
$200,000 secured bi-lateral letter of credit facility		200,000			16,726				130,256
Talbot FAL facility		25,000			25,000				30,801
PaCRe senior secured letter of credit facility		10,000			294				—
AlphaCat Re secured letter of credit facility		24,800			24,800				24,806
IPC bi-lateral facility		40,000			20,177				98,465
$375,000 Flagstone bi-lateral facility		375,000			305,686				454,458
		$	1,599,800		$	751,250			$	1,246,406
In addition, $3,285,692 of cash and cash equivalents, restricted cash, short-term investments and fixed maturities were pledged during the normal course of business as at December 31, 2014 (2013: $2,991,322). Of those, $3,233,872 were held in trust (2013: $2,982,152). Pledged assets are generally for the benefit of the Company's cedants and policyholders, to support AlphaCat's fully collateralized reinsurance transactions and to facilitate the accreditation of Talbot as an alien insurer/reinsurer by certain regulators.
(e)	Securities lending
The Company participates in a securities lending program whereby certain securities from its portfolio are loaned to third parties for short periods of time through a lending agent. The Company retains all economic interest in the securities it lends and receives a fee from the borrower for the temporary use of the securities. Collateral in the form of cash, government securities and letters of credit is required at a rate of 102% of the market value of the loaned securities and is held by a third party.

Fair_value_measurements

Fair value measurements	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Fair value measurements	Fair value measurements
	(a)	Classification within the fair value hierarchy
	Fair value is defined as the price to sell an asset or transfer a liability in an orderly transaction between market participants. Under U.S. GAAP, a company must determine the appropriate level in the fair value hierarchy for each fair value measurement. The fair value hierarchy prioritizes the inputs, which refer broadly to assumptions market participants would use in pricing an asset or liability, into three levels. It gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. The level in the fair value hierarchy within which a fair value measurement in its entirety falls is determined based on the lowest level input that is significant to the fair value measurement in its entirety.
	The three levels of the fair value hierarchy are described below:
	Level 1 - Fair values are measured based on unadjusted quoted prices in active markets for identical assets or liabilities that we have the ability to access.
	Level 2 - Fair values are measured based on quoted prices in active markets for similar assets or liabilities, quoted prices for identical assets or liabilities in inactive markets, or for which significant inputs are observable (e.g., interest rates, yield curves, prepayment speeds, default rates, loss severities, etc.) or can be corroborated by observable market data.
	Level 3 - Fair values are measured based on inputs that are unobservable and significant to the overall fair value measurement. The unobservable inputs reflect the Company's own judgments about assumptions where there is little, if any, market activity for that asset or liability that market participants might use.
	The availability of observable inputs can vary from financial instrument to financial instrument and is affected by a wide variety of factors including, for example, the type of financial instrument, whether the financial instrument is new and not yet established in the marketplace, and other characteristics particular to the instrument. To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires significantly more judgment.
	Accordingly, the degree of judgment exercised by management in determining fair value is greatest for instruments categorized in Level 3. In periods of market dislocation, the observability of prices and inputs may be reduced for many instruments. This may lead the Company to change the selection of our valuation technique (for example, from market to cash flow approach) or to use multiple valuation techniques to estimate the fair value of a financial instrument. These circumstances could cause an instrument to be reclassified between levels within the fair value hierarchy.
	There have been no material changes in the Company's valuation techniques during the period, or periods, represented by these Consolidated Financial Statements. The following methods and assumptions were used in estimating the fair value of each class of financial instrument recorded in the Consolidated Balance Sheets.
	At December 31, 2014, the Company’s investments were allocated between Levels 1, 2 and 3 as follows:
		Level 1			Level 2			Level 3			Total
	U.S. government and government agency	$	—		$	760,086		$	—		$	760,086
	Non-U.S. government and government agency	—			278,728			—			278,728
	U.S. states, municipalities and political subdivisions	—			449,623			—			449,623
	Agency residential mortgage-backed securities	—			529,231			—			529,231
	Non-agency residential mortgage-backed securities	—			37,807			—			37,807
	U.S. corporate	—			1,499,706			—			1,499,706
	Non-U.S. corporate	—			563,162			—			563,162
	Bank loans	—			416,256			32,748			449,004
	Catastrophe bonds	—			70,664			5,000			75,664
	Asset-backed securities	—			647,482			—			647,482
	Commercial mortgage-backed securities	—			242,238			—			242,238
	Total fixed maturities	—			5,494,983			37,748			5,532,731
	Total short-term investments (a)	942,716			108,358			—			1,051,074
	Other investments
	Fund of hedge funds	—			—			1,775			1,775
	Preferred stock	—			6,334			—			6,334
	Hedge funds (b)	—			—			496,960			496,960
	Private equity investments	—			—			53,371			53,371
	Investment funds	—			140,045			104,787			244,832
	Mutual funds	—			9,739			—			9,739
	Total other investments	—			156,118			656,893			813,011
	Total investments including assets held in trust, catastrophe bonds and noncontrolling interest	$	942,716		$	5,759,459		$	694,641		$	7,396,816
	Assets held in trust on behalf of operating affiliates (a)	$	(732,782	)	$	—		$	—		$	(732,782	)
	Catastrophe bonds	$	—		$	(70,664	)	$	(5,000	)	$	(75,664	)
	Noncontrolling interest (b)	$	—		$	—		$	(430,494	)	$	(430,494	)
	Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	$	209,934		$	5,688,795		$	259,147		$	6,157,876
	(a)	Included in the short-term investments balance are assets held in trust to support AlphaCat's fully collateralized reinsurance transactions. Also, included in the short-term investments balance are investments held by one AlphaCat ILS fund which is consolidated by the Company but in which the Company has an equity interest of less than 100%. The remaining interests are held by third party investors and included in the Consolidated Balance Sheets as redeemable noncontrolling interest.
	(b)	Included in the hedge funds balance are investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and included in the Consolidated Balance Sheets as noncontrolling interest.
	At December 31, 2013, the Company’s investments were allocated between Levels 1, 2 and 3 as follows:
		Level 1			Level 2			Level 3			Total
	U.S. government and government agency	$	—		$	1,364,679		$	—		$	1,364,679
	Non-U.S. government and government agency	—			459,068			—			459,068
	U.S. states, municipalities and political subdivisions	—			43,120			—			43,120
	Agency residential mortgage-backed securities	—			311,499			—			311,499
	Non-agency residential mortgage-backed securities	—			15,759			—			15,759
	U.S. corporate	—			1,332,484			—			1,332,484
	Non-U.S. corporate	—			714,325			—			714,325
	Bank loans	—			717,116			—			717,116
	Catastrophe bonds	—			74,551			—			74,551
	Asset-backed securities	—			509,657			—			509,657
	Total fixed maturities	—			5,542,258			—			5,542,258
	Total short-term investments (a)	783,151			4,563			—			787,714
	Other investments
	Fund of hedge funds	—			—			2,303			2,303
	Hedge funds (b)	—			—			561,083			561,083
	Private equity investments	—			—			13,485			13,485
	Investment fund	—			117,399			—			117,399
	Mutual funds	—			9,816			—			9,816
	Total other investments	—			127,215			576,871			704,086
	Total investments including assets held in trust, catastrophe bonds and noncontrolling interest	$	783,151		$	5,674,036		$	576,871		$	7,034,058
	Assets held in trust on behalf of operating affiliates (a)	$	(651,715	)	$	—		$	—		$	(651,715	)
	Catastrophe bonds	$	—		$	(55,544	)	$	—		$	(55,544	)
Noncontrolling interest (b)	$	—		$	—		$	(489,402	)	$	(489,402	)
Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	$	131,436		$	5,618,492		$	87,469		$	5,837,397
(a)	Included in the short-term investments balance are assets held in trust to support AlphaCat's fully collateralized reinsurance transactions. Also, included in the short-term investments balance are investments held by two AlphaCat ILS funds which are consolidated by the Company but in which the Company has an equity interest of less than 100%. The remaining interests are held by third party investors and included in the Consolidated Balance Sheets as redeemable noncontrolling interest.
(b)	Included in the Hedge funds balance are investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and included in the Consolidated Balance Sheets as noncontrolling interest.
At December 31, 2014, Level 3 investments excluding assets held in trust on behalf of operating affiliates, catastrophe bonds and noncontrolling interests totaled $259,147 (December 31, 2013: $87,469), representing 4.2% (December 31, 2013: 1.5%) of total investments, excluding assets held in trust on behalf of operating affiliates, catastrophe bonds and noncontrolling interests, measured at fair value on a recurring basis.
(b)	Level 1 assets measured at fair value
Short term investments
Short term investments categorized as Level 1 consist primarily of highly liquid securities, all with maturities less than one year from the date of purchase. The fair value of the Company's portfolio of short term investments are generally determined using amortized cost which approximates fair value. The Company has determined that certain of its short-term investments, held in highly liquid money market-type funds, should be included in Level 1 as their fair values are based on quoted market prices in active markets.
(c)	Level 2 assets measured at fair value
Fixed maturity investments
Fixed maturity investments included in Level 2 include U.S. government and government agency, non-U.S. government and government agency, U.S. states, municipalities and political subdivisions, agency residential mortgage-backed securities, non-agency residential mortgage-backed securities, U.S. corporate, non-U.S. corporate, bank loans, catastrophe bonds, asset-backed securities and commercial mortgage-backed securities.
In general, valuation of the Company's fixed maturity investment portfolios is provided by pricing services, such as index providers and pricing vendors, as well as broker quotations. The pricing vendors provide valuations for a high volume of liquid securities that are actively traded. For securities that do not trade on an exchange, the pricing services generally utilize market data and other observable inputs in matrix pricing models to determine month end prices. Prices are generally verified using third party data. Securities which are priced by an index provider are generally included in the index.
In general, broker-dealers value securities through their trading desks based on observable inputs. The methodologies include mapping securities based on trade data, bids or offers, observed spreads, and performance on newly issued securities. Broker-dealers also determine valuations by observing secondary trading of similar securities. Prices obtained from broker quotations are considered non-binding, however they are based on observable inputs and by observing secondary trading of similar securities obtained from active, non-distressed markets.
The Company considers these Level 2 inputs as they are corroborated with other market observable inputs. The techniques generally used to determine the fair value of the Company's fixed maturity investments are detailed below by asset class.
U.S. government and government agency
U.S. government and government agency securities consist primarily of debt securities issued by the U.S. Treasury and mortgage pass-through agencies such as the Federal National Mortgage Association, the Federal Home Loan Mortgage Corporation and the Government National Mortgage Association. Fixed maturity investments included in U.S. government and government agency securities are primarily priced by pricing services. When evaluating these securities, the pricing services gather information from market sources and integrate other observations from markets and sector news. Evaluations are updated by obtaining broker dealer quotes and other market information including actual trade volumes, when available. The fair value of each security is individually computed using analytical models which incorporate option adjusted spreads and other daily interest rate data.
Non-U.S. government and government agency
Non-U.S. government and government agency securities consist of debt securities issued by non-U.S. governments and their agencies along with supranational organizations (also known as sovereign debt securities). Securities held in these sectors are primarily priced by pricing services who employ proprietary discounted cash flow models to value the securities. Key quantitative inputs for these models are daily observed benchmark curves for treasury, swap and high issuance credits. The pricing services then apply a credit spread for each security which is developed by in-depth and real time market analysis. For securities in which trade volume is low, the pricing services utilize data from more frequently traded securities with similar attributes. These models may also be supplemented by daily market and credit research for international markets.
U.S. states, municipalities and political subdivisions
The Company's U.S. states, municipalities and political subdivisions portfolio contains debt securities issued by U.S. domiciled state and municipal entities. These securities are generally priced by independent pricing services using the techniques described for U.S. government and government agency securities described above.
Agency residential mortgage-backed securities
The Company's agency residential mortgage-backed investments are primarily priced by pricing services using a mortgage pool specific model which utilizes daily inputs from the active to be announced ("TBA") market which is very liquid, as well as the U.S. treasury market. The model also utilizes additional information, such as the weighted average maturity, weighted average coupon and other available pool level data which is provided by the sponsoring agency. Valuations are also corroborated with daily active market quotes.
Non-agency residential mortgage-backed securities
The Company's non-agency mortgage-backed investments include non-agency prime residential mortgage-backed fixed maturity investments. The Company has no fixed maturity investments classified as sub-prime held in its fixed maturity investments portfolio. Securities held in these sectors are primarily priced by pricing services using an option adjusted spread model or other relevant models, which principally utilize inputs including benchmark yields, available trade information or broker quotes, and issuer spreads. The pricing services also review collateral prepayment speeds, loss severity and delinquencies among other collateral performance indicators for the securities valuation, when applicable.
U.S. corporate
Corporate debt securities consist primarily of investment-grade debt of a wide variety of U.S. corporate issuers and industries. The Company's corporate fixed maturity investments are primarily priced by pricing services. When evaluating these securities, the pricing services gather information from market sources regarding the issuer of the security and obtain credit data, as well as other observations, from markets and sector news. Evaluations are updated by obtaining broker dealer quotes and other market information including actual trade volumes, when available. The pricing services also consider the specific terms and conditions of the securities, including any specific features which may influence risk. In certain instances, securities are individually evaluated using a spread which is added to the U.S. treasury curve or a security specific swap curve as appropriate.
Non-U.S. corporate
Non-U.S. corporate debt securities consist primarily of investment-grade debt of a wide variety of non-U.S. corporate issuers and industries. The Company's non-U.S. corporate fixed maturity investments are primarily priced by pricing services. When evaluating these securities, the pricing services gather information from market sources regarding the issuer of the security and obtain credit data, as well as other observations, from markets and sector news. Evaluations are updated by obtaining broker dealer quotes and other market information including actual trade volumes, when available. The pricing services also consider the specific terms and conditions of the securities, including any specific features which may influence risk.
Bank loans
The Company's bank loan investments consist primarily of below-investment-grade debt of a wide variety of corporate issuers and industries. The Company's bank loans are primarily priced by pricing services. When evaluating these securities, the pricing services gather information from market sources regarding the issuer of the security and obtain credit data, as well as other observations, from markets and sector news. Evaluations are updated by obtaining broker dealer quotes and other market information including actual trade volumes, when available. The pricing services also consider the specific terms and conditions of the securities, including any specific features which may influence risk.
Catastrophe bonds
Catastrophe bonds are based on broker or underwriter bid indications. To the extent that these indications are based on significant unobservable inputs, the relevant bonds will be classified as a Level 3 asset.
Asset-backed securities
Asset backed securities include mostly investment-grade debt securities backed by pools of loans with a variety of underlying collateral, including automobile loan receivables, student loans, credit card receivables, and collateralized loan obligations originated by a variety of financial institutions. Securities held in these sectors are primarily priced by pricing services. The pricing services apply dealer quotes and other available trade information such as bids and offers, prepayment speeds which may be adjusted for the underlying collateral or current price data, the U.S. treasury curve and swap curve as well as cash settlement. The pricing services determine the expected cash flows for each security held in this sector using historical prepayment and default projections for the underlying collateral and current market data. In addition, a spread is applied to the relevant benchmark and used to discount the cash flows noted above to determine the fair value of the securities held in this sector.
Commercial mortgage-backed securities
Commercial mortgage backed securities are investment-grade debt primarily priced by pricing services. The pricing services apply dealer quotes and other available trade information such as bids and offers, prepayment speeds which may be adjusted for the underlying collateral or current price data, the U.S. treasury curve and swap curve as well as cash settlement. The pricing services determine the expected cash flows for each security held in this sector using historical prepayment and default projections for the underlying collateral and current market data. In addition, a spread is applied to the relevant benchmark and used to discount the cash flows noted above to determine the fair value of the securities held in this sector.
Short term investments
Short term investments consist primarily of highly liquid securities, all with maturities less than one year from the date of purchase. The fair value of the Company's portfolio of short term investments is generally determined using amortized cost which approximates fair value. The Company has determined that, other than highly liquid money market-type funds, the remaining securities are classified within Level 2 because these securities are typically not actively traded due to their approaching maturity and, as such, their amortized cost approximates fair value.
Preferred stock
The Company's preferred stock portfolio contains preferred term securities typically sold by non public financial services companies, through a collateralized debt obligation product and are classified as Level 2 assets. The fair value of these investments is determined based on quoted market prices in active markets.
Investment funds
Investment funds classified as Level 2 assets includes one pooled investment which is invested in fixed income securities with high credit ratings. The investment fund is only open to Lloyd’s Trust Fund participants. The fair value of units in the investment fund is based on the net asset value of the fund as reported by Lloyd’s Treasury & Investment Management.
Also included within investment funds is the Company's share of a portfolio of Lloyd's overseas deposits, which is also classified as a Level 2 asset. The underlying deposits are managed centrally by Lloyd's and invested according to local regulatory requirements. The composition of the portfolio varies and the deposits are made across the market. The fair value of the deposits is based on the portfolio level reporting that is provided by Lloyd's.
Mutual funds
Mutual funds consist of two investment funds which are invested in various quoted investments. The fair value of units in the mutual funds is based on the net asset value of the fund as reported by the fund manager.
(d)	Level 3 assets measured at fair value
Level 3 includes financial instruments that are valued using market approach and income approach valuation techniques. These models incorporate both observable and unobservable inputs. The Company's hedge funds, a fund of hedge funds, private equity investments, certain bank loans, an investment fund and certain catastrophe bonds are the only financial instruments in this category as at December 31, 2014. For each respective hedge fund investment, the Company obtains and reviews the valuation methodology used by the fund administrators and investment managers to ensure that the hedge fund investments are following fair value principles consistent with U.S. GAAP in determining the net asset value (“NAV”).
Within the hedge fund industry, there is a general lack of transparency necessary to facilitate a detailed independent assessment of the values placed on the securities underlying the NAV provided by the fund manager or fund administrator. To address this, on a quarterly basis, we perform a number of monitoring procedures designed to assist us in the assessment of the quality of the information provided by managers and administrators. These procedures include, but are not limited to, regular review and discussion of each fund's performance with its manager and regular evaluation of fund performance against applicable benchmarks.
Bank loans
Included in the bank loans portfolio is a collection of loan participations held through an intermediary. These investments are classified as Level 3 assets. A third party pricing service provides monthly valuation reports for each loan and participation using a combination of quotations from loan pricing services, leveraged loan indices or market price quotes obtained directly from the intermediary.
Fund of hedge funds
The fund of hedge funds includes a side pocket. While a redemption request has been submitted, the timing of receipt of proceeds on the side pocket is unknown. The fund's administrator provides a monthly reported NAV with a one month delay in its valuation which was used as a basis for fair value measurement in the Company's December 31, 2014 Consolidated Balance Sheet. The fund manager has provided an estimate of the fund NAV at December 31, 2014 based on the estimated performance provided from the underlying funds. To determine the reasonableness of the estimated NAV, the Company compares the one month delayed fund administrator's NAV to the fund manager's estimated NAV that incorporates relevant valuation sources on a timely basis. Material variances are recorded in the current reporting period while immaterial variances are recorded in the following reporting period. As this valuation technique incorporates both observable and significant unobservable inputs, the fund of hedge funds is classified as a Level 3 asset.
Hedge funds
The hedge funds were valued at $496,960 at December 31, 2014 (2013: $561,083). The hedge funds consist of investments in five Paulson & Co. managed funds (the "Paulson hedge funds") and one hedge fund assumed in the acquisition of Flagstone Reinsurance Holdings, S.A. (the "Flagstone Acquisition") (the "Flagstone hedge fund").
The Paulson hedge funds' administrator provides monthly reported NAVs with a one month delay in its valuation which was used as a partial basis for fair value measurement in the Company's December 31, 2014 Consolidated Balance Sheet. The fund manager provides an estimate of the NAV as at December 31, 2014 based on estimated performance. The Company adjusts fair value to the fund manager's estimated NAV that incorporates relevant valuation sources on a timely basis. To determine the reasonableness of the estimated NAV, the Company assesses the variance between the fund manager's estimated NAV and the fund administrator's NAV. Material variances are recorded in the current reporting period while immaterial variances are recorded in the following reporting period. Historically, the Company's valuation estimates have not materially differed from the subsequent NAVs.
The Flagstone hedge fund's administrator provides quarterly NAVs with a three-month delay in valuation which was used as a basis for fair value measurement in the Company's December 31, 2014 Consolidated Balance Sheet.
As these valuation techniques incorporate both observable and significant unobservable inputs, both the Paulson hedge funds and the Flagstone hedge fund are classified as Level 3 assets. The Paulson hedge funds are subject to quarterly liquidity.
Private equity investments
The private equity funds provide quarterly or semi-annual partnership capital statements with a three month or a six month delay which are used as a basis for valuation in the Company's December 31, 2014 Consolidated Balance Sheet. These private equity investments vary in investment strategies and are not actively traded in any open markets. As this valuation technique can incorporate significant unobservable inputs, the private equity investments are classified as Level 3 assets.
Investment funds
Investment funds classified as Level 3 assets consists of one structured securities fund that invests across asset backed securities, residential mortgage backed securities and commercial mortgage backed securities. The fair value of units in the investment fund is based on the NAV of the fund as reported by the independent fund administrator. The fund's administrator provides a monthly reported NAV with a one-month delay in its valuation which was used as a basis for fair value measurement in the Company's December 31, 2014 Consolidated Balance Sheet. As this valuation technique incorporates both observable and significant unobservable inputs, the investment fund investment is classified as a Level 3 asset.
The following table presents a reconciliation of the beginning and ending balances for all investments measured at fair value on a recurring basis using Level 3 inputs during the years ended December 31, 2014 and 2013:
	Total Fair Market Value
	Year Ended December 31, 2014			Year Ended December 31, 2013
Level 3 investments—Beginning of year	$	576,871		$	556,234
Additions to level 3 investments due to Western World acquisition	23,620			—
Purchases	175,129			99,037
Sales	(52,351		)	(82,000		)
Issuances	—			—
Settlements	(1,500		)	—
Realized gains	8,216			6,132
Unrealized losses	(42,047		)	(2,532		)
Transfers into Level 3 during the year	6,703			—
Level 3 investments—End of year	$	694,641		$	576,871
Catastrophe bonds	(5,000		)	—
Noncontrolling interest (a)	(430,494		)	(489,402		)
Level 3 investments excluding noncontrolling interest	$	259,147		$	87,469
(a)	Includes Level 3 investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and included in the Consolidated Balance Sheets as noncontrolling interest.
During the year ended December 31, 2014 there was a transfer of investments from Level 2 into Level 3 of the fair value hierarchy. This transfer was due to a reassessment of the extent of unobservable inputs used in establishing the fair value of certain catastrophe bonds. There were no transfers into or out of Level 3 during the year ended December 31, 2013.
(e)	Financial Instruments Not Carried at Fair Value
U.S. GAAP guidance in relation to the fair value of financial instruments is also applicable to disclosures of financial instruments not carried at fair value, except for certain financial instruments, including insurance contracts and investments in affiliates. The carrying values of cash and cash equivalents (including restricted amounts), accrued investment income, other assets, net payable for investments purchased and accounts payable and accrued expenses approximated their fair values at December 31, 2014, due to their respective short maturities. As these financial instruments are not actively traded, their respective fair values are classified within Level 2.

Investments_in_affiliates

Investments in affiliates	12 Months Ended
	Dec. 31, 2014
Equity Method Investments and Joint Ventures [Abstract]
Investment in affiliates	Investments in affiliates
	The following table presents the Company's investments in affiliates as at December 31, 2014 and 2013:
		31-Dec-14			31-Dec-13
	Investment affiliate	$	63,506		$	34,500
	Operating affiliates	197,977			106,743
	Investments in affiliates	$	261,483		$	141,243
	(a)	Investment affiliate
	Aquiline Financial Services Fund II L.P.
	On December 20, 2011, the Company entered into an Assignment and Assumption Agreement (the "Agreement") with Aquiline Capital Partners LLC, a Delaware limited liability company (the "Assignor") and Aquiline Capital Partners II GP (Offshore) Ltd., a Cayman Islands company limited by shares (the "Aquiline II General Partner") pursuant to which the Company has assumed 100% of the Assignor's interest in Aquiline Financial Services Fund II L.P. (the "Aquiline II Partnership") representing a total capital commitment of $50,000 (the "Aquiline II Commitment"), as a limited partner in the Partnership (the "Transferred Interest"). The Transferred Interest is governed by the terms of an Amended and Restated Exempted Limited Partnership Agreement of the Fund dated January 9, 2013 (the "Aquiline II Limited Partnership Agreement").
	On October 2, 2014, the Company assumed an additional investment in the Aquiline II Partnership as part of the Western World acquisition representing a total capital commitment of $10,000. This interest is governed by the terms of the Aquiline II Limited Partnership Agreement.
	The Partnership provides a quarterly capital account statement, with a three month delay in its valuation, which was used as the basis for calculating the Company's share of partnership income for the period.
	Aquiline Financial Services Fund III L.P.
	On November 7, 2014, the Company, entered into a Subscription Agreement (the "Subscription Agreement") with Aquiline Capital Partners III GP (Offshore) Ltd., a Cayman Islands company limited by shares (the "Aquiline III General Partner") pursuant to which the Company is committing and agreeing to purchase limited partnership or other comparable limited liability equity interests (the "Limited Partnership Interests") in Aquiline Financial Services Fund III L.P., a Cayman Islands exempted limited partnership (the "Aquiline III Partnership"), and/or one or more Alternative Investment Vehicles and Intermediate Entities (together with the Aquiline III Partnership, the "Fund" or the "Entities") with a capital commitment (the "Aquiline III Commitment") in an amount equal to $100,000, as a limited partner in the Aquiline III Partnership. The Limited Partnership Interests are governed by the terms of an Amended and Restated Exempted Limited Partnership Agreement dated as of November 7, 2014 (the “Aquiline III Limited Partnership Agreement”).
	The Partnership provides a quarterly capital account statement, with a three month delay in its valuation, which was used as the basis for calculating the Company's share of partnership income for the period.
	The following table presents a reconciliation of the beginning and ending investments in the Company’s investment affiliate balances for the years ended December 31, 2014 and 2013:
		Year Ended December 31, 2014			Year Ended December 31, 2013
	Investment in affiliate, beginning of year	$	34,500		$	15,218
	Addition due to Western World acquisition	8,127			—
	Capital contributions	12,468			14,492
	Income from investment affiliate	8,411			4,790
	Investment in affiliate, end of year	$	63,506		$	34,500
	The following table presents the Company’s investment in the Partnership as at December 31, 2014:
		Investment at cost			Voting ownership %			Equity ownership %			Carrying value
	Aquiline Financial Services Fund II L.P.	$	51,001		—	%		8.1	%		$	63,506
	The following table presents the Company’s investment in the Partnership as at December 31, 2013:
		Investment at cost			Voting ownership %			Equity ownership %			Carrying value
	Aquiline Financial Services Fund II L.P.	$	32,110		—	%		6.7	%		$	34,500
	(b)	Operating affiliates
	AlphaCat Re 2011 Ltd.
	On May 25, 2011, the Company joined with other investors in capitalizing AlphaCat Re 2011 Ltd. ("AlphaCat Re 2011"), a special purpose reinsurer formed for the purpose of writing collateralized reinsurance and retrocessional reinsurance. AlphaCat Re 2011 was a market facing entity and the Company's investment in AlphaCat Re 2011 has been treated as an equity method investment.
	AlphaCat Re 2011 is now considered "off-risk" as the risk periods for all reinsurance contracts written have expired. As a result, partial returns of investment have been made to the investors of AlphaCat Re 2011.The Company's portion of the returns made during the years ended December 31, 2014 and 2013 are included in the tables below.
	AlphaCat Re 2012 Ltd.
	On May 29, 2012, the Company joined with other investors in capitalizing AlphaCat Re 2012 Ltd. ("AlphaCat Re 2012"), a special purpose reinsurer formed for the purpose of writing collateralized reinsurance with a particular focus on windstorm risks for Florida domiciled insurance companies. AlphaCat Re 2012 was a market facing entity and the Company's investment in AlphaCat Re 2012 has been treated as an equity method investment.
	AlphaCat Re 2012 is now considered "off-risk" as the risk periods for all reinsurance contracts written have expired. As a result, partial returns of investment have been made to the investors of AlphaCat Re 2012.The Company's portion of the returns made during the years ended December 31, 2014 and 2013 are included in the tables below.
	AlphaCat 2013, Ltd.
	On December 17, 2012, the Company joined with other investors in capitalizing AlphaCat 2013, Ltd. ("AlphaCat 2013"), an entity formed for the purpose of investing in collateralized reinsurance and retrocession on a worldwide basis. AlphaCat 2013 deployed its capital through transactions entered into by AlphaCat Reinsurance Ltd. ("AlphaCat Re") and the Company's investment in AlphaCat 2013 has been treated as an equity method investment.
	AlphaCat 2013 is now considered "off-risk" as the risk periods for all risk-linked instruments have expired. As a result, partial returns of investment have been made to the investors of AlphaCat 2013. The Company's portion of the returns made during the years ended December 31, 2014 and 2013 are included in the tables below.
	AlphaCat 2014, Ltd.
	On December 20, 2013, the Company joined with other investors in capitalizing AlphaCat 2014, Ltd. ("AlphaCat 2014"), an entity formed for the purpose of investing in collateralized reinsurance and retrocessional contracts for the January 1, 2014 renewal season. AlphaCat 2014 deploys its capital through transactions entered into by AlphaCat Re and the Company's investment in AlphaCat 2014 has been treated as an equity method investment.
	AlphaCat 2015, Ltd.
	On December 29, 2014, the Company joined with other investors in capitalizing AlphaCat 2015, Ltd. ("AlphaCat 2015"), an entity formed for the purpose of investing in collateralized reinsurance and retrocessional contracts for the January 1, 2015 renewal season. AlphaCat 2015 deploys its capital through transactions entered into by AlphaCat Re and the Company's investment in AlphaCat 2015 has been treated as an equity method investment.
	AlphaCat ILS funds
	The AlphaCat ILS funds invest in instruments with returns linked to property catastrophe reinsurance, retrocession and insurance linked securities ("ILS") contracts. AlphaCat ILS funds primarily deploy their capital through the AlphaCat Master Fund Ltd. (the "AlphaCat Master Fund") and AlphaCat Re. All of the funds are variable interest entities, with one being consolidated by the Company as the primary beneficiary and the remaining funds being accounted for as equity method investments because the Company holds an equity interest of less than 50% and has significant influence. One of these funds had been consolidated by the Company as the primary beneficiary from its formation through to December 31, 2013. However, on January 1, 2014 the fund received $35,000 in additional third party subscriptions, resulting in a reduction of the Company’s equity interest below 50%. Since the Company retained significant influence, this fund was deconsolidated and accounted for as an equity method investment from January 1, 2014. The fair value of the retained interest, based on the fair value of the underlying instruments in AlphaCat Master Fund and AlphaCat Re, amounted to $113,455 as at January 1, 2014. The deconsolidation resulted in a gain of $1,372 which is included in the Consolidated Statements of Comprehensive Income as other insurance related income for the year ended December 31, 2014. The Company's maximum exposure to any of the funds is the amount of capital invested at any given time.
	AlphaCat Master Fund Ltd. and AlphaCat Reinsurance Ltd.
	The Company utilizes AlphaCat Master Fund and AlphaCat Re for the purpose of investing in capital market products and writing collateralized reinsurance, respectively, on behalf of certain entities within the AlphaCat operating segment. AlphaCat Master Fund and AlphaCat Re are market facing entities which enter into transactions on behalf of AlphaCat 2013, AlphaCat 2014, AlphaCat 2015 and the AlphaCat ILS funds. The Company owns all of the voting equity interest in AlphaCat Master Fund and AlphaCat Re and, as a result, their financial statements are included in the Consolidated Financial Statements of the Company.
	BetaCat ILS funds
	The BetaCat ILS funds invest exclusively in catastrophe bonds (principal-at-risk variable rate notes and other event-linked securities, being referred to collectively as “Cat Bonds”) focused on property and casualty risk issued under Rule 144A of the Securities Act of 1933, following a passive buy-and-hold investment strategy. One of the funds is a variable interest entity and is consolidated by the Company as the primary beneficiary. The remaining fund is consolidated by the Company as it owns all of the voting equity interest. The Company's maximum exposure to either of the funds is the amount of capital invested at any given time. As at December 31, 2014, no third party subscriptions had been received.
	The following tables present a reconciliation of the beginning and ending investment in operating affiliates for the years ended December 31, 2014 and 2013:
		Year Ended December 31, 2014
		AlphaCat Re 2011			AlphaCat Re 2012				AlphaCat 2013				AlphaCat 2014			AlphaCat 2015		AlphaCat ILS funds			Total
	As at December 31, 2013	$	9,809		$	1,313			$	51,744			$	21,982		$	—	$	21,895		$	106,743
	Purchase of shares	—			—				—				—			25,600		12,000			37,600
	Gain on redemption of shares	—			—				—				—			—		(5,077		)	(5,077		)
	Return of investment	(5,825		)	(1,516		)		(52,762		)		—			—		(12,364		)	(72,467		)
	Fair value of retained interest on deconsolidation of AlphaCat ILS fund	—			—				—				—			—		113,455			113,455
	Income from operating affiliates	622			938				2,086				6,103			—		7,974			17,723
	As at December 31, 2014	$	4,606		$	735			$	1,068			$	28,085		$	25,600	$	137,883		$	197,977
		Year Ended December 31, 2013
		AlphaCat Re 2011			AlphaCat Re 2012				AlphaCat 2013				AlphaCat 2014			AlphaCat ILS fund		Total
	As at December 31, 2012	$	62,792		$	29,319			$	45,000			$	—		$	20,000	$	157,111
	Purchase of shares	—			—				—				22,000			—		22,000
	Return of investment	(54,914		)	(31,743		)		—				—			—		(86,657		)
	Income (loss) from operating affiliates	1,931			3,737				6,744				(18		)	1,895		14,289
	As at December 31, 2013	$	9,809		$	1,313			$	51,744			$	21,982		$	21,895	$	106,743
The following table presents the Company's investments in AlphaCat Re 2011, AlphaCat Re 2012, AlphaCat 2013, AlphaCat 2014, AlphaCat 2015 and the AlphaCat ILS funds in the Consolidated Financial Statements as at December 31, 2014:
	Investment in operating affiliates
	Cost			Voting ownership %			Equity ownership %			Carrying value
AlphaCat Re 2011	$	4,606		43.7	%		22.3	%		$	4,606
AlphaCat Re 2012	735			49	%		37.9	%		735
AlphaCat 2013	1,068			40.9	%		19.7	%		1,068
AlphaCat 2014	22,000			42.3	%		19.6	%		28,085
AlphaCat 2015	25,600			40	%		20	%		25,600
AlphaCat ILS funds	133,091			n/a			(a)			137,883
Total	$	187,100								$	197,977
(a)	Equity ownership in the funds was 7.9%, 39.7% and 9.1%, respectively as at December 31, 2014.
The following table presents the Company's investments in AlphaCat Re 2011, AlphaCat Re 2012, AlphaCat 2013, AlphaCat 2014 and the AlphaCat ILS fund in the Consolidated Financial Statements as at December 31, 2013:
	Investment in operating affiliates
	Investment at cost			Voting ownership %			Equity ownership %			Share of net asset value
AlphaCat Re 2011	$	9,882		43.7	%		22.3	%		$	9,809
AlphaCat Re 2012	654			49	%		37.9	%		1,313
AlphaCat 2013	45,000			40.9	%		19.7	%		51,744
AlphaCat 2014	22,000			42.3	%		19.6	%		21,982
AlphaCat ILS fund	20,000			n/a			9.1	%		21,895
Total	$	97,536								$	106,743
The following table presents certain summarized financial information of the AlphaCat entities as at December 31, 2014 and for the year then ended:
	Combined investees summarized financial data
	Total assets			Total liabilities				Total revenue				Net income
AlphaCat Re 2011	$	20,469		$	7,931			$	3			$	2,794
AlphaCat Re 2012	$	3,098		$	1,136			$	—			$	2,477
AlphaCat 2013	$	5,490		$	65			$	14,221			$	10,595
AlphaCat 2014	$	193,702		$	4,102			$	45,333			$	31,070
AlphaCat 2015	$	142,843		$	—			$	—			$	—
AlphaCat ILS funds (a)	$	1,026,222		$	175,376			$	65,320			$	54,421
BetaCat ILS funds	22,010			61				32				(51		)
(a)	AlphaCat ILS funds information includes all funds, including those where the Company is not the primary beneficiary.
(c)	Notes payable and (income) attributable to operating affiliates
Notes are issued during the course of a year by AlphaCat Master Fund and AlphaCat Re to AlphaCat 2013, AlphaCat 2014, AlphaCat 2015 and the AlphaCat ILS funds (collectively the "feeder funds") in order to fund the purchase of capital market products and to write collateralized reinsurance on their behalf. The underlying capital market products and collateralized reinsurance typically have at least a twelve month duration; however, they do not have a stated maturity date. Since repayment is dependent on the settlement of the underlying transactions, the notes are subsequently redeemed as the underlying transactions are settled. The Company’s investments in the feeder funds, together with investments made by third parties, are provided as consideration for these notes to AlphaCat Master Fund and AlphaCat Re, which are consolidated in the Company’s Consolidated Financial Statements. The effective economic interest in AlphaCat Master Fund and AlphaCat Re that results from these transactions is represented on the Consolidated Balance Sheet as notes payable to operating affiliates. The subsequent income or loss generated by the relevant capital market products or collateralized reinsurance is transferred to the operating affiliates as (income) loss attributable to operating affiliate investors in the Company’s Consolidated Statements of Comprehensive Income. The notes do not have any principal amount, since the final amount payable is dependent on the income or loss. To the extent that the (income) loss attributable to operating affiliate investors has not been returned to investors, it is included in accounts payable and accrued expenses in the Consolidated Balance Sheets.
The following tables present a reconciliation of the beginning and ending notes payable to operating affiliates for the year ended December 31, 2014 and 2013:
	Year Ended December 31, 2014
	AlphaCat 2013			AlphaCat 2014				AlphaCat ILS funds				Total
As at December 31, 2013	$	223,809		$	—			$	215,463			$	439,272
Notes payable to operating affiliates recognized on deconsolidation of AlphaCat ILS fund	—			—				178,837				178,837
Issuance of notes payable to operating affiliates	—			157,914				522,113				680,027
Redemption of notes payable to operating affiliates	(223,512		)	—				(393,556		)		(617,068		)
Foreign exchange gains	(297		)	(530		)		(8,776		)		(9,603		)
As at December 31, 2014	$	—		$	157,384			$	514,081			$	671,465
	Year Ended December 31, 2013
	AlphaCat 2013			AlphaCat ILS funds				Total
As at December 31, 2012	$	—		$	—			$	—
Issuance of notes payable to operating affiliates	223,082			218,044				441,126
Redemption of notes payable to operating affiliates	—			(3,553		)		(3,553		)
Foreign exchange losses	727			972				1,699
As at December 31, 2013	$	223,809		$	215,463			$	439,272
The portion of notes payable to operating affiliates that were due to the Company, as an investor in the affiliates, and third party investors as at December 31, 2014 amounted to $148,264 and $523,201, respectively (December 31, 2013: $63,654 and $375,618).
The following table presents the (income) attributable to operating affiliate investors for the year ended December 31, 2014, 2013 and 2012:
	Years Ended
	December 31,			December 31,				December 31,
	2014			2013				2012
AlphaCat 2013	$	(14,577	)	$	(47,329	)		$	—
AlphaCat 2014	(46,100		)	—				—
AlphaCat ILS funds	(48,722		)	(21,434		)		—
(Income) attributable to operating affiliate investors	$	(109,399	)	$	(68,763	)		$	—
The portion of income attributable to operating affiliate investors that was due to the Company, as an investor in the affiliates, and third party investors for the year ended December 31, 2014 amounted to $21,756 and $87,643, respectively (2013: $11,437 and $57,326).

Noncontrolling_interest

Noncontrolling interest	12 Months Ended
	Dec. 31, 2014
Noncontrolling Interest [Abstract]
Noncontrolling interest	Noncontrolling interest
	On April 2, 2012, the Company joined with other investors in capitalizing PaCRe Ltd. ("PaCRe"), a Class 4 Bermuda reinsurer formed for the purpose of writing high excess property catastrophe reinsurance. The Company has an equity interest of 10% and the remaining 90% interest is held by third party investors. The Company has a majority voting equity interest in PaCRe and as a result, the financial statements of PaCRe are included in the Consolidated Financial Statements of the Company. The portion of PaCRe’s earnings attributable to third party investors is recorded in the Consolidated Statements of Comprehensive Income as net (income) loss attributable to noncontrolling interest. PaCRe's shareholder rights do not include redemption features within the control of the third party shareholders. The third party equity is recorded in the Company’s Consolidated Balance Sheets as noncontrolling interest.
	The portion of earnings from the one consolidated AlphaCat ILS fund attributable to third party investors is recorded in the Consolidated Statements of Comprehensive Income as net (income) loss attributable to noncontrolling interest. The AlphaCat ILS funds have rights that enable shareholders, subject to certain limitations, to redeem their shares. The third party equity is therefore recorded in the Company’s Consolidated Balance Sheets as redeemable noncontrolling interest. When and if a redemption notice is received, the fair value of the redemption is reclassified to a liability.
	The following table presents a reconciliation of the beginning and ending balances of redeemable noncontrolling interest and noncontrolling interest for the years ended December 31, 2014 and 2013:
		Year Ended December 31, 2014
		Redeemable noncontrolling interest			Noncontrolling interest			Total
	As at December 31, 2013	$	86,512		$	497,657		$	584,169
	Issuance of shares	68,200			—			68,200
	Income (loss) attributable to noncontrolling interest	3,598			(39,062		)	(35,464		)
	Adjustment to noncontrolling interest as a result of deconsolidation	(78,354		)	—			(78,354		)
	As at December 31, 2014	$	79,956		$	458,595		$	538,551
		Year Ended December 31, 2013
		Redeemable noncontrolling interest			Noncontrolling interest			Total
	As at December 31, 2012	$	—		$	434,280		$	434,280
	Issuance of shares	92,190			58,500			150,690
	Income attributable to noncontrolling interest	4,818			4,877			9,695
	Redemption of shares	(10,496		)	—			(10,496		)
	As at December 31, 2013	$	86,512		$	497,657		$	584,169

Derivative_instruments

Derivative instruments	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative instruments	Derivative instruments
	The Company enters into derivative instruments for risk management purposes, specifically to hedge unmatched foreign currency exposures and interest rate exposures. As at December 31, 2014, the Company held foreign currency forward contracts to mitigate the risk of fluctuations in the U.S. dollar against a number of foreign currencies. As at December 31, 2014, the Company held two interest rate swaps to fix the payment of interest on the Company's 2006 and 2007 Junior Subordinated Deferrable Debentures, as well as three interest rate swaps and one cross-currency interest rate swap to fix the payment of interest and mitigate the foreign exchange rate impact on Flagstone's 2006 and 2007 Junior Subordinated Deferrable Debentures.
	As at December 31, 2014, the Company held one foreign currency forward contract to mitigate the risk of fluctuations in the U.S. dollar against the Euro that was not designated as a hedging instrument.
	The following table summarizes information on the classification and amount of the fair value of derivatives not designated as hedging instruments on the Consolidated Balance Sheets at December 31, 2014 and December 31, 2013:
			As at December 31, 2014									As at December 31, 2013
	Derivatives not designated as hedging instruments:		Net Notional Exposure			Asset Derivative at Fair Value (a)			Liability Derivative at Fair Value (a)			Net Notional Exposure		Asset Derivative at Fair Value (a)		Liability Derivative at Fair Value (a)
	Foreign currency forward contracts		$	26,755		$	1,685		$	—		$	—	$	—	$	—
	(a)	Asset and liability derivatives are classified within other assets and accounts payable and accrued expenses respectively on the Consolidated Balance Sheets. The total impact on earnings during the year ended December 31, 2014, recognized in income within other insurance related income and other income, relating to the foreign currency forward contract that was not designated as a hedging instrument was $1,685.
	The following table summarizes information on the classification and amount of the fair value of derivatives designated as hedging instruments on the Consolidated Balance Sheets at December 31, 2014 and December 31, 2013:
			As at December 31, 2014									As at December 31, 2013
	Derivatives designated as hedging instruments:		Net Notional Exposure			Asset Derivative at Fair Value (a)			Liability Derivative at Fair Value (a)			Net Notional Exposure		Asset Derivative at Fair Value (a)		Liability Derivative at Fair Value (a)
	Foreign currency forward contracts		$	189,026		$	401		$	3,136		$	163,576	$	1,167	$	2,313
	Interest rate swap contracts		$	552,263		$	25		$	1,169		$	552,263	$	—	$	911
	(a)	Asset and liability derivatives are classified within other assets and accounts payable and accrued expenses respectively on the Consolidated Balance Sheets.
	(a)	Classification within the fair value hierarchy
	As described in Note 4: "Fair value measurements" under U.S. GAAP, a company must determine the appropriate level in the fair value hierarchy for each fair value measurement. The assumptions used within the valuation of the Company's derivative instruments are observable in the marketplace, can be derived from observable data or are supported by observable levels at which other similar transactions are executed in the marketplace. Accordingly, these derivatives were classified within Level 2 of the fair value hierarchy.
	(b)	Derivative instruments designated as a fair value hedge
	The Company designates its foreign currency derivative instruments as fair value hedges and formally and contemporaneously documents all relationships between the derivative instruments and hedged items and links the derivative instruments to specific assets and liabilities. The Company assesses the effectiveness of the hedges, both at inception and on an on-going basis and determines whether the hedges are highly effective in offsetting changes in fair value of the linked hedged items.
	The following table provides the total impact on earnings, recognized in income within foreign exchange (losses) gains, relating to the derivative instruments formally designated as fair value hedges along with the impact of the related hedged items for the years ended December 31, 2014, 2013 and 2012:
			Year Ended
	Foreign currency forward contracts		December 31, 2014			December 31, 2013			December 31, 2012
	Amount of (loss) gain recognized in income on derivative		$	(11,789	)	$	1,947		$	1,017
	Amount of gain (loss) on hedged item recognized in income attributable to risk being hedged		$	11,789		$	(1,947	)	$	(912	)
	Amount of gain recognized in income on derivative (ineffective portion)		$	—		$	—		$	105
	(c)	Derivative instruments designated as a cash flow hedge
	The Company designates its interest rate derivative instruments as cash flow hedges and formally and contemporaneously documents all relationships between the hedging instruments and hedged items and links the derivative instruments to specific assets and liabilities. The Company assesses the effectiveness of the hedges, both at inception and on an on-going basis and determines whether the hedges are highly effective in offsetting changes in fair value of the linked hedged items. The Company currently applies the long haul method when assessing the hedge's effectiveness.
	The following table provides the total impact on other comprehensive income (loss) and earnings relating to the derivative instruments formally designated as cash flow hedges along with the impact of the related hedged items for the years ended December 31, 2014, 2013 and 2012:
			Year Ended
	Interest rate swap contracts		December 31, 2014			December 31, 2013			December 31, 2012
	Amount of effective portion recognized in other comprehensive income		$	13,302		$	11,107		$	1,588
	Amount of effective portion subsequently reclassified to earnings		$	(13,074	)	$	(11,107	)	$	(1,588	)
	Amount of ineffective portion excluded from effectiveness testing		$	228		$	—		$	—
	The above balances relate to interest payments and have therefore been classified as finance expenses in the Consolidated Statements of Comprehensive Income.
	(d)	Balance sheet offsetting
	There was no balance sheet offsetting activity as at December 31, 2014 or December 31, 2013.
	The Company currently provides cash collateral as security for interest rate swap contracts. The Company does not provide cash collateral or financial instruments as security for foreign currency forward contracts. Our derivative instruments are generally traded under International Swaps and Derivatives Association master netting agreements, which establish terms that apply to all transactions. On a periodic basis, the amounts receivable from or payable to the counterparties are settled in cash.
	The Company has not elected to settle multiple transactions with an individual counterparty on a net basis.

Premiums_receivable

Premiums receivable	12 Months Ended
	Dec. 31, 2014
Premiums Receivable Disclosure [Abstract]
Premiums receivable	Premiums receivable
	Premiums receivable are composed of premiums in the course of collection, net of commissions and brokerage, and premiums accrued but unbilled, net of commissions and brokerage. It is common practice in the insurance and reinsurance industry for premiums to be paid on an installment basis, therefore significant amounts will be considered unbilled and will not become due until a future date, which is typically no later than expiration of the underlying coverage period. The following is a breakdown of the components of premiums receivable at December 31, 2014 and 2013:
		Premiums			Premiums			Total
		in course			accrued
		of collection			but unbilled
	Balance as at December 31, 2013	$	73,702		$	623,531		$	697,233
	Change during 2014	11,347			(933		)	10,414
	Balance as at December 31, 2014	$	85,049		$	622,598		$	707,647
	Balance as at December 31, 2012	$	214,891		$	587,268		$	802,159
	Change during 2013	(141,189		)	36,263			(104,926		)
	Balance as at December 31, 2013	$	73,702		$	623,531		$	697,233

Reserve_for_losses_and_loss_ex

Reserve for losses and loss expenses	12 Months Ended
	Dec. 31, 2014
Liability for Future Policy Benefits and Unpaid Claims and Claims Adjustment Expense [Abstract]
Reserve for losses and loss expenses	Reserve for losses and loss expenses
	Reserves for losses and loss expenses are based in part upon the estimation of case reserves from broker, insured and ceding company reported data. The Company also uses statistical and actuarial methods to estimate ultimate expected losses and loss expenses, from which incurred but not reported losses can be calculated. The period of time from the occurrence of a loss to the reporting of a loss to the Company and to the settlement of the Company's liability may be several months or years. During this period, additional facts and trends may be revealed. As these factors become apparent, reserves will be adjusted, sometimes requiring an increase or decrease in the overall reserves of the Company, and at other times requiring a reallocation of incurred but not reported reserves to specific case reserves. These estimates are reviewed and adjusted regularly, and such adjustments, if any, are reflected in earnings in the period in which they become known. While management believes that it has made a reasonable estimate of ultimate losses, there can be no assurances that ultimate losses and loss expenses will not exceed this estimate.
	The following table represents an analysis of paid and unpaid losses and loss expenses incurred and a reconciliation of the beginning and ending unpaid losses and loss expenses for the years ended December 31, 2014, 2013 and 2012:
		Years Ended
		31-Dec-14			December 31,			December 31,
					2013			2012
	Reserve for losses and loss expenses, beginning of year	$	3,030,399		$	3,517,573		$	2,631,143
	Losses and loss expenses recoverable	(370,154		)	(439,967		)	(372,485		)
	Net reserves for losses and loss expenses, beginning of year	2,660,245			3,077,606			2,258,658
	Net reserves acquired (disposed)	525,091			(36,519		)	639,641
	Increase (decrease) in net reserves for losses and loss expenses in respect of losses occurring in:
	Current year	1,024,256			999,380			1,174,415
	Prior years (a)	(252,207		)	(205,448		)	(174,969		)
	Total incurred losses and loss expenses (a)	772,049			793,932			999,446
	Less net losses and loss expenses paid in respect of losses occurring in:
	Current year	(245,084		)	(244,682		)	(182,146		)
	Prior years	(816,823		)	(916,796		)	(653,874		)
	Total net paid losses	(1,061,907		)	(1,161,478		)	(836,020		)
	Foreign exchange (gain) loss	(38,550		)	(13,296		)	15,881
	Net reserve for losses and loss expenses, end of year	2,856,928			2,660,245			3,077,606
	Losses and loss expenses recoverable	377,466			370,154			439,967
	Reserve for losses and loss expenses, end of year	$	3,234,394		$	3,030,399		$	3,517,573
	(a)	Upon closing the acquisition of Western World, an adjustment of $15,586 was made to increase net reserves to reflect fair value. This adjustment was amortized to income through a reduction in losses and loss expenses of $4,607 during the year ended December 31, 2014. The remaining fair value adjustment will be amortized in 2015.
	Incurred losses and loss expenses comprise:
		Years Ended
		December 31, 2014 (a)			December 31,			December 31,
					2013			2012
	Gross losses and loss expenses (a)	$	833,860		$	924,986		$	1,192,494
	Reinsurance recoverable	(61,811		)	(131,054		)	(193,048		)
	Net incurred losses and loss expenses (a)	$	772,049		$	793,932		$	999,446
	(a)	Upon closing the acquisition of Western World, an adjustment of $15,586 was made to increase net reserves to reflect fair value. This adjustment was amortized to income through a reduction in losses and loss expenses of $4,607 during the year ended December 31, 2014. The remaining fair value adjustment will be amortized in 2015.
	The December 31, 2014 and 2013 gross reserves balances comprise reserves for reported claims of $1,495,323 and $1,537,881, respectively, and reserves for claims incurred but not reported of $1,739,071 and $1,492,518, respectively. The net favorable development on prior years by segment and line of business is as follows:
		Year Ended December 31, 2014
		Property			Marine			Specialty			Liability			Total
	Validus Re	$	(76,064	)	$	(6,830	)	$	(4,706	)	$	—		$	(87,600	)
	AlphaCat	(12,201		)	—			—			—			(12,201		)
	Talbot	(53,779		)	(31,397		)	(55,990		)	—			(141,166		)
	Western World (a)	$	1,023		$	—		$	—		$	(12,263	)	$	(11,240	)
	Net favorable development (a)	$	(141,021	)	$	(38,227	)	$	(60,696	)	$	(12,263	)	$	(252,207	)
	(a)	Upon closing the acquisition, an adjustment of $15,586 was made to increase net reserves to reflect fair value. This adjustment was amortized to income through a reduction in losses and loss expenses of $4,607 during the year ended December 31, 2014. The remaining fair value adjustment will be amortized in 2015.
	The Validus Re property lines experienced favorable development primarily due to lower claims emergence on attritional losses and favorable loss development on Hurricane Sandy. The Validus Re marine and specialty lines experienced favorable development primarily due to lower claims emergence on attritional losses. The AlphaCat property lines experienced favorable development primarily due to the release of reserves on one aggregate excess of loss contract. Talbot experienced favorable development across all lines, primarily due to lower than expected claims development on attritional losses. Western World experienced unfavorable development on the property lines and favorable development on the liability lines, primarily due to claims development on attritional losses.
		Year Ended December 31, 2013
		Property			Marine			Specialty			Total (a)
	Validus Re	$	(81,610	)	$	26,705		$	(4,353	)	$	(59,258	)
	Talbot	(45,692		)	(46,092		)	(54,406		)	(146,190		)
	Net favorable development	$	(127,302	)	$	(19,387	)	$	(58,759	)	$	(205,448	)
	(a)	AlphaCat has not had any development on prior accident years.
	The Validus Re property and specialty lines experienced favorable development primarily due to lower claims emergence on attritional losses, although the property lines experienced unfavorable development due to increased estimate of ultimate losses on the New Zealand earthquakes. The Validus Re marine lines experienced unfavorable development primarily due to an increased estimate of ultimate losses on Costa Concordia. Talbot experienced favorable development across all lines, primarily due to lower than expected claims development on attritional losses.
		Year Ended December 31, 2012
		Property			Marine			Specialty			Total (a)
	Validus Re	$	(45,733	)	$	(11,298	)	$	(15,530	)	$	(72,561	)
	Talbot	(26,263		)	(40,060		)	(36,085		)	(102,408		)
	Net favorable development	$	(71,996	)	$	(51,358	)	$	(51,615	)	$	(174,969	)
	(a)	AlphaCat has not had any development on prior accident years.
	The Validus Re property and marine lines experienced favorable development primarily due to a reduction in the loss estimates on attritional losses, partially offset by increases in loss estimates on notable loss events. The Validus Re specialty lines experienced favorable development primarily due to lower than expected claims development on attritional losses. Talbot experienced favorable development across all lines, primarily due to lower than expected development on attritional losses.

Accounts_payable_and_accrued_e

Accounts payable and accrued expenses	12 Months Ended
	Dec. 31, 2014
Accounts Payable and Accrued Liabilities [Abstract]
Accounts payable and accrued expenses	Accounts payable and accrued expenses
	The following are the components of accounts payable and accrued expenses:
		Years Ended
		December 31,		December 31,
		2014		2013
	Accrued interest on debt	$	12,224	$	10,686
	Subscriptions received in advance on AlphaCat ILS funds	15,400		35,000
	Accrued income attributable to operating affiliates	109,399		68,763
	Trade and compensation payables	181,222		163,738
	Total accounts payable and accrued expenses	$	318,245	$	278,187

Reinsurance

Reinsurance	12 Months Ended
	Dec. 31, 2014
Reinsurance Disclosures [Abstract]
Reinsurance	Reinsurance
	The Company enters into reinsurance and retrocession agreements in order to mitigate its accumulation of loss, reduce its liability on individual risks, enable it to underwrite policies with higher limits and increase its aggregate capacity. The cession of insurance and reinsurance does not legally discharge the Company from its primary liability for the full amount of the policies, and the Company is required to pay the loss and bear collection risk if the reinsurer fails to meet its obligations under the reinsurance or retrocession agreement. Amounts recoverable from reinsurers are estimated in a manner consistent with the underlying liabilities.
	(a)	Effects of reinsurance on premiums written and earned
	The effects of reinsurance on premiums written and earned for the years ended December 31, 2014, 2013 and 2012 are as follows:
		Year Ended December 31, 2014
		Validus Re								AlphaCat							Talbot						Western World						Eliminations						Total
		Written				Earned				Written				Earned			Written			Earned			Written			Earned			Written			Earned			Written			Earned
	Direct	$	—			$	—			$	—			$	—		$	617,793		$	576,136		$	65,235		$	80,838		$	—		$	—		$	683,028		$	656,974
	Assumed	1,136,910				1,127,894				135,181				135,884			483,977			508,634			—			—			(75,810		)	(83,168		)	1,680,258			1,689,244
	Ceded	(182,056		)		(210,610		)		(4,348		)		(3,534		)	(192,211		)	(204,996		)	(6,428		)	(7,842		)	75,810			83,168			(309,233		)	(343,814		)
	Total	$	954,854			$	917,284			$	130,833			$	132,350		$	909,559		$	879,774		$	58,807		$	72,996		$	—		$	—		$	2,054,053		$	2,002,404
		Year Ended December 31, 2013
		Validus Re								AlphaCat							Talbot						Eliminations						Total
		Written				Earned				Written				Earned			Written			Earned			Written			Earned			Written			Earned
	Direct	$	—			$	—			$	—			$	—		$	544,722		$	519,045		$	—		$	—		$	544,722		$	519,045
	Assumed	1,242,522				1,360,735				147,009				137,939			547,168			532,069			(80,315		)	(78,833		)	1,856,384			1,951,910
	Ceded	(226,264		)		(226,798		)		(525		)		(525		)	(226,111		)	(220,420		)	80,315			78,833			(372,585		)	(368,910		)
	Total	$	1,016,258			$	1,133,937			$	146,484			$	137,414		$	865,779		$	830,694		$	—		$	—		$	2,028,521		$	2,102,045
		Year Ended December 31, 2012
		Validus Re								AlphaCat							Talbot						Eliminations						Total
		Written				Earned				Written				Earned			Written			Earned			Written			Earned			Written			Earned
	Direct	$	1,551			$	364			$	—			$	—		$	548,940		$	535,508		$	—		$	—		$	550,491		$	535,872
	Assumed	1,130,408				1,174,681				21,603				17,666			529,696			529,544			(65,758		)	(73,934		)	1,615,949			1,647,957
	Ceded	(144,578		)		(151,774		)		—				—			(228,686		)	(232,773		)	65,758			73,934			(307,506		)	(310,613		)
	Total	$	987,381			$	1,023,271			$	21,603			$	17,666		$	849,950		$	832,279		$	—		$	—		$	1,858,934		$	1,873,216
	(b)	Credit risk
	The Company evaluates the financial condition of its reinsurers and monitors concentration of credit risk arising from its exposure to individual reinsurers. The reinsurance program is generally placed with reinsurers whose rating, at the time of placement, was A- or better as rated by Standard & Poor's or the equivalent with other rating agencies. Exposure to a single reinsurer is also controlled with restrictions dependent on rating. At December 31, 2014, 98.0% (December 31, 2013: 96.7%) of reinsurance recoverables (which includes loss reserves recoverable and recoverables on paid losses and $231,129 of total IBNR recoverable (December 31, 2013: $196,840)) were fully collateralized or from reinsurers rated A- or better.
	Reinsurance recoverables by reinsurer are as follows:
		December 31, 2014							December 31, 2013
		Reinsurance Recoverable				% of Total			Reinsurance Recoverable				% of Total
	Top 10 reinsurers	$	312,205			75.1	%		$	340,938			75.7	%
	Other reinsurers’ balances > $1 million	94,247				22.7	%		100,784				22.4	%
	Other reinsurers’ balances < $1 million	9,092				2.2	%		8,512				1.9	%
	Total	$	415,544			100	%		$	450,234			100	%
			December 31, 2014
	Top 10 Reinsurers		Rating		Reinsurance Recoverable				% of Total
	Swiss Re		AA-		$	70,848			17	%
	Lloyd's Syndicates		A+		62,318				15	%
	Everest Re		A+		51,425				12.4	%
	Hannover Re		AA-		40,927				9.8	%
	Fully Collateralized		NR		23,315				5.6	%
	Munich Re		AA-		19,384				4.7	%
	Transatlantic Re		A+		12,418				3	%
	XL Re		A+		11,114				2.7	%
	Berkshire Hathaway Homestate		AA+		10,372				2.5	%
	Merrimack Mutual Fire Insurance		A+		10,084				2.4	%
	Total				$	312,205			75.1	%
			December 31, 2013
	Top 10 Reinsurers		Rating		Reinsurance Recoverable				% of Total
	Lloyd's Syndicates		A+		$	73,398			16.3	%
	National Indemnity		AA+		51,037				11.3	%
	Everest Re		A+		48,113				10.7	%
	Hannover Re		AA-		41,483				9.2	%
	Fully Collateralized		NR		36,683				8.1	%
	Third Point Re		A-		30,428				6.8	%
	Swiss Re		AA-		20,022				4.5	%
	Transatlantic Re		A+		14,114				3.1	%
	XL Re		A+		13,300				3	%
	Munich Re		AA-		12,360				2.7	%
	Total				$	340,938			75.7	%
	NR: Not rated
	At December 31, 2014 and December 31, 2013, the provision for uncollectible reinsurance relating to reinsurance recoverables was $4,755 and $5,794, respectively. To estimate the provision for uncollectible reinsurance, the reinsurance recoverable is first allocated to applicable reinsurers. This determination is based on a process rather than an estimate, although an element of judgment is applied, especially in relation to ceded IBNR. The Company then uses default factors to determine the portion of a reinsurer’s balance deemed to be uncollectible. Default factors require considerable judgment and are determined in part using the current rating, or rating equivalent, of each reinsurer as well as other key considerations and assumptions.

Share_capital

Share capital	12 Months Ended
	Dec. 31, 2014
Stockholders' Equity Note [Abstract]
Share capital	Share capital
	(a)	Authorized and issued
	The Company’s authorized share capital is 571,428,571 common shares with a par value of $0.175 per share. The holders of common shares are entitled to receive dividends. Holders of common shares are allocated one vote per share, provided that, if the controlled shares of any shareholder or group of related shareholders constitute more than 9.09 percent of the outstanding common shares of the Company, their voting power will be reduced to 9.09 percent.
	The Company may from time to time repurchase its securities, including common shares, Junior Subordinated Deferrable Debentures and Senior Notes. On February 5, 2014, the Board of Directors of the Company approved an increase in the Company's common share repurchase authorization to $500,000. This amount was in addition to the $1,774,436 of common shares repurchased by the Company through February 5, 2014 under its previously authorized share repurchase programs.
	The Company has repurchased approximately 70,045,504 common shares for an aggregate purchase price of $2,231,301 from the inception of its share repurchase program to December 31, 2014. The Company had $43,135 remaining under its authorized share repurchase program as of December 31, 2014.
	The Company expects the purchases under its share repurchase program to be made from time to time in the open market or in privately negotiated transactions. The timing, form and amount of the share repurchases under the program will depend on a variety of factors, including market conditions, the Company’s capital position relative to internal and rating agency targets, legal requirements and other factors. The repurchase program may be modified, extended or terminated by the Board of Directors at any time.
	On November 30, 2012, the Company acquired all of the outstanding shares of Flagstone from a group of institutional and other investors. Pursuant to a merger agreement, the Company acquired all of Flagstone's outstanding common shares in exchange for the Company's common shares and cash. The Company issued 14,202,664 common shares, net of 87,725 shares withheld for income taxes, valued at $34.87 per share as partial consideration for the acquisition. In addition, 1,638,875 common shares recorded in treasury are owned by Validus UPS, Ltd., a wholly-owned subsidiary of the Company. As part of the Flagstone Acquisition, warrants to acquire Flagstone shares were converted into 121,942 warrants to acquire the Company's common shares. In accordance with the merger agreement, these warrants had a $62.02 strike price and expired without being exercised.
	The following table is a summary of the common shares issued and outstanding:
		Common Shares
	Common shares issued, December 31, 2013	154,488,497
	Restricted share awards vested, net of shares withheld	615,659
	Restricted share units vested, net of shares withheld	10,265
	Options exercised	412,656
	Direct issuance of common stock	1,380
	Performance shares vested, net of shares withheld	25,767
	Common shares issued, December 31, 2014	155,554,224
	Treasury shares, December 31, 2014	(71,684,379	)
	Common shares outstanding, December 31, 2014	83,869,845
		Common Shares
	Common shares issued, December 31, 2012	152,698,191
	Restricted share awards vested, net of shares withheld	796,838
	Restricted share units vested, net of shares withheld	14,381
	Options exercised	351,509
	Warrants exercised	591,480
	Direct issuance of common stock	1,266
	Performance shares vested, net of shares withheld	31,897
	Deferred share units vested, net of shares withheld	2,935
	Common shares issued, December 31, 2013	154,488,497
	Treasury shares, December 31, 2013	(58,444,185	)
	Common shares outstanding, December 31, 2013	96,044,312
		Common Shares
	Common shares issued, December 31, 2011	134,503,065
	Restricted share awards vested, net of shares withheld	1,572,634
	Restricted share units vested, net of shares withheld	15,173
	Options exercised	439,065
	Warrants exercised	326,715
	Direct issuance of common stock	15,841,539
	Common shares issued, December 31, 2012	152,698,191
	Treasury shares, December 31, 2012	(44,776,932	)
	Common shares outstanding, December 31, 2012	107,921,259
	(b)	Warrants
	The Company had total outstanding warrants as at December 31, 2014 of 5,174,114 (2013: 5,296,056), with each warrant providing the holder with the option to purchase a common share. No further warrants are anticipated to be issued.
	The warrants may be settled using either the physical settlement or net-share settlement methods. The warrants have been classified as equity instruments, in accordance with U.S. GAAP guidance for “Derivatives and Hedging, Contracts in Entity’s own Equity.” The warrants were measured at fair value and recorded in additional paid-in capital.
	The fair value of each warrant issued was estimated on the date of grant using the Black-Scholes option-pricing model. The volatility assumption used, of approximately 30.0%, was derived from the historical volatility of the share price of a range of publicly-traded Bermuda reinsurance companies of a similar business nature to the Company. No allowance was made for any potential illiquidity associated with the private trading of the Company’s shares. The other assumptions in the warrant-pricing model were as follows:
		July 24,			February 3,			December 15,
		2007			2006			2005
		Issuance			Issuance			Issuance
	Warrants issued	256,409			8,593			8,446,727
	Average strike price	$	20		$	17.5		$	17.5
	Volatility	30		%	30		%	30		%
	Risk-free rate	4.5		%	4.5		%	4.5		%
	Expected dividend yield	0		%	0		%	0		%
	Expected term (years)	8			10			10
	Calculated fair value per warrant	$	11.28		$	8.89		$	8.89
	During the year ended December 31, 2014, no warrants were exercised, while 121,942 warrants related to the Flagstone Acquisition expired without being exercised. During the year ended December 31, 2013, 1,114,416 warrants were exercised which resulted in the issuance of 591,480 common shares. Holders of the outstanding warrants are entitled to exercise the warrant in whole or in part at any time until the expiration date.
	(c)	Deferred share units
	Under the terms of the Company’s Director Stock Compensation Plan, non-management directors may elect to receive their director retainer fees in deferred share units rather than cash. The number of share units distributed in case of election under the plan is equal to the amount of the annual retainer fee otherwise payable to the director on such payment date divided by 100% of the fair market value of a share on such payment date. Additional deferred share units are issued in lieu of dividends that accrue on these deferred share units. There were no outstanding deferred share units at December 31, 2014 (2013: nil).
	As of February 16, 2013, John Hendrickson became an employee director. As a result, his 5,039 deferred share units vested and 2,935 common shares were issued to him, net of shares withheld for taxes.
	(d)	Dividends
	The Company announced four quarterly cash dividends of $0.30 per common share and $0.30 per common share equivalent for which each outstanding warrant is exercisable, during the year ended December 31, 2014 (2013: $0.30). These dividends were paid on March 31, 2014, June 30, 2014, September 30, 2014 and December 31, 2014 to holders of record on March 14, 2014, June 13, 2014, September 15, 2014 and December 15, 2014, respectively.

Retirement_and_pension_plans

Retirement and pension plans	12 Months Ended
	Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Retirement and pension plans	Retirement and pension plans
	(a)	Defined benefit plans
	Senior executives and retired selected key employees of Western World participate in non-qualified, unfunded, defined benefit plans. Benefits for these plans are based on final average earnings, social security benefits earned at retirement date and years of service.
	The assumptions used to determine net periodic pension expense for the year ended December 31, 2014 are as follows:
		Year Ended December 31, 2014
	Discount rate	3	%
	Increase in compensation levels rate	5	%
	The assumptions used to determine benefit obligations as at December 31, 2014 are as follows:
		As at December 31, 2014
	Discount rate	2.75	%
	Increase in compensation levels rate	5	%
	The following tables present a reconciliation of the beginning and ending funded status and the net amounts recognized for the defined benefit plans for the year ended December 31, 2014:
		Year Ended December 31, 2014 (a)
	Change in benefit obligation:
	Projected benefit obligation as at October 2, 2014	$	20,885
	Service cost	295
	Interest cost	145
	Actuarial losses	1
	Benefit payments	(24		)
	Settlements	(4,809		)
	Projected benefit obligation as at December 31, 2014	$	16,493
	Change in plan assets:
	Fair value of plan assets as at October 2, 2014	$	—
	Employer contributions	6,495
	Benefit payments	(24		)
	Settlements	(6,471		)
	Fair value of plan assets as at December 31, 2014	—
	Funded status as at December 31, 2014	$	(16,493	)
	Current liabilities	$	(559	)
	Noncurrent liabilities	(15,934		)
	Net amount recognized	$	(16,493	)
	Amounts recognized in accumulated other comprehensive (loss) income consist of:
	Net loss	$	4,505
	Prior service credit	(4		)
	Net amount recognized	$	4,501
		As at December 31, 2014
	Projected benefit obligation	$	16,493
	Accumulated benefit obligation	$	11,971
	Fair value of plan assets	$	—
	(a)	The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.
	The components of net periodic pension expense for the year ended December 31, 2014 are as follows:
		Year Ended December 31, 2014
	Service cost	$	295
	Interest cost	145
	Amortization of prior service cost	(1		)
	Amortization of net loss	79
	Net periodic benefit cost	518
	Settlement loss	1,322
	Net periodic pension expense	$	1,840
	Other changes in plan assets and benefit obligations recognized in other comprehensive (loss) income are as follows for the year ended December 31, 2014:
		Year Ended December 31, 2014
	Net loss	$	1,961
	Amortization of loss	(317		)
	Amortization of prior service cost	2
	Settlement loss	(1,322		)
	Total recognized in other comprehensive (loss) income	$	324
	Total recognized in net pension expense and other comprehensive (loss) income (before tax effects)	$	2,164
	The estimated amount of net loss and prior service cost expected to be amortized from accumulated other comprehensive (loss) income into net periodic pension expense over the next fiscal year is $2.
	The employer benefit payments/settlements for the year ended December 31, 2014 were $4,834. As at December 31, 2014, the projected benefits are as follows:
	2015		$	559
	2016		93
	2017		6,921
	2018		85
	2019		2,160
2020-2024		5,228
Total benefit payments required		$	15,046
(b)	Other pension plans
The Company provides pension benefits to eligible employees through various plans which are managed externally and sponsored by the Company. The Company’s contributions are expensed as incurred. The Company’s expenses for its defined contribution retirement plans for the years ended December 31, 2014, 2013 and 2012 were $10,606, $7,621 and $9,233, respectively.

Stock_plans

Stock plans	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock plans	Stock plans
	(a)	Long Term Incentive Plan and Short Term Incentive Plan
	The Company’s Amended and Restated 2005 Long Term Incentive Plan (“LTIP”) provides for grants to employees of options, stock appreciation rights (“SARs”), restricted shares, restricted share units, performance shares, dividend equivalents or other share-based awards. In addition, the Company may issue restricted share awards or restricted share units in connection with awards issued under its annual Short Term Incentive Program (“STIP”). The total number of shares reserved for issuance under the LTIP and STIP are 13,126,896 shares of which 903,292 shares are remaining. The LTIP and STIP are administered by the Compensation Committee of the Board of Directors. No SARs have been granted to date. Grant prices are established at the fair market value of the Company’s common shares at the date of grant.
	i.	Options
	Options may be exercised for voting common shares upon vesting. Options have a life of 10 years and vest either pro rata or at the end of the required service period from the date of grant. Fair value of the option awards at the date of grant is determined using the Black-Scholes option-pricing model.
	Expected volatility is based on stock price volatility of comparable publicly-traded companies. The Company used the simplified method consistent with U.S. GAAP authoritative guidance on stock compensation expenses to estimate expected lives for options granted during the period as historical exercise data was not available and the options met the requirement as set out in the guidance.
	The Company has not granted any stock option awards since September 4, 2009.
	Share compensation expenses in respect of options of $nil were recorded for the year ended December 31, 2014 (2013: $nil, 2012: $142). The expenses represent the proportionate accrual of the fair value of each grant based on the remaining vesting period.
	A modification event was triggered as a result of a $2.00 per share special dividend declared and paid in 2013 (the "Special Dividend"). In accordance with the terms of the LTIP under which the options were issued, an adjustment was required to protect the holders of such stock options from changes in the value of the stock options following the declaration of the 2013 Special Dividend. The modification of the options included a decrease in the exercise price of each stock option and an increase in the number of shares underlying each stock option. The fair value of the options before and after the modification was unchanged.
	Activity with respect to options for the year ended December 31, 2014 was as follows:
		Options		Weighted Average Grant Date Fair Value				Weighted Average Grant Date Exercise Price			Total		Company Proceeds Received
											Intrinsic Value (a)
	Options outstanding and exercisable, December 31, 2013	1,572,713		$	6.66			$	18.88
	Options exercised	(412,656	)	5.36				22.07			$	7,459	$	9,107
	Options outstanding and exercisable, December 31, 2014	1,160,057		$	7.12			$	17.74
	Activity with respect to options for the year ended December 31, 2013 was as follows:
		Options		Weighted Average Grant Date Fair Value				Weighted Average Grant Date Exercise Price			Total		Company Proceeds Received
											Intrinsic Value (a)
	Options outstanding and exercisable, December 31, 2012	1,823,947		$	6.52			$	20.69
	Options regranted (modified)	1,833,414		6.76				19.02
	Options exercised	(351,509	)	5.94				22.91			$	4,963	$	8,052
	Options cancelled (modified)	(1,733,139	)	6.76				20.12
	Options outstanding and exercisable, December 31, 2013	1,572,713		$	6.66			$	18.88
	Activity with respect to options for the year ended December 31, 2012 was as follows:
		Options		Weighted Average Grant Date Fair Value				Weighted Average Grant Date Exercise Price			Total		Company Proceeds Received
											Intrinsic Value (a)
	Options outstanding and exercisable, December 31, 2011	2,263,012		$	6.69			$	20.12
	Options exercised	(439,065	)	7.44				17.73			$	6,574	$	7,785
	Options outstanding and exercisable, December 31, 2012	1,823,947		$	6.52			$	20.69
	(a)	The total intrinsic value in the tables above represent the amount by which the market price of the Company's common stock is greater than the option strike price multiplied by the number of options exercised during the year.
	There were no unamortized share compensation expenses in respect of options since December 31, 2012. The aggregate intrinsic value of the options outstanding and exercisable at December 31, 2014 was $27,573.
	ii.	Restricted share awards
	Restricted shares granted under the LTIP and STIP vest either pro rata or at the end of the required service period and contain certain restrictions during the vesting period, relating to, among other things, forfeiture in the event of termination of employment and transferability. Share compensation expenses of $31,335 were recorded for the year ended December 31, 2014 (2013: $27,750; 2012: $25,145). The expenses represent the proportionate accrual of the fair value of each grant based on the remaining vesting period.
	Activity with respect to unvested restricted share awards for the year ended December 31, 2014 was as follows:
		Restricted Share Awards		Weighted Average Grant Date Fair Value
	Restricted share awards outstanding, December 31, 2013	2,684,745		$	33.74
	Restricted share awards granted	1,051,348		37.81
	Restricted share awards vested	(797,446	)	31.44
	Restricted share awards forfeited	(79,936	)	36.09
	Restricted share awards outstanding, December 31, 2014	2,858,711		$	35.81
	Activity with respect to unvested restricted share awards for the year ended December 31, 2013 was as follows:
		Restricted Share Awards		Weighted Average Grant Date Fair Value
	Restricted share awards outstanding, December 31, 2012	2,170,547		$	29.24
	Restricted share awards granted	1,594,672		36.07
	Restricted share awards vested	(969,562	)	28.12
	Restricted share awards forfeited	(110,912	)	28.34
	Restricted share awards outstanding, December 31, 2013	2,684,745		$	33.74
	Activity with respect to unvested restricted share awards for the year ended December 31, 2012 was as follows:
		Restricted Share Awards		Weighted Average Grant Date Fair Value
	Restricted share awards outstanding, December 31, 2011	3,003,547		$	25.77
	Restricted share awards granted	921,506		31.47
	Restricted share awards vested	(1,719,855	)	24.4
	Restricted share awards forfeited	(34,651	)	27.85
	Restricted share awards outstanding, December 31, 2012	2,170,547		$	29.24
	At December 31, 2014, there were $74,670 (2013: $69,219; 2012: $43,952) of total unrecognized share compensation expenses in respect of restricted share awards that are expected to be recognized over a weighted-average period of 2.7 years (2013: 3.2 years; 2012: 2.6 years).
	iii.	Restricted share units
	Restricted share units under the LTIP and STIP vest either ratably or at the end of the required service period and contain certain restrictions during the vesting period, relating to, among other things, forfeiture in the event of termination of employment and transferability. Share compensation expenses of $876 were recorded for the year ended December 31, 2014 (2013: $585; 2012: $499). The expenses represent the proportionate accrual of the fair value of each grant based on the remaining vesting period.
	Activity with respect to unvested restricted share units for the year ended December 31, 2014 was as follows:
		Restricted Share Units		Weighted Average Grant Date Fair Value
	Restricted share units outstanding, December 31, 2013	66,518		$	33.74
	Restricted share units granted	53,025		38.1
	Restricted share units vested	(18,325	)	30.71
	Restricted share units issued in lieu of cash dividends	2,266		35
	Restricted share units outstanding, December 31, 2014	103,484		$	36.54
Activity with respect to unvested restricted share units for the year ended December 31, 2013 was as follows:
	Restricted Share Units		Weighted Average Grant Date Fair Value
Restricted share units outstanding, December 31, 2012	47,238		$	29.61
Restricted share units granted	36,635		36.11
Restricted share units vested	(21,814	)	28.17
Restricted share units issued in lieu of cash dividends	4,459		30.7
Restricted share units outstanding, December 31, 2013	66,518		$	33.74
Activity with respect to unvested restricted share units for the year ended December 31, 2012 was as follows:
	Restricted Share Units		Weighted Average Grant Date Fair Value
Restricted share units outstanding, December 31, 2011	53,312		$	27.6
Restricted share units granted	16,633		31.77
Restricted share units vested	(22,818	)	26.49
Restricted share units issued in lieu of cash dividends	1,504		28.66
Restricted share units forfeited	(1,393	)	28.57
Restricted share units outstanding, December 31, 2012	47,238		$	29.61
At December 31, 2014, there were $2,774 (2013: $1,678; 2012: $978) of total unrecognized share compensation expenses in respect of restricted share units that are expected to be recognized over a weighted-average period of 3.1 years (2013: 3.4 years; 2012: 2.6 years).
iv.	Performance share awards
The performance share awards contain a performance based component. The performance component relates to the compounded growth in the Dividend Adjusted Book Value per Diluted Share (“DBVPS”) over a three year period. For performance share awards granted during the period, the grant date is based on the DBVPS at the end of the most recent financial reporting year. The Dividend Adjusted Performance Period End DBVPS will be the DBVPS three years after the grant date DBVPS. The fair value estimate earns over the requisite attribution period and the estimate will be reassessed at the end of each performance period which will reflect any adjustments in the consolidated statements of comprehensive income in the period in which they are determined.
Share compensation expenses of $862 were recorded for the year ended December 31, 2014 (2013: ($705); 2012: $923). The share compensation expenses represent the proportionate accrual of the fair value of each grant based on the remaining vesting period. The negative expense is due to a reversal of expenses on unvested performance share awards based on a review of current and projected performance criteria.
Activity with respect to unvested performance share awards for the year ended December 31, 2014 was as follows:
	Performance Share Awards		Weighted Average Grant Date Fair Value
Performance share awards outstanding, December 31, 2013	101,820		$	33.56
Performance share awards granted	52,639		37.33
Performance share awards vested	(32,746	)	32.62
Performance share awards conversion adjustment	(15,344	)	31.38
Performance share awards outstanding, December 31, 2014	106,369		$	36.03
Activity with respect to unvested performance share awards for the year ended December 31, 2013 was as follows:
	Performance Share Awards		Weighted Average Grant Date Fair Value
Performance share awards outstanding, December 31, 2012	220,845		$	31.81
Performance share awards granted	38,386		36.11
Performance share awards vested	(39,094	)	28.7
Performance share awards forfeited	(18,701	)	31.05
Performance share awards conversion adjustment	(99,616	)	33.05
Performance share awards outstanding, December 31, 2013	101,820		$	33.56
Activity with respect to unvested performance share awards for the year ended December 31, 2012 was as follows:
	Performance Share Awards		Weighted Average Grant Date Fair Value
Performance share awards outstanding, December 31, 2011	279,019		$	30.77
Performance share awards granted	41,128		31.38
Performance share awards forfeited	(99,302	)	28.7
Performance share awards outstanding, December 31, 2012	220,845		$	31.81
At December 31, 2014, there were $2,232 (2013: $1,642; 2012: $3,328) of total unrecognized share compensation expenses in respect of performance share awards that are expected to be recognized over a weighted-average period of 2.1 years (2013: 2.0 years; 2012: 1.7 years).
(b)	Total share compensation expenses
The breakdown of share compensation expenses by award type was as follows:
	Years Ended
	December 31, 2014			December 31, 2013				December 31,
								2012
Options	$	—		$	—			$	142
Restricted share awards	31,335			27,750				25,145
Restricted share units	876			585				499
Performance share awards	862			(705		)		923
Total	$	33,073		$	27,630			$	26,709
In addition, the Company recorded $1,610 of associated tax benefits for the year ended December 31, 2014 (2013: $1,423; 2012: $1,380). The Company also recognized $3,513 of net windfall taxes at December 31, 2014 for share vestings and option exercises from inception to date.

Debt_and_financing_arrangement

Debt and financing arrangements	12 Months Ended
	Dec. 31, 2014
Debt Disclosure [Abstract]
Debt and financing arrangements	Debt and financing arrangements
	(a)	Financing structure
	The financing structure at December 31, 2014 was:
		Commitment			Issued and outstanding (a)				Drawn
	2006 Junior Subordinated Deferrable Debentures	$	150,000		$	150,000			$	150,000
	2007 Junior Subordinated Deferrable Debentures	200,000			139,800				139,800
	Flagstone 2006 Junior Subordinated Deferrable Debentures	135,727			135,727				135,727
	Flagstone 2007 Junior Subordinated Deferrable Debentures	113,750			113,750				113,750
	Total debentures payable	599,477			539,277				539,277
	2010 Senior Notes due 2040	250,000			250,000				247,306
	Total debentures and senior notes payable	849,477			789,277				786,583
	$400,000 syndicated unsecured letter of credit facility	400,000			—				—
	$525,000 syndicated secured letter of credit facility	525,000			276,455				—
	$200,000 secured bi-lateral letter of credit facility	200,000			15,649				—
	Talbot FAL facility	25,000			25,000				—
	PaCRe senior secured letter of credit facility	10,000			294				—
	AlphaCat Re secured letter of credit facility	30,000			30,000				—
	IPC bi-lateral facility	40,000			15,897				—
	$375,000 Flagstone bi-lateral facility	375,000			198,389				—
	Total credit and other facilities	1,605,000			561,684				—
	Total debt and financing arrangements	$	2,454,477		$	1,350,961			$	786,583
	The financing structure at December 31, 2013 was:
		Commitment			Issued and outstanding (a)				Drawn
	2006 Junior Subordinated Deferrable Debentures	$	150,000		$	150,000			$	150,000
	2007 Junior Subordinated Deferrable Debentures	200,000			139,800				139,800
	Flagstone 2006 Junior Subordinated Deferrable Debentures	137,866			137,866				137,866
	Flagstone 2007 Junior Subordinated Deferrable Debentures	113,750			113,750				113,750
	Total debentures payable	601,616			541,416				541,416
	2010 Senior Notes due 2040	250,000			250,000				247,198
	Total debentures and senior notes payable	851,616			791,416				788,614
	$400,000 syndicated unsecured letter of credit facility	400,000			—				—
	$525,000 syndicated secured letter of credit facility	525,000			358,567				—
	$200,000 secured bi-lateral letter of credit facility	200,000			16,726				—
	Talbot FAL facility	25,000			25,000				—
	PaCRe senior secured letter of credit facility	10,000			294				—
	AlphaCat Re secured letter of credit facility	24,800			24,800				—
	IPC bi-lateral facility	40,000			20,177				—
	$375,000 Flagstone bi-lateral facility	375,000			305,686				—
	Total credit and other facilities	1,599,800			751,250				—
	Total debt and financing arrangements	$	2,451,416		$	1,542,666			$	788,614
	(a)	Indicates utilization of commitment amount, not necessarily drawn borrowings.
	(b)	Senior notes and junior subordinated deferrable debentures
	The following table summarizes the key terms of the Company's senior notes and junior subordinated deferrable debentures as at the issuance date for each placement.
	Description	Issuance date	Commitment		Maturity date	Fixed/Spread			Interest payments due
	2006 Junior Subordinated Deferrable Debentures	June 15, 2006	$	150,000	June 15, 2036	9.069	%	(a)	Quarterly
	Flagstone 2006 Junior Subordinated Deferrable Debentures	August 23, 2006	$	135,727	September 15, 2036	3.54	%	(b)	Quarterly
	2007 Junior Subordinated Deferrable Debentures	June 21, 2007	$	200,000	June 15, 2037	8.48	%	(a)	Quarterly
	Flagstone 2007 Junior Subordinated Deferrable Debentures	June 8, 2007	$	88,750	July 30, 2037	3	%	(b)	Quarterly
	Flagstone 2007 Junior Subordinated Deferrable Debentures	September 20, 2007	$	25,000	September 15, 2037	3.1	%	(b)	Quarterly
	2010 Senior Notes due 2040	January 26, 2010	$	250,000	January 26, 2040	8.875	%	(a)	Semi-annually in arrears
	(a)	Fixed interest rate.
	(b)	Variable interest rate is the three-month LIBOR, reset quarterly, plus spread as noted in the table.
	The following table summarizes the key terms of the Company's senior notes and junior subordinated deferrable debentures as at December 31, 2014:
	Description	Issuance date	Commitment		Maturity date	Fixed/Spread			Interest payments due
	2006 Junior Subordinated Deferrable Debentures	June 15, 2006	$	150,000	June 15, 2036	5.831	%	(b)	Quarterly
	Flagstone 2006 Junior Subordinated Deferrable Debentures	August 23, 2006	$	135,727	September 15, 2036	6.463	%	(b)	Quarterly
	2007 Junior Subordinated Deferrable Debentures	June 21, 2007	$	200,000	June 15, 2037	5.18	%	(b)	Quarterly
	Flagstone 2007 Junior Subordinated Deferrable Debentures	8-Jun-07	$	88,750	July 30, 2037	5.9	%	(b)	Quarterly
	Flagstone 2007 Junior Subordinated Deferrable Debentures	20-Sep-07	$	25,000	September 15, 2037	5.983	%	(b)	Quarterly
	2010 Senior Notes due 2040	26-Jan-10	$	250,000	January 26, 2040	8.875	%	(a)	Semi-annually in arrears
	(a)	Fixed interest rate.
	(b)	Interest rate has been fixed as a result of interest rate swap contracts entered into by the Company.
	Senior Notes
	The Senior Notes due 2040 (the “2010 Senior Notes”) were part of a registered public offering. The 2010 Senior Notes mature on January 26, 2040.  The Company may redeem the notes, in whole at any time, or in part from time to time, at the Company's option on not less than 30 nor more than 60 days’ notice, at a make-whole redemption price as described in “Description of the Notes - Optional Redemption” in the 2010 Senior Notes prospectus supplement.  In addition, the Company may redeem the notes, in whole, but not in part, at any time upon the occurrence of certain tax events as described in “Description of the Notes - Redemption for Tax Purposes” in the prospectus supplement.
Debt issuance costs were deferred as an asset and are amortized over the life of the 2010 Senior Notes. There were no redemptions made during the years ended December 31, 2014 and 2013.
The 2010 Senior Notes are unsecured and unsubordinated obligations of the Company and rank equally in right of payment with all of the Company’s existing and future unsecured and unsubordinated indebtedness. The 2010 Senior Notes will be effectively junior to all of the Company’s future secured debt, to the extent of the value of the collateral securing such debt, and will rank senior to all our existing and future subordinated debt. The 2010 Senior Notes are structurally subordinated to all obligations of the Company’s subsidiaries.
Future payments of principal of $250,000 on the 2010 Senior Notes are all expected to be after 2019.
Junior subordinated deferrable debentures
The Company participated in private placements of junior subordinated deferrable interest debentures due 2036 and 2037 (respectively, the “2006 Junior Subordinated Deferrable Debentures” and “2007 Junior Subordinated Deferrable Debentures”).
Debt issuance costs for the 2006 and 2007 Junior Subordinated Deferrable Debentures were deferred as an asset and were amortized to income over the five year optional redemption periods. They are redeemable at the Company's option at par. There were no redemptions made during the years ended December 31, 2014 and 2013.
As part of the acquisition of Flagstone, the Company assumed junior subordinated deferrable debentures due 2036 and 2037 (respectively, the “Flagstone 2006 Junior Subordinated Deferrable Debentures” and “Flagstone 2007 Junior Subordinated Deferrable Debentures”). These debentures are redeemable quarterly at par. There were no redemptions made during the years ended December 31, 2014 and 2013.
Future payments of principal of $539,277 on the debentures discussed above are all expected to be after 2019.
(c)	Credit facilities
i.	$400,000 syndicated unsecured letter of credit facility and $525,000 syndicated secured letter of credit facility
On March 9, 2012, the Company entered into a $400,000 four-year unsecured credit facility with various counter parties as co-documentation agents and the lenders party thereto, which provides for letter of credit and revolving credit availability for the Company (the “Four Year Unsecured Facility”) (the full $400,000 of which is available for letters of credit and/or revolving loans). The Four Year Unsecured Facility was provided by a syndicate of commercial banks. Letters of credit under the Four Year Unsecured Facility are available to support obligations in connection with the insurance business of the Company and its subsidiaries. Loans under the Four Year Unsecured Facility are available for the general corporate and working capital purposes of the Company. The Company may request that existing lenders under the Four Year Unsecured Facility or prospective additional lenders agree to make available additional commitments from time to time so long as the aggregate commitments under the Four Year Unsecured Facility do not exceed $500,000.
Also on March 9, 2012, the Company entered into a $525,000 four-year secured credit facility, with the same parties, which provides for letter of credit availability for the Company (the “Four Year Secured Facility” and together with the Four Year Unsecured Facility, the “Credit Facilities”). The Four Year Secured Facility was also provided by a syndicate of commercial banks. Letters of credit under the Four Year Secured Facility will be available to support obligations in connection with the insurance business of the Company. The Company may request that existing lenders under the Four Year Secured Facility or prospective additional lenders agree to make available additional commitments from time to time so long as the aggregate commitments under the Four Year Secured Facility do not exceed $700,000. The obligations of the Company under the Four Year Secured Facility are secured by cash and securities deposited into cash collateral accounts from time to time with The Bank of New York Mellon.
As of December 31, 2014, there were $276,455 in outstanding letters of credit under the Four Year Secured Facility (December 31, 2013: $358,567) and $nil (2013: $nil) outstanding under the Four Year Unsecured Facility.
The Credit Facilities contain covenants that include, among other things (i) the requirement that the Company initially maintain a minimum level of consolidated net worth of at least $2,600,000 and, commencing with the end of the fiscal quarter ending March 31, 2012, to be increased quarterly by an amount equal to 50.0% of the Company’s consolidated net income (if positive) for such quarter plus 50.0% of the aggregate increases in the consolidated shareholders’ equity of the Company during such fiscal quarter by reason of the issuance and sale of common equity interests of the Company, including upon any conversion of debt securities of the Company into such equity interests, (ii) the requirement that the Company maintain at all times a consolidated total debt to consolidated total capital ratio not greater than 0.35:1.00, and (iii) the requirement that Validus Reinsurance, Ltd. and any other material insurance subsidiaries maintain a financial strength rating by A.M. Best of not less than “B++” (Fair).  In addition, the Credit Facilities contain customary negative covenants applicable to the Company, including limitations on the ability to pay dividends and other payments in respect of equity interests at any time that the Company is otherwise in default with respect to certain provisions under the respective Credit Facilities, limitations on the ability to incur liens, sell assets, merge or consolidate with others, enter into transactions with affiliates, and limitations on the ability of its subsidiaries to incur indebtedness. The Credit Facilities also contain customary affirmative covenants, representations and warranties and events of default for credit facilities of its type. As of December 31, 2014, and throughout the reporting periods presented, the Company was in compliance with all covenants and restrictions under the Credit Facilities.
ii.	$25,000 Talbot FAL facility
On November 19, 2013, Validus Holdings, Ltd. (“Validus Holdings”), as Guarantor, and its wholly-owned subsidiary, Talbot Holdings Ltd. (“Talbot Holdings”), as Borrower, entered into an Amendment and Restatement Agreement relating to its $25,000 Funds-at-Lloyd’s Standby Letter of Credit Facility (the “Facility”) which amends the Facility to support underwriting capacity provided to Talbot 2002 Underwriting Ltd through Syndicate 1183 at Lloyd’s of London for the 2014, 2015 and prior underwriting years of account (the “Restated Facility”). The Restated Facility was provided and arranged by Lloyds Bank plc and INGBank N.V., London Branch. The Restated Facility provides for the issuance of up to $25,000 (denominated in US Dollars or Pound Sterling) of secured letters of credit to be issued for the benefit of Lloyd’s of London. The existing $25,000 secured letter of credit will be extended to provide for an extended termination date covering the 2014, 2015 and prior underwriting years of account under the Restated Facility.
The Restated Facility contains affirmative covenants that include, among other things, (i) the requirement that Validus Holdings and its subsidiaries initially maintain a minimum level of consolidated net worth of at least $3,225,727, and commencing with the fiscal quarter ending September 30, 2013, to be increased quarterly by an amount equal to 50% of our consolidated net income (if positive) for such quarter plus 50% of the aggregate increases in our consolidated shareholder’s equity interests by reason of issuance and sale of Validus Holdings’ common equity interests including upon any conversion of Validus Holdings’ debt securities into equity interests during such quarter and (ii) the requirement that Validus Holdings and its subsidiaries maintain at all times a consolidated total debt to consolidated total capitalization ratio not greater than 0.35:1.00. The Restated Facility defines net worth to include preferred and preference securities and “hybrid” securities (which includes Validus Holdings’ and its Flagstone subsidiaries’ Junior Subordinated Deferrable Debentures). The Restated Facility also requires that Talbot Holdings maintain at least $300,000 of its own Funds at Lloyd’s, and to obtain a letter of comfort from Lloyd’s of London confirming that Lloyd’s of London will take into account a requested order of drawdown to drawdown Talbot Holdings’ own Funds at Lloyd’s ahead of letters of credit issued under the Facility.
The Restated Facility also contains restrictions on Validus Holdings’ ability to pay dividends and other payments in respect of equity interests at any time that it is otherwise in default under the Facility (with certain exceptions for dividends in respect of preferred securities and hybrid securities, which are only limited during the continuance of certain specified defaults), incur debt at its subsidiaries level, transact with affiliates, incur liens, sell assets and merge or consolidate with others and other restrictions customary for transactions of this type, in each case subject to agreed exceptions.
Secured letter of credit availability under the Restated Facility is subject to a borrowing base limitation comprised of (a) the aggregate amount of cash and eligible securities owned by Validus Reinsurance, Ltd. and placed in a collateral account subject to a customary account control agreement in favor of the lenders and agents under the Restated Facility multiplied by (b) an agreed upon advance rate applicable for each category of cash and eligible securities. Obligations in respect of secured letters of credit under the Restated Facility are secured by a first-priority security interest on the cash and eligible securities comprising the borrowing base in favor of the trustee under the Restated Facility.
The Restated Facility contains representations and warranties customary for facilities of this type. The Restated Facility also contains customary events of default including without limitation, with agreed grace periods and thresholds, failure to make payments due under the Restated Facility, material inaccuracy of representations and warranties, breach of covenants, cross defaults to material indebtedness, bankruptcy defaults, judgments defaults, and failure to maintain certain material insurance licenses.
As of December 31, 2014, the Company had $25,000 (December 31, 2013: $25,000) in outstanding letters of credit under the Talbot FAL facility.
As of December 31, 2014, and throughout the reporting periods presented, the Company was in compliance with all covenants and restrictions under the Talbot FAL facility.
iii.	$40,000 IPC bi-lateral facility
The Company assumed an existing evergreen letter of credit facility through the acquisition of IPC Holdings, Ltd. (the “IPC bi-lateral facility”). As of December 31, 2014, there were $15,897 outstanding letters of credit issued under the IPC bi-lateral facility (December 31, 2013: $20,177). As of December 31, 2014, and throughout the reporting periods presented, the Company was in compliance with all covenants and restrictions under the IPC bi-lateral facility.
iv.	$200,000 secured bi-lateral letter of credit facility
The Company is party to an evergreen secured bi-lateral letter of credit facility with Citibank Europe plc (the “Secured bi-lateral letter of credit facility”). As of December 31, 2014, $15,649 (December 31, 2013: $16,726) of letters of credit were outstanding under the Secured bi-lateral letter of credit facility. The Secured bi-lateral letter of credit facility has no fixed termination date and as of December 31, 2014, and throughout the reporting periods presented, the Company is in compliance with all terms and covenants thereof.
v.	$10,000 PaCRe senior secured letter of credit facility
On May 11, 2012, PaCRe and its subsidiary, PaCRe Investments, Ltd. entered into a secured evergreen credit and letter of credit facility with JPMorgan Chase Bank, N.A. This facility provides for revolving borrowings by PaCRe and for letters of credit issued by PaCRe to be used to support its reinsurance obligations in aggregate amount of $10,000. As of December 31, 2014, $294 (December 31, 2013: $294) of letters of credit were outstanding under this facility. As of December 31, 2014, and throughout the reporting periods presented, PaCRe was in compliance with all covenants and restrictions thereof.
vi.	$30,000 AlphaCat Re secured letter of credit facility
In 2013, AlphaCat Re entered into a secured evergreen letter of credit facility with Comerica Bank. This facility provided for letters of credit issued by AlphaCat Re to be used to support its reinsurance obligations in the aggregate amount of $24,800. During the period ended March 31, 2014 the size of the facility was increased to $30,000 from $24,800. As of December 31, 2014, $30,000 (December 31, 2013: $24,800) of letters of credit were outstanding under this facility. As of December 31, 2014, and throughout the reporting periods presented, AlphaCat Re was in compliance with all covenants and restrictions thereof.
vii.	$375,000 Flagstone bi-lateral facility
As part of the Flagstone Acquisition, the Company assumed an evergreen Letters of Credit Master Agreement between Citibank Europe Plc and Flagstone Reassurance Suisse, S.A. (the “Flagstone Bi-Lateral Facility”). At December 31, 2014, the Flagstone Bi-Lateral Facility had $198,389 (December 31, 2013: $305,686) letters of credit issued and outstanding. As of December 31, 2014, and throughout the reporting periods presented, the Company was in compliance with all covenants and restrictions under the Flagstone Bi-Lateral Facility.
(d)	Finance expenses
Finance expenses consist of interest on the junior subordinated deferrable debentures and senior notes, the amortization of debt offering costs, credit facilities fees, bank charges, AlphaCat financing fees and Talbot FAL costs as follows:
	Year Ended
	December 31,			December 31,				December 31,
	2014			2013				2012
2006 Junior Subordinated Deferrable Debentures	$	8,868		$	8,868			$	6,964
2007 Junior Subordinated Deferrable Debentures	7,341			7,341				8,922
Flagstone 2006 Junior Subordinated Deferrable Debentures	9,001			8,259				459
Flagstone 2007 Junior Subordinated Deferrable Debentures	7,129			6,222				327
2010 Senior Notes due 2040	22,388			22,388				22,388
Credit facilities	5,516			6,544				11,999
Bank charges	427			507				269
AlphaCat ILS funds fees (a)	3,530			3,866				2,432
Talbot FAL Facility	(346		)	182				97
Total finance expenses	$	63,854		$	64,177			$	53,857
(a)	Includes finance expenses incurred by AlphaCat Managers, Ltd. in relation to fund raising for the AlphaCat ILS funds, AlphaCat 2015, AlphaCat 2014 and AlphaCat 2013.

Income_taxes

Income taxes	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Income taxes	Income taxes
	The Company provides for income taxes based upon amounts reported in the financial statements and the provisions of currently enacted tax laws. The Company is registered in Bermuda and is subject to Bermuda law with respect to taxation. Under current Bermuda law, the Company is not taxed on any Bermuda income or capital gains and has received an undertaking from the Bermuda Minister of Finance that, in the event of any Bermuda income or capital gains taxes being imposed, the Company will be exempt from such taxes until March 31, 2035.
	The Company has subsidiaries and branches with operations in several jurisdictions outside Bermuda, including but not limited to the United Kingdom (U.K.), the United States (U.S.), Switzerland, Luxembourg and Canada that are subject to relevant taxes in those jurisdictions. Within Note 25 "Segment information" of these Consolidated Financial Statements, gross premiums written are allocated to the territory of coverage exposure and therefore do not correlate to pre-tax income generated in any of the territories identified.
	The Company’s income (loss) before income tax for the years ended December 31, 2014, 2013 and 2012 was generated in the following jurisdictions:
		Years Ended
		December 31, 2014			December 31, 2013				December 31, 2012
	Income before tax—Bermuda	$	496,840		$	601,583			$	369,675
	Income before tax—United Kingdom	10,824			4,668				10,277
	(Loss) income before tax—United States	(11,752		)	(464		)		3,075
	Income (loss) before tax—Switzerland	9,941			(225		)		(3,381		)
	Income before tax—Canada	2,773			57				391
	Income (loss) before tax—Other	29,076			(8,401		)		2,502
	Income before tax—Total	$	537,702		$	597,218			$	382,539
	Income tax expense (benefit) is comprised of current and deferred tax. Income tax expense (benefit) is as follows:
		Years Ended
		December 31, 2014			December 31, 2013				December 31, 2012
	Current income tax expense (benefit)
	U.S.	$	21,257		$	—			$	(54	)
	Non-U.S.	26,179			1,781				1,382
	Total current income tax expense	$	47,436		$	1,781			$	1,328
	Deferred income tax (benefit) expense
	U.S.	$	(24,998	)	$	880			$	134
	Non-U.S.	(22,283		)	(2,278		)		1,039
	Total deferred income tax (benefit) expense	$	(47,281	)	$	(1,398	)		$	1,173
	Total income tax expense (benefit)
	U.S.	$	(3,741	)	$	880			$	80
	Non-U.S.	3,896			(497		)		2,421
	Total income tax expense	$	155		$	383			$	2,501
	The table below is a reconciliation of the actual income tax expense for the years ended December 31, 2014, 2013 and 2012 to the amount computed by applying the effective tax rate of 0% under Bermuda law to income before taxes:
		Years Ended
		December 31, 2014			December 31, 2013				December 31, 2012
	Expected tax expense at Bermuda statutory rate of 0%	$	—		$	—			$	—
	Foreign tax rate differential	7,993			(2,399		)		4,882
	Change in valuation allowance	(7,284		)	4,967				—
	Tax exempt income and expenses not deductible	(6,055		)	(263		)		—
	Share compensation tax windfall	3,513			—				—
	Impact of enacted changes in tax rates	250			(407		)		(1,611		)
	Prior years tax adjustments	666			(461		)		(770		)
	Other	1,072			(1,054		)		—
	Actual income tax expense	$	155		$	383			$	2,501
	Deferred tax assets and liabilities primarily represent the tax effect of temporary differences between the carrying value of assets and liabilities for financial statement purposes and such values as measured by tax laws and regulations in countries in which the operations are taxable. Deferred tax assets may also represent the tax effect of tax loss carryforwards
	In assessing whether deferred tax assets can be realized, the Company considers whether it is more likely than not that the tax benefit of the deferred tax asset will be realized. The realization of deferred tax assets is dependent upon the generation of future taxable income in the period during which those temporary differences and tax loss carryforwards become deductible. The Company considers the reversal of the deferred tax liabilities and projected future taxable income in making this assessment. The amount of the deferred tax asset considered realizable could be reduced in the future if estimates of future taxable income are reduced.
	Significant components of the Company’s deferred tax assets and liabilities at December 31, 2014 and 2013 were as follows:
		Years Ended
		December 31, 2014			December 31, 2013
	Deferred tax asset
	Tax losses carried forward	$	158,789		$	185,955
	Deferred compensation	5,527			6,119
	Tax credits carried forward	4,016			—
	Discounting of loss reserves	13,721			—
	Risk premium reserve	3,842			—
	Unearned premiums reserve	8,505			—
	Pension	5,864			—
	Other	6,023			128
	Deferred tax asset, gross of valuation allowance	206,287			192,202
	Valuation allowance	158,099			177,656
	Net deferred tax asset	$	48,188		$	14,546
	Deferred tax liability
	Lloyd's underwriting profit taxable in future periods	$	636		$	28,945
	Deferred acquisition costs	3,348			—
	Intangibles	8,638			—
	Unrealized appreciation on investments	9,101			—
	Properties and fixed assets	4,993			3,179
	Other	3,192			1,508
Deferred tax liability	29,908			33,632
Net deferred tax asset (liability)	$	18,280		$	(19,086	)
The Company has undistributed earnings in several foreign subsidiaries. If such earnings were to be distributed, as dividends or otherwise, they may be subject to income and withholding taxes. As a general rule, the Company will try to only distribute earnings that can be distributed in a tax free manner and indefinitely reinvest any other earnings. Determination of the amount of unrecognized deferred tax liability related to these earnings is not practicable due to different possible methods for repatriating earnings.
As of December 31, 2014, the Company had net operating and capital loss carry forwards inclusive of cumulative currency translation adjustments as follows:
Tax Jurisdiction		Losses carried forward		Tax effect			Expiration
United Kingdom		547		118			None
United States		6,634		2,322			2029 - 2033
Switzerland		267,420		56,426			2018 - 2020
Luxembourg		340,245		99,352			None
Singapore		5,723		572			None
The valuation allowance as at December 31, 2014 of $158,099 (2013: $177,656), relates to tax loss carry forwards of subsidiaries in Switzerland, Luxembourg, and the United States. The Company believes it is necessary to establish a full valuation allowance against the tax assets primarily related to losses of its Swiss and Luxembourg operations due to uncertainty regarding the ability of these operations to generate sufficient future taxable income to utilize the loss carryforwards and realize the deferred tax assets. There was no change in the position taken during the years ended December 31, 2014, 2013 or 2012.
At December 31, 2014 and 2013, the Company has no accrued liabilities for tax, interest and penalties relating to uncertain tax positions.
The Company has open examinations by the U.K. HM Revenue and Customs for the tax year 2012 and by the New York State Department of Taxation and Finance for tax years 2011 to 2013. The Company believes that these examinations will be concluded within the next 36 months. The Company has open tax years that are potentially subject to examinations by local tax authorities, in the following major tax jurisdictions: the United Kingdom, 2013 and 2014; the United States, 2011 to 2014; Switzerland, 2010 to 2014; and Canada, 2010 to 2014.

Accumulated_other_comprehensiv

Accumulated other comprehensive (loss)	12 Months Ended
	Dec. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Abstract]
Accumulated other comprehensive (loss)	Accumulated other comprehensive (loss)
	The changes in accumulated other comprehensive loss, by component for the years ended December 31, 2014, 2013 and 2012 are as follows:
		Foreign currency items			Decrease in minimum pension liability			Gains and losses on cash flow hedge			Total
	Balance, net of tax December 31, 2011	$	(6,601	)	$	—		$	—		$	(6,601	)
	Net current period other comprehensive income, net of tax	3,648			—			—			3,648
	Balance, net of tax December 31, 2012	$	(2,953	)	$	—		$	—		$	(2,953	)
	Amounts reclassified to retained earnings	4,290			—			—			4,290
	Net current period other comprehensive loss, net of tax	(1,954		)	—			—			(1,954		)
	Balance, net of tax December 31, 2013	$	(617	)	$	—		$	—		$	(617	)
	Net current period other comprehensive loss, net of tax	(7,501		)	(210		)	(228		)	(7,939		)
	Balance, net of tax December 31, 2014	$	(8,118	)	$	(210	)	$	(228	)	$	(8,556	)

Commitments_and_contingencies

Commitments and contingencies	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Commitments and contingencies	Commitments and contingencies
	(a)	Concentrations of credit risk
	The Company attempts to limit its credit exposure by purchasing high quality fixed income investments to maintain a minimum weighted-average portfolio credit rating of A+. In addition, the portfolio limits the amount of “risk assets,” such as non-investment grade debt and equity securities, to a maximum of 35% of shareholders’ equity. The Company also limits its exposure to any single issuer to 3.5% of its investment portfolio or less, excluding government and agency securities, depending on the credit rating of the issuer. With the exception of the Company's bank loan portfolio, which represents 6.1% of the Company's total investments as at December 31, 2014, and certain capital securities issued by investment grade corporations, the minimum credit rating of any security purchased is Baa3/BBB-. In total, investments in below investment grade securities are limited to no more than 10% of the Company's investment portfolio. Excluding bank loans, 2.8% of the portfolio had a split rating below Baa3/BBB- as at December 31, 2014. The Company did not have an aggregate exposure to any single issuer of more than 1.0% of its investment portfolio, other than with respect to government and agency securities as at December 31, 2014.
	The Company underwrites a significant amount of its reinsurance business through three particular brokers as set out below. There is credit risk associated with payments of insurance and reinsurance balances to the Company if these brokers are unable to fulfill their contractual obligations. These companies are large, well established, and there are no indications they are financially distressed. There were no other brokers or parties insured or reinsured that accounted for more than 10% of gross premiums written for the periods mentioned.
	The following table shows the percentage of gross premiums written by broker for the years ended December 31, 2014, 2013 and 2012:
		Years Ended
		December 31, 2014		December 31, 2013			December 31, 2012
	Marsh & McLennan	28.5	%	21.8	%		30.1	%
	Aon Benfield Group Ltd.	20.1	%	27.7	%		24.2	%
	Willis Group Holdings Ltd.	18	%	19.4	%		16.4	%
	(b)	Employment agreements
	The Company has entered into employment agreements with certain individuals that provide for executive benefits and severance payments under certain circumstances.
	(c)	Operating leases
	The Company leases office space and office equipment under operating leases. Total rent expense with respect to these operating leases for the year ended December 31, 2014 was approximately $10,540 (2013: $10,214, 2012: $7,670). Future minimum lease commitments are as follows:
	2015	$	11,094
	2016	8,616
	2017	7,514
	2018	7,350
	2019	7,130
	2020 and thereafter	23,784
		$	65,488
	(d)	Funds at Lloyd’s
	The amounts provided under the Talbot FAL Facility would become a liability of the Company in the event of Syndicate 1183 declaring a loss at a level which would call on this arrangement.
	Talbot operates in Lloyd’s through a corporate member, Talbot 2002 Underwriting Capital Ltd (“T02”), which is the sole participant in Syndicate 1183. Lloyd’s sets T02’s required capital annually based on Syndicate 1183’s business plan, rating environment and reserving environment together with input arising from Lloyd’s discussions with, inter alia, regulatory and rating agencies. Such capital, called Funds at Lloyd’s (“FAL”), comprises: cash, investments and undrawn letters of credit provided by various banks.
	The amounts of cash, investments and letters of credit provided for each year of account as follows:
		2015 Underwriting Year			2014 Underwriting Year				2013 Underwriting Year
	Talbot FAL facility	$	25,000		$	25,000			$	25,000
	Group funds	570,100			450,000				403,700
	Total	$	595,100		$	475,000			$	428,700
	The amounts which are provided as FAL are not available for distribution to the Company for the payment of dividends. Talbot’s corporate member may also be required to maintain funds under the control of Lloyd’s in excess of its capital requirement and such funds also may not be available for distribution to the Company for the payment of dividends. See Note 7 (d) for investments pledged as collateral.
	(e)	Lloyd’s Central Fund
	Whenever a member of Lloyd’s is unable to pay its debts to policyholders, such debts may be payable by the Lloyd’s Central Fund. If Lloyd’s determines that the Central Fund needs to be increased, it has the power to assess premium levies on current Lloyd’s members up to 3% of a member’s underwriting capacity in any one year. The Company does not believe that any assessment is likely in the foreseeable future and has not provided any allowance for such an assessment. However, based on the Company’s 2015 estimated premium income at Lloyd’s of £625,000, the December 31, 2014 exchange rate of £1 equals $1.5578 and assuming the maximum 3% assessment, the maximum the Company could be assessed as a levy would be approximately $29,209.
	(f)	Investment in affiliate commitments
	As discussed in Note 9 "Investments in affiliates," on December 20, 2011 the Company entered into an Assignment and Assumption Agreement with Aquiline Capital Partners LLC, pursuant to which it assumed total capital commitments of $50,000. This interest is governed by the terms of an Amended and Restated Exempted Limited Partnership Agreement dated as of January 9, 2013. The Company’s remaining commitment at December 31, 2014 was $7,500 (December 31, 2013: $17,890).
	On October 2, 2014, the Company assumed an additional investment in Aquiline Capital Partners II GP (Offshore) Ltd. as part of the Western World acquisition representing a total capital commitment of $10,000. This interest is governed by the terms of an Amended and Restated Exempted Limited Partnership Agreement dated as of January 9, 2013. The Company's remaining capital commitment at December 31, 2014 was $1,499.
	On November 7, 2014 the Company entered into a Subscription Agreement with Aquiline Capital Partners III GP (Offshore) Ltd., pursuant to which it assumed total capital commitments of $100,000 in respect of Limited Partnership Interests in Aquiline Financial Services Fund III L.P. (the "Fund"). The Limited Partnership Interests are governed by the terms of the Aquiline III Limited Partnership Agreement dated November 7, 2014. The Company’s remaining commitment at December 31, 2014 was $100,000.
	On December 29, 2014, the Company entered into an agreement with AlphaCat 2015 pursuant to which it assumed total capital commitments of $28,000. The Company’s remaining commitment at December 31, 2014 was $2,400.
	On December 29, 2014, the Company entered into an agreement with an AlphaCat ILS fund pursuant to which it assumed total capital commitments of $20,000. The Company’s remaining commitment at December 31, 2014 was $8,000.
	(g)	Fixed maturity commitment
	As at December 31, 2014, the Company had an outstanding commitment to participate in certain revolver loan facilities through participation agreements with an established loan originator. The undrawn amount under the revolver facility participations as at December 31, 2014 was $7,539.
	(h)	Other investment commitments
	At December 31, 2014, the Company had capital commitments in other investments of $153,000 (December 31, 2013: $30,000). The Company's remaining commitment to these investments at December 31, 2014 was $83,712 (December 31, 2013: $5,045).
	(i)	Multi-Beneficiary Reinsurance Trusts
	In December 2014, the Company established a MBRT to collateralize its (re)insurance liabilities associated with and for the benefit of U.S. domiciled cedants, and was approved as a trusteed reinsurer in the State of New Jersey. As a result, cedants domiciled in that state will receive automatic credit in their regulatory filings for the reinsurance provided prospectively by the Company.
	(j)	Structured settlements
	As at December 31, 2014, the Company is contingently liable for the present value of amounts not yet due under annuities purchased by Western World where the claimant is the payee for the amount of $3,412.
	(k)	Income tax examinations
	The Company has open examinations by the U.K. HM Revenue and Customs for the tax year 2012 and by the New York State Department of Taxation and Finance for tax years 2011 to 2013. The Company believes that these examinations will be concluded within the next 36 months. For further details refer to Note 20 "Income taxes" to the Consolidated Financial Statements.

Related_party_transactions

Related party transactions	12 Months Ended
	Dec. 31, 2014
Related Party Transactions [Abstract]
Related party transactions	Related party transactions
	The transactions listed below are classified as related party transactions as each counter party has either a direct or indirect shareholding in the Company.
	Aquiline Capital Partners, LLC and its related companies ("Aquiline"), which own 523,180 shares in the Company, hold warrants to purchase 2,756,088 shares, and have two employees on the Company's Board of Directors who do not receive compensation from the Company, are shareholders of Group Ark Insurance Holdings Ltd. ("Group Ark"). Christopher E. Watson, a director of the Company, serves as a director of Group Ark. Pursuant to reinsurance agreements with a subsidiary of Group Ark, the Company recognized gross premiums written during the year ended December 31, 2014 of $2,073 (2013: $2,899, 2012: $7,582) respectively, with $335 included in premiums receivable at December 31, 2014 (December 31, 2013: $238). The Company also recognized reinsurance premiums ceded during the year ended December 31, 2014 of $126 (2013: $85, 2012: $90) and had reinsurance balances payable of $4 at December 31, 2014 (December 31, 2013: $4). The Company recorded $1,063 of loss reserves recoverable at December 31, 2014 (December 31, 2013: $3,698). Earned premium adjustments of $1,982 were recorded during the year ended December 31, 2014 (2013: $2,911, 2012: $7,625).
	On November 24, 2009, the Company entered into an Investment Management Agreement with Conning, Inc. ("Conning") to manage a portion of the Company's investment portfolio. Aquiline acquired Conning on June 16, 2009. Jeffrey W. Greenberg, a director of the Company, serves as a director of Conning Holdings Corp., the parent company of Conning. Investment management fees earned by Conning for the year ended December 31, 2014 were $1,125 (2013: $500, 2012: $809), with $515 included in accounts payable and accrued expenses at December 31, 2014 (December 31, 2013: $283).
	On December 20, 2011, the Company entered into an Assignment and Assumption Agreement (the "Agreement") with Aquiline Capital Partners LLC, a Delaware limited liability company (the "Assignor") and Aquiline Capital Partners II GP (Offshore) Ltd., a Cayman Islands company limited by shares (the "General Partner") pursuant to which the Company has assumed 100% of the Assignor's interest in Aquiline Financial Services Fund II L.P. (the "Aquiline II Partnership") representing a total capital commitment of $50,000 (the "Aquiline II Commitment"), as a limited partner in the Partnership (the "Transferred Interest"). On October 2, 2014, the Company assumed an additional investment in the Aquiline II Partnership as part of the Western World acquisition representing a total capital commitment of $10,000. Messrs. Greenberg and Watson, directors of the Company, serve as managing principal and senior principal, respectively, of Aquiline Capital Partners LLC. For the year ended December 31, 2014, the Company incurred $342 (2013: $1,236, 2012: $2,979) in partnership fees and made capital contributions of $12,468 (2013: $14,492, 2012: $14,365), with $nil included in accounts payable and accrued expenses at December 31, 2014 (December 31, 2013: $nil).
	On November 7, 2014, the Company, entered into a Subscription Agreement (the "Subscription Agreement") with Aquiline Capital Partners III GP (Offshore) Ltd., a Cayman Islands company limited by shares (the "Aquiline III General Partner") pursuant to which the Company is committing and agreeing to purchase limited partnership or other comparable limited liability equity interests (the "Limited Partnership Interests") in Aquiline Financial Services Fund III L.P., a Cayman Islands exempted limited partnership (the "Aquiline III Partnership"), and/or one or more Alternative Investment Vehicles and Intermediate Entities (together with the Aquiline III Partnership, the "Fund" or the "Entities") with a capital commitment (the "Aquiline III Commitment") in an amount equal to $100,000, as a limited partner in the Aquiline Financial Services III Partnership. For the year ended December 31, 2014, the Company incurred no partnership fees and made no capital contributions.
	Certain shareholders of the Company and their affiliates, as well as employers of entities associated with directors or officers have purchased insurance and/or reinsurance from the Company in the ordinary course of business. The Company believes these transactions were settled for arm's length consideration.

Earnings_per_share

Earnings per share	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Earnings per share	Earnings per share
	The following table sets forth the computation of basic earnings per share and earnings per diluted share available to common shareholders for the years ended December 31, 2014, 2013 and 2012:
		Years Ended
		December 31, 2014			December 31, 2013			December 31, 2012
	Basic earnings per share
	Net income	$	445,871		$	542,361		$	392,618
	Loss (income) attributable to noncontrolling interest	35,464			(9,695		)	15,820
	Net income available to Validus	$	481,335		$	532,666		$	408,438
	Less: Dividends and distributions declared on outstanding warrants	(6,208		)	(19,214		)	(6,693		)
	Income available to common shareholders	$	475,127		$	513,452		$	401,745
	Weighted average number of common shares outstanding	90,354,745			102,202,274			97,184,110
	Basic earnings per share available to common shareholders	$	5.26		$	5.02		$	4.13
	Earnings per diluted share
	Net income	$	445,871		$	542,361		$	392,618
	Loss (income) attributable to noncontrolling interest	35,464			(9,695		)	15,820
	Net income available to Validus	$	481,335		$	532,666		$	408,438
	Less: Dividends and distributions declared on outstanding warrants	—			(19,214		)	—
	Income available to common shareholders	$	481,335		$	513,452		$	408,438
	Weighted average number of common shares outstanding	90,354,745			102,202,274			97,184,110
	Share equivalents:
	Warrants	2,789,032			—			3,137,956
	Stock options	745,561			1,026,543			769,618
	Unvested restricted shares	800,933			741,472			1,293,239
	Weighted average number of diluted common shares outstanding	94,690,271			103,970,289			102,384,923
	Earnings per diluted share available to common shareholders	$	5.08		$	4.94		$	3.99
	Share equivalents that would result in the issuance of common shares of 199,740, 366,821 and 199,446 were outstanding for the years ended December 31, 2014, 2013 and 2012, respectively but were not included in the computation of earnings per diluted share because the effect would be antidilutive.

Segment_information

Segment information	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Segment information	Segment information
	The Company conducts its operations worldwide through four operating segments, which have been determined under U.S. GAAP segment reporting to be Validus Re, AlphaCat, Talbot and Western World. During the first quarter of 2012, to better align the Company’s operating and reporting structure with its current strategy, there was a change in the segment structure. This change included the AlphaCat group of companies as a separate operating segment. The AlphaCat segment currently includes the Company’s investments in AlphaCat Re 2011, AlphaCat Re 2012, AlphaCat 2013, AlphaCat 2014, AlphaCat 2015, PaCRe, the AlphaCat ILS funds and the BetaCat ILS funds. The Company’s operating segments are strategic business units that offer different products and services. They are managed and have capital allocated separately because each segment requires different strategies.
	Validus Re Segment
	The Validus Re segment is focused on short-tail lines of reinsurance. The primary lines in which the segment conducts business are property, marine and specialty which includes agriculture, aerospace and aviation, financial lines of business, nuclear, terrorism, life, accident & health, workers’ compensation, crisis management, contingency, motor, technical lines, composite and trade credit.
	AlphaCat Segment
	The AlphaCat segment manages strategic relationships that leverage the Company’s underwriting and investment expertise and earns management, performance and underwriting fees primarily from the Company’s operating affiliates, AlphaCat Re 2011, AlphaCat Re 2012, AlphaCat 2013, AlphaCat 2014 and AlphaCat 2015, as well as PaCRe, the AlphaCat ILS funds and the BetaCat ILS funds.
	Talbot Segment
	The Talbot segment focuses on a wide range of marine and energy, war, political violence, commercial property, financial institutions, contingency, accident & health and aviation classes of business on an insurance or facultative reinsurance basis and principally property, aerospace and marine classes of business on a treaty reinsurance basis.
	Western World Segment
	The Western World segment is focused on providing commercial insurance products on a surplus lines and specialty admitted basis. Western World specializes in underwriting classes of business that are not easily placed in the standard insurance market due to their complexity, high hazard, or unusual nature; including general liability, property and professional liability classes of business.
	Corporate and eliminations
	The Company has a corporate function ("Corporate"), which includes the activities of the parent company, and which carries out certain functions for the group. Corporate includes ‘non-core’ underwriting expenses, predominantly general and administrative and stock compensation expenses. Corporate also denotes the activities of certain key executives such as the Chief Executive Officer and Chief Financial Officer. For internal reporting purposes, corporate is reflected separately, however corporate is not considered an operating segment under these circumstances. Other reconciling items include, but are not limited to, the elimination of inter segment revenues and expenses and unusual items that are not allocated to segments. Corporate also includes the gain on bargain purchase, net of expenses in connection with the acquisition of Flagstone in 2012 and transaction expenses related to the Western World acquisition in 2014.
	The following tables summarize the results of our operating segments and "Corporate":
	Year Ended December 31, 2014		Validus Re Segment				AlphaCat Segment				Talbot Segment				Western World Segment (d)				Corporate & Eliminations				Total
	Underwriting income
	Gross premiums written		$	1,136,910			$	135,181			$	1,101,770			$	65,235			$	(75,810	)		$	2,363,286
	Reinsurance premiums ceded		(182,056		)		(4,348		)		(192,211		)		(6,428		)		75,810				(309,233		)
	Net premiums written		954,854				130,833				909,559				58,807				—				2,054,053
	Change in unearned premiums		(37,570		)		1,517				(29,785		)		14,189				—				(51,649		)
	Net premiums earned		917,284				132,350				879,774				72,996				—				2,002,404
	Underwriting deductions
	Losses and loss expenses		307,290				(9,670		)		423,394				51,035				—				772,049
	Policy acquisition costs		141,670				12,673				187,162				3,169				(4,118		)		340,556
	General and administrative expenses		74,739				19,590				150,828				11,121				73,514				329,792
	Share compensation expenses		9,739				501				11,346				135				11,352				33,073
	Total underwriting deductions		533,438				23,094				772,730				65,460				80,748				1,475,470
	Underwriting income (loss)		$	383,846			$	109,256			$	107,044			$	7,536			$	(80,748	)		$	526,934
	Net investment income		74,599				4,276				20,575				4,523				(3,897		)		100,076
	Other insurance related income (loss)		3,159				27,122				1,095				264				(9,658		)		21,982
	Finance expenses		(14,727		)		(3,545		)		213				—				(45,795		)		(63,854		)
	Operating income (loss) before taxes, income from operating affiliates and (income) attributable to operating affiliate investors		446,877				137,109				128,927				12,323				(140,098		)		585,138
	Tax benefit (expense)		5,512				—				(3,880		)		(1,422		)		(365		)		(155		)
	Income from operating affiliates		—				17,723				—				—				—				17,723
	(Income) attributable to operating affiliate investors		—				(109,399		)		—				—				—				(109,399		)
	Net operating income (loss)		$	452,389			$	45,433			$	125,047			$	10,901			$	(140,463	)		$	493,307
	Net realized gains on investments		7,611				10,935				3,852				697				—				23,095
	Change in net unrealized gains (losses) on investments		8,404				(56,943		)		1,685				(155		)		(10,964		)		(57,973		)
	Income from investment affiliate		8,411				—				—				—				—				8,411
	Foreign exchange (losses) gains		(6,404		)		70				(5,961		)		—				1,665				(10,630		)
	Other (loss)		(2,243		)		—				—				—				—				(2,243		)
	Transaction expenses (a)		—				—				—				—				(8,096		)		(8,096		)
	Net income (loss)		$	468,168			$	(505	)		$	124,623			$	11,443			$	(157,858	)		$	445,871
	Net loss attributable to noncontrolling interest		—				35,464				—				—				—				35,464
	Net income (loss) available (attributable) to Validus		$	468,168			$	34,959			$	124,623			$	11,443			$	(157,858	)		$	481,335
	Selected ratios (b):
	Net premiums written / Gross premiums written		84		%		96.8		%		82.6		%		90.1		%						86.9		%
	Losses and loss expenses		33.5		%		(7.3		)%		48.1		%		69.9		%						38.6		%
	Policy acquisition costs		15.5		%		9.6		%		21.3		%		4.4		%						17		%
	General and administrative expenses (c)		9.2		%		15.2		%		18.4		%		15.4		%						18.1		%
	Expense ratio		24.7		%		24.8		%		39.7		%		19.8		%						35.1		%
	Combined ratio		58.2		%		17.5		%		87.8		%		89.7		%						73.7		%
	Total assets		$	4,209,289			$	1,656,326			$	2,890,123			$	1,492,179			$	63,704			$	10,311,621
	(a)	The transaction expenses relate to costs incurred in connection with the acquisition of Western World, which was completed on October 2, 2014. Transaction expenses are primarily comprised of legal, financial advisory and audit related services.
	(b)	Ratios are based on net premiums earned.
	(c)	The general and administrative expenses ratio includes share compensation expenses.
	(d)	The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.
	Year Ended December 31, 2013		Validus Re Segment				AlphaCat Segment				Talbot Segment				Corporate & Eliminations				Total
	Underwriting income
	Gross premiums written		$	1,242,522			$	147,009			$	1,091,890			$	(80,315	)		$	2,401,106
	Reinsurance premiums ceded		(226,264		)		(525		)		(226,111		)		80,315				(372,585		)
	Net premiums written		1,016,258				146,484				865,779				—				2,028,521
	Change in unearned premiums		117,679				(9,070		)		(35,085		)		—				73,524
	Net premiums earned		1,133,937				137,414				830,694				—				2,102,045
	Underwriting deductions
Losses and loss expenses		430,026				17,569				346,337				—				793,932
Policy acquisition costs		180,779				13,853				170,738				(5,060		)		360,310
General and administrative expenses		91,260				18,765				136,458				68,782				315,265
Share compensation expenses		7,668				468				9,613				9,881				27,630
Total underwriting deductions		709,733				50,655				663,146				73,603				1,497,137
Underwriting income (loss)		$	424,204			$	86,759			$	167,548			$	(73,603	)		$	604,908
Net investment income		81,346				3,865				18,061				(7,200		)		96,072
Other insurance related income (loss)		19,222				26,424				1,819				(28,345		)		19,120
Finance expenses		(16,111		)		(5,734		)		(259		)		(42,073		)		(64,177		)
Operating income (loss) before taxes, income from operating affiliates and (income) attributable to operating affiliate investors		508,661				111,314				187,169				(151,221		)		655,923
Tax benefit (expense)		272				—				(671		)		16				(383		)
Income from operating affiliates		—				14,289				—				—				14,289
(Income) attributable to operating affiliate investors		—				(68,763		)		—				—				(68,763		)
Net operating income (loss)		$	508,933			$	56,840			$	186,498			$	(151,205	)		$	601,066
Net realized (losses) gains on investments		(1,382		)		4,084				556				—				3,258
Change in net unrealized losses on investments		(41,388		)		(3,893		)		(13,200		)		—				(58,481		)
Income from investment affiliate		4,790				—				—				—				4,790
Foreign exchange gains (losses)		7,394				(816		)		(3,531		)		(542		)		2,505
Other income		(10,777		)		—				—				—				(10,777		)
Net income (loss)		$	467,570			$	56,215			$	170,323			$	(151,747	)		$	542,361
Net (income) attributable to noncontrolling interest		—				(9,695		)		—				—				(9,695		)
Net income (loss) available (attributable) to Validus		$	467,570			$	46,520			$	170,323			$	(151,747	)		$	532,666
Selected ratios (a):
Net premiums written / Gross premiums written		81.8		%		99.6		%		79.3		%						84.5		%
Losses and loss expenses		37.9		%		12.8		%		41.7		%						37.8		%
Policy acquisition costs		16		%		10.1		%		20.5		%						17.1		%
General and administrative expenses (b)		8.7		%		14		%		17.6		%						16.3		%
Expense ratio		24.7		%		24.1		%		38.1		%						33.4		%
Combined ratio		62.6		%		36.9		%		79.8		%						71.2		%
Total assets		$	5,326,076			$	1,558,453			$	2,891,682			$	70,221			$	9,846,432
(a)	Ratios are based on net premiums earned.
(b)	The general and administrative expenses ratio includes share compensation expenses.
Year Ended December 31, 2012		Validus Re Segment				AlphaCat Segment				Talbot Segment				Corporate &				Total
														Eliminations
Underwriting income
Gross premiums written		$	1,131,959			$	21,603			$	1,078,636			$	(65,758	)		$	2,166,440
Reinsurance premiums ceded		(144,578		)		—				(228,686		)		65,758				(307,506		)
Net premiums written		987,381				21,603				849,950				—				1,858,934
Change in unearned premiums		35,890				(3,937		)		(17,671		)		—				14,282
Net premiums earned		1,023,271				17,666				832,279				—				1,873,216
Underwriting deductions
Losses and loss expenses		575,416				—				424,030				—				999,446
Policy acquisition costs		154,362				1,774				183,926				(5,364		)		334,698
General and administrative expenses		63,048				7,532				133,281				59,791				263,652
Share compensation expenses		7,763				279				7,789				10,878				26,709
Total underwriting deductions		800,589				9,585				749,026				65,305				1,624,505
Underwriting income (loss)		$	222,682			$	8,081			$	83,253			$	(65,305	)		$	248,711
Net investment income		88,727				3,748				21,310				(5,849		)		107,936
Other insurance related income (loss)		5,000				23,229				2,033				(7,951		)		22,311
Finance expenses		(8,943		)		(3,061		)		(162		)		(41,691		)		(53,857		)
Operating income (loss) before taxes and income from operating affiliates		307,466				31,997				106,434				(120,796		)		325,101
Tax (expense)		(168		)		—				(2,229		)		(104		)		(2,501		)
Income from operating affiliates		—				12,580				—				—				12,580
Net operating income (loss)		$	307,298			$	44,577			$	104,205			$	(120,900	)		$	335,180
Gain on bargain purchase, net of expenses (a)		—				—				—				17,701				17,701
Net realized gains on investments		12,026				216				5,991				—				18,233
Net unrealized (losses) on investments		35,033				(19,509		)		2,061				—				17,585
Loss from investment affiliate		(964		)		—				—				—				(964		)
Foreign exchange (losses) gains		2,664				44				2,527				(437		)		4,798
Other income		85				—				—				—				85
Net income (loss)		$	356,142			$	25,328			$	114,784			$	(103,636	)		$	392,618
Net loss attributable to noncontrolling interest		—				15,820				—				—				15,820
Net income (loss) available (attributable) to Validus		$	356,142			$	41,148			$	114,784			$	(103,636	)		$	408,438
Selected ratios: (b)
Net premiums written / Gross premiums written		87.2		%		100		%		78.8		%						85.8		%
Losses and loss expenses		56.2		%		—		%		50.9		%						53.4		%
Policy acquisition costs		15.1		%		10		%		22.1		%						17.9		%
General and administrative expenses (c)		6.9		%		44.2		%		16.9		%						15.5		%
Expense ratio		22		%		54.2		%		39		%						33.4		%
Combined ratio		78.2		%		54.2		%		89.9		%						86.8		%
Total assets		$	6,206,084			$	805,513			$	2,968,224			$	40,443			$	10,020,264
(a)	The gain on bargain purchase, net of expenses, arose from the acquisition of Flagstone Reinsurance Holdings S.A. on November 30, 2012 and is net of transaction related expenses which included legal, financial advisory, audit related services and termination expenses.
(b)	Ratios are based on net premiums earned.
(c)	The general and administrative expenses ratio includes share compensation expenses.
The following table sets forth the gross premiums written by line of business for the periods indicated:
		Gross Premiums Written (a)
		Year Ended December 31, 2014				Year Ended December 31, 2013				Year Ended December 31, 2012
Property		$	1,054,530			$	1,164,687			$	1,060,297
Marine		576,478				570,008				649,421
Specialty		677,026				666,411				456,722
Liability		55,252				—				—
		$	2,363,286			$	2,401,106			$	2,166,440
(a)	The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.
The Company’s exposures are generally diversified across geographic zones. The following tables set forth the gross premiums written allocated to the territory of coverage exposure for the periods indicated:
	Gross Premiums Written
	Year Ended December 31, 2014
	Validus Re				AlphaCat				Talbot				Western World (d)				Eliminations				Total				%
United States	$	442,314			$	30,987			$	108,458			$	65,235			$	(11,026	)		$	635,968			27	%
Worldwide excluding United States (a)	76,129				7,331				139,570				—				(1,334		)		221,696				9.4	%
Australia and New Zealand	20,257				1,019				9,736				—				—				31,012				1.3	%
Europe	58,236				3,005				45,615				—				(2,305		)		104,551				4.4	%
Latin America and Caribbean	54,053				—				116,281				—				(23,958		)		146,376				6.2	%
Japan	43,310				608				4,116				—				(608		)		47,426				2	%
Canada	3,670				215				10,194				—				(214		)		13,865				0.6	%
Rest of the world (b)	21,467				—				93,012				—				—				114,479				4.8	%
Sub-total, non United States	277,122				12,178				418,524				—				(28,419		)		679,405				28.7	%
Worldwide including United States (a)	179,564				92,016				96,187				—				(22,463		)		345,304				14.6	%
Other locations non-specific (c)	237,910				—				478,601				—				(13,902		)		702,609				29.7	%
Total	$	1,136,910			$	135,181			$	1,101,770			$	65,235			$	(75,810	)		$	2,363,286			100	%
	Gross Premiums Written
	Year Ended December 31, 2013
	Validus Re				AlphaCat				Talbot				Eliminations				Total				%
United States	$	524,776			$	50,848			$	93,357			$	(6,565	)		$	662,416			27.7	%
Worldwide excluding United States (a)	63,643				14,801				142,294				(1,485		)		219,253				9.1	%
Australia and New Zealand	22,275				2,216				11,097				—				35,588				1.5	%
Europe	65,861				2,533				51,667				(1,446		)		118,615				4.9	%
Latin America and Caribbean	50,522				—				155,798				(52,267		)		154,053				6.4	%
Japan	42,729				653				5,971				(653		)		48,700				2	%
Canada	3,688				818				10,768				(818		)		14,456				0.6	%
Rest of the world (b)	24,337				—				92,652				—				116,989				4.9	%
Sub-total, non United States	273,055				21,021				470,247				(56,669		)		707,654				29.4	%
Worldwide including United States (a)	177,539				75,140				80,538				(8,996		)		324,221				13.5	%
Other locations non-specific (c)	267,152				—				447,748				(8,085		)		706,815				29.4	%
Total	$	1,242,522			$	147,009			$	1,091,890			$	(80,315	)		$	2,401,106			100	%
	Gross Premiums Written
	Year Ended December 31, 2012
	Validus Re				AlphaCat				Talbot				Eliminations				Total				%
United States	$	463,384			$	12,638			$	77,561			$	(1,942	)		$	551,641			25.4	%
Worldwide excluding United States (a)	24,119				279				156,593				—				180,991				8.4	%
Australia and New Zealand	—				217				12,851				—				13,068				0.6	%
Europe	87,805				1,332				50,262				—				139,399				6.4	%
Latin America and Caribbean	80,432				—				149,091				(53,565		)		175,958				8.1	%
Japan	30,386				—				6,630				—				37,016				1.7	%
Canada	—				—				12,243				—				12,243				0.6	%
Rest of the world (b)	68,754				—				91,130				—				159,884				7.4	%
Sub-total, non United States	291,496				1,828				478,800				(53,565		)		718,559				33.2	%
Worldwide including United States (a)	102,080				7,137				65,084				(4,038		)		170,263				7.9	%
Other locations non-specific (c)	274,999				—				457,191				(6,213		)		725,977				33.5	%
Total	$	1,131,959			$	21,603			$	1,078,636			$	(65,758	)		$	2,166,440			100	%
(a)	Represents risks in two or more geographic zones.
(b)	Represents risks in one geographic zone.
(c)	The Other locations non-specific category refers to business for which an analysis of exposure by geographic zone is not applicable, such as marine and aerospace risks, since these exposures can span multiple geographic areas and, in some instances, are not fixed locations.
(d)	The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.

Statutory_and_regulatory_requi

Statutory and regulatory requirements	12 Months Ended
	Dec. 31, 2014
Statutory and regulatory requirements [Abstract]
Statutory and regulatory requirements	Statutory and regulatory requirements
	Validus Holdings, Ltd. has operations which are subject to laws and regulations in the jurisdictions in which they operate, the most significant of which are Bermuda, the United Kingdom, the United States and Switzerland.
	As a holding company, Validus Holdings, Ltd.’s principal sources of income are dividends or other sources of permitted distributions from its subsidiaries. These funds provide the cash flow required for dividend payments to the Company’s shareholders. The holding company has no material restrictions on its ability to make distributions to shareholders however, the ability of our (re)insurance subsidiaries to make distributions is limited by the applicable laws and regulations of the various countries in which we operate. The Company’s subsidiaries are required to maintain certain measures of solvency and liquidity which provide restrictions on declaring dividends and distributions. The statutory capital and surplus in certain of our most significant regulatory jurisdictions as at December 31, 2014 and 2013 was as follows:
		Bermuda (a)				United States (b)				Switzerland (c)
		December 31,				December 31,				December 31,
		2014		2013		2014		2013		2014		2013
	Required statutory capital and surplus	$	586,641	$	1,390,179	$	95,963	$	—	$	205,563	$	312,563
	Actual statutory capital and surplus	3,793,329		3,884,572		452,089		—		701,010		939,609
	(a)	The Company's Bermuda based insurance subsidiaries are required to maintain minimum statutory capital and surplus equal to the greater of a minimum solvency margin ("MSM") and the Enhanced Capital Requirement ("ECR") where applicable. The ECR is equal to the higher of each insurer's MSM or the Bermuda Solvency Capital Requirement ("BSCR") model or approved internal capital model. The BSCR for the relevant insurers for the year ended December 31, 2014 will not be filed with the BMA until April 2015. As a result, the required statutory capital and surplus as at December 31, 2014 is based on the MSM of all relevant insurers, whereas the required statutory capital and surplus as at December 31, 2013 is based on the MSM and ECR where applicable for all relevant insurers. Required statutory capital and surplus includes Validus Reinsurance, Ltd., Validus Reinsurance (Switzerland) Ltd (Bermuda Branch), PaCRe, Ltd., IPCRe Limited, Validus Re Americas, Ltd., Talbot Insurance (Bermuda), Ltd., AlphaCat Reinsurance, Ltd. and Mont Fort Re Ltd. Actual statutory capital and surplus includes Validus Reinsurance, Ltd., AlphaCat Reinsurance, Ltd. and Talbot Insurance (Bermuda), Ltd. Validus Reinsurance, Ltd. is the parent company of the other five Bermuda based insurance subsidiaries.
	(b)	Required statutory capital and surplus is based on the Risk-Based Capital ("RBC") requirements and includes Western World Insurance Company, Tudor Insurance Company and Stratford Insurance Company. Actual statutory capital and surplus includes Western World Insurance Company. Western World Insurance Company is the parent Company of the other two U.S. based insurance subsidiaries. The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.
	(c)	Required statutory capital and surplus is based on the Target Capital ("TC") requirements calculated under the Swiss Solvency Test ("SST"). Required and actual statutory capital and surplus includes Validus Reinsurance (Switzerland) Ltd (formerly Flagstone Réassurance Suisse SA).
	During 2015, the Company's regulated subsidiaries have the ability to distribute up to $1,013,379 of unrestricted net assets as dividend payments and/or return of capital to Validus Holdings, Ltd. (2014: $516,854) without prior regulatory approval. During the year ended December 31, 2014, actual dividends and distributions to Validus Holdings, Ltd. from its subsidiaries were $773,966 (2013: $1,009,000).
	Statutory net income for the years ended December 31, 2014, 2013 and 2012 was as follows:
		Bermuda (a)						United States (b)						Switzerland (c)
		Year ended December 31,						Year ended December 31,						Year ended December 31,
		2014		2013		2012		2014		2013		2012		2014		2013			2012
	Statutory net income (loss)	$	509,559	$	688,001	$	496,227	$	105,210	$	—	$	—	$	60,308	$	(17,655	)	$	(1,559	)
	(a)	Statutory net income includes Validus Reinsurance, Ltd., PaCRe, Ltd. (at the Company's effective 10% equity interest), IPCRe Limited, Validus Re Americas, Ltd., Talbot Insurance (Bermuda), Ltd., AlphaCat Reinsurance, Ltd. and Mont Fort Re Ltd.
	(b)	Statutory net income includes Western World Insurance Company, Tudor Insurance Company and Stratford Insurance Company. The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.
	(c)	Statutory net income (loss) includes Validus Reinsurance (Switzerland) Ltd (formerly Flagstone Réassurance Suisse SA). The results of Validus Reinsurance (Switzerland) Ltd, a former Flagstone subsidiary, have been included in the Company's consolidated results from the November 30, 2012 date of acquisition.
	(a)	Bermuda
	The Company has eight Bermuda based insurance subsidiaries: Validus Reinsurance, Ltd., a Class 4 insurer; Validus Reinsurance (Switzerland) Ltd (Bermuda Branch) (formerly known as Flagstone Réassurance Suisse S.A. (Bermuda Branch)), a Class 4 insurer; PaCRe, Ltd., a Class 4 insurer; IPCRe Limited ("IPCRe") (formerly known as Validus Re Americas, Ltd.), a Class 3A insurer; Validus Re Americas, Ltd. (formerly known as Longhorn Re, Ltd.), a Class 3A insurer; Talbot Insurance (Bermuda), Ltd. ("TIBL"), a Class 3 insurer; AlphaCat Reinsurance, Ltd., a Class 3 insurer; and Mont Fort Re Ltd., a Class 3 insurer. The Company also has investments in two Bermuda based insurance affiliates, AlphaCat Re 2011, Ltd. and AlphaCat Re 2012, Ltd., each licensed as a Special Purpose Insurer (“SPI”) under the Insurance Act. Each of these Bermuda insurance subsidiaries and affiliates is registered under the Insurance Act. The Bermuda subsidiaries have to meet certain requirements for minimum solvency and liquidity ratios and all statutory filings are prepared in accordance with prescribed regulatory accounting practices required by The Insurance Act 1978. At December 31, 2014 and 2013, the actual statutory capital and surplus of the Bermuda based insurance subsidiaries exceeded the relevant regulatory requirements.
	The ability of certain of these subsidiaries to pay dividends to us is limited under Bermuda law and regulations. The Insurance Act provides that each of the Class 4 Bermuda subsidiaries may not declare or pay, in any financial year, dividends of more than 25% of its total statutory capital and surplus (as shown on its statutory balance sheet in relation to the previous financial year) unless it files with the BMA at least seven days prior to the payment, an affidavit signed by at least two directors and such insurance subsidiary's principal representative, stating that in their opinion such subsidiary will continue to satisfy the required margins following declaration of those dividends, however, there is no additional requirement for BMA approval. In addition, before reducing its total statutory capital by 15% or more (as set out in its previous year's statutory financial statements) each of the Class 3A and Class 4 Bermuda insurance subsidiaries must make application to the BMA for permission to do so; such application shall consist of an affidavit signed by at least two directors and such insurance subsidiary's principal representative stating that in their opinion the proposed reduction in capital will not cause such subsidiaries to fail to meet its relevant margins, and such other information as the BMA may require. The Insurance Act permits each of the insurance subsidiaries to declare or pay any dividends during any financial year so long as it does not cause the insurance subsidiary to fail to meet its relevant margins subject to the restrictions set out herein and other than in respect of IPCRe. The Class 3 insurers, before reducing by 15% or more of its total statutory capital, as set out in its previous year's financial statements, shall apply to the BMA for its approval and shall provide such information as the BMA may require. The Company's primary restrictions on net assets of insurance subsidiaries consist of regulatory requirements placed upon the regulated insurance subsidiaries to hold minimum amounts of total statutory capital and surplus and other than the restriction on IPCRe noted above, there were no other material restrictions on net assets in place as of December 31, 2014.
	The Company's principal operating subsidiary in Bermuda, Validus Reinsurance Ltd., maintains a branch office in Singapore. As the branch office is not considered a separate entity for regulatory purposes, the required and actual statutory capital and surplus amount includes amounts, as set out above, related to the applicable branch office. The branch office is subject to additional minimum capital or asset requirements in their country of domicile. At December 31, 2014 and 2013, the actual capital and assets for the branch exceeded the relevant local regulatory requirements.
	(b)	United Kingdom
	As disclosed in Note 22 “Commitments and contingencies (d) Funds at Lloyd’s,” Syndicate 1183 and Talbot 2002 Underwriting Capital Ltd (“T02”) are subject to regulation by the Council of Lloyd’s. Syndicate 1183 and T02 are also subject to regulation by the U.K. Financial Conduct Authority (“FCA”) and Prudential Regulation Authority (“PRA”) under the Financial Services and Market Act 2000.
	T02 is a corporate member of Lloyd’s. As a corporate member of Lloyd’s, T02 is bound by the rules of the Society of Lloyd’s, which are prescribed by Bye-laws and Requirements made by the Council of Lloyd’s under powers conferred by the Lloyd’s Act 1982. These rules (among other matters) prescribe T02’s membership subscription, the level of its contribution to the Lloyd’s central fund and the assets it must deposit with Lloyd’s in support of its underwriting. The Council of Lloyd’s has broad power to sanction breaches of its rules, including the power to restrict or prohibit a member’s participation on Lloyd’s syndicates. The capital required to support a Syndicate’s underwriting capacity, or “Funds at Lloyd’s”, is assessed annually and is determined by Lloyd’s in accordance with the rules of the Society of Lloyd’s. The capital to support the underwriting of Syndicate 1183 is provided in the form of a letter of credit and funds held at Lloyd’s. The amount provided as Funds at Lloyd’s is not available for distribution to the Company for the payment of dividends.
	Each year, during the second quarter, the corporate member applies to Lloyd’s to release accumulated funds, whether syndicate profits, interest on Funds at Lloyd’s or other which are in excess of the agreed Funds at Lloyd’s amount. At December 31, 2014 and 2013, the actual capital and assets exceeded the relevant local regulatory requirements. The release for the year ended December 31, 2014 enabled a dividend payment of $100,000 (2013: $190,000) to the Company. For further details on Funds at Lloyd's refer to Note 22 (d) "Commitments and contingencies" to the Consolidated Financial Statements.
	(c)	United States
	The Company has three U.S. based insurance subsidiaries domiciled in New Hampshire: Western World Insurance Company, Tudor Insurance Company and Stratford Insurance Company. New Hampshire insurance laws limit the amount of dividends Western World may pay to the Company in a 12-month period without the approval of the New Hampshire State Insurance Department (Insurance Department). These limitations are based on the lesser of: a maximum of 10.0% of prior year end statutory surplus as determined under statutory accounting practices or the net income, not including realized capital gains, for the 12-month period ending December 31, next preceding, but shall not include pro rata distributions of any class of the insurer's own securities. In determining whether a dividend or distribution is extraordinary, an insurer may carry forward net income from the previous two calendar years that has not already been paid out as dividends. This carry-forward shall be computed by taking the net income from the second and third preceding calendar years, not including realized capital gains, less dividends paid in the second and immediate preceding calendar years. During 2015, the maximum dividend that may be paid to the Company by Western World without obtaining prior approval is $45,209.
	The Company’s U.S. based insurance company subsidiaries are required to file financial statements prepared in accordance with accounting practices prescribed or permitted by the Insurance Department to which the insurance company subsidiaries are subject (statutory basis). Such accounting practices vary in certain respects from GAAP.
	The Company’s U.S. based insurance company subsidiaries are subject to certain Risk-Based Capital ("RBC") requirements as specified by the National Association of Insurance Commissioners. Under those requirements, the minimum amount of capital and surplus required to be maintained by a property/casualty insurance company is based on various risk factors. At December 31, 2014, the Company’s U.S. based insurance company subsidiaries met the RBC requirements.
	State insurance laws and regulations prescribe accounting practices for determining statutory net income and equity for insurance companies. In addition, state regulators may permit statutory accounting practices that differ from such prescribed practices. The Company’s insurance company subsidiaries did not use such permitted practices in 2014.
	(d)	Switzerland
	Validus Reinsurance (Switzerland) Ltd ("Validus Re Swiss") (formerly Flagstone Réassurance Suisse SA), is a société anonyme headquartered in Zurich, Switzerland as of February 1, 2014. The conduct of reinsurance business by a company headquartered in Switzerland requires a license granted by the Swiss Financial Market Supervisory Authority ("FINMA").
	Validus Re Swiss is funded by equity in the form of paid in capital by shares and in share premium. Under Swiss corporate law as modified by insurance supervisory law, a non-life insurance company is obliged to contribute to statutory legal reserves a minimum of 20% of any annual profit up to 50% of statutory capital, being paid in share capital. Validus Re Swiss has been substantially funded by share premium. Share premium can be distributed to shareholders without being subject to withholding tax. However, the distribution of any special dividend to shareholders remains subject to the approval of FINMA which has regard to the maintenance of solvency and the interests of reinsureds and creditors. At December 31, 2014 and 2013, the actual capital and assets exceeded the relevant local regulatory requirements.

Subsequent_events

Subsequent events	12 Months Ended
	Dec. 31, 2014
Subsequent Events [Abstract]
Subsequent events	Subsequent events
	(a)	Quarterly dividend
	On February 3, 2015, the Company announced a quarterly cash dividend of $0.32 per common share and $0.32 per common share equivalent for which each outstanding warrant is exercisable, payable on March 31, 2015 to holders of record as of March 13, 2015.
	(b)	Share repurchase authorization
	On February 3, 2015, the Board of Directors of the Company announced an increase in the Company's common share repurchase authorization to $750,000. This amount is in addition to the $2,274,401 of common shares repurchased by the Company through February 3, 2015 under its previously authorized share repurchase programs. The Company expects the repurchases to be made from time to time in the open market or in privately negotiated transactions. The timing, form and amount of the share repurchases under the program will depend on a variety of factors, including market conditions, the Company's capital position relative to internal and rating agency targets, legal requirements and other factors. The repurchase program may be modified, extended or terminated by the Board at any time.

Condensed_unaudited_quarterly_

Condensed unaudited quarterly financial information	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Condensed unaudited quarterly financial information	Condensed unaudited quarterly financial data
		Quarters Ended
		December 31, 2014			September 30, 2014			June 30,			March 31,
								2014			2014
		(unaudited)			(unaudited)			(unaudited)			(unaudited)
	Underwriting income
	Gross premiums written	$	336,647		$	358,974		$	655,674		$	1,011,991
	Reinsurance premiums ceded	(33,623		)	(30,137		)	(50,565		)	(194,908		)
	Net premiums written	303,024			328,837			605,109			817,083
	Change in unearned premiums	255,724			165,859			(139,106		)	(334,126		)
	Net premiums earned	558,748			494,696			466,003			482,957
	Underwriting deductions
	Losses and loss expenses	226,508			224,125			158,745			162,671
	Policy acquisition costs	89,550			86,404			78,953			85,649
	General and administrative expenses	98,186			83,319			73,842			74,445
	Share compensation expenses	8,821			8,764			8,341			7,147
	Total underwriting deductions	423,065			402,612			319,881			329,912
	Underwriting income	$	135,683		$	92,084		$	146,122		$	153,045
	Net investment income	30,167			25,261			21,286			23,362
	Other insurance related income	5,524			3,610			4,811			8,037
	Finance expenses	(16,474		)	(15,354		)	(16,126		)	(15,900		)
	Operating income before taxes, (income) from operating affiliates and (income) loss attributable to operating affiliate investors	$	154,900		$	105,601		$	156,093		$	168,544
	Tax benefit (expense)	243			953			(1,391		)	40
	Income from operating affiliates	4,143			3,761			4,892			4,927
	(Income) attributable to operating affiliate investors	(26,566		)	(25,807		)	(25,316		)	(31,710		)
	Net operating income	$	132,720		$	84,508		$	134,278		$	141,801
	Net realized gains on investments	6,902			4,595			7,858			3,740
	Net unrealized (losses) gains on investments	(74,119		)	(84,974		)	45,427			55,693
	Income from investment affiliate	530			1,754			779			5,348
	Foreign exchange gains (losses)	4,131			(11,441		)	3,158			(6,478		)
	Other (loss) income	(770		)	(7,690		)	424			5,793
	Transaction expenses	(4,695		)	(149		)	(3,252		)	—
	Net income (loss)	$	64,699		$	(13,397	)	$	188,672		$	205,897
	Net loss (income) attributable to noncontrolling interest	61,209			53,069			(35,305		)	(43,509		)
	Net income available to Validus	$	125,908		$	39,672		$	153,367		$	162,388
	Earnings per share
	Weighted average number of common shares and common share equivalents outstanding
	Basic	86,421,127			90,593,329			90,952,523			93,451,999
	Diluted	90,948,156			91,939,610			95,276,836			97,799,519
	Basic earnings per share available to common shareholders	$	1.44		$	0.42		$	1.67		$	1.72
	Earnings per diluted share available to common shareholders	$	1.38		$	0.41		$	1.61		$	1.66
	Selected ratios:
	Losses and loss expenses	40.5		%	45.3		%	34.1		%	33.7		%
	Expense ratio	35.2		%	36.1		%	34.5		%	34.6		%
	Combined ratio	75.7		%	81.4		%	68.6		%	68.3		%
		Quarters Ended
		December 31,			September 30,			June 30,			March 31,
		2013			2013			2013			2013
		(unaudited)			(unaudited)			(unaudited)			(unaudited)
	Underwriting income
	Gross premiums written	$	237,273		$	356,760		$	702,313		$	1,104,760
	Reinsurance premiums ceded	(24,558		)	(39,415		)	(121,396		)	(187,216		)
	Net premiums written	212,715			317,345			580,917			917,544
	Change in unearned premiums	279,523			213,943			(33,459		)	(386,483		)
	Net premiums earned	492,238			531,288			547,458			531,061
	Underwriting deductions
	Losses and loss expenses	206,152			177,965			265,044			144,771
	Policy acquisition costs	84,647			94,900			87,152			93,611
	General and administrative expenses	82,930			81,089			70,967			80,279
	Share compensation expenses	8,147			10,527			6,638			2,318
	Total underwriting deductions	381,876			364,481			429,801			320,979
	Underwriting income	$	110,362		$	166,807		$	117,657		$	210,082
	Net investment income	24,204			20,009			26,210			25,649
	Other insurance related income	7,743			943			5,512			4,922
Finance expenses	(16,925		)	(15,317		)	(17,566		)	(14,369		)
Operating income before taxes, income from operating affiliates and (income) attributable to operating affiliate investors	$	125,384		$	172,442		$	131,813		$	226,284
Tax (expense) benefit	(603		)	(5		)	(93		)	318
Income from operating affiliates	5,510			1,463			3,793			3,523
(Income) attributable to operating affiliate investors (a)	(26,607		)	(11,815		)	(20,264		)	(10,077		)
Net operating income	$	103,684		$	162,085		$	115,249		$	220,048
Net realized gains (losses) on investments	4,448			(6,320		)	3,409			1,721
Net unrealized gains (losses) on investments	20,137			69,967			(141,348		)	(7,237		)
Income from investment affiliate	516			1,044			1,753			1,477
Foreign exchange (losses) gains	(2,230		)	6,036			(8,223		)	6,922
Other loss	(3,697		)	(3,749		)	(1,094		)	(2,237		)
Net income (loss)	$	122,858		$	229,063		$	(30,254	)	$	220,694
Net (income) loss (available) attributable to noncontrolling interest	(27,526		)	(45,694		)	60,976			2,549
Net income available to Validus	$	95,332		$	183,369		$	30,722		$	223,243
Earnings per share
Weighted average number of common shares and common share equivalents outstanding
Basic	98,454,907			99,834,563			103,133,188			107,386,438
Diluted	102,928,482			103,613,766			104,734,643			110,052,999
Basic earnings per share available to common shareholders	$	0.95		$	1.82		$	0.28		$	1.94
Earnings per diluted share available to common shareholders	$	0.93		$	1.77		$	0.28		$	1.9
Selected Ratios:
Losses and loss expenses	41.9		%	33.5		%	48.4		%	27.3		%
Expense ratio	35.7		%	35.1		%	30.1		%	33.2		%
Combined ratio	77.6		%	68.6		%	78.5		%	60.5		%
(a)	This amount had been shown within finance expenses for each of the three months ended March 31, June 30 and September 30, 2013.
	Quarters Ended
	December 31, 2012			September 30, 2012			June 30,			March 31,
							2012			2012
	(unaudited)			(unaudited)			(unaudited)			(unaudited)
Underwriting income
Gross premiums written	$	311,847		$	390,215		$	627,089		$	837,289
Reinsurance premiums ceded	(35,659		)	(45,743		)	(119,052		)	(107,052		)
Net premiums written	276,188			344,472			508,037			730,237
Change in unearned premiums	223,098			130,632			(60,410		)	(279,038		)
Net premiums earned	499,286			475,104			447,627			451,199
Underwriting deductions
Losses and loss expenses	458,310			155,455			153,692			231,989
Policy acquisition costs	81,814			98,623			76,129			78,132
General and administrative expenses	65,095			70,547			61,635			66,375
Share compensation expenses	7,126			7,345			6,800			5,438
Total underwriting deductions	612,345			331,970			298,256			381,934
Underwriting (loss) income	$	(113,059	)	$	143,134		$	149,371		$	69,265
Net investment income	28,802			25,489			25,885			27,760
Other insurance related income	144			7,324			6,606			8,237
Finance expenses	(14,510		)	(9,362		)	(13,706		)	(16,279		)
Operating (loss) income before taxes and (loss) income from operating affiliates	$	(98,623	)	$	166,585		$	168,156		$	88,983
Tax expense	(615		)	(1,343		)	(404		)	(139		)
(Loss) income from operating affiliates	$	(614	)	$	6,235		$	3,592		$	3,367
Net operating (loss) income	$	(99,852	)	$	171,477		$	171,344		$	92,211
Gain on bargain purchase, net of expenses (a)	21,485			(3,784		)	—			—
Net realized (losses) gains on investments	(4,516		)	9,063			6,154			7,532
Net unrealized (losses) gains on investments	(35,857		)	86,345			(53,574		)	20,671
Loss from investment affiliate	(406		)	(160		)	(398		)	—
Foreign exchange gains (losses)	1,181			1,103			(652		)	3,166
Other income (loss)	43			—			(612		)	654
Net (loss) income	$	(117,922	)	$	264,044		$	122,262		$	124,234
Net loss (income) attributable (available) to noncontrolling interest	27,206			(56,746		)	45,360			—
Net (loss) income (attributable) available to Validus	$	(90,716	)	$	207,298		$	167,622		$	124,234
Earnings per share
Weighted average number of common shares and common share equivalents outstanding
Basic	97,688,338			93,368,775			98,254,186			99,425,140
Diluted	97,688,338			98,236,490			103,667,967			105,096,090
Basic (loss) earnings per share (attributable) available to common shareholders	$	(0.94	)	$	2.2		$	1.69		$	1.23
(Loss) earnings per diluted share (attributable) available to common shareholders	$	(0.94	)	$	2.11		$	1.62		$	1.18
Selected Ratios:
Losses and loss expenses	91.8		%	32.7		%	34.3		%	51.4		%
Expense ratio	30.9		%	37.2		%	32.3		%	33.2		%
Combined ratio	122.7		%	69.9		%	66.6		%	84.6		%
(a)	The gain on bargain purchase, net of expenses, arose from the acquisition of Flagstone Reinsurance Holdings S.A. on November 30, 2012 and is net of transaction related expenses which included legal, financial advisory, audit related services and termination expenses.

Condensed_consolidating_financ

Condensed consolidating financial information	12 Months Ended
	Dec. 31, 2014
Condensed Consolidating Financial Information [Abstract]
Condensed consolidated parent company and guarantor financial statements	Condensed consolidating financial information
	The following tables present condensed consolidating balance sheets as at December 31, 2014 and 2013, condensed consolidating statements of comprehensive income and condensed consolidating statements of cash flows for the years ended December 31, 2014, 2013 and 2012, respectively, for Validus Holdings, Ltd. (the “Parent Guarantor”), Validus Holdings (UK) plc (the “Subsidiary Issuer”) and the non-guarantor subsidiaries of Validus Holdings, Ltd. The Subsidiary Issuer is a wholly-owned subsidiary of the Parent Guarantor. Investments in subsidiaries are accounted for under the equity method for purposes of the supplemental consolidating presentation and earnings of subsidiaries are reflected in the investment accounts and earnings. The Subsidiary Issuer is only allowed to issue senior notes that are fully and unconditionally guaranteed by the Parent Guarantor.
	Condensed Consolidating Balance Sheet	Validus Holdings, Ltd.			Validus Holdings			Other			Consolidating Adjustments (b)			Validus Holdings, Ltd.
	As at December 31, 2014	(Parent Guarantor)			(UK) plc			Validus Holdings, Ltd.						Consolidated
					(Subsidiary Issuer)			Subsidiaries
								(Non-guarantor Subsidiaries) (a)
	Assets
	Fixed maturities, at fair value	$	—		$	—		$	5,592,931		$	(60,200	)	$	5,532,731
	Short-term investments, at fair value	—			—			1,051,074			—			$	1,051,074
	Other investments, at fair value	—			—			881,123			(68,112		)	$	813,011
	Cash and cash equivalents	29,798			81			547,361			—			$	577,240
	Restricted cash	—			—			173,003			—			173,003
	Total investments and cash	29,798			81			8,245,492			(128,312		)	8,147,059
	Investment in affiliates	—			—			261,483			—			261,483
	Investment in subsidiaries on an equity basis	4,140,770			656,738			—			(4,797,508		)	—
	Premiums receivable	—			—			707,647			—			707,647
	Deferred acquisition costs	—			—			161,295			—			161,295
	Prepaid reinsurance premiums	—			—			81,983			—			81,983
	Securities lending collateral	—			—			470			—			470
	Loss reserves recoverable	—			—			377,466			—			377,466
	Paid losses recoverable	—			—			38,078			—			38,078
	Deferred tax asset	—			—			23,821			—			23,821
	Intangible assets	—			—			126,924			—			126,924
	Goodwill	—			—			195,897			—			195,897
	Intercompany receivable	41,078			—			20			(41,098		)	—
	Other assets	3,239			—			186,259			—			189,498
	Total assets	$	4,214,885		$	656,819		$	10,406,835		$	(4,966,918	)	$	10,311,621
	Liabilities
	Reserve for losses and loss expenses	$	—		$	—		$	3,234,394		$	—		$	3,234,394
	Unearned premiums	—			—			990,564			—			990,564
	Reinsurance balances payable	—			—			127,128			—			127,128
	Securities lending payable	—			—			936			—			936
	Deferred tax liability	—			—			5,541			—			5,541
	Net payable for investments purchased	—			—			50,256			—			50,256
	Accounts payable and accrued expenses	29,621			96			288,528			—			318,245
	Intercompany payable	—			20			41,078			(41,098		)	—
	Notes payable to operating affiliates	—			—			671,465			—			671,465
	Senior notes payable	247,306			—			—			—			247,306
	Debentures payable	350,000			—			249,477			(60,200		)	539,277
	Total liabilities	$	626,927		$	116		$	5,659,367		$	(101,298	)	$	6,185,112
	Redeemable noncontrolling interest	—			—			79,956			—			79,956
	Total shareholders' equity available to Validus	3,587,958			656,703			4,208,917			(4,865,620		)	3,587,958
	Noncontrolling interest	—			—			458,595			—			458,595
	Total liabilities, noncontrolling interests and shareholders' equity	$	4,214,885		$	656,819		$	10,406,835		$	(4,966,918	)	$	10,311,621
	(a)	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.
	(b)	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
	Condensed Consolidating Balance Sheet	Validus Holdings, Ltd.			Validus Holdings			Other			Consolidating Adjustments (b)			Validus Holdings, Ltd.
	As at December 31, 2013	(Parent Guarantor)			(UK) plc			Validus Holdings, Ltd.						Consolidated
					(Subsidiary Issuer)			Subsidiaries
								(Non-guarantor Subsidiaries) (a)
	Assets
	Fixed maturities, at fair value	$	—		$	—		$	5,602,458		$	(60,200	)	$	5,542,258
	Short-term investments, at fair value	—			—			787,714			—			787,714
	Other investments, at fair value	—			—			770,116			(66,030		)	704,086
	Cash and cash equivalents	20,385			—			713,763			—			734,148
	Restricted cash	—			—			200,492			—			200,492
	Total investments and cash	$	20,385		$	—		$	8,074,543		$	(126,230	)	$	7,968,698
	Investments in affiliates	—			—			141,243			—			141,243
	Investment in subsidiaries on an equity basis	4,273,592			8,479			—			(4,282,071		)	—
	Premiums receivable	—			—			697,233			—			697,233
	Deferred acquisition costs	—			—			134,269			—			134,269
	Prepaid reinsurance premiums	—			—			103,251			—			103,251
	Securities lending collateral	—			—			3,392			—			3,392
	Loss reserves recoverable	—			—			370,154			—			370,154
Paid losses recoverable	—			—			80,080			—			80,080
Intangible assets	—			—			106,407			—			106,407
Goodwill	—			—			20,393			—			20,393
Intercompany receivable	29,048			—			100			(29,148		)	—
Other assets	3,767			—			217,545			—			221,312
Total assets	$	4,326,792		$	8,479		$	9,948,610		$	(4,437,449	)	$	9,846,432
Liabilities
Reserve for losses and loss expenses	$	—		$	—		$	3,030,399		$	—		$	3,030,399
Unearned premiums	—			—			824,496			—			824,496
Reinsurance balances payable	—			—			154,874			—			154,874
Securities lending payable	—			—			3,858			—			3,858
Deferred tax liability	—			—			19,086			—			19,086
Net payable for investments purchased	—			—			19,383			—			19,383
Accounts payable and accrued expenses	25,500			—			252,687			—			278,187
Intercompany payable	—			100			29,048			(29,148		)	—
Notes payable to operating affiliates	—			—			439,272			—			439,272
Senior notes payable	247,198			—			—			—			247,198
Debentures payable	350,000			—			251,616			(60,200		)	541,416
Total liabilities	$	622,698		$	100		$	5,024,719		$	(89,348	)	$	5,558,169
Redeemable noncontrolling interest	—			—			86,512			—			86,512
Total shareholders' equity available to Validus	3,704,094			8,379			4,339,722			(4,348,101		)	3,704,094
Noncontrolling interest	—			—			497,657			—			497,657
Total liabilities, noncontrolling interest and shareholders' equity	$	4,326,792		$	8,479		$	9,948,610		$	(4,437,449	)	$	9,846,432
(a)	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.
(b)	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
Condensed Consolidating	Validus Holdings, Ltd.			Validus Holdings			Other			Consolidating Adjustments (b)			Validus Holdings, Ltd.
Statement of Comprehensive Income	(Parent Guarantor)			(UK) plc			Validus Holdings, Ltd.						Consolidated
For the Year Ended December 31, 2014				(Subsidiary Issuer)			Subsidiaries
							(Non-guarantor Subsidiaries) (a)
Revenues
Net premiums earned	$	—		$	—		$	2,002,404		$	—		$	2,002,404
Net investment income	14			—			103,972			(3,910		)	100,076
Net realized gains on investments	—			—			23,095			—			23,095
Change in net unrealized losses on investments	—			—			(55,891		)	(2,082		)	(57,973		)
Income from investment affiliate	—			—			8,411			—			8,411
Other insurance related income and other income	—			—			86,906			(67,167		)	19,739
Foreign exchange gains (losses)	648			1			(11,279		)	—			(10,630		)
Total revenues	$	662		$	1		$	2,157,618		$	(73,159	)	$	2,085,122
Expenses
Losses and loss expenses	—			—			772,049			—			772,049
Policy acquisition costs	—			—			340,556			—			340,556
General and administrative expenses	86,108			117			310,734			(67,167		)	329,792
Share compensation expenses	6,424			—			26,649			—			33,073
Finance expenses	47,689			—			18,109			(1,944		)	63,854
Transaction expenses	—			—			8,096			—			8,096
Total expenses	$	140,221		$	117		$	1,476,193		$	(69,111	)	$	1,547,420
(Loss) income before taxes, income from operating affiliates, (income) attributable to operating affiliate investors and equity in net earnings of subsidiaries	(139,559		)	(116		)	681,425			(4,048		)	537,702
Tax expense	—			—			(155		)	—			(155		)
Income from operating affiliates	—			—			17,723			—			17,723
(Income) attributable to operating affiliate investors	—			—			(109,399		)	—			(109,399		)
Equity in net earnings of subsidiaries	620,894			1,940			—			(622,834		)	—
Net income (loss)	$	481,335		$	1,824		$	589,594		$	(626,882	)	$	445,871
Net loss attributable to noncontrolling interest	—			—			35,464			—			35,464
Net income (loss) available (attributable) to Validus	$	481,335		$	1,824		$	625,058		$	(626,882	)	$	481,335
Other comprehensive (loss) income	(7,939		)	—			(7,711		)	7,711			(7,939		)
Comprehensive income (loss) available (attributable) to Validus	$	473,396		$	1,824		$	617,347		$	(619,171	)	$	473,396
(a)	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.
(b)	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
Condensed Consolidating	Validus Holdings, Ltd.			Validus Holdings			Other			Consolidating Adjustments (b)			Validus Holdings, Ltd.
Statement of Comprehensive Income	(Parent Guarantor)			(UK) plc			Validus Holdings, Ltd.						Consolidated
For the Year Ended December 31, 2013				(Subsidiary Issuer)			Subsidiaries
							(Non-guarantor Subsidiaries) (a)
Revenues
Net premiums earned	$	—		$	—		$	2,102,045		$	—		$	2,102,045
Net investment income	14			—			103,272			(7,214		)	96,072
Net realized gains on investments	—			—			3,258			—			3,258
Change in net unrealized losses on investments	—			—			(49,599		)	(8,882		)	(58,481		)
Income from investment affiliate	—			—			4,790			—			4,790
Other insurance related income and other income	36			—			75,425			(67,118		)	8,343
Foreign exchange (losses) gains	(382		)	—			2,887			—			2,505
Total revenues	$	(332	)	$	—		$	2,242,078		$	(83,214	)	$	2,158,532
Expenses
Losses and loss expenses	—			—			793,932			—			793,932
Policy acquisition costs	—			—			360,310			—			360,310
General and administrative expenses	84,143			—			298,240			(67,118		)	315,265
Share compensation expenses	6,329			—			21,301			—			27,630
Finance expenses	45,868			—			20,278			(1,969		)	64,177
Total expenses	$	136,340		$	—		$	1,494,061		$	(69,087	)	$	1,561,314
(Loss) income before taxes, income from operating affiliates, (income) attributable to operating affiliate investors and equity in net earnings (losses) of subsidiaries	(136,672		)	—			748,017			(14,127		)	597,218
Tax expense	—			—			(383		)	—			(383		)
Income from operating affiliates	—			—			14,289			—			14,289
(Income) attributable to operating affiliate investors	—			—			(68,763		)	—			(68,763		)
Equity in net earnings (losses) of subsidiaries	669,338			(5,938		)	—			(663,400		)	—
Net income (loss)	$	532,666		$	(5,938	)	$	693,160		$	(677,527	)	$	542,361
Net income attributable to noncontrolling interest	—			—			(9,695		)	—			(9,695		)
Net income (loss) available (attributable) to Validus	$	532,666		$	(5,938	)	$	683,465		$	(677,527	)	$	532,666
Other comprehensive (loss) income	(1,954		)	—			(1,954		)	1,954			(1,954		)
Comprehensive income (loss) available (attributable) to Validus	$	530,712		$	(5,938	)	$	681,511		$	(675,573	)	$	530,712
(a)	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.
(b)	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
Condensed Consolidating	Validus Holdings, Ltd.			Validus Holdings			Other			Consolidating Adjustments (b)			Validus Holdings, Ltd.
Statement of Comprehensive Income	(Parent Guarantor)			(UK) plc			Validus Holdings, Ltd.						Consolidated
For the Year Ended December 31, 2012				(Subsidiary Issuer)			Subsidiaries
							(Non-guarantor Subsidiaries) (a)
Revenue
Net premiums earned	$	—		$	—		$	1,873,216		$	—		$	1,873,216
Gain on bargain purchase, net of expenses	—			—			17,701			—			17,701
Net investment income	3			—			113,375			(5,442		)	107,936
Net realized gains on investments	—			—			18,233			—			18,233
Change in net unrealized gains on investments	—			—			17,585			—			17,585
Loss from investment affiliate	—			—			(964		)	—			(964		)
Other insurance related income and other income	—			—			37,022			(14,626		)	22,396
Foreign exchange (losses) gains	(469		)	—			5,267			—			4,798
Total revenue	$	(466	)	$	—		$	2,081,435		$	(20,068	)	$	2,060,901
Expenses
Losses and loss expenses	—			—			999,446			—			999,446
Policy acquisition costs	—			—			334,698			—			334,698
General and administrative expenses	66,576			—			211,702			(14,626		)	263,652
Share compensation expenses	8,503			—			18,206			—			26,709
Finance expenses	45,203			—			12,186			(3,532		)	53,857
Total expenses	$	120,282		$	—		$	1,576,238		$	(18,158	)	$	1,678,362
(Loss) income before taxes, income from operating affiliates and equity in net earnings (losses) of subsidiaries	(120,748		)	—			505,197			(1,910		)	382,539
Tax expense	—			—			(2,501		)	—			(2,501		)
Income from operating affiliates	—			—			12,580			—			12,580
Equity in net earnings (losses) of subsidiaries	529,186			(1,306		)	—			(527,880		)	—
Net income (loss)	$	408,438		$	(1,306	)	$	515,276		$	(529,790	)	$	392,618
Net loss attributable to noncontrolling interest	—			—			15,820			—			15,820
Net income (loss) available (attributable) to Validus	$	408,438		$	(1,306	)	$	531,096		$	(529,790	)	$	408,438
Other comprehensive income (loss)	3,648			—			3,648			(3,648		)	3,648
Comprehensive income (loss) available (attributable) to Validus	$	412,086		$	(1,306	)	$	534,744		$	(533,438	)	$	412,086
(a)	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.
(b)	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
Condensed Consolidating Statement of Cash Flows	Validus Holdings, Ltd.			Validus Holdings			Other			Consolidating Adjustments (b)			Validus Holdings, Ltd.
For the Year Ended December 31, 2014	(Parent Guarantor)			(UK) plc			Validus Holdings, Ltd.						Consolidated
				(Subsidiary Issuer)			Subsidiaries
							(Non-guarantor Subsidiaries) (a)
Net cash (used in) provided by operating activities	$	(41,905	)	$	81		$	383,605		$	(100,000	)	$	241,781
Cash flows provided by (used in) investing activities
Proceeds on sales of investments	—			—			4,756,555			—			4,756,555
Proceeds on maturities of investments	—			—			554,619			—			554,619
Purchases of fixed maturities	—			—			(4,379,314		)	—			(4,379,314		)
Purchases of short-term investments, net	—			—			(121,264		)	—			(121,264		)
Purchases of other investments	—			—			(119,815		)	—			(119,815		)
Decrease in securities lending collateral	—			—			2,922			—			2,922
Investment in operating affiliates	—			—			(37,600		)	—			(37,600		)
Redemption from operating affiliates	—			—			77,544			—			77,544
Investment in investment affiliates	—			—			(12,468		)	—			(12,468		)
Decrease in restricted cash	—			—			27,489			—			27,489
Proceeds on sale of subsidiary, net of cash	—			—			16,459			—			16,459
Purchase of subsidiary, net of cash acquired	—			—			(643,545		)	—			(643,545		)
Return of capital from subsidiaries	673,966			—			—			(673,966		)	—
Investment in subsidiaries	—			(240,000		)	(240,000		)	480,000			—
Net cash provided by (used in) investing activities	673,966			(240,000		)	(118,418		)	(193,966		)	121,582
Cash flows provided by (used in) financing activities
Proceeds on issuance of notes payable to operating affiliates	—			—			680,027			—			680,027
Repayments on notes payable to operating affiliates	—			—			(617,068		)	—			(617,068		)
Issuance of common shares, net	5,347			—			—			—			5,347
Purchases of common shares under share repurchase program	(510,952		)	—			—			—			(510,952		)
Dividends paid	(117,043		)	—			(100,000		)	100,000			(117,043		)
Decrease in securities lending payable	—			—			(2,922		)	—			(2,922		)
Third party investment in redeemable noncontrolling interest	—			—			68,200			—			68,200
Third party redemption of redeemable noncontrolling interest	—			—			(10,496		)	—			(10,496		)
Third party subscriptions received in advance	—			—			15,400			—			15,400
Return of capital to parent	—			—			(673,966		)	673,966			—
Capital contribution from parent	—			240,000			240,000			(480,000		)	—
Net cash (used in) provided by financing activities	(622,648		)	240,000			(400,825		)	293,966			(489,507		)
Effect of foreign currency rate changes on cash and cash equivalents	—			—			(30,764		)	—			(30,764		)
Net increase (decrease) in cash	9,413			81			(166,402		)	—			(156,908		)
Cash and cash equivalents, beginning of year	20,385			—			713,763			—			734,148
Cash and cash equivalents, end of year	$	29,798		$	81		$	547,361		$	—		$	577,240
(a)	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.
(b)	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
Condensed Consolidating Statement of Cash Flows	Validus Holdings, Ltd.			Validus Holdings			Other			Consolidating Adjustments (b)			Validus Holdings, Ltd.
For the Year Ended December 31, 2013	(Parent Guarantor)			(UK) plc			Validus Holdings, Ltd.						Consolidated
				(Subsidiary Issuer)			Subsidiaries
							(Non-guarantor Subsidiaries) (a)
Net cash provided by (used in) operating activities	$	873,083		$	—		$	401,191		$	(1,009,000	)	$	265,274
Cash flows provided by (used in) investing activities
Proceeds on sales of investments	—			—			4,370,548			—			4,370,548
Proceeds on maturities of investments	—			—			490,459			—			490,459
Purchases of fixed maturities	—			—			(5,392,728		)	—			(5,392,728		)
Sales of short-term investments, net	—			—			353,353			—			353,353
Purchases of other investments	—			—			(38,492		)	—			(38,492		)
Increase in securities lending collateral	—			—			(3,167		)	—			(3,167		)
Investment in operating affiliates	—			—			(22,000		)	—			(22,000		)
Redemption from operating affiliates	—			—			86,657			—			86,657
Investment in investment affiliates	—			—			(14,492		)	—			(14,492		)
Increase in restricted cash	—			—			(172,962		)	—			(172,962		)
Proceeds on sale of subsidiary, net of cash	—			—			21,388			—			21,388
Net cash used in investing activities	—			—			(321,436		)	—			(321,436		)
Cash flows provided by (used in) financing activities
Proceeds on issuance of notes payable to operating affiliates	—			—			442,412			—			442,412
Repayments on notes payable to operating affiliates	—			—			(3,553		)	—			(3,553		)
Issuance of common shares, net	1,211			—			—			—			1,211
Purchases of common shares under share repurchase program	(513,504		)	—			—			—			(513,504		)
Dividends paid	(360,071		)	—			(1,009,000		)	1,009,000			(360,071		)
Increase in securities lending payable	—			—			3,167			—			3,167
Third party investment in redeemable noncontrolling interest	—			—			92,190			—			92,190
Third party redemption of redeemable noncontrolling interest	—			—			(19,400		)	—			(19,400		)
Investment in third party noncontrolling interest	—			—			58,500			—			58,500
Third party subscriptions received in advance	—			—			35,000			—			35,000
Net cash (used in) provided by financing activities	(872,364		)	—			(400,684		)	1,009,000			(264,048		)
Effect of foreign currency rate changes on cash and cash equivalents	—			—			(6,364		)	—			(6,364		)
Net increase (decrease) in cash	719			—			(327,293		)	—			(326,574		)
Cash and cash equivalents, beginning of year	19,666			—			1,041,056			—			1,060,722
Cash and cash equivalents, end of year	$	20,385		$	—		$	713,763		$	—		$	734,148
(a)	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.
(b)	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
Condensed Consolidating Statement of Cash Flows	Validus Holdings, Ltd.			Validus Holdings			Other			Consolidating Adjustments (b)			Validus Holdings, Ltd.
For the Year Ended December 31, 2012	(Parent Guarantor)			(UK) plc			Validus Holdings, Ltd.						Consolidated
				(Subsidiary Issuer)			Subsidiaries
							(Non-guarantor Subsidiaries) (a)
Net cash provided by (used in) operating activities	$	548,288		$	—		$	728,877		$	(734,000	)	$	543,165
Cash flows provided by (used in) investing activities
Proceeds on sales of investments	—			—			3,393,740			—			3,393,740
Proceeds on maturities of investments	—			—			548,226			—			548,226
Purchases of fixed maturities	—			—			(3,726,611		)	—			(3,726,611		)
Sales of short-term investments, net	—			—			56,502			—			56,502
Purchases of other investments	—			—			(491,210		)	—			(491,210		)
Decrease in securities lending collateral	—			—			7,771			—			7,771
Investment in operating affiliates	—			—			(91,500		)	—			(91,500		)
Investment in investment affiliates	—			—			(12,835		)	—			(12,835		)
Increase in restricted cash	—			—			(3,493		)	—			(3,493		)
Purchase of subsidiary, net of cash acquired	—			—			17,196			—			17,196
Investment in subsidiaries	(166,582		)	—			—			166,582			—
Net cash (used in) provided by investing activities	(166,582		)	—			(302,214		)	166,582			(302,214		)
Cash flows provided by (used in) financing activities
Issuance of common shares, net	3,015			—			—			—			3,015
Purchases of common shares under share repurchase program	(259,962		)	—			—			—			(259,962		)
Dividends paid	(110,037		)	—			(734,000		)	734,000			(110,037		)
Decrease in securities lending payable	—			—			(7,771		)	—			(7,771		)
Investment in third party noncontrolling interest	—			—			450,100			—			450,100
Third party subscriptions received in advance	—			—			19,400			—			19,400
Capital contribution from parent	—			—			166,582			(166,582		)	—
Net cash (used in) provided by financing activities	(366,984		)	—			(105,689		)	567,418			94,745
Effect of foreign currency rate changes on cash and cash equivalents	—			—			17,540			—			17,540
Net increase in cash	14,722			—			338,514			—			353,236
Cash and cash equivalents, beginning of year	4,944			—			702,542			—			707,486
Cash and cash equivalents, end of year	$	19,666		$	—		$	1,041,056		$	—		$	1,060,722
(a)	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.
(b)	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.

Significant_accounting_policie1

Significant accounting policies (Policies)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Basis of preparation	These Consolidated Financial Statements include Validus Holdings, Ltd. and its wholly and majority owned subsidiaries and have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Certain amounts with respect to cash and cash equivalents have been revised to correct certain prior period comparatives in these Consolidated Financial Statements.
	All significant intercompany accounts and transactions have been eliminated.
Use of estimates	The preparation of these financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. While management believes that the amounts included in the Consolidated Financial Statements reflect its best estimates and assumptions, actual results could differ from those estimates. The Company’s principal estimates include:
	•reserve for losses and loss expenses;
	•premium estimates for business written on a line slip or proportional basis;
	•the valuation of goodwill and intangible assets;
	•reinsurance recoverable balances including the provision for uncollectible amounts; and
	•investment valuation of financial assets.
	The term “ASC” used in these notes refers to Accounting Standard Codification issued by the United States Financial Accounting Standards Board (“FASB”).
Premiums	Insurance premiums written are recorded in accordance with the terms of underlying policies. Reinsurance premiums written are recorded at the inception of the policy and are estimated based on information received from brokers, ceding companies and reinsureds, and any subsequent differences arising on such estimates will be recorded in the periods in which they are determined. Premiums written are earned on a pro-rated basis over the term of the policy. For contracts and policies written on a losses occurring basis, the risk period is generally the same as the contract or policy terms. For contracts written on a policies attaching basis, the risk period is based on the terms of the underlying contracts and policies and is generally assumed to be 24 months. The portion of the premiums written applicable to the unexpired terms of the underlying contracts and policies in force is recorded as unearned premiums.
	Reinstatement premiums are recorded at the time a loss event occurs and coverage limits for the remaining life of the contract are reinstated under predefined contract terms. The accrual of reinstatement premiums is based on our estimate of losses and loss expenses, which reflects management’s judgment, as described in Note 3(c) "Reserve for losses and loss expenses" below.
Policy acquisition costs	Policy acquisition costs are costs that vary with, and are directly related to, the successful production of new and renewal business, and consist principally of commissions and brokerage expenses. Acquisition costs are shown net of commissions earned on reinsurance ceded. These costs are deferred and amortized over the periods in which the related premiums are earned. Deferred acquisition costs are limited to their estimated realizable value based on the related unearned premiums and anticipated claims expenses. The realizable value of the Company’s deferred acquisition costs is determined without consideration of investment income. Policy acquisition costs also include profit commissions. Profit commissions are recognized on a basis consistent with our estimate of losses and loss expenses.
Reserves for losses and loss expenses	The reserve for losses and loss expenses includes reserves for unpaid reported losses and for losses incurred but not reported (“IBNR”). The reserve for unpaid reported losses and loss expenses is established by management based on reports from brokers, ceding companies and insureds and represents the estimated ultimate cost of events or conditions that have been reported to, or specifically identified by, the Company. The reserve for incurred but not reported losses and loss expenses is established by management based on actuarially determined estimates of ultimate losses and loss expenses. Inherent in the estimate of ultimate losses and loss expenses are expected trends in claim severity and frequency and other factors which may vary significantly as claims are settled. Accordingly, ultimate losses and loss expenses may differ materially from the amounts recorded in the Consolidated Financial Statements. These estimates are reviewed regularly and, as experience develops and new information becomes known, the reserves are adjusted as necessary. Such adjustments, if any, will be recorded in earnings in the period in which they become known. Prior period development arises from changes to these estimates recognized in the current year that relate to reserves for losses and loss expenses established in previous calendar years.
Reinsurance	In the normal course of business, the Company seeks to reduce the potential amount of loss arising from claims events by reinsuring certain levels of risk assumed in various areas of exposure with other insurers or reinsurers. The accounting for reinsurance ceded depends on the method of reinsurance. If the policy is on a “losses occurring” basis, reinsurance premiums ceded are expensed (and any commissions thereon are earned) on a pro-rata basis over the period the reinsurance coverage is provided. If the policy is a “risks attaching” policy, reinsurance premiums ceded are expensed (and any commissions thereon are earned) in line with the earning of the gross premiums to which the risk attaching policy relates. Prepaid reinsurance premiums represent the portion of premiums ceded applicable to the unexpired term of policies in force. Mandatory reinstatement premiums ceded are recorded at the time the loss event occurs. Reinsurance recoverables are based on contracts in force at the time of the underlying loss event. The method for determining the reinsurance recoverable on unpaid losses and loss expenses involves the actuarial estimates of unpaid losses and loss expenses as well as a determination of the Company’s ability to cede unpaid losses and loss expenses under its reinsurance treaties. The use of different assumptions could have a material effect on the provision for uncollectible reinsurance. To the extent the creditworthiness of the Company’s reinsurers was to deteriorate due to adverse events affecting the reinsurance industry, such as a large number of major catastrophes, actual uncollectible amounts could be significantly greater than the Company’s provision. Amounts recoverable from reinsurers are estimated in a manner consistent with the underlying liabilities.
Investments	All investments are carried at fair value with interest and dividend income and realized and unrealized gains and losses included in net income for the year.
	All investment transactions are recorded on a first-in-first-out basis and realized gains and losses on the sale of investments are determined on the basis of amortized cost. Interest on fixed maturity securities is recorded in net investment income when earned and is adjusted for any amortization of premium or accretion of discount.
	For mortgage-backed securities, and any other holdings for which there is a prepayment risk, prepayment assumptions are evaluated and revised as necessary. Any adjustments required due to the resultant change in effective yields and maturities are recognized retrospectively. Prepayment fees or call premiums that are only payable to the Company when a security is called prior to its maturity, are earned when received and reflected in net investment income.
	Short-term investments primarily comprise of investments with a remaining maturity of less than one year at time of purchase and money market funds held at the Company’s investment managers. Certain short-term investments relate to funds held in trust in support of collateralized reinsurance transactions.
Other investments	The fair value of other investments is generally recorded on the basis of the net asset valuation criteria established by the managers of the investments, normally based upon the governing documents of such investments. In addition, due to a lag in reporting, some of the fund managers, fund administrators, or both, are unable to provide final fund valuations as of the Company’s reporting date. In these circumstances, the Company estimates the fair value of these funds by starting with the prior month’s or prior quarter's fund valuation, adjusting these valuations for capital calls, redemptions or distributions and the impact of changes in foreign currency exchange rates, and then estimating the return for the current period. In circumstances in which the Company estimates the return for the current period, it uses all credible information available. This includes utilizing preliminary estimates reported by its fund managers, obtaining the valuation of underlying portfolio investments where such underlying investments are publicly traded and therefore have a readily observable price, using information that is available to the Company with respect to the underlying investments, reviewing various indices for similar investments or asset classes, as well as estimating returns based on the results of similar types of investments for which the Company has reported results, or other valuation methods, as necessary. Actual final fund valuations may differ, perhaps materially so, from the Company’s estimates and these differences are recorded in the period they become known as a change in estimate.
Fair value of financial instruments	Fair value is defined as the price received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date reflecting the highest and best use valuation concepts. The guidance for “Fair Value Measurement and Disclosure” provides a framework for measuring fair value by creating a hierarchy of fair value measurements that distinguishes market data between observable independent market inputs and unobservable market assumptions by the reporting entity. The guidance further expands disclosures about such fair value measurements. The guidance applies broadly to most existing accounting pronouncements that require or permit fair value measurements (including both financial and non-financial assets and liabilities) but does not require any new fair value measurements. The Company has adopted all authoritative guidance in effect as of the balance sheet date regarding certain market conditions that allow for fair value measurements that incorporate unobservable inputs where active market transaction based measurements are unavailable.
Derivative instruments	Fair Value Hedges
	The Company uses derivative instruments in the form of foreign currency forward exchange contracts to manage foreign currency risk. A foreign currency forward exchange contract involves an obligation to purchase or sell a specified amount of a specified currency at a future date at a price set at the time of the contract. Foreign currency forward exchange contracts will not eliminate fluctuations in the value of our assets and liabilities denominated in foreign currencies but rather allow the Company to establish a rate of exchange for a future point in time. The foreign currency forward exchange contracts are recorded as derivatives at fair value as either assets or liabilities, depending on their rights or obligations, with changes in fair value recorded as a net foreign exchange gain or loss in the Company’s Statements of Comprehensive Income.
	To qualify for hedge accounting treatment, a derivative must be highly effective in mitigating the designated changes in value or cash flow of the hedged item. The Company formally documents all relationships between designated hedging instruments and hedged items, as well as its risk management objective and strategy for undertaking various hedge transactions. The documentation process includes linking derivatives to specific assets or liabilities on the balance sheet. The Company also formally assesses, both at the hedge’s inception and on an ongoing basis, whether the derivatives that are used in hedging transactions are highly effective in offsetting changes in fair values or cash flows of hedged items. The Company assesses the effectiveness of its designated hedges on an individual currency basis. If the ratio obtained with this method is within the range of 80% to 125%, the Company considers the hedge effective.
	The Company discontinues hedge accounting prospectively when it is determined that the derivative is no longer highly effective in offsetting changes in the fair value or cash flows of a hedged item; the derivative is de-designated as a hedging instrument; or the derivative expires or is sold, terminated or exercised. To the extent that the Company discontinues hedge accounting, because, based on management’s assessment, the derivative no longer qualifies as an effective hedge, the derivative will continue to be carried in the Consolidated Balance Sheets at its fair value, with changes in its fair value recognized in current period net income through foreign exchange gains (losses).
	Cash Flow Hedges
	The Company uses derivative instruments in the form of interest rate swaps to manage the interest rate exposure associated with certain assets and liabilities. These derivatives are recorded at fair value. Changes in the fair value of a derivative that is designated and qualifies as a cash flow hedge are recorded in other comprehensive income (“OCI”) and are reclassified into earnings when the variability of the cash flow of the hedged item impacts earnings. Gains and losses on derivative contracts that are reclassified from OCI to current period earnings are included in the line item in the Consolidated Statements of Comprehensive Income in which the cash flows of the hedged item are recorded. Any hedge ineffectiveness is recorded immediately in current period earnings.
	To qualify for hedge accounting treatment, a derivative must be highly effective in mitigating the designated changes in value or cash flow of the hedged item. The Company formally documents all relationships between designated hedging instruments and hedged items, as well as its risk management objective and strategy for undertaking various hedge transactions. The documentation process includes linking derivatives to specific assets or liabilities on the balance sheet. The Company also formally assesses, both at the hedge's inception and on an ongoing basis (when required), whether the derivatives that are used in hedging transactions are highly effective in offsetting changes in fair values or cash flows of hedged items. The Company assesses the effectiveness of its designated hedges on an individual contract basis. The Company currently applies the long haul method when assessing the hedge's effectiveness.
	The Company discontinues hedge accounting prospectively when it is determined that the derivative is no longer highly effective in offsetting changes in the fair value or cash flows of a hedged item; the derivative is de-designated as a hedging instrument; or the derivative expires or is sold, terminated or exercised. When hedge accounting is discontinued because the Company becomes aware that it is not probable that the forecasted transaction will occur, the derivative continues to be carried on the balance sheet at its fair value, and gains and losses that were accumulated in OCI are recognized immediately in earnings.
Cash and cash equivalents	The Company considers time deposits and money market funds with an original maturity of one month or less as equivalent to cash.
Foreign exchange	The U.S. dollar is the functional currency of the Company and the majority of its subsidiaries. For these companies, monetary assets and liabilities denominated in foreign currencies are revalued at the exchange rates in effect at the balance sheet date and revenues and expenses denominated in foreign currencies are translated at the prevailing exchange rate on the transaction date with the resulting foreign exchange gains and losses included in earnings. Non-monetary assets and liabilities denominated in foreign currencies are revalued at the exchange rate in effect at the time of the underlying transaction.
	Assets and liabilities of subsidiaries whose functional currency is not the U.S. dollar are translated at prevailing year end exchange rates. Revenue and expenses of such foreign operations are translated at average exchange rates during the year. The net effect of translation differences between functional and reporting currencies in foreign operations, net of applicable deferred income taxes, is included in accumulated other comprehensive income ("AOCI").
Stock plans	The Company accounts for its stock plans in accordance with the U.S. GAAP fair value recognition provisions for “Stock Compensation.” Accordingly, the Company recognizes the compensation expense for stock option grants, restricted share grants and performance share awards based on the fair value of the award on the date of grant over the requisite service period.
Warrants	The Company has accounted for certain warrant contracts issued to our sponsoring investors in conjunction with the capitalization of the Company, and which may be settled by the Company using either the physical settlement or net-share settlement methods, in accordance with U.S. GAAP guidance for “Derivatives and Hedging, Contracts in Entity’s Own Equity.” Accordingly, the fair value of these warrants has been recorded in equity as an addition to additional paid-in capital.
Earnings per share	Basic earnings per common share is calculated by dividing net income available to common shareholders by the weighted average number of common shares outstanding. Earnings per diluted common share are based on the weighted average number of common shares and share equivalents excluding any anti-dilutive effects of warrants, options and other awards under stock plans.
Income taxes and uncertain tax provisions	Deferred tax assets and liabilities are recorded in accordance with U.S. GAAP “Income Taxes” guidance. Consistent with this guidance, the Company records deferred income taxes which reflect the tax effect of the temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and their respective tax bases.
	The Company and its Bermuda domiciled subsidiaries are not subject to any income, withholding or capital gains taxes under current Bermuda law. The Company has operations in subsidiary form in various other jurisdictions around the world, including but not limited to the U.K., U.S., Switzerland, Luxembourg and Canada that are subject to relevant taxes in those jurisdictions.
	The Company recognizes the tax benefits of uncertain tax positions only where the position is more likely than not to be sustained upon audit by tax authorities. The Company would recognize accruals for any interest and penalties related to uncertain tax positions in income tax expenses.
Goodwill and intangible assets	The Company accounts for goodwill and other intangible assets recognized in business combinations in accordance with ASC Topic 805 “Business Combinations.”
	A purchase price paid that is in excess of the fair value of the net assets (“goodwill”) arising from a business combination is recorded as an asset, and is not amortized. Where the total fair value of net assets acquired exceeds consideration paid (“negative goodwill”), the acquirer will record a gain as a result of the bargain purchase, to be recognized through the consolidated statements of comprehensive income at the close of the transaction.
	Intangible assets with a finite life are amortized over the estimated useful life of the asset. Intangible assets with an indefinite useful life are not amortized. Refer to Note 6 "Goodwill and other intangible assets" for further information.
	Goodwill and indefinite-lived intangible assets are tested for impairment on an annual basis or more frequently if events or changes in circumstances indicate that the carrying amount may not be recoverable. Such events or circumstances may include an economic downturn in a geographic market or change in the assessment of future operations. In performing this test, the Company may first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount as a basis for determining whether it is necessary to perform the two-step goodwill impairment test described in ASC Topic 350 “Intangibles—Goodwill and Other.” Similarly, the Company may first assess qualitative factors to determine whether it is more likely than not that an indefinite-lived intangible asset is impaired as a basis for determining whether it is necessary to perform the quantitative impairment described in ASC Topic 350 "Intangibles - Goodwill and Other - General Intangibles Other than Goodwill." The factors assessed in making this determination included the overall insurance industry outlook, business strategy, premium rates, earnings sustainability, market capitalization and the regulatory and political environment.
	If the goodwill or intangible asset is impaired, it is written down to its realizable value with a corresponding expense reflected in the Consolidated Statements of Comprehensive Income.
Investments in affiliates	Investments in which the Company has significant influence over the operating and financial policies of the investee are accounted for under the equity method of accounting. Under this method, the Company records its proportionate share of income or loss from such investments in its results for the period.
Variable interest entities	The Company determines whether it has relationships with entities defined as variable interest entities (“VIEs”) in accordance with ASC Topic 810 "Consolidation." Entities that do not have sufficient equity at risk to allow the entity to finance its activities without additional financial support or in which the equity investors, as a group, do not have the characteristic of a controlling financial interest are referred to as variable interest entities. A VIE is consolidated by the variable interest holder that is determined to be the primary beneficiary.
	The primary beneficiary is defined as the variable interest holder that is determined to have the controlling financial interest as a result of having both (i) the power to direct the activities of a VIE that most significantly impact the economic performance of the VIE and (ii) the obligation to absorb losses or right to receive benefits from the VIE that could potentially be significant to the VIE. At inception of the VIE, as well as following an event that requires reassessment, the Company determines whether it is the primary beneficiary based on an analysis of the Company's level of involvement in the VIE, the contractual terms, and the overall structure of the VIE. Those VIEs that have all the attributes of an investment company are assessed under ASC Topic 810, excluding the changes that were as a result of the issuance of FASB Statement No. 167 "Amendments to FASB Interpretation No. 46(R)."
	The Company accounts for its investments in the AlphaCat Insurance Linked Securities (“ILS”) Funds and the BetaCat ILS Funds as variable interest entities. See Note 9 "Investments in affiliates" for further details.
Noncontrolling interest	The Company accounts for its noncontrolling interests in accordance with ASC Topic 810 “Consolidation.” Redeemable noncontrolling interests are presented as a mezzanine item, between liabilities and shareholders' equity, in the Company's Consolidated Balance Sheet and the non-redeemable noncontrolling interests are presented within shareholders' equity in the Company's Consolidated Balance Sheets and Consolidated Statements of Shareholders' Equity. The net (income) loss attributable to noncontrolling interest is presented separately in the Company's Consolidated Statements of Comprehensive Income. Refer to Note 9 "Investments in affiliates" for further details.

Business_combination_Tables

Business combination (Tables)	12 Months Ended
	Dec. 31, 2014
Western World Insurance Group, Inc
Business Acquisition [Line Items]
Composition of purchase price and fair value of net assets acquired	The fair value of net assets acquired, including pro forma GAAP adjustments, are summarized as follows:
	Total purchase price				$	692,305
	Assets acquired
		Cash and cash equivalents	$	48,760
		Investments	1,126,185
		Receivables	37,848
		Other assets	19,418
		Tangible assets acquired			1,232,211
		Intangible asset - State licenses	$	12,325
		Intangible asset - Brand name	5,756
		Intangible asset - Distribution network	4,651
		Intangible asset - Technology	2,323
		Intangible assets acquired			$	25,055
	Liabilities acquired
		Net loss reserves and paid losses recoverable	$	523,315
		Unearned premiums, net of expenses	135,686
		Other liabilities	81,464
		Liabilities acquired			740,465
	Excess purchase price (goodwill)				$	175,504
Pro forma information	The unaudited pro forma data is for informational purposes only and does not necessarily represent results that would have occurred if the transaction had taken place on the basis assumed above.
		Year ended			Year ended
		31-Dec-14			31-Dec-13
		(unaudited)			(unaudited)
	Net premiums earned	$	2,216,349		$	2,325,407
	Net operating income	$	481,179		$	645,696
	Net income	$	448,071		$	561,832
Summary of results of acquired company since acquisition	The following selected audited information has been provided to present a summary of the results of Western World that have been included in the Consolidated Financial Statements for the year ended December 31, 2014.
		From Acquisition Date to
		31-Dec-14
	Net premiums written	$	58,807
	Total revenue	78,325
	Total expenses	(66,882		)
	Net income	$	11,443
Flagstone Reinsurance Holdings Sa
Business Acquisition [Line Items]
Composition of purchase price and fair value of net assets acquired	The composition of the purchase price and the fair value of net assets acquired is summarized as follows:
	Total allocable purchase price
		Flagstone shares outstanding at November 30, 2012	73,852,137
		Exchange ratio	0.1935
		Validus common shares issued, gross of taxes withheld	14,290,389
		Validus share price at acquisition	$	34.87
		Total value of Validus shares issued			$	498,306
		Total cash consideration paid at $2.00 per Flagstone share			147,731
		Total allocable purchase price			646,037
	Tangible assets acquired
		Cash and cash equivalents	$	159,339
		Investments	1,323,002
		Receivables (a)	171,620
		Other assets	129,245
		Tangible assets acquired			$	1,783,206
	Liabilities acquired
		Net loss reserves and paid losses recoverable	$	639,641
		Unearned premiums, net of expenses	104,592
		Debentures payable	250,657
		Other liabilities	98,574
		Liabilities acquired			$	1,093,464
	Net tangible assets acquired, at fair value				689,742
	Bargain purchase gain before establishment of intangible assets				43,705
		Intangible asset—customer relationships and brand name			5,997
	Bargain purchase gain on acquisition of Flagstone				$	49,702
	(a)	Premiums receivable of $171,620 were net of an allowance for doubtful accounts of $2,216.
Components of gain on bargain purchase	The gain on bargain purchase, net of expenses has been presented as a separate line item in the Company’s Consolidated Statements of Comprehensive Income, and is composed of the following:
		Year Ended
		31-Dec-12
	Bargain purchase gain on acquisition of Flagstone	$	49,702
	Transaction expenses	(5,760		)
	Termination expenses	(20,244		)
	Amortization of intangible asset—customer relationships and brand name	(5,997		)
	Gain on bargain purchase, net of expenses	$	17,701
Pro forma information	The following selected unaudited pro forma financial information has been provided to present a summary of the combined results of the Company and Flagstone, assuming the transaction had been effected on January 1, 2011. The unaudited pro forma data is for informational purposes only and does not necessarily represent results that would have occurred if the transaction had taken place on the basis assumed above.
		Year ended			Year ended
		31-Dec-12			31-Dec-11
		(unaudited)			(unaudited)
	Revenues
	Gross premiums written	$	2,536,535		$	2,914,388
	Reinsurance premiums ceded	(397,008		)	(520,506		)
	Net premiums written	2,139,527			2,393,882
	Change in unearned premiums	86,935			(20,261		)
	Net premiums earned	2,226,462			2,373,621
	Net investment income	126,140			143,472
	Net realized gains on investments	63,601			37,366
	Net unrealized gains (losses) on investments	5,654			(47,101		)
	(Loss) from investment affiliate	(964		)	—
	Other income	29,984			11,152
	Foreign exchange gains (losses)	1,363			(26,605		)
	Total revenues	2,452,240			2,491,905
	Expenses
	Losses and loss expenses	1,242,449			1,920,936
	Policy acquisition costs	413,579			429,509
	General and administrative expenses	323,061			282,183
	Share compensation expenses	30,750			35,427
	Transaction expenses	—			17,433
	Finance expenses	64,306			66,485
	Total expenses	2,074,145			2,751,973
	Income before taxes and income from operating affiliates	378,095			(260,068		)
	Tax (expense)	(3,385		)	(773		)
	Income (loss) from operating affiliates	12,868			(922		)
	Net income (loss) from continuing operations	$	387,578		$	(261,763	)
	Net income (loss) from discontinued operations, net of taxes	19,366			(21,662		)
	Net income (loss)	$	406,944		$	(283,425	)
	Net loss (income) attributable to noncontrolling interest	14,685			(24,515		)
	Net income (loss) available (attributable) to Validus	$	421,629		$	(307,940	)
	Basic earnings (loss) per share	$	3.73		$	(3.20	)
	Earnings (loss) per diluted share	$	3.62		$	(3.20	)
Summary of results of acquired company since acquisition	The following selected audited information has been provided to present a summary of the results of Flagstone that have been included within the Validus Re segment in the Consolidated Financial Statements for the year ended December 31, 2012.
		From Acquisition Date to
		31-Dec-12
	Net premiums written	$	11,305
	Total revenue	26,778
	Total expenses	(17,061		)
	Net income	$	9,717

Goodwill_and_other_intangible_1

Goodwill and other intangible assets (Tables)	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Analysis of goodwill by segment	The following table shows an analysis of goodwill by segment:
		Talbot		Western World			Total
	Goodwill at December 31, 2012	$	20,393	$	—		$	20,393
	Acquired during the year	—		—			—
	Goodwill at December 31, 2013	$	20,393	$	—		$	20,393
	Acquired during the year	—		175,504			175,504
	Goodwill at December 31, 2014	$	20,393	$	175,504		$	195,897
Analysis of carrying value and accumulated amortization of intangible assets by type	The gross carrying value and accumulated amortization of intangible assets by type at December 31, 2014 and 2013 are as follows:
		As of December 31, 2014					As of December 31, 2013
		Gross Carrying Amount		Accumulated Amortization			Gross Carrying Amount		Accumulated Amortization
	Finite-lived intangible assets
	Trade name and customer relationships	$	18,189	$	(10,971	)	$	12,433	$	(10,183	)
	Distribution network	39,831		(26,500		)	35,180		(22,866		)
	Technology	2,323		(116		)	—		—
	Total	$	60,343	$	(37,587	)	$	47,613	$	(33,049	)
	Indefinite-lived intangible assets
	Syndicate capacity	$	91,843	n/a			$	91,843	n/a
	State licenses	12,325		n/a			—		n/a
	Total	$	104,168				$	91,843
Estimated remaining amortization expense	The estimated remaining amortization expense for the finite-lived intangible assets is as follows:
		Total
	2015	$	5,663
	2016	5,663
	2017	3,579
	2018	1,501
	2019 and thereafter	6,350
		$	22,756

Investments_Tables

Investments (Tables)	12 Months Ended
	Dec. 31, 2014
Investments [Abstract]
Amortized cost (or cost), gross unrealized gains and (losses) and estimated fair value of investments	The amortized cost (or cost), gross unrealized gains and (losses) and estimated fair value of investments at December 31, 2014 were as follows:
		Amortized Cost or Cost			Gross Unrealized Gains				Gross Unrealized Losses				Estimated Fair Value
	U.S. government and government agency	$	759,232		$	1,755			$	(901	)		$	760,086
	Non-U.S. government and government agency	279,493			1,215				(1,980		)		278,728
	U.S. states, municipalities and political subdivisions	448,668			1,780				(825		)		449,623
	Agency residential mortgage-backed securities	520,685			9,697				(1,151		)		529,231
	Non-agency residential mortgage-backed securities	37,954			369				(516		)		37,807
	U.S. corporate	1,500,963			3,960				(5,217		)		1,499,706
	Non-U.S. corporate	564,386			2,765				(3,989		)		563,162
	Bank loans	457,537			200				(8,733		)		449,004
	Catastrophe bonds	75,822			768				(926		)		75,664
	Asset-backed securities	647,422			1,250				(1,190		)		647,482
	Commercial mortgage-backed securities	242,332			598				(692		)		242,238
	Total fixed maturities	5,534,494			24,357				(26,120		)		5,532,731
	Total short-term investments (a)	1,051,222			13				(161		)		1,051,074
	Other investments
	Fund of hedge funds	2,570			125				(920		)		1,775
	Preferred stock	6,535			—				(201		)		6,334
	Hedge funds (b)	570,371			60,792				(134,203		)		496,960
	Private equity investments	48,995			4,987				(611		)		53,371
	Investment funds	244,506			437				(111		)		244,832
	Mutual funds	6,199			3,540				—				9,739
	Total other investments	879,176			69,881				(136,046		)		813,011
	Total investments including assets held in trust, catastrophe bonds and noncontrolling interest	$	7,464,892		$	94,251			$	(162,327	)		$	7,396,816
	Assets held in trust on behalf of operating affiliates (a)	$	(732,782	)	$	—			$	—			$	(732,782	)
	Catastrophe bonds	$	(75,822	)	$	(768	)		$	926			$	(75,664	)
	Noncontrolling interest (b)	$	(502,830	)	$	(48,446	)		$	120,782			$	(430,494	)
	Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	$	6,153,458		$	45,037			$	(40,619	)		$	6,157,876
	(a)	Included in the short-term investments balance are assets held in trust to support AlphaCat's fully collateralized reinsurance transactions. Also, included in the short-term investments balance are investments held by one AlphaCat ILS fund which is consolidated by the Company but in which the Company has an equity interest of less than 100%. The remaining interests are held by third party investors and included in the Consolidated Balance Sheets as redeemable noncontrolling interest.
	(b)	Included in the hedge funds balance are investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and included in the Consolidated Balance Sheets as noncontrolling interest.
	The amortized cost (or cost), gross unrealized gains and (losses) and estimated fair value of investments at December 31, 2013 were as follows:
		Amortized Cost or Cost			Gross Unrealized Gains				Gross Unrealized Losses				Estimated Fair Value
	U.S. government and government agency	$	1,368,826		$	2,589			$	(6,736	)		$	1,364,679
	Non-U.S. government and government agency	454,578			6,511				(2,021		)		459,068
	U.S. states, municipalities and political subdivisions	42,978			459				(317		)		43,120
	Agency residential mortgage-backed securities	305,450			8,310				(2,261		)		311,499
	Non-agency residential mortgage-backed securities	16,530			143				(914		)		15,759
	U.S. corporate	1,328,960			9,208				(5,684		)		1,332,484
	Non-U.S. corporate	711,581			5,917				(3,173		)		714,325
	Bank loans	712,859			5,659				(1,402		)		717,116
	Catastrophe bonds	72,000			2,551				—				74,551
	Asset-backed securities	509,091			1,409				(843		)		509,657
	Total fixed maturities	5,522,853			42,756				(23,351		)		5,542,258
	Total short-term investments (a)	787,670			45				(1		)		787,714
	Other investments
	Fund of hedge funds	3,141			83				(921		)		2,303
	Hedge funds (b)	584,518			71,641				(95,076		)		561,083
	Private equity investments	12,333			1,410				(258		)		13,485
	Investment funds	117,307			92				—				117,399
	Mutual funds	6,199			3,617				—				9,816
	Total other investments	723,498			76,843				(96,255		)		704,086
	Total investments including assets held in trust, catastrophe bonds and noncontrolling interest	$	7,034,021		$	119,644			$	(119,607	)		$	7,034,058
	Assets held in trust on behalf of operating affiliates (a)	$	(651,715	)	$	—			$	—			$	(651,715	)
	Catastrophe bonds	$	(53,000	)	$	(2,544	)		$	—			$	(55,544	)
	Noncontrolling interest (b)	$	(512,121	)	$	(62,850	)		$	85,569			$	(489,402	)
	Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	$	5,817,185		$	54,250			$	(34,038	)		$	5,837,397
	(a)	Included in the short-term investments balance are assets held in trust to support AlphaCat's fully collateralized reinsurance transactions. Also, included in the short-term investments balance are investments held by two AlphaCat ILS funds which are consolidated by the Company but in which the Company has an equity interest of less than 100%. The remaining interests are held by third party investors and included in the Consolidated Balance Sheets as redeemable noncontrolling interest.
	(b)	Included in the hedge funds balance are investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and included in the Consolidated Balance Sheets as noncontrolling interest.
Investment ratings on fixed maturities	The following table sets forth information regarding the investment ratings of the Company’s fixed maturities portfolio as at December 31, 2014 and 2013.
		December 31, 2014						December 31, 2013
		Estimated Fair Value			% of Total			Estimated Fair Value				% of Total
	AAA	$	2,494,239		45.1	%		$	2,510,781			45.3	%
	AA	848,226			15.4	%		696,998				12.6	%
	A	1,086,091			19.6	%		1,233,716				22.3	%
	BBB	505,208			9.1	%		323,085				5.8	%
	Total investment-grade fixed maturities	4,933,764			89.2	%		4,764,580				86	%
	BB	362,972			6.6	%		354,992				6.4	%
	B	145,240			2.6	%		383,639				6.9	%
	CCC	12,733			0.2	%		2,453				—	%
	CC	3,926			0.1	%		2,496				0.1	%
	C	1,344			—	%		235				—	%
	D/NR	72,752			1.3	%		33,863				0.6	%
	Total non-investment grade fixed maturities	598,967			10.8	%		777,678				14	%
	Total fixed maturities	$	5,532,731		100	%		$	5,542,258			100	%
Fixed maturities investments by contractual maturity	The amortized cost and estimated fair value amounts for fixed maturity securities held at December 31, 2014 and 2013 are shown below by contractual maturity. Actual maturity may differ from contractual maturity because certain borrowers may have the right to call or prepay certain obligations with or without call or prepayment penalties.
		December 31, 2014							December 31, 2013
		Amortized Cost			Estimated Fair Value				Amortized Cost				Estimated Fair Value
	Due in one year or less	$	312,843		$	313,248			$	688,855			$	692,768
	Due after one year through five years	3,163,225			3,159,200				3,603,459				3,613,847
	Due after five years through ten years	497,175			491,870				396,389				395,633
	Due after ten years	112,858			111,655				3,079				3,095
		4,086,101			4,075,973				4,691,782				4,705,343
	Asset-backed and mortgage-backed securities	1,448,393			1,456,758				831,071				836,915
	Total fixed maturities	$	5,534,494		$	5,532,731			$	5,522,853			$	5,542,258
Net investment income	Net investment income was derived from the following sources:
		Year Ended
		December 31, 2014			December 31, 2013				December 31, 2012
	Fixed maturities and short-term investments	$	97,248		$	99,216			$	105,937
	Other investments	5,111			—				2,790
	Restricted cash and cash and cash equivalents	5,178			4,713				7,259
	Securities lending income	11			6				14
	Total gross investment income	107,548			103,935				116,000
	Investment expenses	(7,472		)	(7,863		)		(8,064		)
	Total net investment income	$	100,076		$	96,072			$	107,936
Analysis of net realized gains (losses) and the change in net unrealized (losses) gains on investments	The following represents an analysis of net realized gains (losses) and the change in net unrealized (losses) gains on investments:
		Year Ended
		December 31, 2014			December 31, 2013				December 31, 2012
	Fixed maturities, short-term and other investments
	Gross realized gains (a)	$	31,316		$	31,402			$	38,905
	Gross realized (losses)	(8,221		)	(28,144		)		(20,672		)
	Net realized gains on investments	23,095			3,258				18,233
	Change in net unrealized (losses) gains on investments (a)	(57,973		)	(58,481		)		17,585
	Total net realized and change in net unrealized (losses) gains on investments including assets held in trust, catastrophe bonds and noncontrolling interest	(34,878		)	(55,223		)		35,818
	Assets held in trust on behalf of operating affiliates	—			88				(88		)
	Catastrophe bonds	2,702			(2,258		)		416
	Noncontrolling interest (a)	42,258			1,836				17,263
	Total net realized and change in net unrealized (losses) gains on investments excluding assets held in trust, catastrophe bonds and noncontrolling interest	$	10,082		$	(55,557	)		$	53,409
	(a)	Includes change in net unrealized gains (losses) and realized gains on investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and is included in the Consolidated Statements of Comprehensive Income as net loss (income) attributable to noncontrolling interest.
Investments pledged as collateral under credit facilities	The following tables outline investments pledged as collateral under the Company's credit and other facilities. For further details of the facilities, please refer to Note 19: “Debt and financing arrangements”:
			December 31, 2014
	Description		Commitment			Issued and Outstanding				Investments pledged as collateral
	$400,000 syndicated unsecured letter of credit facility		$	400,000		$	—			$	—
	$525,000 syndicated secured letter of credit facility		525,000			276,455				395,750
	$200,000 secured bi-lateral letter of credit facility		200,000			15,649				35,645
	Talbot FAL facility		25,000			25,000				31,048
	PaCRe senior secured letter of credit facility		10,000			294				—
	AlphaCat Re secured letter of credit facility		30,000			30,000				30,078
	IPC bi-lateral facility		40,000			15,897				99,437
	$375,000 Flagstone bi-lateral facility		375,000			198,389				430,782
			$	1,605,000		$	561,684			$	1,022,740
			December 31, 2013
	Description		Commitment			Issued and Outstanding				Investments pledged as collateral
	$400,000 syndicated unsecured letter of credit facility		$	400,000		$	—			$	—
	$525,000 syndicated secured letter of credit facility		525,000			358,567				507,620
	$200,000 secured bi-lateral letter of credit facility		200,000			16,726				130,256
	Talbot FAL facility		25,000			25,000				30,801
	PaCRe senior secured letter of credit facility		10,000			294				—
	AlphaCat Re secured letter of credit facility		24,800			24,800				24,806
	IPC bi-lateral facility		40,000			20,177				98,465
	$375,000 Flagstone bi-lateral facility		375,000			305,686				454,458
			$	1,599,800		$	751,250			$	1,246,406

Fair_value_measurements_Tables

Fair value measurements (Tables)	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Fair value hierarchy - allocation of investments	At December 31, 2014, the Company’s investments were allocated between Levels 1, 2 and 3 as follows:
		Level 1			Level 2			Level 3			Total
	U.S. government and government agency	$	—		$	760,086		$	—		$	760,086
	Non-U.S. government and government agency	—			278,728			—			278,728
	U.S. states, municipalities and political subdivisions	—			449,623			—			449,623
	Agency residential mortgage-backed securities	—			529,231			—			529,231
	Non-agency residential mortgage-backed securities	—			37,807			—			37,807
	U.S. corporate	—			1,499,706			—			1,499,706
	Non-U.S. corporate	—			563,162			—			563,162
	Bank loans	—			416,256			32,748			449,004
	Catastrophe bonds	—			70,664			5,000			75,664
	Asset-backed securities	—			647,482			—			647,482
	Commercial mortgage-backed securities	—			242,238			—			242,238
	Total fixed maturities	—			5,494,983			37,748			5,532,731
	Total short-term investments (a)	942,716			108,358			—			1,051,074
	Other investments
	Fund of hedge funds	—			—			1,775			1,775
	Preferred stock	—			6,334			—			6,334
	Hedge funds (b)	—			—			496,960			496,960
	Private equity investments	—			—			53,371			53,371
	Investment funds	—			140,045			104,787			244,832
	Mutual funds	—			9,739			—			9,739
	Total other investments	—			156,118			656,893			813,011
	Total investments including assets held in trust, catastrophe bonds and noncontrolling interest	$	942,716		$	5,759,459		$	694,641		$	7,396,816
	Assets held in trust on behalf of operating affiliates (a)	$	(732,782	)	$	—		$	—		$	(732,782	)
	Catastrophe bonds	$	—		$	(70,664	)	$	(5,000	)	$	(75,664	)
	Noncontrolling interest (b)	$	—		$	—		$	(430,494	)	$	(430,494	)
	Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	$	209,934		$	5,688,795		$	259,147		$	6,157,876
	(a)	Included in the short-term investments balance are assets held in trust to support AlphaCat's fully collateralized reinsurance transactions. Also, included in the short-term investments balance are investments held by one AlphaCat ILS fund which is consolidated by the Company but in which the Company has an equity interest of less than 100%. The remaining interests are held by third party investors and included in the Consolidated Balance Sheets as redeemable noncontrolling interest.
	(b)	Included in the hedge funds balance are investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and included in the Consolidated Balance Sheets as noncontrolling interest.
	At December 31, 2013, the Company’s investments were allocated between Levels 1, 2 and 3 as follows:
		Level 1			Level 2			Level 3			Total
	U.S. government and government agency	$	—		$	1,364,679		$	—		$	1,364,679
	Non-U.S. government and government agency	—			459,068			—			459,068
	U.S. states, municipalities and political subdivisions	—			43,120			—			43,120
	Agency residential mortgage-backed securities	—			311,499			—			311,499
	Non-agency residential mortgage-backed securities	—			15,759			—			15,759
	U.S. corporate	—			1,332,484			—			1,332,484
	Non-U.S. corporate	—			714,325			—			714,325
	Bank loans	—			717,116			—			717,116
	Catastrophe bonds	—			74,551			—			74,551
	Asset-backed securities	—			509,657			—			509,657
	Total fixed maturities	—			5,542,258			—			5,542,258
	Total short-term investments (a)	783,151			4,563			—			787,714
	Other investments
	Fund of hedge funds	—			—			2,303			2,303
	Hedge funds (b)	—			—			561,083			561,083
	Private equity investments	—			—			13,485			13,485
	Investment fund	—			117,399			—			117,399
	Mutual funds	—			9,816			—			9,816
	Total other investments	—			127,215			576,871			704,086
	Total investments including assets held in trust, catastrophe bonds and noncontrolling interest	$	783,151		$	5,674,036		$	576,871		$	7,034,058
	Assets held in trust on behalf of operating affiliates (a)	$	(651,715	)	$	—		$	—		$	(651,715	)
	Catastrophe bonds	$	—		$	(55,544	)	$	—		$	(55,544	)
	Noncontrolling interest (b)	$	—		$	—		$	(489,402	)	$	(489,402	)
	Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	$	131,436		$	5,618,492		$	87,469		$	5,837,397
	(a)	Included in the short-term investments balance are assets held in trust to support AlphaCat's fully collateralized reinsurance transactions. Also, included in the short-term investments balance are investments held by two AlphaCat ILS funds which are consolidated by the Company but in which the Company has an equity interest of less than 100%. The remaining interests are held by third party investors and included in the Consolidated Balance Sheets as redeemable noncontrolling interest.
	(b)	Included in the Hedge funds balance are investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and included in the Consolidated Balance Sheets as noncontrolling interest.
Reconciliation of investments measured at fair value on a recurring basis using Level 3 inputs	The following table presents a reconciliation of the beginning and ending balances for all investments measured at fair value on a recurring basis using Level 3 inputs during the years ended December 31, 2014 and 2013:
		Total Fair Market Value
		Year Ended December 31, 2014			Year Ended December 31, 2013
	Level 3 investments—Beginning of year	$	576,871		$	556,234
	Additions to level 3 investments due to Western World acquisition	23,620			—
	Purchases	175,129			99,037
	Sales	(52,351		)	(82,000		)
	Issuances	—			—
	Settlements	(1,500		)	—
	Realized gains	8,216			6,132
	Unrealized losses	(42,047		)	(2,532		)
	Transfers into Level 3 during the year	6,703			—
	Level 3 investments—End of year	$	694,641		$	576,871
	Catastrophe bonds	(5,000		)	—
	Noncontrolling interest (a)	(430,494		)	(489,402		)
	Level 3 investments excluding noncontrolling interest	$	259,147		$	87,469
	(a)	Includes Level 3 investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and included in the Consolidated Balance Sheets as noncontrolling interest.

Investments_in_affiliates_Tabl

Investments in affiliates (Tables)	12 Months Ended
	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Information about the Company's investments in affiliates, including summarized financial information	The following table presents the Company's investments in affiliates as at December 31, 2014 and 2013:
		31-Dec-14			31-Dec-13
	Investment affiliate	$	63,506		$	34,500
	Operating affiliates	197,977			106,743
	Investments in affiliates	$	261,483		$	141,243
Summary of notes payable to AlphaCat entities	The following tables present a reconciliation of the beginning and ending notes payable to operating affiliates for the year ended December 31, 2014 and 2013:
		Year Ended December 31, 2014
		AlphaCat 2013			AlphaCat 2014				AlphaCat ILS funds				Total
	As at December 31, 2013	$	223,809		$	—			$	215,463			$	439,272
	Notes payable to operating affiliates recognized on deconsolidation of AlphaCat ILS fund	—			—				178,837				178,837
	Issuance of notes payable to operating affiliates	—			157,914				522,113				680,027
	Redemption of notes payable to operating affiliates	(223,512		)	—				(393,556		)		(617,068		)
	Foreign exchange gains	(297		)	(530		)		(8,776		)		(9,603		)
	As at December 31, 2014	$	—		$	157,384			$	514,081			$	671,465
		Year Ended December 31, 2013
		AlphaCat 2013			AlphaCat ILS funds				Total
	As at December 31, 2012	$	—		$	—			$	—
	Issuance of notes payable to operating affiliates	223,082			218,044				441,126
	Redemption of notes payable to operating affiliates	—			(3,553		)		(3,553		)
	Foreign exchange losses	727			972				1,699
	As at December 31, 2013	$	223,809		$	215,463			$	439,272
Schedule of income attributable to operating affiliate investors	The following table presents the (income) attributable to operating affiliate investors for the year ended December 31, 2014, 2013 and 2012:
		Years Ended
		December 31,			December 31,				December 31,
		2014			2013				2012
	AlphaCat 2013	$	(14,577	)	$	(47,329	)		$	—
	AlphaCat 2014	(46,100		)	—				—
	AlphaCat ILS funds	(48,722		)	(21,434		)		—
	(Income) attributable to operating affiliate investors	$	(109,399	)	$	(68,763	)		$	—
Investment Affiliates [Member]
Schedule of Equity Method Investments [Line Items]
Reconciliation of beginning and ending investment in affiliate balances	The following table presents a reconciliation of the beginning and ending investments in the Company’s investment affiliate balances for the years ended December 31, 2014 and 2013:
		Year Ended December 31, 2014			Year Ended December 31, 2013
	Investment in affiliate, beginning of year	$	34,500		$	15,218
	Addition due to Western World acquisition	8,127			—
	Capital contributions	12,468			14,492
	Income from investment affiliate	8,411			4,790
	Investment in affiliate, end of year	$	63,506		$	34,500
Information about the Company's investments in affiliates, including summarized financial information	The following table presents the Company’s investment in the Partnership as at December 31, 2014:
		Investment at cost			Voting ownership %			Equity ownership %			Carrying value
	Aquiline Financial Services Fund II L.P.	$	51,001		—	%		8.1	%		$	63,506
	The following table presents the Company’s investment in the Partnership as at December 31, 2013:
		Investment at cost			Voting ownership %			Equity ownership %			Carrying value
	Aquiline Financial Services Fund II L.P.	$	32,110		—	%		6.7	%		$	34,500
Operating Affiliates [Member]
Schedule of Equity Method Investments [Line Items]
Reconciliation of beginning and ending investment in affiliate balances	The following tables present a reconciliation of the beginning and ending investment in operating affiliates for the years ended December 31, 2014 and 2013:
		Year Ended December 31, 2014
		AlphaCat Re 2011			AlphaCat Re 2012				AlphaCat 2013				AlphaCat 2014			AlphaCat 2015		AlphaCat ILS funds			Total
	As at December 31, 2013	$	9,809		$	1,313			$	51,744			$	21,982		$	—	$	21,895		$	106,743
	Purchase of shares	—			—				—				—			25,600		12,000			37,600
	Gain on redemption of shares	—			—				—				—			—		(5,077		)	(5,077		)
	Return of investment	(5,825		)	(1,516		)		(52,762		)		—			—		(12,364		)	(72,467		)
	Fair value of retained interest on deconsolidation of AlphaCat ILS fund	—			—				—				—			—		113,455			113,455
	Income from operating affiliates	622			938				2,086				6,103			—		7,974			17,723
	As at December 31, 2014	$	4,606		$	735			$	1,068			$	28,085		$	25,600	$	137,883		$	197,977
		Year Ended December 31, 2013
		AlphaCat Re 2011			AlphaCat Re 2012				AlphaCat 2013				AlphaCat 2014			AlphaCat ILS fund		Total
	As at December 31, 2012	$	62,792		$	29,319			$	45,000			$	—		$	20,000	$	157,111
	Purchase of shares	—			—				—				22,000			—		22,000
	Return of investment	(54,914		)	(31,743		)		—				—			—		(86,657		)
	Income (loss) from operating affiliates	1,931			3,737				6,744				(18		)	1,895		14,289
	As at December 31, 2013	$	9,809		$	1,313			$	51,744			$	21,982		$	21,895	$	106,743
Information about the Company's investments in affiliates, including summarized financial information	The following table presents the Company's investments in AlphaCat Re 2011, AlphaCat Re 2012, AlphaCat 2013, AlphaCat 2014, AlphaCat 2015 and the AlphaCat ILS funds in the Consolidated Financial Statements as at December 31, 2014:
		Investment in operating affiliates
		Cost			Voting ownership %			Equity ownership %			Carrying value
	AlphaCat Re 2011	$	4,606		43.7	%		22.3	%		$	4,606
	AlphaCat Re 2012	735			49	%		37.9	%		735
	AlphaCat 2013	1,068			40.9	%		19.7	%		1,068
	AlphaCat 2014	22,000			42.3	%		19.6	%		28,085
	AlphaCat 2015	25,600			40	%		20	%		25,600
	AlphaCat ILS funds	133,091			n/a			(a)			137,883
	Total	$	187,100								$	197,977
	(a)	Equity ownership in the funds was 7.9%, 39.7% and 9.1%, respectively as at December 31, 2014.
	The following table presents the Company's investments in AlphaCat Re 2011, AlphaCat Re 2012, AlphaCat 2013, AlphaCat 2014 and the AlphaCat ILS fund in the Consolidated Financial Statements as at December 31, 2013:
		Investment in operating affiliates
		Investment at cost			Voting ownership %			Equity ownership %			Share of net asset value
	AlphaCat Re 2011	$	9,882		43.7	%		22.3	%		$	9,809
	AlphaCat Re 2012	654			49	%		37.9	%		1,313
	AlphaCat 2013	45,000			40.9	%		19.7	%		51,744
	AlphaCat 2014	22,000			42.3	%		19.6	%		21,982
	AlphaCat ILS fund	20,000			n/a			9.1	%		21,895
	Total	$	97,536								$	106,743
	The following table presents certain summarized financial information of the AlphaCat entities as at December 31, 2014 and for the year then ended:
		Combined investees summarized financial data
		Total assets			Total liabilities				Total revenue				Net income
	AlphaCat Re 2011	$	20,469		$	7,931			$	3			$	2,794
	AlphaCat Re 2012	$	3,098		$	1,136			$	—			$	2,477
	AlphaCat 2013	$	5,490		$	65			$	14,221			$	10,595
	AlphaCat 2014	$	193,702		$	4,102			$	45,333			$	31,070
	AlphaCat 2015	$	142,843		$	—			$	—			$	—
	AlphaCat ILS funds (a)	$	1,026,222		$	175,376			$	65,320			$	54,421
	BetaCat ILS funds	22,010			61				32				(51		)
	(a)	AlphaCat ILS funds information includes all funds, including those where the Company is not the primary beneficiary.

Noncontrolling_interest_Tables

Noncontrolling interest (Tables)	12 Months Ended
	Dec. 31, 2014
Noncontrolling Interest [Abstract]
Recondiliation of beginning and ending balances of noncontrolling interest and redeemable noncontrolling interest	The following table presents a reconciliation of the beginning and ending balances of redeemable noncontrolling interest and noncontrolling interest for the years ended December 31, 2014 and 2013:
		Year Ended December 31, 2014
		Redeemable noncontrolling interest			Noncontrolling interest			Total
	As at December 31, 2013	$	86,512		$	497,657		$	584,169
	Issuance of shares	68,200			—			68,200
	Income (loss) attributable to noncontrolling interest	3,598			(39,062		)	(35,464		)
	Adjustment to noncontrolling interest as a result of deconsolidation	(78,354		)	—			(78,354		)
	As at December 31, 2014	$	79,956		$	458,595		$	538,551
		Year Ended December 31, 2013
		Redeemable noncontrolling interest			Noncontrolling interest			Total
	As at December 31, 2012	$	—		$	434,280		$	434,280
	Issuance of shares	92,190			58,500			150,690
	Income attributable to noncontrolling interest	4,818			4,877			9,695
	Redemption of shares	(10,496		)	—			(10,496		)
	As at December 31, 2013	$	86,512		$	497,657		$	584,169

Derivative_instruments_Tables

Derivative instruments (Tables)	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Location and fair value amount of derivative instruments reported on the balance sheet	The following table summarizes information on the classification and amount of the fair value of derivatives not designated as hedging instruments on the Consolidated Balance Sheets at December 31, 2014 and December 31, 2013:
			As at December 31, 2014									As at December 31, 2013
	Derivatives not designated as hedging instruments:		Net Notional Exposure			Asset Derivative at Fair Value (a)			Liability Derivative at Fair Value (a)			Net Notional Exposure		Asset Derivative at Fair Value (a)		Liability Derivative at Fair Value (a)
	Foreign currency forward contracts		$	26,755		$	1,685		$	—		$	—	$	—	$	—
	(a)	Asset and liability derivatives are classified within other assets and accounts payable and accrued expenses respectively on the Consolidated Balance Sheets. The total impact on earnings during the year ended December 31, 2014, recognized in income within other insurance related income and other income, relating to the foreign currency forward contract that was not designated as a hedging instrument was $1,685.
	The following table summarizes information on the classification and amount of the fair value of derivatives designated as hedging instruments on the Consolidated Balance Sheets at December 31, 2014 and December 31, 2013:
			As at December 31, 2014									As at December 31, 2013
	Derivatives designated as hedging instruments:		Net Notional Exposure			Asset Derivative at Fair Value (a)			Liability Derivative at Fair Value (a)			Net Notional Exposure		Asset Derivative at Fair Value (a)		Liability Derivative at Fair Value (a)
	Foreign currency forward contracts		$	189,026		$	401		$	3,136		$	163,576	$	1,167	$	2,313
	Interest rate swap contracts		$	552,263		$	25		$	1,169		$	552,263	$	—	$	911
	(a)	Asset and liability derivatives are classified within other assets and accounts payable and accrued expenses respectively on the Consolidated Balance Sheets.
Location and amount of gains and losses related to derivative instruments reported on in the income statement	The following table provides the total impact on earnings, recognized in income within foreign exchange (losses) gains, relating to the derivative instruments formally designated as fair value hedges along with the impact of the related hedged items for the years ended December 31, 2014, 2013 and 2012:
			Year Ended
	Foreign currency forward contracts		December 31, 2014			December 31, 2013			December 31, 2012
	Amount of (loss) gain recognized in income on derivative		$	(11,789	)	$	1,947		$	1,017
	Amount of gain (loss) on hedged item recognized in income attributable to risk being hedged		$	11,789		$	(1,947	)	$	(912	)
	Amount of gain recognized in income on derivative (ineffective portion)		$	—		$	—		$	105
Location and amount of gains and losses related to derivative instruments reported on in the comprehensive income and earnings	The following table provides the total impact on other comprehensive income (loss) and earnings relating to the derivative instruments formally designated as cash flow hedges along with the impact of the related hedged items for the years ended December 31, 2014, 2013 and 2012:
			Year Ended
	Interest rate swap contracts		December 31, 2014			December 31, 2013			December 31, 2012
	Amount of effective portion recognized in other comprehensive income		$	13,302		$	11,107		$	1,588
	Amount of effective portion subsequently reclassified to earnings		$	(13,074	)	$	(11,107	)	$	(1,588	)
	Amount of ineffective portion excluded from effectiveness testing		$	228		$	—		$	—

Premiums_receivable_Tables

Premiums receivable (Tables)	12 Months Ended
	Dec. 31, 2014
Premiums Receivable Disclosure [Abstract]
Components of premiums receivable	The following is a breakdown of the components of premiums receivable at December 31, 2014 and 2013:
		Premiums			Premiums			Total
		in course			accrued
		of collection			but unbilled
	Balance as at December 31, 2013	$	73,702		$	623,531		$	697,233
	Change during 2014	11,347			(933		)	10,414
	Balance as at December 31, 2014	$	85,049		$	622,598		$	707,647
	Balance as at December 31, 2012	$	214,891		$	587,268		$	802,159
	Change during 2013	(141,189		)	36,263			(104,926		)
	Balance as at December 31, 2013	$	73,702		$	623,531		$	697,233

Reserve_for_losses_and_loss_ex1

Reserve for losses and loss expenses (Tables)	12 Months Ended
	Dec. 31, 2014
Liability for Future Policy Benefits and Unpaid Claims and Claims Adjustment Expense [Abstract]
Reserve for losses and loss expenses	The following table represents an analysis of paid and unpaid losses and loss expenses incurred and a reconciliation of the beginning and ending unpaid losses and loss expenses for the years ended December 31, 2014, 2013 and 2012:
		Years Ended
		31-Dec-14			December 31,			December 31,
					2013			2012
	Reserve for losses and loss expenses, beginning of year	$	3,030,399		$	3,517,573		$	2,631,143
	Losses and loss expenses recoverable	(370,154		)	(439,967		)	(372,485		)
	Net reserves for losses and loss expenses, beginning of year	2,660,245			3,077,606			2,258,658
	Net reserves acquired (disposed)	525,091			(36,519		)	639,641
	Increase (decrease) in net reserves for losses and loss expenses in respect of losses occurring in:
	Current year	1,024,256			999,380			1,174,415
	Prior years (a)	(252,207		)	(205,448		)	(174,969		)
	Total incurred losses and loss expenses (a)	772,049			793,932			999,446
	Less net losses and loss expenses paid in respect of losses occurring in:
	Current year	(245,084		)	(244,682		)	(182,146		)
	Prior years	(816,823		)	(916,796		)	(653,874		)
	Total net paid losses	(1,061,907		)	(1,161,478		)	(836,020		)
	Foreign exchange (gain) loss	(38,550		)	(13,296		)	15,881
	Net reserve for losses and loss expenses, end of year	2,856,928			2,660,245			3,077,606
	Losses and loss expenses recoverable	377,466			370,154			439,967
	Reserve for losses and loss expenses, end of year	$	3,234,394		$	3,030,399		$	3,517,573
	(a)	Upon closing the acquisition of Western World, an adjustment of $15,586 was made to increase net reserves to reflect fair value. This adjustment was amortized to income through a reduction in losses and loss expenses of $4,607 during the year ended December 31, 2014. The remaining fair value adjustment will be amortized in 2015.
	Incurred losses and loss expenses comprise:
		Years Ended
		December 31, 2014 (a)			December 31,			December 31,
					2013			2012
	Gross losses and loss expenses (a)	$	833,860		$	924,986		$	1,192,494
	Reinsurance recoverable	(61,811		)	(131,054		)	(193,048		)
	Net incurred losses and loss expenses (a)	$	772,049		$	793,932		$	999,446
	(a)	Upon closing the acquisition of Western World, an adjustment of $15,586 was made to increase net reserves to reflect fair value. This adjustment was amortized to income through a reduction in losses and loss expenses of $4,607 during the year ended December 31, 2014. The remaining fair value adjustment will be amortized in 2015.
Prior year development by segment and line of business	The net favorable development on prior years by segment and line of business is as follows:
		Year Ended December 31, 2014
		Property			Marine			Specialty			Liability			Total
	Validus Re	$	(76,064	)	$	(6,830	)	$	(4,706	)	$	—		$	(87,600	)
	AlphaCat	(12,201		)	—			—			—			(12,201		)
	Talbot	(53,779		)	(31,397		)	(55,990		)	—			(141,166		)
	Western World (a)	$	1,023		$	—		$	—		$	(12,263	)	$	(11,240	)
	Net favorable development (a)	$	(141,021	)	$	(38,227	)	$	(60,696	)	$	(12,263	)	$	(252,207	)
	(a)	Upon closing the acquisition, an adjustment of $15,586 was made to increase net reserves to reflect fair value. This adjustment was amortized to income through a reduction in losses and loss expenses of $4,607 during the year ended December 31, 2014. The remaining fair value adjustment will be amortized in 2015.
	The Validus Re property lines experienced favorable development primarily due to lower claims emergence on attritional losses and favorable loss development on Hurricane Sandy. The Validus Re marine and specialty lines experienced favorable development primarily due to lower claims emergence on attritional losses. The AlphaCat property lines experienced favorable development primarily due to the release of reserves on one aggregate excess of loss contract. Talbot experienced favorable development across all lines, primarily due to lower than expected claims development on attritional losses. Western World experienced unfavorable development on the property lines and favorable development on the liability lines, primarily due to claims development on attritional losses.
		Year Ended December 31, 2013
		Property			Marine			Specialty			Total (a)
	Validus Re	$	(81,610	)	$	26,705		$	(4,353	)	$	(59,258	)
	Talbot	(45,692		)	(46,092		)	(54,406		)	(146,190		)
	Net favorable development	$	(127,302	)	$	(19,387	)	$	(58,759	)	$	(205,448	)
	(a)	AlphaCat has not had any development on prior accident years.
	The Validus Re property and specialty lines experienced favorable development primarily due to lower claims emergence on attritional losses, although the property lines experienced unfavorable development due to increased estimate of ultimate losses on the New Zealand earthquakes. The Validus Re marine lines experienced unfavorable development primarily due to an increased estimate of ultimate losses on Costa Concordia. Talbot experienced favorable development across all lines, primarily due to lower than expected claims development on attritional losses.
		Year Ended December 31, 2012
		Property			Marine			Specialty			Total (a)
	Validus Re	$	(45,733	)	$	(11,298	)	$	(15,530	)	$	(72,561	)
	Talbot	(26,263		)	(40,060		)	(36,085		)	(102,408		)
	Net favorable development	$	(71,996	)	$	(51,358	)	$	(51,615	)	$	(174,969	)
	(a)	AlphaCat has not had any development on prior accident years.
	The Validus Re property and marine lines experienced favorable development primarily due to a reduction in the loss estimates on attritional losses, partially offset by increases in loss estimates on notable loss events. The Validus Re specialty lines experienced favorable development primarily due to lower than expected claims development on attritional losses. Talbot experienced favorable development across all lines, primarily due to lower than expected development on attritional losses.

Accounts_payable_and_accrued_e1

Accounts payable and accrued expenses (Tables)	12 Months Ended
	Dec. 31, 2014
Accounts Payable and Accrued Liabilities [Abstract]
Components of accounts payable and accrued expenses	The following are the components of accounts payable and accrued expenses:
		Years Ended
		December 31,		December 31,
		2014		2013
	Accrued interest on debt	$	12,224	$	10,686
	Subscriptions received in advance on AlphaCat ILS funds	15,400		35,000
	Accrued income attributable to operating affiliates	109,399		68,763
	Trade and compensation payables	181,222		163,738
	Total accounts payable and accrued expenses	$	318,245	$	278,187

Reinsurance_Tables

Reinsurance (Tables)	12 Months Ended
	Dec. 31, 2014
Reinsurance Disclosures [Abstract]
Effects of reinsurance on premiums written and earned	The effects of reinsurance on premiums written and earned for the years ended December 31, 2014, 2013 and 2012 are as follows:
		Year Ended December 31, 2014
		Validus Re								AlphaCat							Talbot						Western World						Eliminations						Total
		Written				Earned				Written				Earned			Written			Earned			Written			Earned			Written			Earned			Written			Earned
	Direct	$	—			$	—			$	—			$	—		$	617,793		$	576,136		$	65,235		$	80,838		$	—		$	—		$	683,028		$	656,974
	Assumed	1,136,910				1,127,894				135,181				135,884			483,977			508,634			—			—			(75,810		)	(83,168		)	1,680,258			1,689,244
	Ceded	(182,056		)		(210,610		)		(4,348		)		(3,534		)	(192,211		)	(204,996		)	(6,428		)	(7,842		)	75,810			83,168			(309,233		)	(343,814		)
	Total	$	954,854			$	917,284			$	130,833			$	132,350		$	909,559		$	879,774		$	58,807		$	72,996		$	—		$	—		$	2,054,053		$	2,002,404
		Year Ended December 31, 2013
		Validus Re								AlphaCat							Talbot						Eliminations						Total
		Written				Earned				Written				Earned			Written			Earned			Written			Earned			Written			Earned
	Direct	$	—			$	—			$	—			$	—		$	544,722		$	519,045		$	—		$	—		$	544,722		$	519,045
	Assumed	1,242,522				1,360,735				147,009				137,939			547,168			532,069			(80,315		)	(78,833		)	1,856,384			1,951,910
	Ceded	(226,264		)		(226,798		)		(525		)		(525		)	(226,111		)	(220,420		)	80,315			78,833			(372,585		)	(368,910		)
	Total	$	1,016,258			$	1,133,937			$	146,484			$	137,414		$	865,779		$	830,694		$	—		$	—		$	2,028,521		$	2,102,045
		Year Ended December 31, 2012
		Validus Re								AlphaCat							Talbot						Eliminations						Total
		Written				Earned				Written				Earned			Written			Earned			Written			Earned			Written			Earned
	Direct	$	1,551			$	364			$	—			$	—		$	548,940		$	535,508		$	—		$	—		$	550,491		$	535,872
	Assumed	1,130,408				1,174,681				21,603				17,666			529,696			529,544			(65,758		)	(73,934		)	1,615,949			1,647,957
	Ceded	(144,578		)		(151,774		)		—				—			(228,686		)	(232,773		)	65,758			73,934			(307,506		)	(310,613		)
	Total	$	987,381			$	1,023,271			$	21,603			$	17,666		$	849,950		$	832,279		$	—		$	—		$	1,858,934		$	1,873,216
Reinsurance recoverables by reinsurer	Reinsurance recoverables by reinsurer are as follows:
		December 31, 2014							December 31, 2013
		Reinsurance Recoverable				% of Total			Reinsurance Recoverable				% of Total
	Top 10 reinsurers	$	312,205			75.1	%		$	340,938			75.7	%
	Other reinsurers’ balances > $1 million	94,247				22.7	%		100,784				22.4	%
	Other reinsurers’ balances < $1 million	9,092				2.2	%		8,512				1.9	%
	Total	$	415,544			100	%		$	450,234			100	%
			December 31, 2014
	Top 10 Reinsurers		Rating		Reinsurance Recoverable				% of Total
	Swiss Re		AA-		$	70,848			17	%
	Lloyd's Syndicates		A+		62,318				15	%
	Everest Re		A+		51,425				12.4	%
	Hannover Re		AA-		40,927				9.8	%
	Fully Collateralized		NR		23,315				5.6	%
	Munich Re		AA-		19,384				4.7	%
	Transatlantic Re		A+		12,418				3	%
	XL Re		A+		11,114				2.7	%
	Berkshire Hathaway Homestate		AA+		10,372				2.5	%
	Merrimack Mutual Fire Insurance		A+		10,084				2.4	%
	Total				$	312,205			75.1	%
			December 31, 2013
	Top 10 Reinsurers		Rating		Reinsurance Recoverable				% of Total
	Lloyd's Syndicates		A+		$	73,398			16.3	%
	National Indemnity		AA+		51,037				11.3	%
	Everest Re		A+		48,113				10.7	%
	Hannover Re		AA-		41,483				9.2	%
	Fully Collateralized		NR		36,683				8.1	%
	Third Point Re		A-		30,428				6.8	%
	Swiss Re		AA-		20,022				4.5	%
	Transatlantic Re		A+		14,114				3.1	%
	XL Re		A+		13,300				3	%
	Munich Re		AA-		12,360				2.7	%
	Total				$	340,938			75.7	%
	NR: Not rated

Share_capital_Tables

Share capital (Tables)	12 Months Ended
	Dec. 31, 2014
Stockholders' Equity Note [Abstract]
Summary of common shares issued and outstanding	The following table is a summary of the common shares issued and outstanding:
		Common Shares
	Common shares issued, December 31, 2013	154,488,497
	Restricted share awards vested, net of shares withheld	615,659
	Restricted share units vested, net of shares withheld	10,265
	Options exercised	412,656
	Direct issuance of common stock	1,380
	Performance shares vested, net of shares withheld	25,767
	Common shares issued, December 31, 2014	155,554,224
	Treasury shares, December 31, 2014	(71,684,379	)
	Common shares outstanding, December 31, 2014	83,869,845
		Common Shares
	Common shares issued, December 31, 2012	152,698,191
	Restricted share awards vested, net of shares withheld	796,838
	Restricted share units vested, net of shares withheld	14,381
	Options exercised	351,509
	Warrants exercised	591,480
	Direct issuance of common stock	1,266
	Performance shares vested, net of shares withheld	31,897
	Deferred share units vested, net of shares withheld	2,935
	Common shares issued, December 31, 2013	154,488,497
	Treasury shares, December 31, 2013	(58,444,185	)
	Common shares outstanding, December 31, 2013	96,044,312
		Common Shares
	Common shares issued, December 31, 2011	134,503,065
	Restricted share awards vested, net of shares withheld	1,572,634
	Restricted share units vested, net of shares withheld	15,173
	Options exercised	439,065
	Warrants exercised	326,715
	Direct issuance of common stock	15,841,539
	Common shares issued, December 31, 2012	152,698,191
	Treasury shares, December 31, 2012	(44,776,932	)
	Common shares outstanding, December 31, 2012	107,921,259
Assumptions used in warrant-pricing model	The other assumptions in the warrant-pricing model were as follows:
		July 24,			February 3,			December 15,
		2007			2006			2005
		Issuance			Issuance			Issuance
	Warrants issued	256,409			8,593			8,446,727
	Average strike price	$	20		$	17.5		$	17.5
	Volatility	30		%	30		%	30		%
	Risk-free rate	4.5		%	4.5		%	4.5		%
	Expected dividend yield	0		%	0		%	0		%
	Expected term (years)	8			10			10
	Calculated fair value per warrant	$	11.28		$	8.89		$	8.89

Retirement_and_pension_plans_T

Retirement and pension plans (Tables)	12 Months Ended
	Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Summary of assumptions used to determine net periodic pension expense and benefit obligations	The assumptions used to determine net periodic pension expense for the year ended December 31, 2014 are as follows:
		Year Ended December 31, 2014
	Discount rate	3	%
	Increase in compensation levels rate	5	%
	The assumptions used to determine benefit obligations as at December 31, 2014 are as follows:
		As at December 31, 2014
	Discount rate	2.75	%
	Increase in compensation levels rate	5	%
Analysis of the funded status and amounts recognized for defined benefit plans	The following tables present a reconciliation of the beginning and ending funded status and the net amounts recognized for the defined benefit plans for the year ended December 31, 2014:
		Year Ended December 31, 2014 (a)
	Change in benefit obligation:
	Projected benefit obligation as at October 2, 2014	$	20,885
	Service cost	295
	Interest cost	145
	Actuarial losses	1
	Benefit payments	(24		)
	Settlements	(4,809		)
	Projected benefit obligation as at December 31, 2014	$	16,493
	Change in plan assets:
	Fair value of plan assets as at October 2, 2014	$	—
	Employer contributions	6,495
	Benefit payments	(24		)
	Settlements	(6,471		)
	Fair value of plan assets as at December 31, 2014	—
	Funded status as at December 31, 2014	$	(16,493	)
	Current liabilities	$	(559	)
	Noncurrent liabilities	(15,934		)
	Net amount recognized	$	(16,493	)
	Amounts recognized in accumulated other comprehensive (loss) income consist of:
	Net loss	$	4,505
	Prior service credit	(4		)
	Net amount recognized	$	4,501
		As at December 31, 2014
	Projected benefit obligation	$	16,493
	Accumulated benefit obligation	$	11,971
	Fair value of plan assets	$	—
Components of net periodic pension expense	The components of net periodic pension expense for the year ended December 31, 2014 are as follows:
		Year Ended December 31, 2014
	Service cost	$	295
	Interest cost	145
	Amortization of prior service cost	(1		)
	Amortization of net loss	79
	Net periodic benefit cost	518
	Settlement loss	1,322
	Net periodic pension expense	$	1,840
Summary of other changes in plan assets and benefit obligations recognized in other comprehensive income	Other changes in plan assets and benefit obligations recognized in other comprehensive (loss) income are as follows for the year ended December 31, 2014:
		Year Ended December 31, 2014
	Net loss	$	1,961
	Amortization of loss	(317		)
	Amortization of prior service cost	2
	Settlement loss	(1,322		)
	Total recognized in other comprehensive (loss) income	$	324
	Total recognized in net pension expense and other comprehensive (loss) income (before tax effects)	$	2,164
Summary of expected benefit payments	As at December 31, 2014, the projected benefits are as follows:
	2015		$	559
	2016		93
	2017		6,921
	2018		85
	2019		2,160
	2020-2024		5,228
	Total benefit payments required		$	15,046

Stock_plans_Tables

Stock plans (Tables)	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Options, activity during the period	Activity with respect to options for the year ended December 31, 2014 was as follows:
		Options		Weighted Average Grant Date Fair Value				Weighted Average Grant Date Exercise Price			Total		Company Proceeds Received
											Intrinsic Value (a)
	Options outstanding and exercisable, December 31, 2013	1,572,713		$	6.66			$	18.88
	Options exercised	(412,656	)	5.36				22.07			$	7,459	$	9,107
	Options outstanding and exercisable, December 31, 2014	1,160,057		$	7.12			$	17.74
	Activity with respect to options for the year ended December 31, 2013 was as follows:
		Options		Weighted Average Grant Date Fair Value				Weighted Average Grant Date Exercise Price			Total		Company Proceeds Received
											Intrinsic Value (a)
	Options outstanding and exercisable, December 31, 2012	1,823,947		$	6.52			$	20.69
	Options regranted (modified)	1,833,414		6.76				19.02
	Options exercised	(351,509	)	5.94				22.91			$	4,963	$	8,052
	Options cancelled (modified)	(1,733,139	)	6.76				20.12
	Options outstanding and exercisable, December 31, 2013	1,572,713		$	6.66			$	18.88
	Activity with respect to options for the year ended December 31, 2012 was as follows:
		Options		Weighted Average Grant Date Fair Value				Weighted Average Grant Date Exercise Price			Total		Company Proceeds Received
											Intrinsic Value (a)
	Options outstanding and exercisable, December 31, 2011	2,263,012		$	6.69			$	20.12
	Options exercised	(439,065	)	7.44				17.73			$	6,574	$	7,785
	Options outstanding and exercisable, December 31, 2012	1,823,947		$	6.52			$	20.69
	(a)	The total intrinsic value in the tables above represent the amount by which the market price of the Company's common stock is greater than the option strike price multiplied by the number of options exercised during the year.
Restricted share awards, activity during the period	Activity with respect to unvested restricted share awards for the year ended December 31, 2014 was as follows:
		Restricted Share Awards		Weighted Average Grant Date Fair Value
	Restricted share awards outstanding, December 31, 2013	2,684,745		$	33.74
	Restricted share awards granted	1,051,348		37.81
	Restricted share awards vested	(797,446	)	31.44
	Restricted share awards forfeited	(79,936	)	36.09
	Restricted share awards outstanding, December 31, 2014	2,858,711		$	35.81
	Activity with respect to unvested restricted share awards for the year ended December 31, 2013 was as follows:
		Restricted Share Awards		Weighted Average Grant Date Fair Value
	Restricted share awards outstanding, December 31, 2012	2,170,547		$	29.24
	Restricted share awards granted	1,594,672		36.07
	Restricted share awards vested	(969,562	)	28.12
	Restricted share awards forfeited	(110,912	)	28.34
	Restricted share awards outstanding, December 31, 2013	2,684,745		$	33.74
	Activity with respect to unvested restricted share awards for the year ended December 31, 2012 was as follows:
		Restricted Share Awards		Weighted Average Grant Date Fair Value
	Restricted share awards outstanding, December 31, 2011	3,003,547		$	25.77
	Restricted share awards granted	921,506		31.47
	Restricted share awards vested	(1,719,855	)	24.4
	Restricted share awards forfeited	(34,651	)	27.85
	Restricted share awards outstanding, December 31, 2012	2,170,547		$	29.24
Restricted share unit awards, activity during the period	Activity with respect to unvested restricted share units for the year ended December 31, 2014 was as follows:
		Restricted Share Units		Weighted Average Grant Date Fair Value
	Restricted share units outstanding, December 31, 2013	66,518		$	33.74
	Restricted share units granted	53,025		38.1
	Restricted share units vested	(18,325	)	30.71
	Restricted share units issued in lieu of cash dividends	2,266		35
	Restricted share units outstanding, December 31, 2014	103,484		$	36.54
	Activity with respect to unvested restricted share units for the year ended December 31, 2013 was as follows:
		Restricted Share Units		Weighted Average Grant Date Fair Value
	Restricted share units outstanding, December 31, 2012	47,238		$	29.61
	Restricted share units granted	36,635		36.11
	Restricted share units vested	(21,814	)	28.17
	Restricted share units issued in lieu of cash dividends	4,459		30.7
	Restricted share units outstanding, December 31, 2013	66,518		$	33.74
	Activity with respect to unvested restricted share units for the year ended December 31, 2012 was as follows:
		Restricted Share Units		Weighted Average Grant Date Fair Value
	Restricted share units outstanding, December 31, 2011	53,312		$	27.6
	Restricted share units granted	16,633		31.77
	Restricted share units vested	(22,818	)	26.49
	Restricted share units issued in lieu of cash dividends	1,504		28.66
	Restricted share units forfeited	(1,393	)	28.57
	Restricted share units outstanding, December 31, 2012	47,238		$	29.61
Performance share awards, activity during the period	Activity with respect to unvested performance share awards for the year ended December 31, 2014 was as follows:
		Performance Share Awards		Weighted Average Grant Date Fair Value
	Performance share awards outstanding, December 31, 2013	101,820		$	33.56
	Performance share awards granted	52,639		37.33
	Performance share awards vested	(32,746	)	32.62
	Performance share awards conversion adjustment	(15,344	)	31.38
	Performance share awards outstanding, December 31, 2014	106,369		$	36.03
	Activity with respect to unvested performance share awards for the year ended December 31, 2013 was as follows:
		Performance Share Awards		Weighted Average Grant Date Fair Value
	Performance share awards outstanding, December 31, 2012	220,845		$	31.81
	Performance share awards granted	38,386		36.11
	Performance share awards vested	(39,094	)	28.7
	Performance share awards forfeited	(18,701	)	31.05
	Performance share awards conversion adjustment	(99,616	)	33.05
	Performance share awards outstanding, December 31, 2013	101,820		$	33.56
	Activity with respect to unvested performance share awards for the year ended December 31, 2012 was as follows:
		Performance Share Awards		Weighted Average Grant Date Fair Value
	Performance share awards outstanding, December 31, 2011	279,019		$	30.77
	Performance share awards granted	41,128		31.38
	Performance share awards forfeited	(99,302	)	28.7
	Performance share awards outstanding, December 31, 2012	220,845		$	31.81
Total share compensation expenses	The breakdown of share compensation expenses by award type was as follows:
		Years Ended
		December 31, 2014			December 31, 2013				December 31,
									2012
	Options	$	—		$	—			$	142
	Restricted share awards	31,335			27,750				25,145
	Restricted share units	876			585				499
	Performance share awards	862			(705		)		923
	Total	$	33,073		$	27,630			$	26,709

Debt_and_financing_arrangement1

Debt and financing arrangements (Tables)	12 Months Ended
	Dec. 31, 2014
Debt Instrument [Line Items]
Schedule of financing structure	The financing structure at December 31, 2014 was:
		Commitment			Issued and outstanding (a)				Drawn
	2006 Junior Subordinated Deferrable Debentures	$	150,000		$	150,000			$	150,000
	2007 Junior Subordinated Deferrable Debentures	200,000			139,800				139,800
	Flagstone 2006 Junior Subordinated Deferrable Debentures	135,727			135,727				135,727
	Flagstone 2007 Junior Subordinated Deferrable Debentures	113,750			113,750				113,750
	Total debentures payable	599,477			539,277				539,277
	2010 Senior Notes due 2040	250,000			250,000				247,306
	Total debentures and senior notes payable	849,477			789,277				786,583
	$400,000 syndicated unsecured letter of credit facility	400,000			—				—
	$525,000 syndicated secured letter of credit facility	525,000			276,455				—
	$200,000 secured bi-lateral letter of credit facility	200,000			15,649				—
	Talbot FAL facility	25,000			25,000				—
	PaCRe senior secured letter of credit facility	10,000			294				—
	AlphaCat Re secured letter of credit facility	30,000			30,000				—
	IPC bi-lateral facility	40,000			15,897				—
	$375,000 Flagstone bi-lateral facility	375,000			198,389				—
	Total credit and other facilities	1,605,000			561,684				—
	Total debt and financing arrangements	$	2,454,477		$	1,350,961			$	786,583
	The financing structure at December 31, 2013 was:
		Commitment			Issued and outstanding (a)				Drawn
	2006 Junior Subordinated Deferrable Debentures	$	150,000		$	150,000			$	150,000
	2007 Junior Subordinated Deferrable Debentures	200,000			139,800				139,800
	Flagstone 2006 Junior Subordinated Deferrable Debentures	137,866			137,866				137,866
	Flagstone 2007 Junior Subordinated Deferrable Debentures	113,750			113,750				113,750
	Total debentures payable	601,616			541,416				541,416
	2010 Senior Notes due 2040	250,000			250,000				247,198
	Total debentures and senior notes payable	851,616			791,416				788,614
	$400,000 syndicated unsecured letter of credit facility	400,000			—				—
	$525,000 syndicated secured letter of credit facility	525,000			358,567				—
	$200,000 secured bi-lateral letter of credit facility	200,000			16,726				—
	Talbot FAL facility	25,000			25,000				—
	PaCRe senior secured letter of credit facility	10,000			294				—
	AlphaCat Re secured letter of credit facility	24,800			24,800				—
	IPC bi-lateral facility	40,000			20,177				—
	$375,000 Flagstone bi-lateral facility	375,000			305,686				—
	Total credit and other facilities	1,599,800			751,250				—
	Total debt and financing arrangements	$	2,451,416		$	1,542,666			$	788,614
	(a)	Indicates utilization of commitment amount, not necessarily drawn borrowings.
Components of finance expenses	Finance expenses consist of interest on the junior subordinated deferrable debentures and senior notes, the amortization of debt offering costs, credit facilities fees, bank charges, AlphaCat financing fees and Talbot FAL costs as follows:
		Year Ended
		December 31,			December 31,				December 31,
		2014			2013				2012
	2006 Junior Subordinated Deferrable Debentures	$	8,868		$	8,868			$	6,964
	2007 Junior Subordinated Deferrable Debentures	7,341			7,341				8,922
	Flagstone 2006 Junior Subordinated Deferrable Debentures	9,001			8,259				459
	Flagstone 2007 Junior Subordinated Deferrable Debentures	7,129			6,222				327
	2010 Senior Notes due 2040	22,388			22,388				22,388
	Credit facilities	5,516			6,544				11,999
	Bank charges	427			507				269
	AlphaCat ILS funds fees (a)	3,530			3,866				2,432
	Talbot FAL Facility	(346		)	182				97
	Total finance expenses	$	63,854		$	64,177			$	53,857
	(a)	Includes finance expenses incurred by AlphaCat Managers, Ltd. in relation to fund raising for the AlphaCat ILS funds, AlphaCat 2015, AlphaCat 2014 and AlphaCat 2013.
Debt Information At Issuance [Member]
Debt Instrument [Line Items]
Summary of key terms of debt instruments	The following table summarizes the key terms of the Company's senior notes and junior subordinated deferrable debentures as at the issuance date for each placement.
	Description	Issuance date	Commitment		Maturity date	Fixed/Spread			Interest payments due
	2006 Junior Subordinated Deferrable Debentures	June 15, 2006	$	150,000	June 15, 2036	9.069	%	(a)	Quarterly
	Flagstone 2006 Junior Subordinated Deferrable Debentures	August 23, 2006	$	135,727	September 15, 2036	3.54	%	(b)	Quarterly
	2007 Junior Subordinated Deferrable Debentures	June 21, 2007	$	200,000	June 15, 2037	8.48	%	(a)	Quarterly
	Flagstone 2007 Junior Subordinated Deferrable Debentures	June 8, 2007	$	88,750	July 30, 2037	3	%	(b)	Quarterly
	Flagstone 2007 Junior Subordinated Deferrable Debentures	September 20, 2007	$	25,000	September 15, 2037	3.1	%	(b)	Quarterly
	2010 Senior Notes due 2040	January 26, 2010	$	250,000	January 26, 2040	8.875	%	(a)	Semi-annually in arrears
	(a)	Fixed interest rate.
	(b)	Variable interest rate is the three-month LIBOR, reset quarterly, plus spread as noted in the table.
Debt Outstanding [Member]
Debt Instrument [Line Items]
Summary of key terms of debt instruments	The following table summarizes the key terms of the Company's senior notes and junior subordinated deferrable debentures as at December 31, 2014:
	Description	Issuance date	Commitment		Maturity date	Fixed/Spread			Interest payments due
	2006 Junior Subordinated Deferrable Debentures	June 15, 2006	$	150,000	June 15, 2036	5.831	%	(b)	Quarterly
	Flagstone 2006 Junior Subordinated Deferrable Debentures	August 23, 2006	$	135,727	September 15, 2036	6.463	%	(b)	Quarterly
	2007 Junior Subordinated Deferrable Debentures	June 21, 2007	$	200,000	June 15, 2037	5.18	%	(b)	Quarterly
	Flagstone 2007 Junior Subordinated Deferrable Debentures	8-Jun-07	$	88,750	July 30, 2037	5.9	%	(b)	Quarterly
	Flagstone 2007 Junior Subordinated Deferrable Debentures	20-Sep-07	$	25,000	September 15, 2037	5.983	%	(b)	Quarterly
	2010 Senior Notes due 2040	26-Jan-10	$	250,000	January 26, 2040	8.875	%	(a)	Semi-annually in arrears
	(a)	Fixed interest rate.
	(b)	Interest rate has been fixed as a result of interest rate swap contracts entered into by the Company.

Income_taxes_Tables

Income taxes (Tables)	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]	The Company’s income (loss) before income tax for the years ended December 31, 2014, 2013 and 2012 was generated in the following jurisdictions:
		Years Ended
		December 31, 2014			December 31, 2013				December 31, 2012
	Income before tax—Bermuda	$	496,840		$	601,583			$	369,675
	Income before tax—United Kingdom	10,824			4,668				10,277
	(Loss) income before tax—United States	(11,752		)	(464		)		3,075
	Income (loss) before tax—Switzerland	9,941			(225		)		(3,381		)
	Income before tax—Canada	2,773			57				391
	Income (loss) before tax—Other	29,076			(8,401		)		2,502
	Income before tax—Total	$	537,702		$	597,218			$	382,539
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]	Income tax expense (benefit) is comprised of current and deferred tax. Income tax expense (benefit) is as follows:
		Years Ended
		December 31, 2014			December 31, 2013				December 31, 2012
	Current income tax expense (benefit)
	U.S.	$	21,257		$	—			$	(54	)
	Non-U.S.	26,179			1,781				1,382
	Total current income tax expense	$	47,436		$	1,781			$	1,328
	Deferred income tax (benefit) expense
	U.S.	$	(24,998	)	$	880			$	134
	Non-U.S.	(22,283		)	(2,278		)		1,039
	Total deferred income tax (benefit) expense	$	(47,281	)	$	(1,398	)		$	1,173
	Total income tax expense (benefit)
	U.S.	$	(3,741	)	$	880			$	80
	Non-U.S.	3,896			(497		)		2,421
	Total income tax expense	$	155		$	383			$	2,501
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	The table below is a reconciliation of the actual income tax expense for the years ended December 31, 2014, 2013 and 2012 to the amount computed by applying the effective tax rate of 0% under Bermuda law to income before taxes:
		Years Ended
		December 31, 2014			December 31, 2013				December 31, 2012
	Expected tax expense at Bermuda statutory rate of 0%	$	—		$	—			$	—
	Foreign tax rate differential	7,993			(2,399		)		4,882
	Change in valuation allowance	(7,284		)	4,967				—
	Tax exempt income and expenses not deductible	(6,055		)	(263		)		—
	Share compensation tax windfall	3,513			—				—
	Impact of enacted changes in tax rates	250			(407		)		(1,611		)
	Prior years tax adjustments	666			(461		)		(770		)
	Other	1,072			(1,054		)		—
	Actual income tax expense	$	155		$	383			$	2,501
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]	Significant components of the Company’s deferred tax assets and liabilities at December 31, 2014 and 2013 were as follows:
		Years Ended
		December 31, 2014			December 31, 2013
	Deferred tax asset
	Tax losses carried forward	$	158,789		$	185,955
	Deferred compensation	5,527			6,119
	Tax credits carried forward	4,016			—
	Discounting of loss reserves	13,721			—
	Risk premium reserve	3,842			—
	Unearned premiums reserve	8,505			—
	Pension	5,864			—
	Other	6,023			128
	Deferred tax asset, gross of valuation allowance	206,287			192,202
	Valuation allowance	158,099			177,656
	Net deferred tax asset	$	48,188		$	14,546
	Deferred tax liability
	Lloyd's underwriting profit taxable in future periods	$	636		$	28,945
	Deferred acquisition costs	3,348			—
	Intangibles	8,638			—
	Unrealized appreciation on investments	9,101			—
	Properties and fixed assets	4,993			3,179
	Other	3,192			1,508
	Deferred tax liability	29,908			33,632
	Net deferred tax asset (liability)	$	18,280		$	(19,086	)
Schedule of Net Operating Loss and Capital Loss Carryforwards [Table Text Block]	As of December 31, 2014, the Company had net operating and capital loss carry forwards inclusive of cumulative currency translation adjustments as follows:
	Tax Jurisdiction		Losses carried forward		Tax effect			Expiration
	United Kingdom		547		118			None
	United States		6,634		2,322			2029 - 2033
	Switzerland		267,420		56,426			2018 - 2020
	Luxembourg		340,245		99,352			None
	Singapore		5,723		572			None

Accumulated_other_comprehensiv1

Accumulated other comprehensive (loss) (Tables)	12 Months Ended
	Dec. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Abstract]
Schedule of changes in AOCI	The changes in accumulated other comprehensive loss, by component for the years ended December 31, 2014, 2013 and 2012 are as follows:
		Foreign currency items			Decrease in minimum pension liability			Gains and losses on cash flow hedge			Total
	Balance, net of tax December 31, 2011	$	(6,601	)	$	—		$	—		$	(6,601	)
	Net current period other comprehensive income, net of tax	3,648			—			—			3,648
	Balance, net of tax December 31, 2012	$	(2,953	)	$	—		$	—		$	(2,953	)
	Amounts reclassified to retained earnings	4,290			—			—			4,290
	Net current period other comprehensive loss, net of tax	(1,954		)	—			—			(1,954		)
	Balance, net of tax December 31, 2013	$	(617	)	$	—		$	—		$	(617	)
	Net current period other comprehensive loss, net of tax	(7,501		)	(210		)	(228		)	(7,939		)
	Balance, net of tax December 31, 2014	$	(8,118	)	$	(210	)	$	(228	)	$	(8,556	)

Commitments_and_contingencies_

Commitments and contingencies (Tables)	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Percentage of gross premiums written by broker	The following table shows the percentage of gross premiums written by broker for the years ended December 31, 2014, 2013 and 2012:
		Years Ended
		December 31, 2014		December 31, 2013			December 31, 2012
	Marsh & McLennan	28.5	%	21.8	%		30.1	%
	Aon Benfield Group Ltd.	20.1	%	27.7	%		24.2	%
	Willis Group Holdings Ltd.	18	%	19.4	%		16.4	%
Future minimum lease commitments	Future minimum lease commitments are as follows:
	2015	$	11,094
	2016	8,616
	2017	7,514
	2018	7,350
	2019	7,130
	2020 and thereafter	23,784
		$	65,488
Components of required capital	The amounts of cash, investments and letters of credit provided for each year of account as follows:
		2015 Underwriting Year			2014 Underwriting Year				2013 Underwriting Year
	Talbot FAL facility	$	25,000		$	25,000			$	25,000
	Group funds	570,100			450,000				403,700
	Total	$	595,100		$	475,000			$	428,700

Earnings_per_share_Tables

Earnings per share (Tables)	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Computation of basic and diluted earnings per share	The following table sets forth the computation of basic earnings per share and earnings per diluted share available to common shareholders for the years ended December 31, 2014, 2013 and 2012:
		Years Ended
		December 31, 2014			December 31, 2013			December 31, 2012
	Basic earnings per share
	Net income	$	445,871		$	542,361		$	392,618
	Loss (income) attributable to noncontrolling interest	35,464			(9,695		)	15,820
	Net income available to Validus	$	481,335		$	532,666		$	408,438
	Less: Dividends and distributions declared on outstanding warrants	(6,208		)	(19,214		)	(6,693		)
	Income available to common shareholders	$	475,127		$	513,452		$	401,745
	Weighted average number of common shares outstanding	90,354,745			102,202,274			97,184,110
	Basic earnings per share available to common shareholders	$	5.26		$	5.02		$	4.13
	Earnings per diluted share
	Net income	$	445,871		$	542,361		$	392,618
	Loss (income) attributable to noncontrolling interest	35,464			(9,695		)	15,820
	Net income available to Validus	$	481,335		$	532,666		$	408,438
	Less: Dividends and distributions declared on outstanding warrants	—			(19,214		)	—
	Income available to common shareholders	$	481,335		$	513,452		$	408,438
	Weighted average number of common shares outstanding	90,354,745			102,202,274			97,184,110
	Share equivalents:
	Warrants	2,789,032			—			3,137,956
	Stock options	745,561			1,026,543			769,618
	Unvested restricted shares	800,933			741,472			1,293,239
	Weighted average number of diluted common shares outstanding	94,690,271			103,970,289			102,384,923
	Earnings per diluted share available to common shareholders	$	5.08		$	4.94		$	3.99

Segment_information_Tables

Segment information (Tables)	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Results of operating segments and corporate segment	The following tables summarize the results of our operating segments and "Corporate":
	Year Ended December 31, 2014		Validus Re Segment				AlphaCat Segment				Talbot Segment				Western World Segment (d)				Corporate & Eliminations				Total
	Underwriting income
	Gross premiums written		$	1,136,910			$	135,181			$	1,101,770			$	65,235			$	(75,810	)		$	2,363,286
	Reinsurance premiums ceded		(182,056		)		(4,348		)		(192,211		)		(6,428		)		75,810				(309,233		)
	Net premiums written		954,854				130,833				909,559				58,807				—				2,054,053
	Change in unearned premiums		(37,570		)		1,517				(29,785		)		14,189				—				(51,649		)
	Net premiums earned		917,284				132,350				879,774				72,996				—				2,002,404
	Underwriting deductions
	Losses and loss expenses		307,290				(9,670		)		423,394				51,035				—				772,049
	Policy acquisition costs		141,670				12,673				187,162				3,169				(4,118		)		340,556
	General and administrative expenses		74,739				19,590				150,828				11,121				73,514				329,792
	Share compensation expenses		9,739				501				11,346				135				11,352				33,073
	Total underwriting deductions		533,438				23,094				772,730				65,460				80,748				1,475,470
	Underwriting income (loss)		$	383,846			$	109,256			$	107,044			$	7,536			$	(80,748	)		$	526,934
	Net investment income		74,599				4,276				20,575				4,523				(3,897		)		100,076
	Other insurance related income (loss)		3,159				27,122				1,095				264				(9,658		)		21,982
	Finance expenses		(14,727		)		(3,545		)		213				—				(45,795		)		(63,854		)
	Operating income (loss) before taxes, income from operating affiliates and (income) attributable to operating affiliate investors		446,877				137,109				128,927				12,323				(140,098		)		585,138
	Tax benefit (expense)		5,512				—				(3,880		)		(1,422		)		(365		)		(155		)
	Income from operating affiliates		—				17,723				—				—				—				17,723
	(Income) attributable to operating affiliate investors		—				(109,399		)		—				—				—				(109,399		)
	Net operating income (loss)		$	452,389			$	45,433			$	125,047			$	10,901			$	(140,463	)		$	493,307
	Net realized gains on investments		7,611				10,935				3,852				697				—				23,095
	Change in net unrealized gains (losses) on investments		8,404				(56,943		)		1,685				(155		)		(10,964		)		(57,973		)
	Income from investment affiliate		8,411				—				—				—				—				8,411
	Foreign exchange (losses) gains		(6,404		)		70				(5,961		)		—				1,665				(10,630		)
	Other (loss)		(2,243		)		—				—				—				—				(2,243		)
	Transaction expenses (a)		—				—				—				—				(8,096		)		(8,096		)
	Net income (loss)		$	468,168			$	(505	)		$	124,623			$	11,443			$	(157,858	)		$	445,871
	Net loss attributable to noncontrolling interest		—				35,464				—				—				—				35,464
	Net income (loss) available (attributable) to Validus		$	468,168			$	34,959			$	124,623			$	11,443			$	(157,858	)		$	481,335
	Selected ratios (b):
	Net premiums written / Gross premiums written		84		%		96.8		%		82.6		%		90.1		%						86.9		%
	Losses and loss expenses		33.5		%		(7.3		)%		48.1		%		69.9		%						38.6		%
	Policy acquisition costs		15.5		%		9.6		%		21.3		%		4.4		%						17		%
	General and administrative expenses (c)		9.2		%		15.2		%		18.4		%		15.4		%						18.1		%
	Expense ratio		24.7		%		24.8		%		39.7		%		19.8		%						35.1		%
	Combined ratio		58.2		%		17.5		%		87.8		%		89.7		%						73.7		%
	Total assets		$	4,209,289			$	1,656,326			$	2,890,123			$	1,492,179			$	63,704			$	10,311,621
	(a)	The transaction expenses relate to costs incurred in connection with the acquisition of Western World, which was completed on October 2, 2014. Transaction expenses are primarily comprised of legal, financial advisory and audit related services.
	(b)	Ratios are based on net premiums earned.
	(c)	The general and administrative expenses ratio includes share compensation expenses.
	(d)	The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.
	Year Ended December 31, 2013		Validus Re Segment				AlphaCat Segment				Talbot Segment				Corporate & Eliminations				Total
	Underwriting income
	Gross premiums written		$	1,242,522			$	147,009			$	1,091,890			$	(80,315	)		$	2,401,106
	Reinsurance premiums ceded		(226,264		)		(525		)		(226,111		)		80,315				(372,585		)
	Net premiums written		1,016,258				146,484				865,779				—				2,028,521
	Change in unearned premiums		117,679				(9,070		)		(35,085		)		—				73,524
	Net premiums earned		1,133,937				137,414				830,694				—				2,102,045
	Underwriting deductions
	Losses and loss expenses		430,026				17,569				346,337				—				793,932
	Policy acquisition costs		180,779				13,853				170,738				(5,060		)		360,310
	General and administrative expenses		91,260				18,765				136,458				68,782				315,265
	Share compensation expenses		7,668				468				9,613				9,881				27,630
	Total underwriting deductions		709,733				50,655				663,146				73,603				1,497,137
	Underwriting income (loss)		$	424,204			$	86,759			$	167,548			$	(73,603	)		$	604,908
	Net investment income		81,346				3,865				18,061				(7,200		)		96,072
	Other insurance related income (loss)		19,222				26,424				1,819				(28,345		)		19,120
	Finance expenses		(16,111		)		(5,734		)		(259		)		(42,073		)		(64,177		)
	Operating income (loss) before taxes, income from operating affiliates and (income) attributable to operating affiliate investors		508,661				111,314				187,169				(151,221		)		655,923
	Tax benefit (expense)		272				—				(671		)		16				(383		)
	Income from operating affiliates		—				14,289				—				—				14,289
(Income) attributable to operating affiliate investors		—				(68,763		)		—				—				(68,763		)
Net operating income (loss)		$	508,933			$	56,840			$	186,498			$	(151,205	)		$	601,066
Net realized (losses) gains on investments		(1,382		)		4,084				556				—				3,258
Change in net unrealized losses on investments		(41,388		)		(3,893		)		(13,200		)		—				(58,481		)
Income from investment affiliate		4,790				—				—				—				4,790
Foreign exchange gains (losses)		7,394				(816		)		(3,531		)		(542		)		2,505
Other income		(10,777		)		—				—				—				(10,777		)
Net income (loss)		$	467,570			$	56,215			$	170,323			$	(151,747	)		$	542,361
Net (income) attributable to noncontrolling interest		—				(9,695		)		—				—				(9,695		)
Net income (loss) available (attributable) to Validus		$	467,570			$	46,520			$	170,323			$	(151,747	)		$	532,666
Selected ratios (a):
Net premiums written / Gross premiums written		81.8		%		99.6		%		79.3		%						84.5		%
Losses and loss expenses		37.9		%		12.8		%		41.7		%						37.8		%
Policy acquisition costs		16		%		10.1		%		20.5		%						17.1		%
General and administrative expenses (b)		8.7		%		14		%		17.6		%						16.3		%
Expense ratio		24.7		%		24.1		%		38.1		%						33.4		%
Combined ratio		62.6		%		36.9		%		79.8		%						71.2		%
Total assets		$	5,326,076			$	1,558,453			$	2,891,682			$	70,221			$	9,846,432
(a)	Ratios are based on net premiums earned.
(b)	The general and administrative expenses ratio includes share compensation expenses.
Year Ended December 31, 2012		Validus Re Segment				AlphaCat Segment				Talbot Segment				Corporate &				Total
														Eliminations
Underwriting income
Gross premiums written		$	1,131,959			$	21,603			$	1,078,636			$	(65,758	)		$	2,166,440
Reinsurance premiums ceded		(144,578		)		—				(228,686		)		65,758				(307,506		)
Net premiums written		987,381				21,603				849,950				—				1,858,934
Change in unearned premiums		35,890				(3,937		)		(17,671		)		—				14,282
Net premiums earned		1,023,271				17,666				832,279				—				1,873,216
Underwriting deductions
Losses and loss expenses		575,416				—				424,030				—				999,446
Policy acquisition costs		154,362				1,774				183,926				(5,364		)		334,698
General and administrative expenses		63,048				7,532				133,281				59,791				263,652
Share compensation expenses		7,763				279				7,789				10,878				26,709
Total underwriting deductions		800,589				9,585				749,026				65,305				1,624,505
Underwriting income (loss)		$	222,682			$	8,081			$	83,253			$	(65,305	)		$	248,711
Net investment income		88,727				3,748				21,310				(5,849		)		107,936
Other insurance related income (loss)		5,000				23,229				2,033				(7,951		)		22,311
Finance expenses		(8,943		)		(3,061		)		(162		)		(41,691		)		(53,857		)
Operating income (loss) before taxes and income from operating affiliates		307,466				31,997				106,434				(120,796		)		325,101
Tax (expense)		(168		)		—				(2,229		)		(104		)		(2,501		)
Income from operating affiliates		—				12,580				—				—				12,580
Net operating income (loss)		$	307,298			$	44,577			$	104,205			$	(120,900	)		$	335,180
Gain on bargain purchase, net of expenses (a)		—				—				—				17,701				17,701
Net realized gains on investments		12,026				216				5,991				—				18,233
Net unrealized (losses) on investments		35,033				(19,509		)		2,061				—				17,585
Loss from investment affiliate		(964		)		—				—				—				(964		)
Foreign exchange (losses) gains		2,664				44				2,527				(437		)		4,798
Other income		85				—				—				—				85
Net income (loss)		$	356,142			$	25,328			$	114,784			$	(103,636	)		$	392,618
Net loss attributable to noncontrolling interest		—				15,820				—				—				15,820
Net income (loss) available (attributable) to Validus		$	356,142			$	41,148			$	114,784			$	(103,636	)		$	408,438
Selected ratios: (b)
Net premiums written / Gross premiums written		87.2		%		100		%		78.8		%						85.8		%
Losses and loss expenses		56.2		%		—		%		50.9		%						53.4		%
Policy acquisition costs		15.1		%		10		%		22.1		%						17.9		%
General and administrative expenses (c)		6.9		%		44.2		%		16.9		%						15.5		%
Expense ratio		22		%		54.2		%		39		%						33.4		%
Combined ratio		78.2		%		54.2		%		89.9		%						86.8		%
Total assets		$	6,206,084			$	805,513			$	2,968,224			$	40,443			$	10,020,264
(a)	The gain on bargain purchase, net of expenses, arose from the acquisition of Flagstone Reinsurance Holdings S.A. on November 30, 2012 and is net of transaction related expenses which included legal, financial advisory, audit related services and termination expenses.
(b)	Ratios are based on net premiums earned.
(c)	The general and administrative expenses ratio includes share compensation expenses.
Gross premiums written by line of business	The following table sets forth the gross premiums written by line of business for the periods indicated:
			Gross Premiums Written (a)
			Year Ended December 31, 2014				Year Ended December 31, 2013				Year Ended December 31, 2012
	Property		$	1,054,530			$	1,164,687			$	1,060,297
	Marine		576,478				570,008				649,421
	Specialty		677,026				666,411				456,722
	Liability		55,252				—				—
			$	2,363,286			$	2,401,106			$	2,166,440
	(a)	The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.
Gross premiums written allocated to the territory of coverage exposure	The following tables set forth the gross premiums written allocated to the territory of coverage exposure for the periods indicated:
		Gross Premiums Written
		Year Ended December 31, 2014
		Validus Re				AlphaCat				Talbot				Western World (d)				Eliminations				Total				%
	United States	$	442,314			$	30,987			$	108,458			$	65,235			$	(11,026	)		$	635,968			27	%
	Worldwide excluding United States (a)	76,129				7,331				139,570				—				(1,334		)		221,696				9.4	%
	Australia and New Zealand	20,257				1,019				9,736				—				—				31,012				1.3	%
	Europe	58,236				3,005				45,615				—				(2,305		)		104,551				4.4	%
	Latin America and Caribbean	54,053				—				116,281				—				(23,958		)		146,376				6.2	%
	Japan	43,310				608				4,116				—				(608		)		47,426				2	%
	Canada	3,670				215				10,194				—				(214		)		13,865				0.6	%
	Rest of the world (b)	21,467				—				93,012				—				—				114,479				4.8	%
	Sub-total, non United States	277,122				12,178				418,524				—				(28,419		)		679,405				28.7	%
	Worldwide including United States (a)	179,564				92,016				96,187				—				(22,463		)		345,304				14.6	%
	Other locations non-specific (c)	237,910				—				478,601				—				(13,902		)		702,609				29.7	%
	Total	$	1,136,910			$	135,181			$	1,101,770			$	65,235			$	(75,810	)		$	2,363,286			100	%
		Gross Premiums Written
		Year Ended December 31, 2013
		Validus Re				AlphaCat				Talbot				Eliminations				Total				%
	United States	$	524,776			$	50,848			$	93,357			$	(6,565	)		$	662,416			27.7	%
	Worldwide excluding United States (a)	63,643				14,801				142,294				(1,485		)		219,253				9.1	%
	Australia and New Zealand	22,275				2,216				11,097				—				35,588				1.5	%
	Europe	65,861				2,533				51,667				(1,446		)		118,615				4.9	%
	Latin America and Caribbean	50,522				—				155,798				(52,267		)		154,053				6.4	%
	Japan	42,729				653				5,971				(653		)		48,700				2	%
	Canada	3,688				818				10,768				(818		)		14,456				0.6	%
	Rest of the world (b)	24,337				—				92,652				—				116,989				4.9	%
	Sub-total, non United States	273,055				21,021				470,247				(56,669		)		707,654				29.4	%
	Worldwide including United States (a)	177,539				75,140				80,538				(8,996		)		324,221				13.5	%
	Other locations non-specific (c)	267,152				—				447,748				(8,085		)		706,815				29.4	%
	Total	$	1,242,522			$	147,009			$	1,091,890			$	(80,315	)		$	2,401,106			100	%
		Gross Premiums Written
		Year Ended December 31, 2012
		Validus Re				AlphaCat				Talbot				Eliminations				Total				%
	United States	$	463,384			$	12,638			$	77,561			$	(1,942	)		$	551,641			25.4	%
	Worldwide excluding United States (a)	24,119				279				156,593				—				180,991				8.4	%
	Australia and New Zealand	—				217				12,851				—				13,068				0.6	%
	Europe	87,805				1,332				50,262				—				139,399				6.4	%
	Latin America and Caribbean	80,432				—				149,091				(53,565		)		175,958				8.1	%
	Japan	30,386				—				6,630				—				37,016				1.7	%
	Canada	—				—				12,243				—				12,243				0.6	%
	Rest of the world (b)	68,754				—				91,130				—				159,884				7.4	%
	Sub-total, non United States	291,496				1,828				478,800				(53,565		)		718,559				33.2	%
	Worldwide including United States (a)	102,080				7,137				65,084				(4,038		)		170,263				7.9	%
	Other locations non-specific (c)	274,999				—				457,191				(6,213		)		725,977				33.5	%
	Total	$	1,131,959			$	21,603			$	1,078,636			$	(65,758	)		$	2,166,440			100	%
	(a)	Represents risks in two or more geographic zones.
	(b)	Represents risks in one geographic zone.
	(c)	The Other locations non-specific category refers to business for which an analysis of exposure by geographic zone is not applicable, such as marine and aerospace risks, since these exposures can span multiple geographic areas and, in some instances, are not fixed locations.
	(d)

Statutory_and_regulatory_requi1

Statutory and regulatory requirements (Tables)	12 Months Ended
	Dec. 31, 2014
Statutory and regulatory requirements [Abstract]
Statutory amounts based on regulatory requirements	The statutory capital and surplus in certain of our most significant regulatory jurisdictions as at December 31, 2014 and 2013 was as follows:
		Bermuda (a)				United States (b)				Switzerland (c)
		December 31,				December 31,				December 31,
		2014		2013		2014		2013		2014		2013
	Required statutory capital and surplus	$	586,641	$	1,390,179	$	95,963	$	—	$	205,563	$	312,563
	Actual statutory capital and surplus	3,793,329		3,884,572		452,089		—		701,010		939,609
	(a)	The Company's Bermuda based insurance subsidiaries are required to maintain minimum statutory capital and surplus equal to the greater of a minimum solvency margin ("MSM") and the Enhanced Capital Requirement ("ECR") where applicable. The ECR is equal to the higher of each insurer's MSM or the Bermuda Solvency Capital Requirement ("BSCR") model or approved internal capital model. The BSCR for the relevant insurers for the year ended December 31, 2014 will not be filed with the BMA until April 2015. As a result, the required statutory capital and surplus as at December 31, 2014 is based on the MSM of all relevant insurers, whereas the required statutory capital and surplus as at December 31, 2013 is based on the MSM and ECR where applicable for all relevant insurers. Required statutory capital and surplus includes Validus Reinsurance, Ltd., Validus Reinsurance (Switzerland) Ltd (Bermuda Branch), PaCRe, Ltd., IPCRe Limited, Validus Re Americas, Ltd., Talbot Insurance (Bermuda), Ltd., AlphaCat Reinsurance, Ltd. and Mont Fort Re Ltd. Actual statutory capital and surplus includes Validus Reinsurance, Ltd., AlphaCat Reinsurance, Ltd. and Talbot Insurance (Bermuda), Ltd. Validus Reinsurance, Ltd. is the parent company of the other five Bermuda based insurance subsidiaries.
	(b)	Required statutory capital and surplus is based on the Risk-Based Capital ("RBC") requirements and includes Western World Insurance Company, Tudor Insurance Company and Stratford Insurance Company. Actual statutory capital and surplus includes Western World Insurance Company. Western World Insurance Company is the parent Company of the other two U.S. based insurance subsidiaries. The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.
	(c)	Required statutory capital and surplus is based on the Target Capital ("TC") requirements calculated under the Swiss Solvency Test ("SST"). Required and actual statutory capital and surplus includes Validus Reinsurance (Switzerland) Ltd (formerly Flagstone Réassurance Suisse SA).
	During 2015, the Company's regulated subsidiaries have the ability to distribute up to $1,013,379 of unrestricted net assets as dividend payments and/or return of capital to Validus Holdings, Ltd. (2014: $516,854) without prior regulatory approval. During the year ended December 31, 2014, actual dividends and distributions to Validus Holdings, Ltd. from its subsidiaries were $773,966 (2013: $1,009,000).
	Statutory net income for the years ended December 31, 2014, 2013 and 2012 was as follows:
		Bermuda (a)						United States (b)						Switzerland (c)
		Year ended December 31,						Year ended December 31,						Year ended December 31,
		2014		2013		2012		2014		2013		2012		2014		2013			2012
	Statutory net income (loss)	$	509,559	$	688,001	$	496,227	$	105,210	$	—	$	—	$	60,308	$	(17,655	)	$	(1,559	)
	(a)	Statutory net income includes Validus Reinsurance, Ltd., PaCRe, Ltd. (at the Company's effective 10% equity interest), IPCRe Limited, Validus Re Americas, Ltd., Talbot Insurance (Bermuda), Ltd., AlphaCat Reinsurance, Ltd. and Mont Fort Re Ltd.
	(b)	Statutory net income includes Western World Insurance Company, Tudor Insurance Company and Stratford Insurance Company. The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.
	(c)	Statutory net income (loss) includes Validus Reinsurance (Switzerland) Ltd (formerly Flagstone Réassurance Suisse SA). The results of Validus Reinsurance (Switzerland) Ltd, a former Flagstone subsidiary, have been included in the Company's consolidated results from the November 30, 2012 date of acquisition.

Condensed_unaudited_quarterly_1

Condensed unaudited quarterly financial information (Tables)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Schedule Of Condensed Quarterly Financial Information [Table Text Block]
		Quarters Ended
		December 31, 2014			September 30, 2014			June 30,			March 31,
								2014			2014
		(unaudited)			(unaudited)			(unaudited)			(unaudited)
	Underwriting income
	Gross premiums written	$	336,647		$	358,974		$	655,674		$	1,011,991
	Reinsurance premiums ceded	(33,623		)	(30,137		)	(50,565		)	(194,908		)
	Net premiums written	303,024			328,837			605,109			817,083
	Change in unearned premiums	255,724			165,859			(139,106		)	(334,126		)
	Net premiums earned	558,748			494,696			466,003			482,957
	Underwriting deductions
	Losses and loss expenses	226,508			224,125			158,745			162,671
	Policy acquisition costs	89,550			86,404			78,953			85,649
	General and administrative expenses	98,186			83,319			73,842			74,445
	Share compensation expenses	8,821			8,764			8,341			7,147
	Total underwriting deductions	423,065			402,612			319,881			329,912
	Underwriting income	$	135,683		$	92,084		$	146,122		$	153,045
	Net investment income	30,167			25,261			21,286			23,362
	Other insurance related income	5,524			3,610			4,811			8,037
	Finance expenses	(16,474		)	(15,354		)	(16,126		)	(15,900		)
	Operating income before taxes, (income) from operating affiliates and (income) loss attributable to operating affiliate investors	$	154,900		$	105,601		$	156,093		$	168,544
	Tax benefit (expense)	243			953			(1,391		)	40
	Income from operating affiliates	4,143			3,761			4,892			4,927
	(Income) attributable to operating affiliate investors	(26,566		)	(25,807		)	(25,316		)	(31,710		)
	Net operating income	$	132,720		$	84,508		$	134,278		$	141,801
	Net realized gains on investments	6,902			4,595			7,858			3,740
	Net unrealized (losses) gains on investments	(74,119		)	(84,974		)	45,427			55,693
	Income from investment affiliate	530			1,754			779			5,348
	Foreign exchange gains (losses)	4,131			(11,441		)	3,158			(6,478		)
	Other (loss) income	(770		)	(7,690		)	424			5,793
	Transaction expenses	(4,695		)	(149		)	(3,252		)	—
	Net income (loss)	$	64,699		$	(13,397	)	$	188,672		$	205,897
	Net loss (income) attributable to noncontrolling interest	61,209			53,069			(35,305		)	(43,509		)
	Net income available to Validus	$	125,908		$	39,672		$	153,367		$	162,388
	Earnings per share
	Weighted average number of common shares and common share equivalents outstanding
	Basic	86,421,127			90,593,329			90,952,523			93,451,999
	Diluted	90,948,156			91,939,610			95,276,836			97,799,519
	Basic earnings per share available to common shareholders	$	1.44		$	0.42		$	1.67		$	1.72
	Earnings per diluted share available to common shareholders	$	1.38		$	0.41		$	1.61		$	1.66
	Selected ratios:
	Losses and loss expenses	40.5		%	45.3		%	34.1		%	33.7		%
	Expense ratio	35.2		%	36.1		%	34.5		%	34.6		%
	Combined ratio	75.7		%	81.4		%	68.6		%	68.3		%
		Quarters Ended
		December 31,			September 30,			June 30,			March 31,
		2013			2013			2013			2013
		(unaudited)			(unaudited)			(unaudited)			(unaudited)
	Underwriting income
	Gross premiums written	$	237,273		$	356,760		$	702,313		$	1,104,760
	Reinsurance premiums ceded	(24,558		)	(39,415		)	(121,396		)	(187,216		)
	Net premiums written	212,715			317,345			580,917			917,544
	Change in unearned premiums	279,523			213,943			(33,459		)	(386,483		)
	Net premiums earned	492,238			531,288			547,458			531,061
	Underwriting deductions
	Losses and loss expenses	206,152			177,965			265,044			144,771
	Policy acquisition costs	84,647			94,900			87,152			93,611
	General and administrative expenses	82,930			81,089			70,967			80,279
	Share compensation expenses	8,147			10,527			6,638			2,318
	Total underwriting deductions	381,876			364,481			429,801			320,979
	Underwriting income	$	110,362		$	166,807		$	117,657		$	210,082
	Net investment income	24,204			20,009			26,210			25,649
	Other insurance related income	7,743			943			5,512			4,922
Finance expenses	(16,925		)	(15,317		)	(17,566		)	(14,369		)
Operating income before taxes, income from operating affiliates and (income) attributable to operating affiliate investors	$	125,384		$	172,442		$	131,813		$	226,284
Tax (expense) benefit	(603		)	(5		)	(93		)	318
Income from operating affiliates	5,510			1,463			3,793			3,523
(Income) attributable to operating affiliate investors (a)	(26,607		)	(11,815		)	(20,264		)	(10,077		)
Net operating income	$	103,684		$	162,085		$	115,249		$	220,048
Net realized gains (losses) on investments	4,448			(6,320		)	3,409			1,721
Net unrealized gains (losses) on investments	20,137			69,967			(141,348		)	(7,237		)
Income from investment affiliate	516			1,044			1,753			1,477
Foreign exchange (losses) gains	(2,230		)	6,036			(8,223		)	6,922
Other loss	(3,697		)	(3,749		)	(1,094		)	(2,237		)
Net income (loss)	$	122,858		$	229,063		$	(30,254	)	$	220,694
Net (income) loss (available) attributable to noncontrolling interest	(27,526		)	(45,694		)	60,976			2,549
Net income available to Validus	$	95,332		$	183,369		$	30,722		$	223,243
Earnings per share
Weighted average number of common shares and common share equivalents outstanding
Basic	98,454,907			99,834,563			103,133,188			107,386,438
Diluted	102,928,482			103,613,766			104,734,643			110,052,999
Basic earnings per share available to common shareholders	$	0.95		$	1.82		$	0.28		$	1.94
Earnings per diluted share available to common shareholders	$	0.93		$	1.77		$	0.28		$	1.9
Selected Ratios:
Losses and loss expenses	41.9		%	33.5		%	48.4		%	27.3		%
Expense ratio	35.7		%	35.1		%	30.1		%	33.2		%
Combined ratio	77.6		%	68.6		%	78.5		%	60.5		%
(a)	This amount had been shown within finance expenses for each of the three months ended March 31, June 30 and September 30, 2013.
	Quarters Ended
	December 31, 2012			September 30, 2012			June 30,			March 31,
							2012			2012
	(unaudited)			(unaudited)			(unaudited)			(unaudited)
Underwriting income
Gross premiums written	$	311,847		$	390,215		$	627,089		$	837,289
Reinsurance premiums ceded	(35,659		)	(45,743		)	(119,052		)	(107,052		)
Net premiums written	276,188			344,472			508,037			730,237
Change in unearned premiums	223,098			130,632			(60,410		)	(279,038		)
Net premiums earned	499,286			475,104			447,627			451,199
Underwriting deductions
Losses and loss expenses	458,310			155,455			153,692			231,989
Policy acquisition costs	81,814			98,623			76,129			78,132
General and administrative expenses	65,095			70,547			61,635			66,375
Share compensation expenses	7,126			7,345			6,800			5,438
Total underwriting deductions	612,345			331,970			298,256			381,934
Underwriting (loss) income	$	(113,059	)	$	143,134		$	149,371		$	69,265
Net investment income	28,802			25,489			25,885			27,760
Other insurance related income	144			7,324			6,606			8,237
Finance expenses	(14,510		)	(9,362		)	(13,706		)	(16,279		)
Operating (loss) income before taxes and (loss) income from operating affiliates	$	(98,623	)	$	166,585		$	168,156		$	88,983
Tax expense	(615		)	(1,343		)	(404		)	(139		)
(Loss) income from operating affiliates	$	(614	)	$	6,235		$	3,592		$	3,367
Net operating (loss) income	$	(99,852	)	$	171,477		$	171,344		$	92,211
Gain on bargain purchase, net of expenses (a)	21,485			(3,784		)	—			—
Net realized (losses) gains on investments	(4,516		)	9,063			6,154			7,532
Net unrealized (losses) gains on investments	(35,857		)	86,345			(53,574		)	20,671
Loss from investment affiliate	(406		)	(160		)	(398		)	—
Foreign exchange gains (losses)	1,181			1,103			(652		)	3,166
Other income (loss)	43			—			(612		)	654
Net (loss) income	$	(117,922	)	$	264,044		$	122,262		$	124,234
Net loss (income) attributable (available) to noncontrolling interest	27,206			(56,746		)	45,360			—
Net (loss) income (attributable) available to Validus	$	(90,716	)	$	207,298		$	167,622		$	124,234
Earnings per share
Weighted average number of common shares and common share equivalents outstanding
Basic	97,688,338			93,368,775			98,254,186			99,425,140
Diluted	97,688,338			98,236,490			103,667,967			105,096,090
Basic (loss) earnings per share (attributable) available to common shareholders	$	(0.94	)	$	2.2		$	1.69		$	1.23
(Loss) earnings per diluted share (attributable) available to common shareholders	$	(0.94	)	$	2.11		$	1.62		$	1.18
Selected Ratios:
Losses and loss expenses	91.8		%	32.7		%	34.3		%	51.4		%
Expense ratio	30.9		%	37.2		%	32.3		%	33.2		%
Combined ratio	122.7		%	69.9		%	66.6		%	84.6		%
(a)	The gain on bargain purchase, net of expenses, arose from the acquisition of Flagstone Reinsurance Holdings S.A. on November 30, 2012 and is net of transaction related expenses which included legal, financial advisory, audit related services and termination expenses.

Condensed_consolidating_financ1

Condensed consolidating financial information (Tables)	12 Months Ended
	Dec. 31, 2014
Condensed Consolidating Financial Information [Abstract]
Condensed consolidating balance sheet
	Condensed Consolidating Balance Sheet	Validus Holdings, Ltd.			Validus Holdings			Other			Consolidating Adjustments (b)			Validus Holdings, Ltd.
	As at December 31, 2014	(Parent Guarantor)			(UK) plc			Validus Holdings, Ltd.						Consolidated
					(Subsidiary Issuer)			Subsidiaries
								(Non-guarantor Subsidiaries) (a)
	Assets
	Fixed maturities, at fair value	$	—		$	—		$	5,592,931		$	(60,200	)	$	5,532,731
	Short-term investments, at fair value	—			—			1,051,074			—			$	1,051,074
	Other investments, at fair value	—			—			881,123			(68,112		)	$	813,011
	Cash and cash equivalents	29,798			81			547,361			—			$	577,240
	Restricted cash	—			—			173,003			—			173,003
	Total investments and cash	29,798			81			8,245,492			(128,312		)	8,147,059
	Investment in affiliates	—			—			261,483			—			261,483
	Investment in subsidiaries on an equity basis	4,140,770			656,738			—			(4,797,508		)	—
	Premiums receivable	—			—			707,647			—			707,647
	Deferred acquisition costs	—			—			161,295			—			161,295
	Prepaid reinsurance premiums	—			—			81,983			—			81,983
	Securities lending collateral	—			—			470			—			470
	Loss reserves recoverable	—			—			377,466			—			377,466
	Paid losses recoverable	—			—			38,078			—			38,078
	Deferred tax asset	—			—			23,821			—			23,821
	Intangible assets	—			—			126,924			—			126,924
	Goodwill	—			—			195,897			—			195,897
	Intercompany receivable	41,078			—			20			(41,098		)	—
	Other assets	3,239			—			186,259			—			189,498
	Total assets	$	4,214,885		$	656,819		$	10,406,835		$	(4,966,918	)	$	10,311,621
	Liabilities
	Reserve for losses and loss expenses	$	—		$	—		$	3,234,394		$	—		$	3,234,394
	Unearned premiums	—			—			990,564			—			990,564
	Reinsurance balances payable	—			—			127,128			—			127,128
	Securities lending payable	—			—			936			—			936
	Deferred tax liability	—			—			5,541			—			5,541
	Net payable for investments purchased	—			—			50,256			—			50,256
	Accounts payable and accrued expenses	29,621			96			288,528			—			318,245
	Intercompany payable	—			20			41,078			(41,098		)	—
	Notes payable to operating affiliates	—			—			671,465			—			671,465
	Senior notes payable	247,306			—			—			—			247,306
	Debentures payable	350,000			—			249,477			(60,200		)	539,277
	Total liabilities	$	626,927		$	116		$	5,659,367		$	(101,298	)	$	6,185,112
	Redeemable noncontrolling interest	—			—			79,956			—			79,956
	Total shareholders' equity available to Validus	3,587,958			656,703			4,208,917			(4,865,620		)	3,587,958
	Noncontrolling interest	—			—			458,595			—			458,595
	Total liabilities, noncontrolling interests and shareholders' equity	$	4,214,885		$	656,819		$	10,406,835		$	(4,966,918	)	$	10,311,621
	(a)	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.
	(b)	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
	Condensed Consolidating Balance Sheet	Validus Holdings, Ltd.			Validus Holdings			Other			Consolidating Adjustments (b)			Validus Holdings, Ltd.
	As at December 31, 2013	(Parent Guarantor)			(UK) plc			Validus Holdings, Ltd.						Consolidated
					(Subsidiary Issuer)			Subsidiaries
								(Non-guarantor Subsidiaries) (a)
	Assets
	Fixed maturities, at fair value	$	—		$	—		$	5,602,458		$	(60,200	)	$	5,542,258
	Short-term investments, at fair value	—			—			787,714			—			787,714
	Other investments, at fair value	—			—			770,116			(66,030		)	704,086
	Cash and cash equivalents	20,385			—			713,763			—			734,148
	Restricted cash	—			—			200,492			—			200,492
	Total investments and cash	$	20,385		$	—		$	8,074,543		$	(126,230	)	$	7,968,698
	Investments in affiliates	—			—			141,243			—			141,243
	Investment in subsidiaries on an equity basis	4,273,592			8,479			—			(4,282,071		)	—
	Premiums receivable	—			—			697,233			—			697,233
	Deferred acquisition costs	—			—			134,269			—			134,269
	Prepaid reinsurance premiums	—			—			103,251			—			103,251
	Securities lending collateral	—			—			3,392			—			3,392
	Loss reserves recoverable	—			—			370,154			—			370,154
	Paid losses recoverable	—			—			80,080			—			80,080
Intangible assets	—			—			106,407			—			106,407
Goodwill	—			—			20,393			—			20,393
Intercompany receivable	29,048			—			100			(29,148		)	—
Other assets	3,767			—			217,545			—			221,312
Total assets	$	4,326,792		$	8,479		$	9,948,610		$	(4,437,449	)	$	9,846,432
Liabilities
Reserve for losses and loss expenses	$	—		$	—		$	3,030,399		$	—		$	3,030,399
Unearned premiums	—			—			824,496			—			824,496
Reinsurance balances payable	—			—			154,874			—			154,874
Securities lending payable	—			—			3,858			—			3,858
Deferred tax liability	—			—			19,086			—			19,086
Net payable for investments purchased	—			—			19,383			—			19,383
Accounts payable and accrued expenses	25,500			—			252,687			—			278,187
Intercompany payable	—			100			29,048			(29,148		)	—
Notes payable to operating affiliates	—			—			439,272			—			439,272
Senior notes payable	247,198			—			—			—			247,198
Debentures payable	350,000			—			251,616			(60,200		)	541,416
Total liabilities	$	622,698		$	100		$	5,024,719		$	(89,348	)	$	5,558,169
Redeemable noncontrolling interest	—			—			86,512			—			86,512
Total shareholders' equity available to Validus	3,704,094			8,379			4,339,722			(4,348,101		)	3,704,094
Noncontrolling interest	—			—			497,657			—			497,657
Total liabilities, noncontrolling interest and shareholders' equity	$	4,326,792		$	8,479		$	9,948,610		$	(4,437,449	)	$	9,846,432
(a)	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.
(b)	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
Condensed consolidating statement of comprehensive income
	Condensed Consolidating	Validus Holdings, Ltd.			Validus Holdings			Other			Consolidating Adjustments (b)			Validus Holdings, Ltd.
	Statement of Comprehensive Income	(Parent Guarantor)			(UK) plc			Validus Holdings, Ltd.						Consolidated
	For the Year Ended December 31, 2014				(Subsidiary Issuer)			Subsidiaries
								(Non-guarantor Subsidiaries) (a)
	Revenues
	Net premiums earned	$	—		$	—		$	2,002,404		$	—		$	2,002,404
	Net investment income	14			—			103,972			(3,910		)	100,076
	Net realized gains on investments	—			—			23,095			—			23,095
	Change in net unrealized losses on investments	—			—			(55,891		)	(2,082		)	(57,973		)
	Income from investment affiliate	—			—			8,411			—			8,411
	Other insurance related income and other income	—			—			86,906			(67,167		)	19,739
	Foreign exchange gains (losses)	648			1			(11,279		)	—			(10,630		)
	Total revenues	$	662		$	1		$	2,157,618		$	(73,159	)	$	2,085,122
	Expenses
	Losses and loss expenses	—			—			772,049			—			772,049
	Policy acquisition costs	—			—			340,556			—			340,556
	General and administrative expenses	86,108			117			310,734			(67,167		)	329,792
	Share compensation expenses	6,424			—			26,649			—			33,073
	Finance expenses	47,689			—			18,109			(1,944		)	63,854
	Transaction expenses	—			—			8,096			—			8,096
	Total expenses	$	140,221		$	117		$	1,476,193		$	(69,111	)	$	1,547,420
	(Loss) income before taxes, income from operating affiliates, (income) attributable to operating affiliate investors and equity in net earnings of subsidiaries	(139,559		)	(116		)	681,425			(4,048		)	537,702
	Tax expense	—			—			(155		)	—			(155		)
	Income from operating affiliates	—			—			17,723			—			17,723
	(Income) attributable to operating affiliate investors	—			—			(109,399		)	—			(109,399		)
	Equity in net earnings of subsidiaries	620,894			1,940			—			(622,834		)	—
	Net income (loss)	$	481,335		$	1,824		$	589,594		$	(626,882	)	$	445,871
	Net loss attributable to noncontrolling interest	—			—			35,464			—			35,464
	Net income (loss) available (attributable) to Validus	$	481,335		$	1,824		$	625,058		$	(626,882	)	$	481,335
	Other comprehensive (loss) income	(7,939		)	—			(7,711		)	7,711			(7,939		)
	Comprehensive income (loss) available (attributable) to Validus	$	473,396		$	1,824		$	617,347		$	(619,171	)	$	473,396
	(a)	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.
	(b)	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
	Condensed Consolidating	Validus Holdings, Ltd.			Validus Holdings			Other			Consolidating Adjustments (b)			Validus Holdings, Ltd.
	Statement of Comprehensive Income	(Parent Guarantor)			(UK) plc			Validus Holdings, Ltd.						Consolidated
	For the Year Ended December 31, 2013				(Subsidiary Issuer)			Subsidiaries
								(Non-guarantor Subsidiaries) (a)
	Revenues
	Net premiums earned	$	—		$	—		$	2,102,045		$	—		$	2,102,045
	Net investment income	14			—			103,272			(7,214		)	96,072
	Net realized gains on investments	—			—			3,258			—			3,258
	Change in net unrealized losses on investments	—			—			(49,599		)	(8,882		)	(58,481		)
	Income from investment affiliate	—			—			4,790			—			4,790
	Other insurance related income and other income	36			—			75,425			(67,118		)	8,343
	Foreign exchange (losses) gains	(382		)	—			2,887			—			2,505
	Total revenues	$	(332	)	$	—		$	2,242,078		$	(83,214	)	$	2,158,532
	Expenses
	Losses and loss expenses	—			—			793,932			—			793,932
	Policy acquisition costs	—			—			360,310			—			360,310
	General and administrative expenses	84,143			—			298,240			(67,118		)	315,265
	Share compensation expenses	6,329			—			21,301			—			27,630
	Finance expenses	45,868			—			20,278			(1,969		)	64,177
	Total expenses	$	136,340		$	—		$	1,494,061		$	(69,087	)	$	1,561,314
	(Loss) income before taxes, income from operating affiliates, (income) attributable to operating affiliate investors and equity in net earnings (losses) of subsidiaries	(136,672		)	—			748,017			(14,127		)	597,218
	Tax expense	—			—			(383		)	—			(383		)
	Income from operating affiliates	—			—			14,289			—			14,289
	(Income) attributable to operating affiliate investors	—			—			(68,763		)	—			(68,763		)
	Equity in net earnings (losses) of subsidiaries	669,338			(5,938		)	—			(663,400		)	—
	Net income (loss)	$	532,666		$	(5,938	)	$	693,160		$	(677,527	)	$	542,361
	Net income attributable to noncontrolling interest	—			—			(9,695		)	—			(9,695		)
	Net income (loss) available (attributable) to Validus	$	532,666		$	(5,938	)	$	683,465		$	(677,527	)	$	532,666
	Other comprehensive (loss) income	(1,954		)	—			(1,954		)	1,954			(1,954		)
	Comprehensive income (loss) available (attributable) to Validus	$	530,712		$	(5,938	)	$	681,511		$	(675,573	)	$	530,712
(a)	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.
(b)	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
Condensed Consolidating	Validus Holdings, Ltd.			Validus Holdings			Other			Consolidating Adjustments (b)			Validus Holdings, Ltd.
Statement of Comprehensive Income	(Parent Guarantor)			(UK) plc			Validus Holdings, Ltd.						Consolidated
For the Year Ended December 31, 2012				(Subsidiary Issuer)			Subsidiaries
							(Non-guarantor Subsidiaries) (a)
Revenue
Net premiums earned	$	—		$	—		$	1,873,216		$	—		$	1,873,216
Gain on bargain purchase, net of expenses	—			—			17,701			—			17,701
Net investment income	3			—			113,375			(5,442		)	107,936
Net realized gains on investments	—			—			18,233			—			18,233
Change in net unrealized gains on investments	—			—			17,585			—			17,585
Loss from investment affiliate	—			—			(964		)	—			(964		)
Other insurance related income and other income	—			—			37,022			(14,626		)	22,396
Foreign exchange (losses) gains	(469		)	—			5,267			—			4,798
Total revenue	$	(466	)	$	—		$	2,081,435		$	(20,068	)	$	2,060,901
Expenses
Losses and loss expenses	—			—			999,446			—			999,446
Policy acquisition costs	—			—			334,698			—			334,698
General and administrative expenses	66,576			—			211,702			(14,626		)	263,652
Share compensation expenses	8,503			—			18,206			—			26,709
Finance expenses	45,203			—			12,186			(3,532		)	53,857
Total expenses	$	120,282		$	—		$	1,576,238		$	(18,158	)	$	1,678,362
(Loss) income before taxes, income from operating affiliates and equity in net earnings (losses) of subsidiaries	(120,748		)	—			505,197			(1,910		)	382,539
Tax expense	—			—			(2,501		)	—			(2,501		)
Income from operating affiliates	—			—			12,580			—			12,580
Equity in net earnings (losses) of subsidiaries	529,186			(1,306		)	—			(527,880		)	—
Net income (loss)	$	408,438		$	(1,306	)	$	515,276		$	(529,790	)	$	392,618
Net loss attributable to noncontrolling interest	—			—			15,820			—			15,820
Net income (loss) available (attributable) to Validus	$	408,438		$	(1,306	)	$	531,096		$	(529,790	)	$	408,438
Other comprehensive income (loss)	3,648			—			3,648			(3,648		)	3,648
Comprehensive income (loss) available (attributable) to Validus	$	412,086		$	(1,306	)	$	534,744		$	(533,438	)	$	412,086
(a)	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.
(b)	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
Condensed consolidating statement of cash flows
	Condensed Consolidating Statement of Cash Flows	Validus Holdings, Ltd.			Validus Holdings			Other			Consolidating Adjustments (b)			Validus Holdings, Ltd.
	For the Year Ended December 31, 2014	(Parent Guarantor)			(UK) plc			Validus Holdings, Ltd.						Consolidated
					(Subsidiary Issuer)			Subsidiaries
								(Non-guarantor Subsidiaries) (a)
	Net cash (used in) provided by operating activities	$	(41,905	)	$	81		$	383,605		$	(100,000	)	$	241,781
	Cash flows provided by (used in) investing activities
	Proceeds on sales of investments	—			—			4,756,555			—			4,756,555
	Proceeds on maturities of investments	—			—			554,619			—			554,619
	Purchases of fixed maturities	—			—			(4,379,314		)	—			(4,379,314		)
	Purchases of short-term investments, net	—			—			(121,264		)	—			(121,264		)
	Purchases of other investments	—			—			(119,815		)	—			(119,815		)
	Decrease in securities lending collateral	—			—			2,922			—			2,922
	Investment in operating affiliates	—			—			(37,600		)	—			(37,600		)
	Redemption from operating affiliates	—			—			77,544			—			77,544
	Investment in investment affiliates	—			—			(12,468		)	—			(12,468		)
	Decrease in restricted cash	—			—			27,489			—			27,489
	Proceeds on sale of subsidiary, net of cash	—			—			16,459			—			16,459
	Purchase of subsidiary, net of cash acquired	—			—			(643,545		)	—			(643,545		)
	Return of capital from subsidiaries	673,966			—			—			(673,966		)	—
	Investment in subsidiaries	—			(240,000		)	(240,000		)	480,000			—
	Net cash provided by (used in) investing activities	673,966			(240,000		)	(118,418		)	(193,966		)	121,582
	Cash flows provided by (used in) financing activities
	Proceeds on issuance of notes payable to operating affiliates	—			—			680,027			—			680,027
	Repayments on notes payable to operating affiliates	—			—			(617,068		)	—			(617,068		)
	Issuance of common shares, net	5,347			—			—			—			5,347
	Purchases of common shares under share repurchase program	(510,952		)	—			—			—			(510,952		)
	Dividends paid	(117,043		)	—			(100,000		)	100,000			(117,043		)
	Decrease in securities lending payable	—			—			(2,922		)	—			(2,922		)
	Third party investment in redeemable noncontrolling interest	—			—			68,200			—			68,200
	Third party redemption of redeemable noncontrolling interest	—			—			(10,496		)	—			(10,496		)
	Third party subscriptions received in advance	—			—			15,400			—			15,400
	Return of capital to parent	—			—			(673,966		)	673,966			—
	Capital contribution from parent	—			240,000			240,000			(480,000		)	—
	Net cash (used in) provided by financing activities	(622,648		)	240,000			(400,825		)	293,966			(489,507		)
	Effect of foreign currency rate changes on cash and cash equivalents	—			—			(30,764		)	—			(30,764		)
	Net increase (decrease) in cash	9,413			81			(166,402		)	—			(156,908		)
	Cash and cash equivalents, beginning of year	20,385			—			713,763			—			734,148
	Cash and cash equivalents, end of year	$	29,798		$	81		$	547,361		$	—		$	577,240
	(a)	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.
	(b)	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
	Condensed Consolidating Statement of Cash Flows	Validus Holdings, Ltd.			Validus Holdings			Other			Consolidating Adjustments (b)			Validus Holdings, Ltd.
	For the Year Ended December 31, 2013	(Parent Guarantor)			(UK) plc			Validus Holdings, Ltd.						Consolidated
					(Subsidiary Issuer)			Subsidiaries
								(Non-guarantor Subsidiaries) (a)
	Net cash provided by (used in) operating activities	$	873,083		$	—		$	401,191		$	(1,009,000	)	$	265,274
	Cash flows provided by (used in) investing activities
	Proceeds on sales of investments	—			—			4,370,548			—			4,370,548
	Proceeds on maturities of investments	—			—			490,459			—			490,459
	Purchases of fixed maturities	—			—			(5,392,728		)	—			(5,392,728		)
	Sales of short-term investments, net	—			—			353,353			—			353,353
	Purchases of other investments	—			—			(38,492		)	—			(38,492		)
	Increase in securities lending collateral	—			—			(3,167		)	—			(3,167		)
	Investment in operating affiliates	—			—			(22,000		)	—			(22,000		)
	Redemption from operating affiliates	—			—			86,657			—			86,657
	Investment in investment affiliates	—			—			(14,492		)	—			(14,492		)
	Increase in restricted cash	—			—			(172,962		)	—			(172,962		)
	Proceeds on sale of subsidiary, net of cash	—			—			21,388			—			21,388
	Net cash used in investing activities	—			—			(321,436		)	—			(321,436		)
	Cash flows provided by (used in) financing activities
	Proceeds on issuance of notes payable to operating affiliates	—			—			442,412			—			442,412
	Repayments on notes payable to operating affiliates	—			—			(3,553		)	—			(3,553		)
	Issuance of common shares, net	1,211			—			—			—			1,211
	Purchases of common shares under share repurchase program	(513,504		)	—			—			—			(513,504		)
Dividends paid	(360,071		)	—			(1,009,000		)	1,009,000			(360,071		)
Increase in securities lending payable	—			—			3,167			—			3,167
Third party investment in redeemable noncontrolling interest	—			—			92,190			—			92,190
Third party redemption of redeemable noncontrolling interest	—			—			(19,400		)	—			(19,400		)
Investment in third party noncontrolling interest	—			—			58,500			—			58,500
Third party subscriptions received in advance	—			—			35,000			—			35,000
Net cash (used in) provided by financing activities	(872,364		)	—			(400,684		)	1,009,000			(264,048		)
Effect of foreign currency rate changes on cash and cash equivalents	—			—			(6,364		)	—			(6,364		)
Net increase (decrease) in cash	719			—			(327,293		)	—			(326,574		)
Cash and cash equivalents, beginning of year	19,666			—			1,041,056			—			1,060,722
Cash and cash equivalents, end of year	$	20,385		$	—		$	713,763		$	—		$	734,148
(a)	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.
(b)	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
Condensed Consolidating Statement of Cash Flows	Validus Holdings, Ltd.			Validus Holdings			Other			Consolidating Adjustments (b)			Validus Holdings, Ltd.
For the Year Ended December 31, 2012	(Parent Guarantor)			(UK) plc			Validus Holdings, Ltd.						Consolidated
				(Subsidiary Issuer)			Subsidiaries
							(Non-guarantor Subsidiaries) (a)
Net cash provided by (used in) operating activities	$	548,288		$	—		$	728,877		$	(734,000	)	$	543,165
Cash flows provided by (used in) investing activities
Proceeds on sales of investments	—			—			3,393,740			—			3,393,740
Proceeds on maturities of investments	—			—			548,226			—			548,226
Purchases of fixed maturities	—			—			(3,726,611		)	—			(3,726,611		)
Sales of short-term investments, net	—			—			56,502			—			56,502
Purchases of other investments	—			—			(491,210		)	—			(491,210		)
Decrease in securities lending collateral	—			—			7,771			—			7,771
Investment in operating affiliates	—			—			(91,500		)	—			(91,500		)
Investment in investment affiliates	—			—			(12,835		)	—			(12,835		)
Increase in restricted cash	—			—			(3,493		)	—			(3,493		)
Purchase of subsidiary, net of cash acquired	—			—			17,196			—			17,196
Investment in subsidiaries	(166,582		)	—			—			166,582			—
Net cash (used in) provided by investing activities	(166,582		)	—			(302,214		)	166,582			(302,214		)
Cash flows provided by (used in) financing activities
Issuance of common shares, net	3,015			—			—			—			3,015
Purchases of common shares under share repurchase program	(259,962		)	—			—			—			(259,962		)
Dividends paid	(110,037		)	—			(734,000		)	734,000			(110,037		)
Decrease in securities lending payable	—			—			(7,771		)	—			(7,771		)
Investment in third party noncontrolling interest	—			—			450,100			—			450,100
Third party subscriptions received in advance	—			—			19,400			—			19,400
Capital contribution from parent	—			—			166,582			(166,582		)	—
Net cash (used in) provided by financing activities	(366,984		)	—			(105,689		)	567,418			94,745
Effect of foreign currency rate changes on cash and cash equivalents	—			—			17,540			—			17,540
Net increase in cash	14,722			—			338,514			—			353,236
Cash and cash equivalents, beginning of year	4,944			—			702,542			—			707,486
Cash and cash equivalents, end of year	$	19,666		$	—		$	1,041,056		$	—		$	1,060,722
(a)	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.
(b)	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.

Nature_of_the_business_Details

Nature of the business (Details) (USD $)	12 Months Ended	0 Months Ended	1 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Nov. 30, 2012	Oct. 31, 2013
	segments
Nature Of Business [Line Items]
Number of operating segments	4
Flagstone Reinsurance Holdings Sa
Nature Of Business [Line Items]
Exchange ratio		0.1935
Per share price paid by Company to acquire FSR common shares		2
Flagstone Alliance Insurance and Reinsurance Plc [Member]
Nature Of Business [Line Items]
Proceeds from Divestiture of Interest in Consolidated Subsidiaries			$21,400

Basis_of_preparation_and_conso1

Basis of preparation and consolidation (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Reclassification to reduce cash and cash equivalents
Significant Accounting Policies [Line Items]
Prior period reclassification adjustment	$322,198
Reclassification from cash and cash equivalents to restricted cash
Significant Accounting Policies [Line Items]
Prior period reclassification adjustment	-200,492
Reclassification from cash and cash equivalents to short-term investments
Significant Accounting Policies [Line Items]
Prior period reclassification adjustment	-35,936
Reclassification from cash and cash equivalents to other investments
Significant Accounting Policies [Line Items]
Prior period reclassification adjustment	-85,770
Increase (decrease) net cash (used in) investing activities
Significant Accounting Policies [Line Items]
Prior period reclassification adjustment	163,541	33,299
Net (decrease) in cash
Significant Accounting Policies [Line Items]
Prior period reclassification adjustment	($163,541)	($33,299)

Significant_accounting_policie2

Significant accounting policies (Details)	12 Months Ended
	Dec. 31, 2014
Premiums
Significant Accounting Policies [Line Items]
Assumed risk period, in months	24 months
Derivative | Maximum
Significant Accounting Policies [Line Items]
Hedge effectiveness criteria, percent	125.00%
Derivative | Minimum
Significant Accounting Policies [Line Items]
Hedge effectiveness criteria, percent	80.00%
Cash and cash equivalents
Significant Accounting Policies [Line Items]
Time period for recognition, as shown	1 month

Business_combination_Acquisiti

Business combination (Acquisition details) (Details) (USD $)	12 Months Ended			0 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Oct. 02, 2014	Nov. 30, 2012
Liabilities acquired
Bargain purchase gain on acquisition of Flagstone	$0	$0	$49,702
Goodwill	195,897	20,393	20,393
Western World Insurance Group, Inc
Total allocable purchase price
Total allocable purchase price				692,305
Tangible assets acquired
Cash and cash equivalents				48,760
Investments				1,126,185
Receivables				37,848
Other assets				19,418
Tangible assets acquired				1,232,211
Intangible assets acquired
Intangible assets acquired				25,055
Liabilities acquired
Net loss reserves and paid losses recoverable				523,315
Unearned premiums, net of expenses				135,686
Other liabilities				81,464
Liabilities acquired				740,465
Goodwill				175,504
Flagstone Reinsurance Holdings Sa
Total allocable purchase price
Flagstone shares outstanding at November 30, 2012					73,852,137
Exchange ratio					0.1935
Validus common shares issued, gross of taxes withheld					14,290,389
Validus closing share price at acquisition					$34.87
Total value of Validus shares issued					498,306
Total cash consideration paid at $2.00 per Flagstone share					147,731
Total allocable purchase price					646,037
Tangible assets acquired
Cash and cash equivalents					159,339
Investments					1,323,002
Receivables					171,620	[1]
Other assets					129,245
Tangible assets acquired					1,783,206
Liabilities acquired
Net loss reserves and paid losses recoverable					639,641
Unearned premiums, net of expenses					104,592
Debentures payable					250,657
Other liabilities					98,574
Liabilities acquired					1,093,464
Net tangible assets acquired, at fair value					689,742
Bargain purchase gain before establishment of intangible assets					43,705
Intangible asset - customer relationships and brand name					5,997
Bargain purchase gain on acquisition of Flagstone			49,702		49,702
State licenses | Western World Insurance Group, Inc
Intangible assets acquired
Intangible asset - indefinite-lived				12,325
Brand names | Western World Insurance Group, Inc
Intangible assets acquired
Intangible asset - finite-lived				5,756
Brand names | Flagstone Reinsurance Holdings Sa
Liabilities acquired
Intangible asset - customer relationships and brand name					3,402
Distribution network | Western World Insurance Group, Inc
Intangible assets acquired
Intangible asset - finite-lived				4,651
Technology | Western World Insurance Group, Inc
Intangible assets acquired
Intangible asset - finite-lived				$2,323
[1]	Premiums receivable of $171,620 were net of an allowance for doubtful accounts of $2,216.

Business_combination_Component

Business combination (Components of gain on bargain purchase) (Details) (USD $)	3 Months Ended												12 Months Ended					0 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2012		Sep. 30, 2012		Jun. 30, 2012		Mar. 31, 2012		Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012		Nov. 30, 2012
Business Acquisition [Line Items]
Bargain purchase gain on acquisition of Flagstone													$0		$0	$49,702
Transaction expenses	-4,695	-149	-3,252	0									-8,096	[1]	0	0
Amortization of intangible asset—customer relationships and brand name													-4,538		-4,162	-10,159
Gain on bargain purchase, net of expenses					21,485	[2]	-3,784	[2]	0	[2]	0	[2]	0		0	17,701	[2]
Flagstone Reinsurance Holdings Sa
Business Acquisition [Line Items]
Bargain purchase gain on acquisition of Flagstone																49,702		49,702
Transaction expenses																-5,760
Termination expenses																-20,244
Amortization of intangible asset—customer relationships and brand name																-5,997
Gain on bargain purchase, net of expenses																$17,701
[1]	The transaction expenses relate to costs incurred in connection with the acquisition of Western World, which was completed on October 2, 2014. Transaction expenses are primarily comprised of legal, financial advisory and audit related services.
[2]	The gain on bargain purchase, net of expenses, arose from the acquisition of Flagstone Reinsurance Holdings S.A. on November 30, 2012 and is net of transaction related expenses which included legal, financial advisory, audit related services and termination expenses.

Business_combination_Pro_forma

Business combination (Pro forma information) (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, 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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues
Income (loss) from investment affiliate	$530	$1,754	$779	$5,348	$516	$1,044	$1,753	$1,477	($406)	($160)	($398)	$0	$8,411	$4,790	($964)
Expenses
Income from operating affiliates	4,143	3,761	4,892	4,927	5,510	1,463	3,793	3,523	-614	6,235	3,592	3,367	17,723	14,289	12,580
Western World Insurance Group, Inc
Revenues
Net premiums earned													2,216,349	2,325,407
Expenses
Net income (loss) from continuing operations													481,179	645,696
Net income (loss) available (attributable) to Validus													448,071	561,832
Flagstone Reinsurance Holdings Sa
Revenues
Gross premiums written															2,536,535	2,914,388
Reinsurance premiums ceded															-397,008	-520,506
Net premiums written															2,139,527	2,393,882
Change in unearned premiums															86,935	-20,261
Net premiums earned															2,226,462	2,373,621
Net investment income															126,140	143,472
Net realized gains on investments															63,601	37,366
Net unrealized gains (losses) on investments															5,654	-47,101
Income (loss) from investment affiliate															-964	0
Other income															29,984	11,152
Foreign exchange gains (losses)															1,363	-26,605
Total revenues															2,452,240	2,491,905
Expenses
Losses and loss expenses															1,242,449	1,920,936
Policy acquisition costs															413,579	429,509
General and administrative expenses															323,061	282,183
Share compensation expenses															30,750	35,427
Transaction expenses															0	17,433
Finance expenses															64,306	66,485
Total expenses															2,074,145	2,751,973
Net income before taxes															378,095	-260,068
Tax (expense)															-3,385	-773
Income from operating affiliates															12,868	-922
Net income (loss) from continuing operations															387,578	-261,763
Net income (loss) from discontinued operations, net of taxes															19,366	-21,662
Net income (loss)															406,944	-283,425
Net (loss) income attributable to noncontrolling interest															14,685	-24,515
Net income (loss) available (attributable) to Validus															$421,629	($307,940)
Basic earnings per share															$3.73	($3.20)
Diluted earnings per share															$3.62	($3.20)

Business_combination_Results_s

Business combination (Results since acquisition) (Details) (USD $)	3 Months Ended	1 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2012
Western World Insurance Group, Inc
Business Acquisition [Line Items]
Net premiums written	$58,807
Total revenue	78,325
Total expenses	-66,882
Net income	11,443
Flagstone Reinsurance Holdings Sa
Business Acquisition [Line Items]
Net premiums written		11,305
Total revenue		26,778
Total expenses		-17,061
Net income		$9,717

Business_combination_Narrative

Business combination (Narrative) (Details) (USD $)	0 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Oct. 02, 2014	Nov. 30, 2012
Western World Insurance Group, Inc
Business Acquisition [Line Items]
Aggregate purchase price	$692,305
Acquired premiums receivable	37,848
Flagstone Reinsurance Holdings Sa
Business Acquisition [Line Items]
Exchange ratio		0.1935
Per share price paid by Company to acquire FSR common shares		$2
Aggregate purchase price		646,037
Net tangible assets acquired, at fair value		689,742
Intangible asset - customer relationships and brand name		5,997
Acquired premiums receivable		171,620	[1]
Allowance for doubtful accounts on premiums receivable		2,216
Flagstone Reinsurance Holdings Sa | Customer relationships [Member]
Business Acquisition [Line Items]
Intangible asset - customer relationships and brand name		2,595
Flagstone Reinsurance Holdings Sa | Brand names
Business Acquisition [Line Items]
Intangible asset - customer relationships and brand name		$3,402
[1]	Premiums receivable of $171,620 were net of an allowance for doubtful accounts of $2,216.

Goodwill_and_other_intangible_2

Goodwill and other intangible assets (Analysis of goodwill) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Goodwill [Line Items]
Goodwill, beginning of year	$20,393	$20,393
Acquired during the year	175,504	0
Goodwill, end of year	195,897	20,393
Talbot
Goodwill [Line Items]
Goodwill, beginning of year	20,393	20,393
Acquired during the year	0	0
Goodwill, end of year	20,393	20,393
Western World
Goodwill [Line Items]
Goodwill, beginning of year	0	0
Acquired during the year	175,504	0
Goodwill, end of year	$175,504	$0

Goodwill_and_other_intangible_3

Goodwill and other intangible assets (Analysis of carrying value and accumulated amortization of intangible assets) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Goodwill And Other Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount	$60,343	$47,613
Finite-lived intangible assets, accumulated amortization	-37,587	-33,049
Indefinite-lived intangible assets	104,168	91,843
Trade name and customer relationships
Goodwill And Other Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount	18,189	12,433
Finite-lived intangible assets, accumulated amortization	-10,971	-10,183
Distribution network
Goodwill And Other Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount	39,831	35,180
Finite-lived intangible assets, accumulated amortization	-26,500	-22,866
Technology
Goodwill And Other Intangible Assets [Line Items]
Finite-lived intangible assets, gross carrying amount	2,323	0
Finite-lived intangible assets, accumulated amortization	-116	0
Syndicate capacity
Goodwill And Other Intangible Assets [Line Items]
Indefinite-lived intangible assets	91,843	91,843
State licenses
Goodwill And Other Intangible Assets [Line Items]
Indefinite-lived intangible assets	$12,325	$0

Goodwill_and_other_intangible_4

Goodwill and other intangible assets (Future amortization expense) (Details) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Goodwill and Intangible Assets Disclosure [Abstract]
2015	$5,663
2016	5,663
2017	3,579
2018	1,501
2019 and thereafter	6,350
Intangible assets with a finite life, net	$22,756

Goodwill_and_other_intangible_5

Goodwill and other intangible assets (Narrative) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Nov. 30, 2012
Business Acquisition [Line Items]
Amortization of intangible assets	$4,538	$4,162	$10,159
Flagstone Reinsurance Holdings Sa
Business Acquisition [Line Items]
Amortization of intangible assets			5,997
Intangible asset - customer relationships and brand name				5,997
Talbot
Business Acquisition [Line Items]
Percentage ownership of syndicated capacity	100.00%
Brand names | Western World Insurance Group, Inc
Business Acquisition [Line Items]
Useful lives of acquired intangible assets	10 years
Brand names | Flagstone Reinsurance Holdings Sa
Business Acquisition [Line Items]
Intangible asset - customer relationships and brand name				$3,402
Technology | Western World Insurance Group, Inc
Business Acquisition [Line Items]
Useful lives of acquired intangible assets	5 years
Distribution network | Western World Insurance Group, Inc
Business Acquisition [Line Items]
Useful lives of acquired intangible assets	10 years
Distribution network | Talbot
Business Acquisition [Line Items]
Useful lives of acquired intangible assets	10 years
Trademark | Talbot
Business Acquisition [Line Items]
Useful lives of acquired intangible assets	10 years

Investments_Gross_unrealized_g

Investments (Gross unrealized gains and losses on fixed maturities) (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Fixed maturities, at amortized cost	$5,534,494		$5,522,853
Short-term investments, at amortized cost	1,051,222		787,670
Other investments, at amortized cost	879,176		723,498
Amortized cost	7,464,892		7,034,021
Catastrophe bonds, cost	-75,822		-53,000
Noncontrolling interest, cost or amortized cost	-502,830	[1]	-512,121	[1]
Total investments excluding non-controlling interest, cost or amortized cost	6,153,458		5,817,185
Fixed maturities, gross unrealized gains	24,357		42,756
Short term investments, gross unrealized gains	13	[2]	45	[3]
Other investments, gross unrealized gains	69,881		76,843
Gross unrealized gains	94,251		119,644
Unrealized gains on catastrophe bonds	-768		-2,544
Noncontrolling interest share of unrealized gains other investments	-48,446	[1]	-62,850	[1]
Total investments excluding non-controlling interest, unrealized gains	45,037		54,250
Fixed maturities, gross unrealized losses	-26,120		-23,351
Short term investments, gross unrealized losses	-161	[2]	-1	[3]
Other investments, gross unrealized losses	-136,046		-96,255
Gross unrealized losses	-162,327		-119,607
Unrealized losses on catastrophe bonds	926		0
Noncontrolling interest share of unrealized losses	120,782	[1]	85,569	[1]
Total investments excluding non-controlling interest, unrealized losses	-40,619		-34,038
Total fixed maturities	5,532,731		5,542,258
Short term investments at fair value	1,051,074		787,714
Other investments	813,011		704,086
Total investments including assets held in trust, catastrophe bonds and noncontrolling interest	7,396,816		7,034,058
Assets held in trust on behalf of operating affiliates	-732,782	[2]	-651,715	[3]
Catastrophe bonds, fair value	-75,664		-55,544
Noncontrolling interest	-430,494	[1]	-489,402	[1]
Total investments excluding noncontrolling interest	6,157,876		5,837,397
U.S. government and government agency
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Fixed maturities, at amortized cost	759,232		1,368,826
Fixed maturities, gross unrealized gains	1,755		2,589
Fixed maturities, gross unrealized losses	-901		-6,736
Total fixed maturities	760,086		1,364,679
Non-U.S. government and government agency
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Fixed maturities, at amortized cost	279,493		454,578
Fixed maturities, gross unrealized gains	1,215		6,511
Fixed maturities, gross unrealized losses	-1,980		-2,021
Total fixed maturities	278,728		459,068
U.S. states, municipalities and political subdivisions
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Fixed maturities, at amortized cost	448,668		42,978
Fixed maturities, gross unrealized gains	1,780		459
Fixed maturities, gross unrealized losses	-825		-317
Total fixed maturities	449,623		43,120
Agency residential mortgage-backed securities
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Fixed maturities, at amortized cost	520,685		305,450
Fixed maturities, gross unrealized gains	9,697		8,310
Fixed maturities, gross unrealized losses	-1,151		-2,261
Total fixed maturities	529,231		311,499
Non-agency residential mortgage-backed securities
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Fixed maturities, at amortized cost	37,954		16,530
Fixed maturities, gross unrealized gains	369		143
Fixed maturities, gross unrealized losses	-516		-914
Total fixed maturities	37,807		15,759
U.S. corporate
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Fixed maturities, at amortized cost	1,500,963		1,328,960
Fixed maturities, gross unrealized gains	3,960		9,208
Fixed maturities, gross unrealized losses	-5,217		-5,684
Total fixed maturities	1,499,706		1,332,484
Non-U.S. corporate
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Fixed maturities, at amortized cost	564,386		711,581
Fixed maturities, gross unrealized gains	2,765		5,917
Fixed maturities, gross unrealized losses	-3,989		-3,173
Total fixed maturities	563,162		714,325
Bank loans
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Fixed maturities, at amortized cost	457,537		712,859
Fixed maturities, gross unrealized gains	200		5,659
Fixed maturities, gross unrealized losses	-8,733		-1,402
Total fixed maturities	449,004		717,116
Catastrophe bonds
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Fixed maturities, at amortized cost	75,822		72,000
Fixed maturities, gross unrealized gains	768		2,551
Fixed maturities, gross unrealized losses	-926		0
Total fixed maturities	75,664		74,551
Asset-backed securities
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Fixed maturities, at amortized cost	647,422		509,091
Fixed maturities, gross unrealized gains	1,250		1,409
Fixed maturities, gross unrealized losses	-1,190		-843
Total fixed maturities	647,482		509,657
Commercial mortgage backed securities
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Fixed maturities, at amortized cost	242,332
Fixed maturities, gross unrealized gains	598
Fixed maturities, gross unrealized losses	-692
Total fixed maturities	242,238
Fund of hedge funds
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Other investments, at amortized cost	2,570		3,141
Other investments, gross unrealized gains	125		83
Other investments, gross unrealized losses	-920		-921
Other investments	1,775		2,303
Preferred stock
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Other investments, at amortized cost	6,535
Other investments, gross unrealized gains	0
Other investments, gross unrealized losses	-201
Other investments	6,334
Hedge funds
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Other investments, at amortized cost	570,371	[1]	584,518	[1]
Other investments, gross unrealized gains	60,792	[1]	71,641	[1]
Other investments, gross unrealized losses	-134,203	[1]	-95,076	[1]
Other investments	496,960	[1]	561,083	[1]
Private equity investments
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Other investments, at amortized cost	48,995		12,333
Other investments, gross unrealized gains	4,987		1,410
Other investments, gross unrealized losses	-611		-258
Other investments	53,371		13,485
Investment funds
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Other investments, at amortized cost	244,506		117,307
Other investments, gross unrealized gains	437		92
Other investments, gross unrealized losses	-111		0
Other investments	244,832		117,399
Mutual funds
Amortized cost, gross unrealized gains and (losses) and estimated fair value of investments
Other investments, at amortized cost	6,199		6,199
Other investments, gross unrealized gains	3,540		3,617
Other investments, gross unrealized losses	0		0
Other investments	$9,739		$9,816
PaCRe Funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Company's equity interest in PacRe (percent)	10.00%		10.00%
Noncontrolling interest, equity in PacRe (percent)	90.00%		90.00%
[1]	Included in the hedge funds balance are investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and included in the Consolidated Balance Sheets as noncontrolling interest.
[2]	Included in the short-term investments balance are assets held in trust to support AlphaCat's fully collateralized reinsurance transactions. Also, included in the short-term investments balance are investments held by one AlphaCat ILS fund which is consolidated by the Company but in which the Company has an equity interest of less than 100%. The remaining interests are held by third party investors and included in the Consolidated Balance Sheets as redeemable noncontrolling interest.
[3]	Included in the short-term investments balance are assets held in trust to support AlphaCat's fully collateralized reinsurance transactions. Also, included in the short-term investments balance are investments held by two AlphaCat ILS funds which are consolidated by the Company but in which the Company has an equity interest of less than 100%. The remaining interests are held by third party investors and included in the Consolidated Balance Sheets as redeemable noncontrolling interest.

Investments_Fixed_maturities_b

Investments (Fixed maturities by investment rating) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fixed Maturities
Estimated fair value	$5,532,731	$5,542,258
Percentage of total	100.00%	100.00%
Investment Grade [Member]
Fixed Maturities
Estimated fair value	4,933,764	4,764,580
Percentage of total	89.20%	86.00%
Investment Grade [Member] | AAA [Member]
Fixed Maturities
Estimated fair value	2,494,239	2,510,781
Percentage of total	45.10%	45.30%
Investment Grade [Member] | AA [Member]
Fixed Maturities
Estimated fair value	848,226	696,998
Percentage of total	15.40%	12.60%
Investment Grade [Member] | A [Member]
Fixed Maturities
Estimated fair value	1,086,091	1,233,716
Percentage of total	19.60%	22.30%
Investment Grade [Member] | BBB [Member]
Fixed Maturities
Estimated fair value	505,208	323,085
Percentage of total	9.10%	5.80%
Non-Investment Grade [Member]
Fixed Maturities
Estimated fair value	598,967	777,678
Percentage of total	10.80%	14.00%
Non-Investment Grade [Member] | BB [Member]
Fixed Maturities
Estimated fair value	362,972	354,992
Percentage of total	6.60%	6.40%
Non-Investment Grade [Member] | B [Member]
Fixed Maturities
Estimated fair value	145,240	383,639
Percentage of total	2.60%	6.90%
Non-Investment Grade [Member] | CCC [Member]
Fixed Maturities
Estimated fair value	12,733	2,453
Percentage of total	0.20%	0.00%
Non-Investment Grade [Member] | CC [Member]
Fixed Maturities
Estimated fair value	3,926	2,496
Percentage of total	0.10%	0.10%
Non-Investment Grade [Member] | Standard & Poor's, C Rating [Member]
Fixed Maturities
Estimated fair value	1,344	235
Percentage of total	0.00%	0.00%
Non-Investment Grade [Member] | D/NR [Member]
Fixed Maturities
Estimated fair value	$72,752	$33,863
Percentage of total	1.30%	0.60%

Investments_Maturity_profile_o

Investments (Maturity profile of fixed maturity investments) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Maturity profile
Amortized cost	$5,534,494	$5,522,853
Estimated fair value	5,532,731	5,542,258
Fixed maturities trading securities allocated to contractual maturity [Member]
Maturity profile
Amortized cost	4,086,101	4,691,782
Estimated fair value	4,075,973	4,705,343
Due in one year or less [Member] | Fixed maturities trading securities allocated to contractual maturity [Member]
Maturity profile
Amortized cost	312,843	688,855
Estimated fair value	313,248	692,768
Due after one year through five years [Member] | Fixed maturities trading securities allocated to contractual maturity [Member]
Maturity profile
Amortized cost	3,163,225	3,603,459
Estimated fair value	3,159,200	3,613,847
Due after five years through ten years [Member] | Fixed maturities trading securities allocated to contractual maturity [Member]
Maturity profile
Amortized cost	497,175	396,389
Estimated fair value	491,870	395,633
Due after ten years [Member] | Fixed maturities trading securities allocated to contractual maturity [Member]
Maturity profile
Amortized cost	112,858	3,079
Estimated fair value	111,655	3,095
Asset backed and mortgaged backed securities [Member] | No single maturity date [Member]
Maturity profile
Amortized cost	1,448,393	831,071
Estimated fair value	$1,456,758	$836,915

Investments_Components_of_net_

Investments (Components of net investment income) (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, 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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net investment income
Total gross investment income													$107,548	$103,935	$116,000
Investment expenses													-7,472	-7,863	-8,064
Net investment income	30,167	25,261	21,286	23,362	24,204	20,009	26,210	25,649	28,802	25,489	25,885	27,760	100,076	96,072	107,936
Fixed Maturities And Short Term Investments [Member]
Net investment income
Total gross investment income													97,248	99,216	105,937
Other investments [Member]
Net investment income
Total gross investment income													5,111	0	2,790
Restricted cash and cash and cash equivalents [Member]
Net investment income
Total gross investment income													5,178	4,713	7,259
Securities lending income [Member]
Net investment income
Total gross investment income													$11	$6	$14

Investments_Realized_and_unrea

Investments (Realized and unrealized gains) (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, 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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Fixed maturities, short-term and other investments and cash equivalents
Gross realized gains													$31,316	[1]	$31,402	[1]	$38,905	[1]
Gross realized (losses)													-8,221		-28,144		-20,672
Net realized gains on investments	6,902	4,595	7,858	3,740	4,448	-6,320	3,409	1,721	-4,516	9,063	6,154	7,532	23,095		3,258		18,233
Net unrealized (losses) on investments	-74,119	-84,974	45,427	55,693	20,137	69,967	-141,348	-7,237	-35,857	86,345	-53,574	20,671	-57,973	[1]	-58,481	[1]	17,585	[1]
Total net realized gains and change in net unrealized gains (losses) gains on investments													-34,878		-55,223		35,818
Net Realized and Change in Unrealized Gains Losses on Assets Held In Trust on Behalf of Operating Affiliates													0		88		-88
Net Realized and Change In Unrealized Gains Losses on Catastrophe Bonds													2,702		-2,258		416
Noncontrolling interest													42,258	[1]	1,836	[1]	17,263	[1]
Total net realized gains and change in net unrealized gains (losses) gains on investments excluding non-controlling interest													$10,082		($55,557)		$53,409
[1]	Includes change in net unrealized gains (losses) and realized gains on investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and is included in the Consolidated Statements of Comprehensive Income as net loss (income) attributable to noncontrolling interest.

Investments_Pledged_investment

Investments (Pledged investments) (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Financial Instruments Owned and Pledged as Collateral [Line Items]
Credit facility, commitment	$1,605,000		$1,599,800
Letters of credit issued and outstanding	561,684		751,250
Investments pledged as collateral	1,022,740		1,246,406
$400,000 syndicated unsecured letter of credit facility
Financial Instruments Owned and Pledged as Collateral [Line Items]
Credit facility, commitment	400,000		400,000
Letters of credit issued and outstanding	0		0
Investments pledged as collateral	0		0
$525,000 Four-year syndicated secured credit facility [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Credit facility, commitment	525,000		525,000
Letters of credit issued and outstanding	276,455	[1]	358,567	[1]
Investments pledged as collateral	395,750		507,620
$200,000 secured bi-lateral letter of credit facility
Financial Instruments Owned and Pledged as Collateral [Line Items]
Credit facility, commitment	200,000		200,000
Letters of credit issued and outstanding	15,649	[1]	16,726	[1]
Investments pledged as collateral	35,645		130,256
Talbot FAL Facility
Financial Instruments Owned and Pledged as Collateral [Line Items]
Credit facility, commitment	25,000		25,000
Letters of credit issued and outstanding	25,000	[1]	25,000	[1]
Investments pledged as collateral	31,048		30,801
PaCRe Senior secured letter of credit facility
Financial Instruments Owned and Pledged as Collateral [Line Items]
Credit facility, commitment	10,000		10,000
Letters of credit issued and outstanding	294	[1]	294	[1]
Investments pledged as collateral	0		0
AlphaCat Re secured letter of credit facility
Financial Instruments Owned and Pledged as Collateral [Line Items]
Credit facility, commitment	30,000		24,800
Letters of credit issued and outstanding	30,000	[1]	24,800	[1]
Investments pledged as collateral	30,078		24,806
IPC bi-lateral facility
Financial Instruments Owned and Pledged as Collateral [Line Items]
Credit facility, commitment	40,000		40,000
Letters of credit issued and outstanding	15,897	[1]	20,177	[1]
Investments pledged as collateral	99,437		98,465
$375,000 Flagstone bi-lateral facility
Financial Instruments Owned and Pledged as Collateral [Line Items]
Credit facility, commitment	375,000		375,000
Letters of credit issued and outstanding	198,389	[1]	305,686	[1]
Investments pledged as collateral	$430,782		$454,458
[1]	Indicates utilization of commitment amount, not necessarily drawn borrowings

Investments_Narrative_Details

Investments (Narrative) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Trading Securities and Other Trading Assets [Line Items]
Securities lending - Percent of market value required in collateral	102.00%
Cash, cash equivalents and investments pledged as collateral	$3,285,692	$2,991,322
Investments held in trust	$3,233,872	$2,982,152
AlphaCat ILS Funds
Schedule of Trading Securities and Other Trading Assets [Line Items]
Number of funds	1	2

Fair_value_measurements_Detail

Fair value measurements (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	$5,532,731		$5,542,258
Short-term investments	1,051,074		787,714
Other investments	813,011		704,086
Total investments including assets held in trust, catastrophe bonds and noncontrolling interest	7,396,816		7,034,058
Assets held in trust on behalf of operating affiliates	-732,782	[1]	-651,715	[2]
Catastrophe bonds	-75,664		-55,544
Noncontrolling interest	-430,494	[3]	-489,402	[3]
Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	6,157,876		5,837,397
U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	760,086		1,364,679
Non-U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	278,728		459,068
U.S. states, municipalities and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	449,623		43,120
Agency residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	529,231		311,499
Non-agency residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	37,807		15,759
U.S. corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	1,499,706		1,332,484
Non-U.S. corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	563,162		714,325
Bank loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	449,004		717,116
Catastrophe bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	75,664		74,551
Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	647,482		509,657
Commercial mortgage backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	242,238
Fund of hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	1,775		2,303
Preferred stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	6,334
Hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	496,960	[3]	561,083	[3]
Private equity investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	53,371		13,485
Investment funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	244,832		117,399
Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	9,739		9,816
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	5,532,731		5,542,258
Short-term investments	1,051,074		787,714
Other investments	813,011		704,086
Total investments including assets held in trust, catastrophe bonds and noncontrolling interest	7,396,816		7,034,058
Assets held in trust on behalf of operating affiliates	-732,782	[1]	-651,715	[2]
Catastrophe bonds	-75,664		-55,544
Noncontrolling interest	-430,494	[3]	-489,402	[3]
Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	6,157,876		5,837,397
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Short-term investments	942,716	[1]	783,151	[2]
Other investments	0		0
Total investments including assets held in trust, catastrophe bonds and noncontrolling interest	942,716		783,151
Assets held in trust on behalf of operating affiliates	-732,782	[1]	-651,715	[2]
Catastrophe bonds	0		0
Noncontrolling interest	0	[3]	0	[3]
Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	209,934		131,436
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	5,494,983		5,542,258
Short-term investments	108,358	[1]	4,563	[2]
Other investments	156,118		127,215
Total investments including assets held in trust, catastrophe bonds and noncontrolling interest	5,759,459		5,674,036
Assets held in trust on behalf of operating affiliates	0	[1]	0	[2]
Catastrophe bonds	-70,664		-55,544
Noncontrolling interest	0	[3]	0	[3]
Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	5,688,795		5,618,492
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	37,748		0
Short-term investments	0	[1]	0	[2]
Other investments	656,893		576,871
Total investments including assets held in trust, catastrophe bonds and noncontrolling interest	694,641		576,871
Assets held in trust on behalf of operating affiliates	0	[1]	0	[2]
Catastrophe bonds	-5,000		0
Noncontrolling interest	-430,494	[3]	-489,402	[3]
Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	259,147		87,469
Fair Value, Measurements, Recurring [Member] | U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	760,086		1,364,679
Fair Value, Measurements, Recurring [Member] | U.S. government and government agency | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | U.S. government and government agency | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	760,086		1,364,679
Fair Value, Measurements, Recurring [Member] | U.S. government and government agency | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | Non-U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	278,728		459,068
Fair Value, Measurements, Recurring [Member] | Non-U.S. government and government agency | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | Non-U.S. government and government agency | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	278,728		459,068
Fair Value, Measurements, Recurring [Member] | Non-U.S. government and government agency | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | U.S. states, municipalities and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	449,623		43,120
Fair Value, Measurements, Recurring [Member] | U.S. states, municipalities and political subdivisions | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | U.S. states, municipalities and political subdivisions | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	449,623		43,120
Fair Value, Measurements, Recurring [Member] | U.S. states, municipalities and political subdivisions | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | Agency residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	529,231		311,499
Fair Value, Measurements, Recurring [Member] | Agency residential mortgage-backed securities | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | Agency residential mortgage-backed securities | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	529,231		311,499
Fair Value, Measurements, Recurring [Member] | Agency residential mortgage-backed securities | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | Non-agency residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	37,807		15,759
Fair Value, Measurements, Recurring [Member] | Non-agency residential mortgage-backed securities | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | Non-agency residential mortgage-backed securities | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	37,807		15,759
Fair Value, Measurements, Recurring [Member] | Non-agency residential mortgage-backed securities | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | U.S. corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	1,499,706		1,332,484
Fair Value, Measurements, Recurring [Member] | U.S. corporate | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | U.S. corporate | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	1,499,706		1,332,484
Fair Value, Measurements, Recurring [Member] | U.S. corporate | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | Non-U.S. corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	563,162		714,325
Fair Value, Measurements, Recurring [Member] | Non-U.S. corporate | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | Non-U.S. corporate | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	563,162		714,325
Fair Value, Measurements, Recurring [Member] | Non-U.S. corporate | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | Bank loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	449,004		717,116
Fair Value, Measurements, Recurring [Member] | Bank loans | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | Bank loans | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	416,256		717,116
Fair Value, Measurements, Recurring [Member] | Bank loans | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	32,748		0
Fair Value, Measurements, Recurring [Member] | Catastrophe bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	75,664		74,551
Fair Value, Measurements, Recurring [Member] | Catastrophe bonds | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | Catastrophe bonds | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	70,664		74,551
Fair Value, Measurements, Recurring [Member] | Catastrophe bonds | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	5,000		0
Fair Value, Measurements, Recurring [Member] | Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	647,482		509,657
Fair Value, Measurements, Recurring [Member] | Asset-backed securities | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | Asset-backed securities | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	647,482		509,657
Fair Value, Measurements, Recurring [Member] | Asset-backed securities | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0		0
Fair Value, Measurements, Recurring [Member] | Commercial mortgage backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	242,238
Fair Value, Measurements, Recurring [Member] | Commercial mortgage backed securities | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0
Fair Value, Measurements, Recurring [Member] | Commercial mortgage backed securities | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	242,238
Fair Value, Measurements, Recurring [Member] | Commercial mortgage backed securities | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities	0
Fair Value, Measurements, Recurring [Member] | Fund of hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	1,775		2,303
Fair Value, Measurements, Recurring [Member] | Fund of hedge funds | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0		0
Fair Value, Measurements, Recurring [Member] | Fund of hedge funds | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0		0
Fair Value, Measurements, Recurring [Member] | Fund of hedge funds | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	1,775		2,303
Fair Value, Measurements, Recurring [Member] | Preferred stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	6,334
Fair Value, Measurements, Recurring [Member] | Preferred stock | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0
Fair Value, Measurements, Recurring [Member] | Preferred stock | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	6,334
Fair Value, Measurements, Recurring [Member] | Preferred stock | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0
Fair Value, Measurements, Recurring [Member] | Hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	496,960	[3]	561,083	[3]
Fair Value, Measurements, Recurring [Member] | Hedge funds | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0	[3]	0	[3]
Fair Value, Measurements, Recurring [Member] | Hedge funds | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0	[3]	0	[3]
Fair Value, Measurements, Recurring [Member] | Hedge funds | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	496,960	[3]	561,083	[3]
Fair Value, Measurements, Recurring [Member] | Private equity investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	53,371		13,485
Fair Value, Measurements, Recurring [Member] | Private equity investments | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0		0
Fair Value, Measurements, Recurring [Member] | Private equity investments | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0		0
Fair Value, Measurements, Recurring [Member] | Private equity investments | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	53,371		13,485
Fair Value, Measurements, Recurring [Member] | Investment funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	244,832		117,399
Fair Value, Measurements, Recurring [Member] | Investment funds | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0		0
Fair Value, Measurements, Recurring [Member] | Investment funds | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	140,045		117,399
Fair Value, Measurements, Recurring [Member] | Investment funds | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	104,787		0
Fair Value, Measurements, Recurring [Member] | Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	9,739		9,816
Fair Value, Measurements, Recurring [Member] | Mutual funds | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0		0
Fair Value, Measurements, Recurring [Member] | Mutual funds | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	9,739		9,816
Fair Value, Measurements, Recurring [Member] | Mutual funds | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	$0		$0
[1]	Included in the short-term investments balance are assets held in trust to support AlphaCat's fully collateralized reinsurance transactions. Also, included in the short-term investments balance are investments held by one AlphaCat ILS fund which is consolidated by the Company but in which the Company has an equity interest of less than 100%. The remaining interests are held by third party investors and included in the Consolidated Balance Sheets as redeemable noncontrolling interest.
[2]	Included in the short-term investments balance are assets held in trust to support AlphaCat's fully collateralized reinsurance transactions. Also, included in the short-term investments balance are investments held by two AlphaCat ILS funds which are consolidated by the Company but in which the Company has an equity interest of less than 100%. The remaining interests are held by third party investors and included in the Consolidated Balance Sheets as redeemable noncontrolling interest.
[3]	Included in the hedge funds balance are investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and included in the Consolidated Balance Sheets as noncontrolling interest.

Fair_value_measurements_Level_

Fair value measurements (Level 3 rollforward) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Catastrophe bonds	($75,664)		($55,544)
Noncontrolling interest	-430,494	[1]	-489,402	[1]
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Catastrophe bonds	-75,664		-55,544
Noncontrolling interest	-430,494	[1]	-489,402	[1]
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Level 3, beginning of year	576,871		556,234
Additions to level 3 investments due to Western World acquisition	23,620		0
Purchases	175,129		99,037
Sales	-52,351		-82,000
Issuances	0		0
Settlements	-1,500		0
Realized gains	8,216		6,132
Unrealized (losses)	-42,047		-2,532
Transfers from Level 3 during the year	6,703		0
Level 3, end of year	694,641		576,871
Catastrophe bonds	-5,000		0
Noncontrolling interest	-430,494	[1]	-489,402	[1]
Level 3 investments excluding noncontrolling interest	$259,147		$87,469
[1]	Included in the hedge funds balance are investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and included in the Consolidated Balance Sheets as noncontrolling interest.

Fair_value_measurements_Narrat

Fair value measurements (Narrative) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2014
	funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	704,086		813,011
Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	5,837,397		6,157,876
Long-term Debt, Gross	788,614		786,583
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of funds	1
Investment time lag reporting	1 month
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	704,086		813,011
Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	5,837,397		6,157,876
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	576,871		656,893
Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	87,469		259,147
Ratio of Level 3 investments to total investments (percent)	1.50%		4.20%
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	127,215		156,118
Total investments, excluding assets held in trust, catastrophe bonds and noncontrolling interest	5,618,492		5,688,795
Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	9,816		9,739
Mutual funds | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of funds			2
Mutual funds | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	9,816		9,739
Mutual funds | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0		0
Mutual funds | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	9,816		9,739
Hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	561,083	[1]	496,960	[1]
Hedge funds | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	561,083	[1]	496,960	[1]
Hedge funds | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	561,083	[1]	496,960	[1]
Hedge funds | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0	[1]	0	[1]
AlphaCat ILS Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Company's equity interest in PacRe (percent)	10.00%		10.00%
Noncontrolling interest, equity in PacRe (percent)	90.00%		90.00%
Number of funds			5
Investment funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	117,399		244,832
Investment funds | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of funds			1
Investment funds | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	117,399		244,832
Investment funds | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0		104,787
Investment funds | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	117,399		140,045
Private equity investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	13,485		53,371
Private equity investments | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	13,485		53,371
Private equity investments | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	13,485		53,371
Private equity investments | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0		0
Investments Assumed In Flagstone Acquisition [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of funds			1
Hedge fund side pocket [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment time lag reporting			1 month
AlphaCat ILS Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of funds	2		1
Minimum | Hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment time lag reporting			1 month
Minimum | Private equity investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment time lag reporting	3 months
Maximum | Hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment time lag reporting	3 months
Maximum | Private equity investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment time lag reporting	6 months
[1]	Included in the hedge funds balance are investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and included in the Consolidated Balance Sheets as noncontrolling interest.

Investments_in_affiliates_Summ

Investments in affiliates (Summary of investments in affiliates) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of Equity Method Investments [Line Items]
Investments in affiliates	$261,483	$141,243
Investment Affiliates [Member]
Schedule of Equity Method Investments [Line Items]
Investments in affiliates	63,506	34,500
Operating Affiliates [Member]
Schedule of Equity Method Investments [Line Items]
Investments in affiliates	$197,977	$106,743

Investments_in_affiliates_Inve

Investments in affiliates (Investment affiliate) (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, 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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of Equity Method Investments [Line Items]
Income (loss) from investment affiliate	$530	$1,754	$779	$5,348	$516	$1,044	$1,753	$1,477	($406)	($160)	($398)	$0	$8,411	$4,790	($964)
Investment Affiliates [Member] | Aquiline Financial Services Fund II LP [Member]
Schedule of Equity Method Investments [Line Items]
Balance, beginning of period				34,500				15,218					34,500	15,218
Addition due to Western World acquisition													8,127	0
Capital contributions													12,468	14,492
Income (loss) from investment affiliate													8,411	4,790
Balance, end of period	63,506				34,500								63,506	34,500
Investment in Aquiline - other details
Investment at cost	51,001				32,110								51,001	32,110
Voting ownership %	0.00%				0.00%								0.00%	0.00%
Equity ownership %	8.10%				6.70%								8.10%	6.70%
Carrying value	$63,506				$34,500								$63,506	$34,500

Investments_in_affiliates_Oper

Investments in affiliates (Operating affiliates rollforward) (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, 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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of Equity Method Investments [Line Items]
Income from operating affiliates	$4,143	$3,761	$4,892	$4,927	$5,510	$1,463	$3,793	$3,523	($614)	$6,235	$3,592	$3,367	$17,723	$14,289	$12,580
Operating Affiliates [Member]
Schedule of Equity Method Investments [Line Items]
Balance, beginning of period				106,743				157,111					106,743	157,111
Purchase of shares													37,600	22,000
Gain on redemption of shares													-5,077
Return of investment													-72,467	-86,657
Fair value of retained interest on deconsolidation of AlphaCat ILS fund													113,455
Income from operating affiliates													17,723	14,289
Balance, end of period	197,977				106,743								197,977	106,743
Operating Affiliates [Member] | AlphaCat Re 2011 [Member]
Schedule of Equity Method Investments [Line Items]
Balance, beginning of period				9,809				62,792					9,809	62,792
Purchase of shares													0	0
Gain on redemption of shares													0
Return of investment													-5,825	-54,914
Income from operating affiliates													622	1,931
Balance, end of period	4,606				9,809								4,606	9,809
Operating Affiliates [Member] | AlphaCat Re 2012 [Member]
Schedule of Equity Method Investments [Line Items]
Balance, beginning of period				1,313				29,319					1,313	29,319
Purchase of shares													0	0
Gain on redemption of shares													0
Return of investment													-1,516	-31,743
Income from operating affiliates													938	3,737
Balance, end of period	735				1,313								735	1,313
Operating Affiliates [Member] | AlphaCat 2013 [Member]
Schedule of Equity Method Investments [Line Items]
Balance, beginning of period				51,744				45,000					51,744	45,000
Purchase of shares													0	0
Gain on redemption of shares													0
Return of investment													-52,762	0
Income from operating affiliates													2,086	6,744
Balance, end of period	1,068				51,744								1,068	51,744
Operating Affiliates [Member] | AlphaCat 2014 [Member]
Schedule of Equity Method Investments [Line Items]
Balance, beginning of period				21,982				0					21,982	0
Purchase of shares														22,000
Gain on redemption of shares													0
Return of investment													0	0
Income from operating affiliates													6,103	-18
Balance, end of period	28,085				21,982								28,085	21,982
Operating Affiliates [Member] | AlphaCat 2015 [Member]
Schedule of Equity Method Investments [Line Items]
Balance, beginning of period				0									0
Purchase of shares													25,600
Gain on redemption of shares													0
Return of investment													0
Income from operating affiliates													0
Balance, end of period	25,600												25,600
Operating Affiliates [Member] | AlphaCat ILS Funds
Schedule of Equity Method Investments [Line Items]
Balance, beginning of period				21,895				20,000					21,895	20,000
Purchase of shares													12,000	0
Gain on redemption of shares													-5,077
Return of investment													-12,364	0
Fair value of retained interest on deconsolidation of AlphaCat ILS fund													113,455
Income from operating affiliates													7,974	1,895
Balance, end of period	$137,883				$21,895								$137,883	$21,895

Investments_in_affiliates_Oper1

Investments in affiliates (Operating affiliates - other details) (Details) (Operating Affiliates [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012
Schedule of Equity Method Investments [Line Items]
Investment at cost	$187,100		$97,536
Carrying value	197,977		106,743	157,111
AlphaCat Re 2011 [Member]
Schedule of Equity Method Investments [Line Items]
Investment at cost	4,606		9,882
Voting ownership %	43.70%		43.70%
Equity ownership %	22.30%		22.30%
Carrying value	4,606		9,809	62,792
Summarized Financial Information of Investees [Abstract]
Total assets	20,469
Total liabilities	7,931
Total revenue	3
Net income	2,794
AlphaCat Re 2012 [Member]
Schedule of Equity Method Investments [Line Items]
Investment at cost	735		654
Voting ownership %	49.00%		49.00%
Equity ownership %	37.90%		37.90%
Carrying value	735		1,313	29,319
Summarized Financial Information of Investees [Abstract]
Total assets	3,098
Total liabilities	1,136
Total revenue	0
Net income	2,477
AlphaCat 2013 [Member]
Schedule of Equity Method Investments [Line Items]
Investment at cost	1,068		45,000
Voting ownership %	40.90%		40.90%
Equity ownership %	19.70%		19.70%
Carrying value	1,068		51,744	45,000
Summarized Financial Information of Investees [Abstract]
Total assets	5,490
Total liabilities	65
Total revenue	14,221
Net income	10,595
AlphaCat 2014 [Member]
Schedule of Equity Method Investments [Line Items]
Investment at cost	22,000		22,000
Voting ownership %	42.30%		42.30%
Equity ownership %	19.60%		19.60%
Carrying value	28,085		21,982	0
Summarized Financial Information of Investees [Abstract]
Total assets	193,702
Total liabilities	4,102
Total revenue	45,333
Net income	31,070
AlphaCat 2015 [Member]
Schedule of Equity Method Investments [Line Items]
Investment at cost	25,600
Voting ownership %	40.00%
Equity ownership %	20.00%
Carrying value	25,600		0
Summarized Financial Information of Investees [Abstract]
Total assets	142,843
Total liabilities	0
Total revenue	0
Net income	0
AlphaCat ILS Funds
Schedule of Equity Method Investments [Line Items]
Investment at cost	133,091		20,000
Equity ownership %			9.10%
Carrying value	137,883		21,895	20,000
Summarized Financial Information of Investees [Abstract]
Total assets	1,026,222	[1]
Total liabilities	175,376	[1]
Total revenue	65,320	[1]
Net income	54,421	[1]
BetaCat ILS Funds [Member]
Summarized Financial Information of Investees [Abstract]
Total assets	22,010
Total liabilities	61
Total revenue	32
Net income	($51)
[1]	AlphaCat ILS funds information includes all funds, including those where the Company is not the primary beneficiary.

Investments_in_affiliates_Note

Investments in affiliates (Notes payable and (income) attributable to operating affiliates) (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, 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
Schedule of Equity Method Investments [Line Items]
Notes payable to operating affiliates, beginning of year				$439,272									$439,272
Notes payable to operating affiliates, end of year	671,465				439,272								671,465	439,272
(Income) attributable to operating affiliate investors	-26,566	-25,807	-25,316	-31,710	-26,607	[1]	-11,815	[1]	-20,264	[1]	-10,077	[1]	-109,399	-68,763	0
Variable Interest Entity, Not Primary Beneficiary [Member]
Schedule of Equity Method Investments [Line Items]
Notes payable to operating affiliates, beginning of year				439,272							0		439,272	0
Notes payable to operating affiliates recognized on deconsolidation of AlphaCat ILS fund													178,837
Issuance of notes payable to operating affiliates													680,027	441,126
Redemption of notes payable to operating affiliates													-617,068	-3,553
Foreign exchange gain (loss)													-9,603	1,699
Notes payable to operating affiliates, end of year	671,465				439,272								671,465	439,272
Variable Interest Entity, Not Primary Beneficiary [Member] | AlphaCat 2013 [Member]
Schedule of Equity Method Investments [Line Items]
Notes payable to operating affiliates, beginning of year				223,809							0		223,809	0
Notes payable to operating affiliates recognized on deconsolidation of AlphaCat ILS fund													0
Issuance of notes payable to operating affiliates													0	223,082
Redemption of notes payable to operating affiliates													-223,512	0
Foreign exchange gain (loss)													-297	727
Notes payable to operating affiliates, end of year	0				223,809								0	223,809	0
(Income) attributable to operating affiliate investors													-14,577	-47,329	0
Variable Interest Entity, Not Primary Beneficiary [Member] | AlphaCat 2014 [Member]
Schedule of Equity Method Investments [Line Items]
Notes payable to operating affiliates, beginning of year				0									0
Notes payable to operating affiliates recognized on deconsolidation of AlphaCat ILS fund													0
Issuance of notes payable to operating affiliates													157,914
Redemption of notes payable to operating affiliates													0
Foreign exchange gain (loss)													-530
Notes payable to operating affiliates, end of year	157,384				0								157,384	0
(Income) attributable to operating affiliate investors													-46,100	0	0
Variable Interest Entity, Not Primary Beneficiary [Member] | AlphaCat ILS Funds
Schedule of Equity Method Investments [Line Items]
Notes payable to operating affiliates, beginning of year				215,463							0		215,463	0
Notes payable to operating affiliates recognized on deconsolidation of AlphaCat ILS fund													178,837
Issuance of notes payable to operating affiliates													522,113	218,044
Redemption of notes payable to operating affiliates													-393,556	-3,553
Foreign exchange gain (loss)													-8,776	972
Notes payable to operating affiliates, end of year	514,081				215,463								514,081	215,463	0
(Income) attributable to operating affiliate investors													($48,722)	($21,434)	$0
[1]	This amount had been shown within finance expenses for each of the three months ended March 31, June 30 and September 30, 2013.

Investments_in_affiliates_Narr

Investments in affiliates (Narrative) (Details) (USD $)	12 Months Ended	0 Months Ended				12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 29, 2014	Oct. 02, 2014	Dec. 20, 2011	Nov. 07, 2014	Dec. 31, 2013
	funds
Schedule of Equity Method Investments [Line Items]
Number of Consolidated Funds	1
Variable Funding Notes, Typical Minimum Duration	12 months
AlphaCat ILS Funds
Schedule of Equity Method Investments [Line Items]
Related Party Transaction Capital Commitment		$20,000
AlphaCat ILS fund D
Schedule of Equity Method Investments [Line Items]
Third party subscriptions						35,000
Aquiline Financial Services Fund II LP [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of interest assumed	100.00%
Related Party Transaction Capital Commitment			10,000	50,000
Investment time lag reporting	3 months
Aquiline Financial Services Fund III LP [Member]
Schedule of Equity Method Investments [Line Items]
Related Party Transaction Capital Commitment					100,000
Operating Affiliates [Member]
Schedule of Equity Method Investments [Line Items]
Fair value of retained interest on deconsolidation of AlphaCat ILS fund	113,455
Notes Payable Of Operating Affiliates Portion Due to Company	148,264					63,654
Income Attributable To Operating Affiliates Portion Due to Company	21,756					11,437
Operating Affiliates [Member] | AlphaCat ILS Funds
Schedule of Equity Method Investments [Line Items]
Fair value of retained interest on deconsolidation of AlphaCat ILS fund	113,455
Deconsolidation, Gain (Loss), Amount	1,372
Equity ownership %						9.10%
As Investor In Third Party Economic Interests [Member]
Schedule of Equity Method Investments [Line Items]
Notes Payable Of Operating Affiliates Portion Due to Company	523,201					375,618
Income Attributable To Operating Affiliates Portion Due to Company	87,643					$57,326
Variable Interest Entity, Primary Beneficiary [Member] | AlphaCat ILS fund D
Schedule of Equity Method Investments [Line Items]
Number of Consolidated Funds						1
Variable Interest Entity, Primary Beneficiary [Member] | BetaCat ILS Funds [Member]
Schedule of Equity Method Investments [Line Items]
Number of Consolidated Funds	1
Variable Interest Entity, Primary Beneficiary [Member] | Operating Affiliates [Member] | AlphaCat ILS fund A
Schedule of Equity Method Investments [Line Items]
Equity ownership %	7.90%
Variable Interest Entity, Primary Beneficiary [Member] | Operating Affiliates [Member] | AlphaCat ILS fund B
Schedule of Equity Method Investments [Line Items]
Equity ownership %	39.70%
Variable Interest Entity, Primary Beneficiary [Member] | Operating Affiliates [Member] | AlphaCat ILS fund C
Schedule of Equity Method Investments [Line Items]
Equity ownership %	9.10%

Noncontrolling_interest_Detail

Noncontrolling interest (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, 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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
	funds												funds
Noncontrolling Interest [Line Items]
Number of Consolidated Funds	1												1
Total, beginning of period				$584,169				$434,280					$584,169	$434,280
Issuance of shares													68,200	150,690
Income (loss) attributable to third parties	-61,209	-53,069	35,305	43,509	27,526	45,694	-60,976	-2,549	-27,206	56,746	-45,360	0	-35,464	9,695	-15,820
Adjustment to noncontrolling interest as a result of deconsolidation													-78,354
Redemption of shares														-10,496
Total, end of period	538,551				584,169				434,280				538,551	584,169	434,280
Redeemable Noncontrolling Interest
Noncontrolling Interest [Line Items]
Total, beginning of period				86,512				0					86,512	0
Issuance of shares													68,200	92,190
Income (loss) attributable to third parties													3,598	4,818
Adjustment to noncontrolling interest as a result of deconsolidation													-78,354
Redemption of shares														-10,496
Total, end of period	79,956				86,512								79,956	86,512
Noncontrolling Interest
Noncontrolling Interest [Line Items]
Total, beginning of period				497,657				434,280					497,657	434,280
Issuance of shares													0	58,500
Income (loss) attributable to third parties													-39,062	4,877
Adjustment to noncontrolling interest as a result of deconsolidation													0
Redemption of shares														0
Total, end of period	$458,595				$497,657								$458,595	$497,657
PaCRe Funds
Noncontrolling Interest [Line Items]
Company's equity interest in PacRe (percent)	10.00%				10.00%								10.00%	10.00%
Noncontrolling interest, equity in PacRe (percent)	90.00%				90.00%								90.00%	90.00%

Derivative_instruments_Amount_

Derivative instruments (Amount and balance sheet location) (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Foreign currency forward contracts
Summary of amount of derivatives designated as hedging instruments
Derivative, Number of Instruments Held	1
Not designated as hedging instruments | Foreign currency forward contracts
Summary of amount of derivatives designated as hedging instruments
Notional amount	$26,755		$0
Not designated as hedging instruments | Foreign currency forward contracts | Other assets
Summary of amount of derivatives designated as hedging instruments
Fair value, derivative assets	1,685	[1]	0	[1]
Not designated as hedging instruments | Foreign currency forward contracts | Accounts payable and accrued expenses
Summary of amount of derivatives designated as hedging instruments
Fair value, derivative liabilities	0	[1]	0	[1]
Designated as hedging instruments | Foreign currency forward contracts
Summary of amount of derivatives designated as hedging instruments
Notional amount	189,026		163,576
Designated as hedging instruments | Foreign currency forward contracts | Other assets
Summary of amount of derivatives designated as hedging instruments
Fair value, derivative assets	401	[1]	1,167	[1]
Designated as hedging instruments | Foreign currency forward contracts | Accounts payable and accrued expenses
Summary of amount of derivatives designated as hedging instruments
Fair value, derivative liabilities	3,136	[1]	2,313	[1]
Designated as hedging instruments | Interest rate swap contracts
Summary of amount of derivatives designated as hedging instruments
Notional amount	552,263		552,263
Designated as hedging instruments | Interest rate swap contracts | Other assets
Summary of amount of derivatives designated as hedging instruments
Fair value, derivative assets	25	[1]	0	[1]
Designated as hedging instruments | Interest rate swap contracts | Accounts payable and accrued expenses
Summary of amount of derivatives designated as hedging instruments
Fair value, derivative liabilities	$1,169	[1]	$911	[1]
Junior Subordinated Deferrable Debentures [Member] | Interest rate swap contracts
Summary of amount of derivatives designated as hedging instruments
Derivative, Number of Instruments Held	2
Flagstone Junior Subordinated Deferrable Debentures [Member] | Interest rate swap contracts
Summary of amount of derivatives designated as hedging instruments
Derivative, Number of Instruments Held	3
Flagstone Junior Subordinated Deferrable Debentures [Member] | Cross-currency interest rate swap
Summary of amount of derivatives designated as hedging instruments
Derivative, Number of Instruments Held	1
[1]	Asset and liability derivatives are classified within other assets and accounts payable and accrued expenses respectively on the Consolidated Balance Sheets. The total impact on earnings during the year ended December 31, 2014, recognized in income within other insurance related income and other income, relating to the foreign currency forward contract that was not designated as a hedging instrument was $1,685.

Derivative_instruments_Amount_1

Derivative instruments (Amount included in statement of operations) (Details) (Designated as hedging instruments, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair value hedge | Foreign currency forward contracts | Foreign exchange gain (loss)
Derivatives designated as fair value hedges and related hedged item
Amount of gain (loss) recognized in income on derivative	($11,789)	$1,947	$1,017
Amount of gain (loss) on hedged item recognized in income attributable to risk being hedged	11,789	-1,947	-912
Amount of gain (loss) recognized in income on derivative (ineffective portion)	0	0	105
Cash flow hedge | Interest rate swap contracts
Derivative Instruments designated as a cash flow hedge
Amount of ineffective portion excluded from effectiveness testing	228	0	0
Cash flow hedge | Interest rate swap contracts | Other comprehensive income
Derivative Instruments designated as a cash flow hedge
Amount of effective portion recognized in other comprehensive income	13,302	11,107	1,588
Cash flow hedge | Interest rate swap contracts | Finance expenses
Derivative Instruments designated as a cash flow hedge
Amount of effective portion subsequently reclassified to earnings	($13,074)	($11,107)	($1,588)

Premiums_receivable_Details

Premiums receivable (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Premiums Receivable Reconciliation [Line Items]
Balance at beginning of period	$697,233	$802,159
Change during period	10,414	-104,926
Balance at end of period	707,647	697,233
Premiums in course of collection
Premiums Receivable Reconciliation [Line Items]
Balance at beginning of period	73,702	214,891
Change during period	11,347	-141,189
Balance at end of period	85,049	73,702
Premiums accrued but unbilled
Premiums Receivable Reconciliation [Line Items]
Balance at beginning of period	623,531	587,268
Change during period	-933	36,263
Balance at end of period	$622,598	$623,531

Reserve_for_losses_and_loss_ex2

Reserve for losses and loss expenses (Analysis of paid and unpaid losses and reconciliation of beginning and ending unpaid losses and loss expenses) (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, 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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Reserve for losses and loss expenses, beginning of year				$3,030,399				$3,517,573				$2,631,143	$3,030,399		$3,517,573		$2,631,143
Losses and loss expenses recoverable, beginning of year				-370,154				-439,967				-372,485	-370,154		-439,967		-372,485
Net reserve for losses and loss expenses, beginning of year				2,660,245				3,077,606				2,258,658	2,660,245		3,077,606		2,258,658
Net reserves acquired (disposed)													525,091		-36,519		639,641
Increase (decrease) in net losses and loss expenses incurred in respect of losses occurring in:
Current year													1,024,256		999,380		1,174,415
Prior years													-252,207	[1],[2]	-205,448	[1],[2]	-174,969	[1],[2]
Total incurred losses and loss expenses													772,049	[1]	793,932	[1]	999,446	[1]
Less net losses and loss expenses paid in respect of losses occurring in:
Current year													-245,084		-244,682		-182,146
Prior years													-816,823		-916,796		-653,874
Total net paid losses													-1,061,907		-1,161,478		-836,020
Foreign exchange													-38,550		-13,296		15,881
Net reserve for losses and loss expenses, end of year	2,856,928				2,660,245				3,077,606				2,856,928		2,660,245		3,077,606
Losses and loss expenses recoverable, end of year	377,466				370,154				439,967				377,466		370,154		439,967
Reserve for losses and loss expenses, end of year	3,234,394				3,030,399				3,517,573				3,234,394		3,030,399		3,517,573
Incurred losses and loss adjustment expenses comprise:
Gross losses and loss adjustment expenses													833,860	[1]	924,986	[1]	1,192,494	[1]
Reinsurance recoverable													-61,811		-131,054		-193,048
Total incurred losses and loss expenses	226,508	224,125	158,745	162,671	206,152	177,965	265,044	144,771	458,310	155,455	153,692	231,989	772,049	[1]	793,932	[1]	999,446	[1]
Liability for unpaid losses and loss expenses by type
Reserves, reported claims	1,495,323				1,537,881								1,495,323		1,537,881
Reserves, incurred but not reported claims	$1,739,071				$1,492,518								$1,739,071		$1,492,518
[1]	Upon closing the acquisition of Western World, an adjustment of $15,586 was made to increase net reserves to reflect fair value. This adjustment was amortized to income through a reduction in losses and loss expenses of $4,607 during the year ended December 31, 2014. The remaining fair value adjustment will be amortized in 2015.
[2]	AlphaCat has not had any development on prior accident years.

Reserve_for_losses_and_loss_ex3

Reserve for losses and loss expenses (Prior year development) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	($252,207)	[1],[2]	($205,448)	[1],[2]	($174,969)	[1],[2]
Validus Re
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	-87,600	[2]	-59,258	[2]	-72,561	[2]
AlphaCat
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	-12,201	[2]
Talbot
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	-141,166	[2]	-146,190	[2]	-102,408	[2]
Western World
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	-11,240	[2]
Property
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	-141,021		-127,302		-71,996
Property | Validus Re
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	-76,064		-81,610		-45,733
Property | AlphaCat
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	-12,201
Property | Talbot
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	-53,779		-45,692		-26,263
Property | Western World
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	1,023	[1]
Marine
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	-38,227		-19,387		-51,358
Marine | Validus Re
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	-6,830		26,705		-11,298
Marine | AlphaCat
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	0
Marine | Talbot
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	-31,397		-46,092		-40,060
Marine | Western World
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	0	[1]
Specialty
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	-60,696		-58,759		-51,615
Specialty | Validus Re
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	-4,706		-4,353		-15,530
Specialty | AlphaCat
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	0
Specialty | Talbot
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	-55,990		-54,406		-36,085
Specialty | Western World
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	0	[1]
Liability
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	-12,263
Liability | Validus Re
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	0
Liability | AlphaCat
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	0
Liability | Talbot
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	0
Liability | Western World
Prior Year Development By Segment And Line Of Business [Line Items]
Net favorable development on prior years	($12,263)	[1]
[1]	Upon closing the acquisition of Western World, an adjustment of $15,586 was made to increase net reserves to reflect fair value. This adjustment was amortized to income through a reduction in losses and loss expenses of $4,607 during the year ended December 31, 2014. The remaining fair value adjustment will be amortized in 2015.
[2]	AlphaCat has not had any development on prior accident years.

Reserve_for_losses_and_loss_ex4

Reserve for losses and loss expenses (Narrative) (Details) (Western World, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014
Western World
Prior Year Development By Segment And Line Of Business [Line Items]
Fair value adjustment to net reserves	$15,586
Amortized to income during the period	$4,607

Accounts_payable_and_accrued_e2

Accounts payable and accrued expenses (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Accounts Payable and Accrued Liabilities [Abstract]
Accrued interest on debt	$12,224	$10,686
Subscriptions received in advance on AlphaCat ILS funds	15,400	35,000
Accrued income attributable to operating affiliates	109,399	68,763
Trade and compensation payables	181,222	163,738
Total	$318,245	$278,187

Reinsurance_Effect_on_premiums

Reinsurance (Effect on premiums written and earned) (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, 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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012
Written:
Direct													$683,028		$544,722	$550,491
Assumed													1,680,258		1,856,384	1,615,949
Ceded	-33,623	-30,137	-50,565	-194,908	-24,558	-39,415	-121,396	-187,216	-35,659	-45,743	-119,052	-107,052	-309,233		-372,585	-307,506
Net premiums written	303,024	328,837	605,109	817,083	212,715	317,345	580,917	917,544	276,188	344,472	508,037	730,237	2,054,053		2,028,521	1,858,934
Earned:
Direct													656,974		519,045	535,872
Assumed													1,689,244		1,951,910	1,647,957
Ceded													-343,814		-368,910	-310,613
Net premiums earned	558,748	494,696	466,003	482,957	492,238	531,288	547,458	531,061	499,286	475,104	447,627	451,199	2,002,404		2,102,045	1,873,216
Eliminations [Member]
Written:
Direct													0		0	0
Assumed													-75,810		-80,315	-65,758
Ceded													75,810		80,315	65,758
Net premiums written													0		0	0
Earned:
Direct													0		0	0
Assumed													-83,168		-78,833	-73,934
Ceded													83,168		78,833	73,934
Net premiums earned													0		0	0
Operating Segments | Validus Re
Written:
Direct													0		0	1,551
Assumed													1,136,910		1,242,522	1,130,408
Ceded													-182,056		-226,264	-144,578
Net premiums written													954,854		1,016,258	987,381
Earned:
Direct													0		0	364
Assumed													1,127,894		1,360,735	1,174,681
Ceded													-210,610		-226,798	-151,774
Net premiums earned													917,284		1,133,937	1,023,271
Operating Segments | AlphaCat
Written:
Direct													0		0	0
Assumed													135,181		147,009	21,603
Ceded													-4,348		-525	0
Net premiums written													130,833		146,484	21,603
Earned:
Direct													0		0	0
Assumed													135,884		137,939	17,666
Ceded													-3,534		-525	0
Net premiums earned													132,350		137,414	17,666
Operating Segments | Talbot
Written:
Direct													617,793		544,722	548,940
Assumed													483,977		547,168	529,696
Ceded													-192,211		-226,111	-228,686
Net premiums written													909,559		865,779	849,950
Earned:
Direct													576,136		519,045	535,508
Assumed													508,634		532,069	529,544
Ceded													-204,996		-220,420	-232,773
Net premiums earned													879,774		830,694	832,279
Operating Segments | Western World
Written:
Direct													65,235
Assumed													0
Ceded													-6,428	[1]
Net premiums written													58,807	[1]
Earned:
Direct													80,838
Assumed													0
Ceded													-7,842
Net premiums earned													$72,996	[1]
[1]	The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.

Reinsurance_Reinsurance_recove

Reinsurance (Reinsurance recoverables by reinsurer) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Reinsurance recoverables by reinsurer
Reinsurance recoverable	$415,544	$450,234
Percentage of total reinsurance recoverable	100.00%	100.00%
Reinsurance (Textuals) [Abstract]
Incurred but not reported recoverable	231,129	196,840
Reinsurance Recoverables, Allowance	4,755	5,794
A Minus Or Better Rating [Member]
Reinsurance recoverables by reinsurer
Percentage of total reinsurance recoverable	98.00%	96.70%
Top 10 reinsurers [Member]
Reinsurance recoverables by reinsurer
Reinsurance recoverable	312,205	340,938
Percentage of total reinsurance recoverable	75.10%	75.70%
Top 10 reinsurers [Member] | Swiss Re [Member] | AA- [Member]
Reinsurance recoverables by reinsurer
Reinsurance recoverable	70,848	20,022
Percentage of total reinsurance recoverable	17.00%	4.50%
Top 10 reinsurers [Member] | Lloyds Syndicates [Member] | A (plus) [Member]
Reinsurance recoverables by reinsurer
Reinsurance recoverable	62,318	73,398
Percentage of total reinsurance recoverable	15.00%	16.30%
Top 10 reinsurers [Member] | Everest Re [Member] | A (plus) [Member]
Reinsurance recoverables by reinsurer
Reinsurance recoverable	51,425	48,113
Percentage of total reinsurance recoverable	12.40%	10.70%
Top 10 reinsurers [Member] | Hannover Re [Member] | AA- [Member]
Reinsurance recoverables by reinsurer
Reinsurance recoverable	40,927	41,483
Percentage of total reinsurance recoverable	9.80%	9.20%
Top 10 reinsurers [Member] | Fully Collateralized Reinsurers [Member] | NR [Member]
Reinsurance recoverables by reinsurer
Reinsurance recoverable	23,315	36,683
Percentage of total reinsurance recoverable	5.60%	8.10%
Top 10 reinsurers [Member] | Munich Re [Member] | AA- [Member]
Reinsurance recoverables by reinsurer
Reinsurance recoverable	19,384	12,360
Percentage of total reinsurance recoverable	4.70%	2.70%
Top 10 reinsurers [Member] | Transatlantic Re [Member] | A (plus) [Member]
Reinsurance recoverables by reinsurer
Reinsurance recoverable	12,418	14,114
Percentage of total reinsurance recoverable	3.00%	3.10%
Top 10 reinsurers [Member] | XL Re [Member] | A (plus) [Member]
Reinsurance recoverables by reinsurer
Reinsurance recoverable	11,114	13,300
Percentage of total reinsurance recoverable	2.70%	3.00%
Top 10 reinsurers [Member] | Berkshire Hathaway Homestate [Member] | AA (plus) [Member]
Reinsurance recoverables by reinsurer
Reinsurance recoverable	10,372
Percentage of total reinsurance recoverable	2.50%
Top 10 reinsurers [Member] | Merrimack Mutual Fire Insurance [Member] | A (plus) [Member]
Reinsurance recoverables by reinsurer
Reinsurance recoverable	10,084
Percentage of total reinsurance recoverable	2.40%
Top 10 reinsurers [Member] | National Indemnity [Member] | AA (plus) [Member]
Reinsurance recoverables by reinsurer
Reinsurance recoverable		51,037
Percentage of total reinsurance recoverable		11.30%
Top 10 reinsurers [Member] | Third Point Re [Member] | A- Rating [Member]
Reinsurance recoverables by reinsurer
Reinsurance recoverable		30,428
Percentage of total reinsurance recoverable		6.80%
Other Reinsurers Balances Greater Than One Million Dollars [Member]
Reinsurance recoverables by reinsurer
Reinsurance recoverable	94,247	100,784
Percentage of total reinsurance recoverable	22.70%	22.40%
Other Reinsurers Balances Less Than One Million Dollars [Member]
Reinsurance recoverables by reinsurer
Reinsurance recoverable	$9,092	$8,512
Percentage of total reinsurance recoverable	2.20%	1.90%

Share_capital_Summary_of_commo

Share capital (Summary of common shares issued and outstanding) (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Summary of common shares issued and outstanding
Common shares issued, beginning balance	154,488,497	152,698,191	134,503,065
Options exercised	412,656	351,509	439,065
Warrants exercised		591,480	326,715
Direct issuance of common stock	1,380	1,266	15,841,539
Common shares issued, ending balance	155,554,224	154,488,497	152,698,191
Treasury shares, ending balance	-71,684,379	-58,444,185	-44,776,932
Common shares outstanding, ending balance	83,869,845	96,044,312	107,921,259
Restricted Stock [Member]
Summary of common shares issued and outstanding
Vested, net of shares withheld	615,659	796,838	1,572,634
Restricted share units [Member]
Summary of common shares issued and outstanding
Vested, net of shares withheld	10,265	14,381	15,173
Performance Shares [Member]
Summary of common shares issued and outstanding
Vested, net of shares withheld	25,767	31,897
Deferred share units [Member]
Summary of common shares issued and outstanding
Vested, net of shares withheld		2,935

Share_capital_Information_on_w

Share capital (Information on warrants) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014
Warrant [Member]
Warrant valuation assumptions:
Volatility	30.00%
July 24, 2007 Issuance
Warrant valuation assumptions:
Warrants issued	256,409
Average strike price	20
Volatility	30.00%
Risk-free rate	4.50%
Expected dividend yield	0.00%
Expected term (years)	8 years
Calculated fair value per warrant	11.28
February 3, 2006 Issuance
Warrant valuation assumptions:
Warrants issued	8,593
Average strike price	17.5
Volatility	30.00%
Risk-free rate	4.50%
Expected dividend yield	0.00%
Expected term (years)	10 years
Calculated fair value per warrant	8.89
December 15, 2005 Issuance
Warrant valuation assumptions:
Warrants issued	8,446,727
Average strike price	17.5
Volatility	30.00%
Risk-free rate	4.50%
Expected dividend yield	0.00%
Expected term (years)	10 years
Calculated fair value per warrant	8.89

Share_capital_Narrative_Detail

Share capital (Narrative) (Details) (USD $)	0 Months Ended	12 Months Ended			3 Months Ended
In Thousands, except Share data, unless otherwise specified	Feb. 05, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Nov. 30, 2012
Schedule of Common Stock Issued and Outstanding [Line Items]
Common Stock, Shares Authorized		571,428,571	571,428,571		571,428,571
Common shares, par value		$0.18	$0.18		$0.18
Common Stock, Voting Rights		one vote per share
Maximum Percent Of Outstanding Common Shares Controlled Contingent Under Voting Rights		9.09%
Stock repurchase program, authorized amount	$500,000
Share repurchase program cumulative aggregrate purchase value	1,774,436	2,231,301
Share repurchase program, cumulative shares repurchased		70,045,504
Stock Repurchase Program, Remaining Authorized Repurchase Amount		$43,135			$43,135
Treasury Stock, Shares		71,684,379	58,444,185		71,684,379
Class of Warrant or Right, Outstanding		5,174,114	5,296,056		5,174,114
Number of warrants exercised during period		0	1,114,416
Warrants exercised			591,480	326,715
Percent Of Fair Market Value Per Share On Date Of Payment Of Deferred Share Units		100.00%
Share Based Compensation Non Employee Directors Stock Compensation Plan Deferred Share Units Outstanding		0	0		0
Deferred share units [Member]
Schedule of Common Stock Issued and Outstanding [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period			5,039
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Net Of Shares Withheld For Taxes			2,935
Flagstone Reinsurance Holdings Sa
Schedule of Common Stock Issued and Outstanding [Line Items]
Business Acquisition Equity Interests Issued Or Issuable Number Of Shares Issued Net Of Shares Withheld									14,202,664
Business Acquisition, Cost of Acquired Entity, Equity Interests Withheld For Income Taxes									87,725
Validus closing share price at acquisition									$34.87
Business Combination Acquired Warrants									121,942
Warrant strike price									$62.02
Common shares
Schedule of Common Stock Issued and Outstanding [Line Items]
Common Stock, Dividends, Per Share, Cash Paid					$0.30	$0.30	$0.30	$0.30
Common share equivalents
Schedule of Common Stock Issued and Outstanding [Line Items]
Common Stock, Dividends, Per Share, Cash Paid					$0.30	$0.30	$0.30	$0.30
Warrant [Member]
Schedule of Common Stock Issued and Outstanding [Line Items]
Volatility		30.00%
Validus UPS Ltd [Member] | Flagstone Reinsurance Holdings Sa
Schedule of Common Stock Issued and Outstanding [Line Items]
Treasury Stock, Shares									1,638,875

Retirement_and_pension_plans_S

Retirement and pension plans (Summary of assumptions used in calculations) (Details) (Defined benefit plans)	12 Months Ended
	Dec. 31, 2014
Defined benefit plans
Assumptions used to determine net periodic pension expense:
Discount rate	3.00%
Increase in compensation levels rate	5.00%
Assumptions used to determine benefit obligations:
Discount rate	2.75%
Increase in compensation levels rate	5.00%

Retirement_and_pension_plans_C

Retirement and pension plans (Change in projected benefit obligation, plan assets, and funded status of plan) (Details) (Defined benefit plans, USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2014
Defined benefit plans
Change in benefit obligation:
Projected benefit obligation, beginning of period	$20,885
Service cost	295	295
Interest cost	145	145
Actuarial losses	1
Benefit payments	-24
Settlements	-4,809
Projected benefit obligation, end of period	16,493	16,493
Change in plan assets:
Fair value of plan assets, beginning of period	0
Employer contributions	6,495
Benefit payments	-24
Settlements	-6,471
Fair value of plan assets, end of period	0	0
Funded status, end of period	-16,493	-16,493
Amounts recognized in the balance sheet:
Current liabilities	-559	-559
Noncurrent liabilities	-15,934	-15,934
Net amount recognized	-16,493	-16,493
Amounts recognized in accumulated other comprehensive (loss) income consist of:
Net loss	4,505	4,505
Prior service credit	-4	-4
Net amount recognized	4,501	4,501
Summary of projected benefit obligation, accumulated benefit obligation and fair value of plan assets:
Projected benefit obligation	16,493	16,493
Accumulated benefit obligation	11,971	11,971
Fair value of plan assets	$0	$0

Retirement_and_pension_plans_C1

Retirement and pension plans (Components of net periodic pension expense) (Details) (Defined benefit plans, USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2014
Defined benefit plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	$295	$295
Interest cost	145	145
Amortization of prior service cost		-1
Amortization of net loss		79
Net periodic benefit cost		518
Settlement loss		1,322
Net periodic pension expense		$1,840

Retirement_and_pension_plans_O

Retirement and pension plans (Other changes recognized in other comprehensive income) (Details) (Defined benefit plans, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014
Defined benefit plans
Defined Benefit Plan Disclosure [Line Items]
Net loss	$1,961
Amortization of loss	-317
Amortization of prior service cost	2
Settlement loss	-1,322
Total recognized in other comprehensive (loss) income	324
Total recognized in net pension expense and other comprehensive (loss) income (before tax effects)	$2,164

Retirement_and_pension_plans_E

Retirement and pension plans (Estimated future benefit payments, fiscal year maturity) (Details) (Defined benefit plans, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014
Defined benefit plans
Defined Benefit Plan Disclosure [Line Items]
2015	$559
2016	93
2017	6,921
2018	85
2019	2,160
2020-2024	5,228
Total benefit payments required	15,046
Employer benefit payments/settlements for current year	$4,834

Retirement_and_pension_plans_D

Retirement and pension plans (Defined contribution plans) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined contribution plan
Defined contribution retirement plan expense	$10,606	$7,621	$9,233

Stock_plans_Options_activity_D

Stock plans (Options activity) (Details) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Options Activities
Options outstanding, beginning balance	1,572,713		1,823,947		2,263,012
Options regranted (modified)			1,833,414
Options exercised	-412,656		-351,509		-439,065
Options cancelled (modified)			-1,733,139
Options outstanding, ending balance	1,160,057		1,572,713		1,823,947
Options exercisable	1,160,057		1,572,713		1,823,947		2,263,012
Weighted Average Grant Date Fair Value
Weighted average grant date fair value, beginning balance	$6.66		$6.52		$6.69
Weighted average grant date fair value, options regranted (modified)			$6.76
Weighted average grant date fair value, options exercised	$5.36		$5.94		$7.44
Weighted average grant date fair value, options cancelled (modified)			$6.76
Weighted average grant date fair value, ending balance	$7.12		$6.66		$6.52
Weighted average grant date fair value, options exercisable	$7.12		$6.66		$6.52		$6.69
Weighted Average Grant Date Exercise Price
Weighted average grant date exercise price, beginning balance	$18.88		$20.69		$20.12
Weighted average grant date exercise price, options regranted (modified)			$19.02
Weighted average grant date exercise price, options exercised	$22.07		$22.91		$17.73
Weighted average grant date exercise price, options cancelled (modified)			$20.12
Weighted average grant date exercise price, ending balance	$17.74		$18.88		$20.69
Weighted average grant date exercise price, options exercisable	$17.74		$18.88		$20.69		$20.12
Total intrinsic value	$7,459	[1]	$4,963	[1]	$6,574	[1]
Company proceeds received	$9,107		$8,052		$7,785
[1]	The total intrinsic value in the tables above represent the amount by which the market price of the Company's common stock is greater than the option strike price multiplied by the number of options exercised during the year.

Stock_plans_Other_awards_activ

Stock plans (Other awards activity) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restricted Stock [Member]
Activities
Beginning balance	2,684,745	2,170,547	3,003,547
Granted	1,051,348	1,594,672	921,506
Vested	-797,446	-969,562	-1,719,855
Forfeited	-79,936	-110,912	-34,651
Ending balance	2,858,711	2,684,745	2,170,547
Share Based Payment Award Other Than Options Nonvested Weighted Average Grant Date Fair Value [Abstract]
Weighted average grant date fair value, beginning balance	$33.74	$29.24	$25.77
Weighted average grant date fair value, granted	$37.81	$36.07	$31.47
Weighted average grant date fair value, vested	$31.44	$28.12	$24.40
Weighted average grant date fair value, forfeited	$36.09	$28.34	$27.85
Weighted average grant date fair value, ending balance	$35.81	$33.74	$29.24
Restricted share units [Member]
Activities
Beginning balance	66,518	47,238	53,312
Granted	53,025	36,635	16,633
Vested	-18,325	-21,814	-22,818
Issued in lieu of cash dividends	2,266	4,459	1,504
Forfeited			-1,393
Ending balance	103,484	66,518	47,238
Share Based Payment Award Other Than Options Nonvested Weighted Average Grant Date Fair Value [Abstract]
Weighted average grant date fair value, beginning balance	$33.74	$29.61	$27.60
Weighted average grant date fair value, granted	$38.10	$36.11	$31.77
Weighted average grant date fair value, vested	$30.71	$28.17	$26.49
Weighted average grant date fair value, issued in lieu of cash dividends	$35	$30.70	$28.66
Weighted average grant date fair value, forfeited			$28.57
Weighted average grant date fair value, ending balance	$36.54	$33.74	$29.61
Performance Shares [Member]
Activities
Beginning balance	101,820	220,845	279,019
Granted	52,639	38,386	41,128
Vested	-32,746	-39,094
Forfeited		-18,701	-99,302
Conversion adjustment	-15,344	-99,616
Ending balance	106,369	101,820	220,845
Share Based Payment Award Other Than Options Nonvested Weighted Average Grant Date Fair Value [Abstract]
Weighted average grant date fair value, beginning balance	$33.56	$31.81	$30.77
Weighted average grant date fair value, granted	$37.33	$36.11	$31.38
Weighted average grant date fair value, vested	$32.62	$28.70
Weighted average grant date fair value, forfeited		$31.05	$28.70
Weighted average grant date fair value, conversion adjustment	$31.38	$33.05
Weighted average grant date fair value, ending balance	$36.03	$33.56	$31.81

Stock_plans_Components_of_shar

Stock plans (Components of share compensation expenses) (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, 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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Total share compensation expenses
Share compensation expenses	$8,821	$8,764	$8,341	$7,147	$8,147	$10,527	$6,638	$2,318	$7,126	$7,345	$6,800	$5,438	$33,073	$27,630	$26,709
Options [Member]
Total share compensation expenses
Share compensation expenses													0	0	142
Restricted share awards [Member]
Total share compensation expenses
Share compensation expenses													31,335	27,750	25,145
Restricted share units [Member]
Total share compensation expenses
Share compensation expenses													876	585	499
Performance Shares [Member]
Total share compensation expenses
Share compensation expenses													$862	($705)	$923

Stock_plans_Narrative_Details

Stock plans (Narrative) (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, except 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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stock plans (other details)
Number of shares reserved for issuance under the LTIP and STIP	13,126,896												13,126,896
Remaining number of shares reserved for issuance	903,292												903,292
Share compensation expenses	$8,821	$8,764	$8,341	$7,147	$8,147	$10,527	$6,638	$2,318	$7,126	$7,345	$6,800	$5,438	$33,073	$27,630	$26,709
Intrinsic value of options outstanding	27,573												27,573
Intrinsic value of options exercisable	27,573												27,573
Tax benefit from share compensation expenses													1,610	1,423	1,380
Net windfall taxes on exercise of stock options													3,513
Options [Member]
Stock plans (other details)
Life of options													10 years
Share compensation expenses													0	0	142
Restricted share awards [Member]
Stock plans (other details)
Share compensation expenses													31,335	27,750	25,145
Unrecognized share compensation expenses	74,670				69,219				43,952				74,670	69,219	43,952
Weighted average period of recognizing share based compensation expenses													2 years 8 months 12 days	3 years 2 months 12 days	2 years 7 months 6 days
Restricted share units [Member]
Stock plans (other details)
Share compensation expenses													876	585	499
Unrecognized share compensation expenses	2,774				1,678				978				2,774	1,678	978
Weighted average period of recognizing share based compensation expenses													3 years 1 month 6 days	3 years 4 months 24 days	2 years 7 months 6 days
Performance Shares [Member]
Stock plans (other details)
Share compensation expenses													862	-705	923
Unrecognized share compensation expenses	$2,232				$1,642				$3,328				$2,232	$1,642	$3,328
Weighted average period of recognizing share based compensation expenses													2 years 1 month 6 days	2 years 0 months 4 days	1 year 8 months 12 days
Performance Share Awards Performance Period													P3Y
Special dividend declared and paid [Member]
Stock plans (other details)
Common Stock, Dividends, Per Share, Cash Paid														$2

Debt_and_financing_arrangement2

Debt and financing arrangements (Schedule of finance structure) (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of financing structure and finance expenses
Debt instrument, commitment	$849,477		$851,616
Debt instrument, issued and outstanding	789,277		791,416
Debt instrument, drawn	786,583		788,614
Credit facility, commitment	1,605,000		1,599,800
Letters of credit issued and outstanding	561,684		751,250
Debt instrument and line of credit facility amount committed, total	2,454,477		2,451,416
Debt instrument and line of credit facility outstanding, total	1,350,961		1,542,666
$400,000 Four-year unsecured credit facility [Member]
Schedule of financing structure and finance expenses
Credit facility, commitment	400,000		400,000
Letters of credit issued and outstanding	0	[1]	0	[1]
$525,000 Four-year syndicated secured credit facility [Member]
Schedule of financing structure and finance expenses
Credit facility, commitment	525,000		525,000
Letters of credit issued and outstanding	276,455	[1]	358,567	[1]
$200,000 secured bi-lateral letter of credit facility
Schedule of financing structure and finance expenses
Credit facility, commitment	200,000		200,000
Letters of credit issued and outstanding	15,649	[1]	16,726	[1]
Talbot FAL Facility
Schedule of financing structure and finance expenses
Credit facility, commitment	25,000		25,000
Letters of credit issued and outstanding	25,000	[1]	25,000	[1]
PaCRe Senior secured letter of credit facility
Schedule of financing structure and finance expenses
Credit facility, commitment	10,000		10,000
Letters of credit issued and outstanding	294	[1]	294	[1]
AlphaCat Re secured letter of credit facility
Schedule of financing structure and finance expenses
Credit facility, commitment	30,000		24,800
Letters of credit issued and outstanding	30,000	[1]	24,800	[1]
IPC bi-lateral facility
Schedule of financing structure and finance expenses
Credit facility, commitment	40,000		40,000
Letters of credit issued and outstanding	15,897	[1]	20,177	[1]
$375,000 Flagstone bi-lateral facility
Schedule of financing structure and finance expenses
Credit facility, commitment	375,000		375,000
Letters of credit issued and outstanding	198,389	[1]	305,686	[1]
2010 Senior Notes due 2040 [Member]
Schedule of financing structure and finance expenses
Debt instrument, commitment	250,000		250,000
Debt instrument, issued and outstanding	250,000	[1]	250,000	[1]
Debt instrument, drawn	247,306		247,198
Junior Subordinated Deferrable Debentures[Member]
Schedule of financing structure and finance expenses
Debt instrument, commitment	599,477		601,616
Debt instrument, issued and outstanding	539,277	[1]	541,416	[1]
Debt instrument, drawn	539,277		541,416
2006 Junior Subordinated Deferrable Debentures [Member]
Schedule of financing structure and finance expenses
Debt instrument, commitment	150,000		150,000
Debt instrument, issued and outstanding	150,000	[1]	150,000	[1]
Debt instrument, drawn	150,000		150,000
2007 Junior Subordinated Deferrable Debentures [Member]
Schedule of financing structure and finance expenses
Debt instrument, commitment	200,000		200,000
Debt instrument, issued and outstanding	139,800	[1]	139,800	[1]
Debt instrument, drawn	139,800		139,800
Flagstone 2006 Junior Subordinated Deferrable Interest Notes [Member]
Schedule of financing structure and finance expenses
Debt instrument, commitment	135,727		137,866
Debt instrument, issued and outstanding	135,727	[1]	137,866	[1]
Debt instrument, drawn	135,727		137,866
Flagstone 2007 Junior Subordinated Deferrable Interest Notes [Member]
Schedule of financing structure and finance expenses
Debt instrument, commitment	113,750		113,750
Debt instrument, issued and outstanding	113,750	[1]	113,750	[1]
Debt instrument, drawn	$113,750		$113,750
[1]	Indicates utilization of commitment amount, not necessarily drawn borrowings

Debt_and_financing_arrangement3

Debt and financing arrangements (Summary of notes and debentures) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$849,477		$851,616
2006 Junior Subordinated Deferrable Debentures [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	150,000		150,000
Flagstone 2006 Junior Subordinated Deferrable Interest Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	135,727		137,866
2007 Junior Subordinated Deferrable Debentures [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	200,000		200,000
2010 Senior Notes due 2040 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	250,000		250,000
Debt Information At Issuance [Member] | 2006 Junior Subordinated Deferrable Debentures [Member]
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	15-Jun-06
Debt Instrument, Face Amount	150,000
Debt Instrument, Maturity Date	15-Jun-36
Debt Instrument, Interest Rate, Stated Percentage	9.07%	[1]
Debt Instrument, Frequency of Periodic Payment	Quarterly
Debt Information At Issuance [Member] | Flagstone 2006 Junior Subordinated Deferrable Interest Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	23-Aug-06
Debt Instrument, Face Amount	135,727
Debt Instrument, Maturity Date	15-Sep-36
Debt Instrument, Frequency of Periodic Payment	Quarterly
Debt Information At Issuance [Member] | Flagstone 2006 Junior Subordinated Deferrable Interest Notes [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	3.54%	[2]
Debt Information At Issuance [Member] | 2007 Junior Subordinated Deferrable Debentures [Member]
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	21-Jun-07
Debt Instrument, Face Amount	200,000
Debt Instrument, Maturity Date	15-Jun-37
Debt Instrument, Interest Rate, Stated Percentage	8.48%	[1]
Debt Instrument, Frequency of Periodic Payment	Quarterly
Debt Information At Issuance [Member] | Flagstone 2007 Due July 30 2037 [Member]
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	8-Jun-07
Debt Instrument, Face Amount	88,750
Debt Instrument, Maturity Date	30-Jul-37
Debt Instrument, Frequency of Periodic Payment	Quarterly
Debt Information At Issuance [Member] | Flagstone 2007 Due July 30 2037 [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	3.00%	[2]
Debt Information At Issuance [Member] | Flagstone 2007 Debt Due September 15 2037 [Member]
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	20-Sep-07
Debt Instrument, Face Amount	25,000
Debt Instrument, Maturity Date	15-Sep-37
Debt Instrument, Frequency of Periodic Payment	Quarterly
Debt Information At Issuance [Member] | Flagstone 2007 Debt Due September 15 2037 [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	3.10%	[2]
Debt Information At Issuance [Member] | 2010 Senior Notes due 2040 [Member]
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	26-Jan-10
Debt Instrument, Face Amount	250,000
Debt Instrument, Maturity Date	26-Jan-40
Debt Instrument, Interest Rate, Stated Percentage	8.88%	[1]
Debt Instrument, Frequency of Periodic Payment	Semi-annually in arrears
Debt Outstanding [Member] | 2006 Junior Subordinated Deferrable Debentures [Member]
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	15-Jun-06
Debt Instrument, Face Amount	150,000
Debt Instrument, Maturity Date	15-Jun-36
Debt Instrument, Interest Rate, Effective Percentage	5.83%	[3]
Debt Instrument, Frequency of Periodic Payment	Quarterly
Debt Outstanding [Member] | Flagstone 2006 Junior Subordinated Deferrable Interest Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	23-Aug-06
Debt Instrument, Maturity Date	15-Sep-36
Debt Instrument, Interest Rate, Effective Percentage	6.46%	[3]
Debt Instrument, Frequency of Periodic Payment	Quarterly
Debt Outstanding [Member] | 2007 Junior Subordinated Deferrable Debentures [Member]
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	21-Jun-07
Debt Instrument, Face Amount	200,000
Debt Instrument, Maturity Date	15-Jun-37
Debt Instrument, Interest Rate, Effective Percentage	5.18%	[3]
Debt Instrument, Frequency of Periodic Payment	Quarterly
Debt Outstanding [Member] | Flagstone 2007 Due July 30 2037 [Member]
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	8-Jun-07
Debt Instrument, Face Amount	88,750
Debt Instrument, Maturity Date	30-Jul-37
Debt Instrument, Interest Rate, Effective Percentage	5.90%	[3]
Debt Instrument, Frequency of Periodic Payment	Quarterly
Debt Outstanding [Member] | Flagstone 2007 Debt Due September 15 2037 [Member]
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	20-Sep-07
Debt Instrument, Face Amount	25,000
Debt Instrument, Maturity Date	15-Sep-37
Debt Instrument, Interest Rate, Effective Percentage	5.98%	[3]
Debt Instrument, Frequency of Periodic Payment	Quarterly
Debt Outstanding [Member] | 2010 Senior Notes due 2040 [Member]
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	26-Jan-10
Debt Instrument, Face Amount	$250,000
Debt Instrument, Maturity Date	26-Jan-40
Debt Instrument, Interest Rate, Stated Percentage	8.88%	[1]
Debt Instrument, Frequency of Periodic Payment	Semi-annually in arrears
[1]	Fixed interest rate.
[2]	Variable interest rate is the three-month LIBOR, reset quarterly, plus spread as noted in the table.
[3]	Interest rate has been fixed as a result of interest rate swap contracts entered into by the Company.

Debt_and_financing_arrangement4

Debt and financing arrangements (Components of finance expenses) (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, 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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Components of financial expenses
Finance expenses	$16,474	$15,354	$16,126	$15,900	$16,925	$15,317	$17,566	$14,369	$14,510	$9,362	$13,706	$16,279	$63,854		$64,177		$53,857
Credit Facilities [Member]
Components of financial expenses
Finance expenses													5,516		6,544		11,999
Bank charges [Member]
Components of financial expenses
Finance expenses													427		507		269
AlphaCat ILS Fund Fees [Member]
Components of financial expenses
Finance expenses													3,530	[1]	3,866	[1]	2,432	[1]
Talbot FAL Facility
Components of financial expenses
Finance expenses													-346		182		97
2006 Junior Subordinated Deferrable Debentures [Member]
Components of financial expenses
Finance expenses													8,868		8,868		6,964
2007 Junior Subordinated Deferrable Debentures [Member]
Components of financial expenses
Finance expenses													7,341		7,341		8,922
Flagstone 2006 Junior Subordinated Deferrable Interest Notes [Member]
Components of financial expenses
Finance expenses													9,001		8,259		459
Flagstone 2007 Junior Subordinated Deferrable Interest Notes [Member]
Components of financial expenses
Finance expenses													7,129		6,222		327
2010 Senior Notes due 2040 [Member]
Components of financial expenses
Finance expenses													$22,388		$22,388		$22,388
[1]	Includes finance expenses incurred by AlphaCat Managers, Ltd. in relation to fund raising for the AlphaCat ILS funds, AlphaCat 2015, AlphaCat 2014 and AlphaCat 2013.

Debt_and_financing_arrangement5

Debt and financing arrangements (Narrative) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Debt and financing arrangements [Line Items]
Future repayments of debt	$789,277		$791,416
Credit Facilities
Credit facility, commitment	1,605,000		1,599,800
Letters of credit issued and outstanding	561,684		751,250
Debentures payable	539,277		541,416
Credit Facilities
Credit Facilities
Percent of consolidated net income quarterly increase under covenant	50.00%
Percent of any net proceeds from issuance of common shares	50.00%
Ratio consolidated total debt to net worth under covenant	0.35:1.00
Minimum level of consolidated net worth	2,600,000
Four-year unsecured credit facility [Member]
Credit Facilities
Letter of credit facility period	4 years
Line of credit facility initiation date	9-Mar-12
Credit facility, commitment	400,000		400,000
Letters of credit issued and outstanding	0	[1]	0	[1]
Aggregate commitments, maximum	500,000
Four-year syndicated secured credit facility [Member]
Credit Facilities
Letter of credit facility period	4 years
Line of credit facility initiation date	9-Mar-12
Credit facility, commitment	525,000		525,000
Letters of credit issued and outstanding	276,455	[1]	358,567	[1]
Aggregate commitments, maximum	700,000
Talbot FAL Facility
Credit Facilities
Credit facility, commitment	25,000		25,000
Letters of credit issued and outstanding	25,000	[1]	25,000	[1]
Percent of consolidated net income quarterly increase under covenant	50.00%
Percent of any net proceeds from issuance of common shares	50.00%
Ratio consolidated total debt to net worth under covenant	0.35:1.00
Minimum Level of Funds at Lloyds	300,000
Minimum level of consolidated net worth	3,225,727
IPC bi-lateral facility
Credit Facilities
Credit facility, commitment	40,000		40,000
Letters of credit issued and outstanding	15,897	[1]	20,177	[1]
$200,000 secured bi-lateral letter of credit facility
Credit Facilities
Credit facility, commitment	200,000		200,000
Letters of credit issued and outstanding	15,649	[1]	16,726	[1]
PaCRe Senior secured letter of credit facility
Credit Facilities
Credit facility, commitment	10,000		10,000
Letters of credit issued and outstanding	294	[1]	294	[1]
AlphaCat Re secured letter of credit facility
Credit Facilities
Credit facility, commitment	30,000		24,800
Letters of credit issued and outstanding	30,000	[1]	24,800	[1]
$375,000 Flagstone bi-lateral facility
Credit Facilities
Credit facility, commitment	375,000		375,000
Letters of credit issued and outstanding	198,389	[1]	305,686	[1]
2010 Senior Notes due 2040 [Member]
Debt and financing arrangements [Line Items]
Future repayments of debt	250,000	[1]	250,000	[1]
Credit Facilities
Debentures payable	250,000
Junior Subordinated Deferrable Debentures[Member]
Debt and financing arrangements [Line Items]
Future repayments of debt	539,277	[1]	541,416	[1]
Credit Facilities
Debentures payable	$539,277
Debt Instrument Redemption Period Duration	5 years
Minimum | 2010 Senior Notes due 2040 [Member]
Debt and financing arrangements [Line Items]
Debt Instrument Redemption Required Notice Period	30 days
Maximum | 2010 Senior Notes due 2040 [Member]
Debt and financing arrangements [Line Items]
Debt Instrument Redemption Required Notice Period	60 days
[1]	Indicates utilization of commitment amount, not necessarily drawn borrowings

Income_taxes_Components_of_tax

Income taxes (Components of tax expense) (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, 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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosures [Line Items]
Net income before taxes, income from operating affiliates and (income) attributable to operating affiliate investors													$537,702	$597,218	$382,539
Components of income tax expense:
U.S.													21,257	0	-54
Non-U.S.													26,179	1,781	1,382
Total current income tax expense													47,436	1,781	1,328
U.S.													-24,998	880	134
Non-U.S.													-22,283	-2,278	1,039
Total deferred income tax (benefit) expense													-47,281	-1,398	1,173
U.S.													-3,741	880	80
Non-U.S.													3,896	-497	2,421
Total income tax expense	-243	-953	1,391	-40	603	5	93	-318	615	1,343	404	139	155	383	2,501
Bermuda
Income Tax Disclosures [Line Items]
Net income before taxes, income from operating affiliates and (income) attributable to operating affiliate investors													496,840	601,583	369,675
United Kingdom
Income Tax Disclosures [Line Items]
Net income before taxes, income from operating affiliates and (income) attributable to operating affiliate investors													10,824	4,668	10,277
United States
Income Tax Disclosures [Line Items]
Net income before taxes, income from operating affiliates and (income) attributable to operating affiliate investors													-11,752	-464	3,075
Switzerland
Income Tax Disclosures [Line Items]
Net income before taxes, income from operating affiliates and (income) attributable to operating affiliate investors													9,941	-225	-3,381
Canada
Income Tax Disclosures [Line Items]
Net income before taxes, income from operating affiliates and (income) attributable to operating affiliate investors													2,773	57	391
Other tax jurisdictions
Income Tax Disclosures [Line Items]
Net income before taxes, income from operating affiliates and (income) attributable to operating affiliate investors													$29,076	($8,401)	$2,502

Income_taxes_Reconciliation_of

Income taxes (Reconciliation of effective tax rate) (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, 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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Bermuda tax rate													0.00%	0.00%	0.00%
Tax charge by jurisdiction
Expected tax expense at Bermuda statutory rate of 0%													$0	$0	$0
Foreign tax rate differential													7,993	-2,399	4,882
Change in valuation allowance													-7,284	4,967	0
Tax exempt income and expenses not deductible													-6,055	-263	0
Share compensation tax windfall													3,513	0	0
Impact of enacted changes in tax rates													250	-407	-1,611
Prior years tax adjustments													666	-461	-770
Other													1,072	-1,054	0
Total income tax expense	($243)	($953)	$1,391	($40)	$603	$5	$93	($318)	$615	$1,343	$404	$139	$155	$383	$2,501

Income_taxes_Components_of_net

Income taxes (Components of net deferred tax liability) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Deferred tax asset
Tax losses carried forward	$158,789	$185,955
Deferred compensation	5,527	6,119
Tax credits carried forward	4,016	0
Discounting of loss reserves	13,721	0
Risk premium reserve	3,842	0
Unearned premiums reserve	8,505	0
Pension	5,864	0
Other	6,023	128
Deferred tax asset, gross of valuation allowance	206,287	192,202
Valuation allowance	158,099	177,656
Net deferred tax asset	48,188	14,546
Deferred tax liability
Underwriting profit taxable in future periods	636	28,945
Deferred acquisition costs	3,348	0
Intangibles	8,638	0
Unrealized appreciation on investments	9,101	0
Properties and fixed assets	4,993	3,179
Other	3,192	1,508
Deferred tax liability	29,908	33,632
Net deferred tax asset (liability)	$18,280	($19,086)

Income_taxes_Loss_carryforward

Income taxes (Loss carryforwards) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014
Operating and Capital Loss Carryforwards [Line Items]
Estimated Period For Completion of Income Tax Examinations	36 months
United Kingdom
Operating and Capital Loss Carryforwards [Line Items]
Loss Carryforwards	547
Loss Carryforwards, Tax Effect	118
United States
Operating and Capital Loss Carryforwards [Line Items]
Loss Carryforwards	6,634
Loss Carryforwards, Tax Effect	2,322
Switzerland
Operating and Capital Loss Carryforwards [Line Items]
Loss Carryforwards	267,420
Loss Carryforwards, Tax Effect	56,426
Luxembourg Tax Jurisdiction [Member]
Operating and Capital Loss Carryforwards [Line Items]
Loss Carryforwards	340,245
Loss Carryforwards, Tax Effect	99,352
Singapore Tax Jurisdiction [Member]
Operating and Capital Loss Carryforwards [Line Items]
Loss Carryforwards	5,723
Loss Carryforwards, Tax Effect	572

Accumulated_other_comprehensiv2

Accumulated other comprehensive (loss) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, net of tax, at end of year	$4,046,553	$4,201,751	$4,455,107
Accumulated other comprehensive (loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, net of tax, at beginning of year	-617	-2,953	-6,601
Amounts reclassified to retained earnings	0	4,290	0
Net current period other comprehensive income (loss), net of tax	-7,939	-1,954	3,648
Balance, net of tax, at end of year	-8,556	-617	-2,953
Foreign currency items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, net of tax, at beginning of year	-617	-2,953	-6,601
Amounts reclassified to retained earnings		4,290
Net current period other comprehensive income (loss), net of tax	-7,501	-1,954	3,648
Balance, net of tax, at end of year	-8,118	-617	-2,953
Decrease in minimum pension liability
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, net of tax, at beginning of year	0	0	0
Amounts reclassified to retained earnings		0
Net current period other comprehensive income (loss), net of tax	-210	0	0
Balance, net of tax, at end of year	-210	0	0
Gains and losses on cash flow hedge
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, net of tax, at beginning of year	0	0	0
Amounts reclassified to retained earnings		0
Net current period other comprehensive income (loss), net of tax	-228	0	0
Balance, net of tax, at end of year	($228)	$0	$0

Commitments_and_contingencies_1

Commitments and contingencies (Investment portfolio) (Details) (Concentrations of credit risk [Member])	12 Months Ended
	Dec. 31, 2014
Investment portfolio excluding government and agency securities [Member]
Concentrations Of Credit Risk [Abstract]
Maximum aggregate exposure to single issuer, allowed	3.50%
Aggregate exposure to single issuer, actual	1.00%
Bank Loan Portfolio [Member]
Concentrations Of Credit Risk [Abstract]
Ratio of Level 3 investments to total investments (percent)	6.10%
Investment portfolio excluding bank loans [Member]
Concentrations Of Credit Risk [Abstract]
Allowable percentage holding in downgraded investments	35.00%
Holding in aggregate market value permitted with written pre-authorization	10.00%
Percent of investment portfolio with a credit rating below the minimum required credit rating of Baa3/BBB-	2.80%

Commitments_and_contingencies_2

Commitments and contingencies (Significant brokers) (Details) (Customer Concentration Risk [Member], Gross Premiums Written [Member])	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Aon Benfield Group Ltd [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	20.10%	27.70%	24.20%
Marsh & McLennan [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	28.50%	21.80%	30.10%
Willis Group Holdings Ltd [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	18.00%	19.40%	16.40%

Commitments_and_contingencies_3

Commitments and contingencies (Future minimum lease payments) (Details) (Office Space And Office Equipment [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Office Space And Office Equipment [Member]
Future minimum lease commitments are as follows:
2015	$11,094
2016	8,616
2017	7,514
2018	7,350
2019	7,130
2020 and thereafter	23,784
Total future minimume lease payments	65,488
Total rent expense with respect to operating leases:
Rent expense	$10,540	$10,214	$7,670

Commitments_and_contingencies_4

Commitments and contingencies (Lloyd's syndicate) (Details)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2014
In Thousands, unless otherwise specified	USD ($)	USD ($)	Lloyd's Syndicate 1183 [Member]	Lloyd's Syndicate 1183 [Member]	2015 underwriting year	2014 underwriting year	2013 underwriting year
			USD ($)	GBP (£)	Lloyd's Syndicate 1183 [Member]	Lloyd's Syndicate 1183 [Member]	Lloyd's Syndicate 1183 [Member]
					USD ($)	USD ($)	USD ($)
Funds at Lloyd's and Lloyd's Central Fund
Maximum premium levies assessable, percent			3.00%	3.00%
Estimated underwriting capacity				£ 625,000
Exchange rate			£1 equals $1.5578	£1 equals $1.5578
Maximum premium levies assessable, amount			29,209
Components Of Required Capital [Abstract]
Talbot FAL facility	1,605,000	1,599,800			25,000	25,000	25,000
Group funds					570,100	450,000	403,700
Cash, investments and letters of credit amount					$595,100	$475,000	$428,700

Commitments_and_contingencies_5

Commitments and contingencies (Investment commitments) (Details) (USD $)	12 Months Ended	0 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Nov. 07, 2014	Dec. 29, 2014	Oct. 02, 2014	Dec. 31, 2013
Aquiline Capital Partners II GP Offshore Ltd [Member]
Related Party Transaction [Line Items]
Related Party Transaction Capital Commitment	$50,000
Related Party Transaction Remaining Commitment	7,500				17,890
Fixed maturities commitment [Member]
Related Party Transaction [Line Items]
Other Commitment	7,539
Investment commitment [Member]
Related Party Transaction [Line Items]
Contractual Obligation	153,000				30,000
Other Commitment	83,712				5,045
Aquiline Financial Services Fund III LP [Member]
Related Party Transaction [Line Items]
Related Party Transaction Capital Commitment		100,000
Related Party Transaction Remaining Commitment	100,000
AlphaCat 2015 [Member]
Related Party Transaction [Line Items]
Related Party Transaction Capital Commitment			28,000
Related Party Transaction Remaining Commitment	2,400
AlphaCat ILS Funds
Related Party Transaction [Line Items]
Related Party Transaction Capital Commitment			20,000
Related Party Transaction Remaining Commitment	8,000
Western World Insurance Group, Inc | Aquiline Capital Partners II GP Offshore Ltd [Member]
Related Party Transaction [Line Items]
Related Party Transaction Capital Commitment				10,000
Related Party Transaction Remaining Commitment	$1,499

Commitments_and_contingencies_6

Commitments and contingencies (Other details) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014
Loss Contingencies [Line Items]
Estimated Period For Completion of Income Tax Examinations	36 months
Western World Insurance Group, Inc
Loss Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	3,412

Related_party_transactions_Det

Related party transactions (Details) (USD $)	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Oct. 02, 2014	Dec. 20, 2011	Nov. 07, 2014
	Employee
Aquiline Capital Partners LLC [Member]
Related Party Transaction [Line Items]
Shares owned by related party	523,180
Warrants to purchase shares	2,756,088
Related Parties Number Of Employees	2
Group Ark Insurance Holdings Ltd [Member]
Related Party Transaction [Line Items]
Gross premiums written	2,073,000	$2,899,000	$7,582,000
Premiums receivable	335,000	238,000
Reinsurance premiums ceded	126,000	85,000	90,000
Related Party Transaction Reinsurance Balances Payable	4,000	4,000
Related Party Transaction Loss Reserves Recoverable	1,063,000	3,698,000
Earned premium adjustments	1,982,000	2,911,000	7,625,000
Conning Inc [Member]
Related Party Transaction [Line Items]
Accounts payable and accrued expenses	515,000	283,000
Investment management fees	1,125,000	500,000	809,000
Aquiline Capital Partners II GP Offshore Ltd [Member]
Related Party Transaction [Line Items]
Accounts payable and accrued expenses	0	0
Percentage of interest assumed	100.00%
Related Party Transaction Capital Commitment	50,000,000
Partnership fees incurred	342,000	1,236,000	2,979,000
Capital contributions	12,468,000	14,492,000	14,365,000
Related Party Transaction Remaining Commitment	7,500,000	17,890,000
Aquiline Financial Services Fund II LP [Member]
Related Party Transaction [Line Items]
Percentage of interest assumed	100.00%
Related Party Transaction Capital Commitment				10,000,000	50,000,000
Aquiline Financial Services Fund III LP [Member]
Related Party Transaction [Line Items]
Related Party Transaction Capital Commitment						100,000,000
Partnership fees incurred	0
Capital contributions	0
Related Party Transaction Remaining Commitment	100,000,000

Earnings_per_share_Details

Earnings per share (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, except 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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Basic earnings per share
Net income	$64,699	($13,397)	$188,672	$205,897	$122,858	$229,063	($30,254)	$220,694	($117,922)	$264,044	$122,262	$124,234	$445,871	$542,361	$392,618
Net loss (income) attributable to noncontrolling interest	61,209	53,069	-35,305	-43,509	-27,526	-45,694	60,976	2,549	27,206	-56,746	45,360	0	35,464	-9,695	15,820
Net income (loss) available (attributable) to Validus	125,908	39,672	153,367	162,388	95,332	183,369	30,722	223,243	-90,716	207,298	167,622	124,234	481,335	532,666	408,438
less: Dividends and distributions declared on outstanding warrants													-6,208	-19,214	-6,693
Income available to common shareholders													475,127	513,452	401,745
Weighted average number of common shares outstanding	86,421,127	90,593,329	90,952,523	93,451,999	98,454,907	99,834,563	103,133,188	107,386,438	97,688,338	93,368,775	98,254,186	99,425,140	90,354,745	102,202,274	97,184,110
Basic earnings per share available to common shareholders	$1.44	$0.42	$1.67	$1.72	$0.95	$1.82	$0.28	$1.94	($0.94)	$2.20	$1.69	$1.23	$5.26	$5.02	$4.13
Diluted earnings per share
Net income	64,699	-13,397	188,672	205,897	122,858	229,063	-30,254	220,694	-117,922	264,044	122,262	124,234	445,871	542,361	392,618
Net loss (income) attributable to noncontrolling interest	61,209	53,069	-35,305	-43,509	-27,526	-45,694	60,976	2,549	27,206	-56,746	45,360	0	35,464	-9,695	15,820
Net income (loss) available (attributable) to Validus	125,908	39,672	153,367	162,388	95,332	183,369	30,722	223,243	-90,716	207,298	167,622	124,234	481,335	532,666	408,438
less: Dividends and distributions declared on outstanding warrants													0	-19,214	0
Income (loss) available (attributable) to common shareholders													$481,335	$513,452	$408,438
Weighted average number of common shares outstanding	86,421,127	90,593,329	90,952,523	93,451,999	98,454,907	99,834,563	103,133,188	107,386,438	97,688,338	93,368,775	98,254,186	99,425,140	90,354,745	102,202,274	97,184,110
Weighted average number of common shares outstanding, diluted	90,948,156	91,939,610	95,276,836	97,799,519	102,928,482	103,613,766	104,734,643	110,052,999	97,688,338	98,236,490	103,667,967	105,096,090	94,690,271	103,970,289	102,384,923
Earnings per diluted share available to common shareholders	$1.38	$0.41	$1.61	$1.66	$0.93	$1.77	$0.28	$1.90	($0.94)	$2.11	$1.62	$1.18	$5.08	$4.94	$3.99
Earnings per share (Textuals) [Abstract]
Anti-dilutive securities excluded from the calculation of diluted earnings per share													199,740	366,821	199,446
Warrants [Member]
Diluted earnings per share
Weighted average number diluted shares outstanding adjustment													2,789,032	0	3,137,956
Options [Member]
Diluted earnings per share
Weighted average number diluted shares outstanding adjustment													745,561	1,026,543	769,618
Unvested restricted shares [Member]
Diluted earnings per share
Weighted average number diluted shares outstanding adjustment													800,933	741,472	1,293,239

Segment_information_Details

Segment information (Details) (USD $)	3 Months Ended																					12 Months Ended
In Thousands, 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, 2012		Sep. 30, 2012		Jun. 30, 2012		Mar. 31, 2012		Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
																						segments
Segment Reporting Information [Line Items]
Number of operating segments																						4
Underwriting income
Gross premiums written	$336,647		$358,974	$655,674	$1,011,991	$237,273		$356,760		$702,313		$1,104,760		$311,847		$390,215		$627,089		$837,289		$2,363,286		$2,401,106		$2,166,440
Reinsurance premiums ceded	-33,623		-30,137	-50,565	-194,908	-24,558		-39,415		-121,396		-187,216		-35,659		-45,743		-119,052		-107,052		-309,233		-372,585		-307,506
Net premiums written	303,024		328,837	605,109	817,083	212,715		317,345		580,917		917,544		276,188		344,472		508,037		730,237		2,054,053		2,028,521		1,858,934
Change in unearned premiums	255,724		165,859	-139,106	-334,126	279,523		213,943		-33,459		-386,483		223,098		130,632		-60,410		-279,038		-51,649		73,524		14,282
Net premiums earned	558,748		494,696	466,003	482,957	492,238		531,288		547,458		531,061		499,286		475,104		447,627		451,199		2,002,404		2,102,045		1,873,216
Underwriting deductions
Losses and loss expenses	226,508		224,125	158,745	162,671	206,152		177,965		265,044		144,771		458,310		155,455		153,692		231,989		772,049	[1]	793,932	[1]	999,446	[1]
Policy acquisition costs	89,550		86,404	78,953	85,649	84,647		94,900		87,152		93,611		81,814		98,623		76,129		78,132		340,556		360,310		334,698
General and administrative expenses	98,186		83,319	73,842	74,445	82,930		81,089		70,967		80,279		65,095		70,547		61,635		66,375		329,792		315,265		263,652
Share compensation expenses	8,821		8,764	8,341	7,147	8,147		10,527		6,638		2,318		7,126		7,345		6,800		5,438		33,073		27,630		26,709
Total underwriting deductions	423,065		402,612	319,881	329,912	381,876		364,481		429,801		320,979		612,345		331,970		298,256		381,934		1,475,470		1,497,137		1,624,505
Underwriting income (loss)	135,683		92,084	146,122	153,045	110,362		166,807		117,657		210,082		-113,059		143,134		149,371		69,265		526,934		604,908		248,711
Net investment income	30,167		25,261	21,286	23,362	24,204		20,009		26,210		25,649		28,802		25,489		25,885		27,760		100,076		96,072		107,936
Other insurance related income	5,524		3,610	4,811	8,037	7,743		943		5,512		4,922		144		7,324		6,606		8,237		21,982		19,120		22,311
Finance expenses	-16,474		-15,354	-16,126	-15,900	-16,925		-15,317		-17,566		-14,369		-14,510		-9,362		-13,706		-16,279		-63,854		-64,177		-53,857
Operating income before taxes, (income) from operating affiliates and (income) loss attributable to operating affiliate investors	154,900		105,601	156,093	168,544	125,384		172,442		131,813		226,284		-98,623		166,585		168,156		88,983		585,138		655,923		325,101
Tax benefit (expense)	243		953	-1,391	40	-603		-5		-93		318		-615		-1,343		-404		-139		-155		-383		-2,501
Income from operating affiliates	4,143		3,761	4,892	4,927	5,510		1,463		3,793		3,523		-614		6,235		3,592		3,367		17,723		14,289		12,580
(Income) attributable to operating affiliate investors	-26,566		-25,807	-25,316	-31,710	-26,607	[2]	-11,815	[2]	-20,264	[2]	-10,077	[2]									-109,399		-68,763		0
Net operating income (loss)	132,720		84,508	134,278	141,801	103,684		162,085		115,249		220,048		-99,852		171,477		171,344		92,211		493,307		601,066		335,180
Gain on bargain purchase, net of expenses														21,485	[3]	-3,784	[3]	0	[3]	0	[3]	0		0		17,701	[3]
Net realized gains on investments	6,902		4,595	7,858	3,740	4,448		-6,320		3,409		1,721		-4,516		9,063		6,154		7,532		23,095		3,258		18,233
Net unrealized (losses) on investments	-74,119		-84,974	45,427	55,693	20,137		69,967		-141,348		-7,237		-35,857		86,345		-53,574		20,671		-57,973	[4]	-58,481	[4]	17,585	[4]
Income (loss) from investment affiliate	530		1,754	779	5,348	516		1,044		1,753		1,477		-406		-160		-398		0		8,411		4,790		-964
Foreign exchange (losses) gains	4,131		-11,441	3,158	-6,478	-2,230		6,036		-8,223		6,922		1,181		1,103		-652		3,166		-10,630		2,505		4,798
Other income (loss)	-770		-7,690	424	5,793	-3,697		-3,749		-1,094		-2,237		43		0		-612		654		-2,243		-10,777		85
Transaction expenses	-4,695		-149	-3,252	0																	-8,096	[5]	0		0
Net income	64,699		-13,397	188,672	205,897	122,858		229,063		-30,254		220,694		-117,922		264,044		122,262		124,234		445,871		542,361		392,618
Net loss (income) attributable to noncontrolling interest	61,209		53,069	-35,305	-43,509	-27,526		-45,694		60,976		2,549		27,206		-56,746		45,360		0		35,464		-9,695		15,820
Net income (loss) available (attributable) to Validus	125,908		39,672	153,367	162,388	95,332		183,369		30,722		223,243		-90,716		207,298		167,622		124,234		481,335		532,666		408,438
Selected ratios:
Net premiums written / Gross premiums written																						86.90%	[6]	84.50%	[6]	85.80%	[6]
Losses and loss expenses	40.50%		45.30%	34.10%	33.70%	41.90%		33.50%		48.40%		27.30%		91.80%		32.70%		34.30%		51.40%		38.60%	[6]	37.80%	[6]	53.40%	[6]
Policy acquisition costs																						17.00%	[6]	17.10%	[6]	17.90%	[6]
General and administrative expenses																						18.10%	[6],[7]	16.30%	[6],[7]	15.50%	[6],[7]
Expense ratio	35.20%		36.10%	34.50%	34.60%	35.70%		35.10%		30.10%		33.20%		30.90%		37.20%		32.30%		33.20%		35.10%	[6]	33.40%	[6]	33.40%	[6]
Combined ratio	75.70%		81.40%	68.60%	68.30%	77.60%		68.60%		78.50%		60.50%		122.70%		69.90%		66.60%		84.60%		73.70%	[6]	71.20%	[6]	86.80%	[6]
Total assets	10,311,621					9,846,432								10,020,264								10,311,621		9,846,432		10,020,264
Operating Segments | Validus Re
Underwriting income
Gross premiums written																						1,136,910		1,242,522		1,131,959
Reinsurance premiums ceded																						-182,056		-226,264		-144,578
Net premiums written																						954,854		1,016,258		987,381
Change in unearned premiums																						-37,570		117,679		35,890
Net premiums earned																						917,284		1,133,937		1,023,271
Underwriting deductions
Losses and loss expenses																						307,290		430,026		575,416
Policy acquisition costs																						141,670		180,779		154,362
General and administrative expenses																						74,739		91,260		63,048
Share compensation expenses																						9,739		7,668		7,763
Total underwriting deductions																						533,438		709,733		800,589
Underwriting income (loss)																						383,846		424,204		222,682
Net investment income																						74,599		81,346		88,727
Other insurance related income																						3,159		19,222		5,000
Finance expenses																						-14,727		-16,111		-8,943
Operating income before taxes, (income) from operating affiliates and (income) loss attributable to operating affiliate investors																						446,877		508,661		307,466
Tax benefit (expense)																						5,512		272		-168
Income from operating affiliates																						0		0		0
(Income) attributable to operating affiliate investors																						0		0
Net operating income (loss)																						452,389		508,933		307,298
Gain on bargain purchase, net of expenses																										0	[3]
Net realized gains on investments																						7,611		-1,382		12,026
Net unrealized (losses) on investments																						8,404		-41,388		35,033
Income (loss) from investment affiliate																						8,411		4,790		-964
Foreign exchange (losses) gains																						-6,404		7,394		2,664
Other income (loss)																						-2,243		-10,777		85
Transaction expenses																						0	[5]
Net income																						468,168		467,570		356,142
Net loss (income) attributable to noncontrolling interest																						0		0		0
Net income (loss) available (attributable) to Validus																						468,168		467,570		356,142
Selected ratios:
Net premiums written / Gross premiums written																						84.00%	[6]	81.80%	[6]	87.20%	[6]
Losses and loss expenses																						33.50%	[6]	37.90%	[6]	56.20%	[6]
Policy acquisition costs																						15.50%	[6]	16.00%	[6]	15.10%	[6]
General and administrative expenses																						9.20%	[6],[7]	8.70%	[6],[7]	6.90%	[6],[7]
Expense ratio																						24.70%	[6]	24.70%	[6]	22.00%	[6]
Combined ratio																						58.20%	[6]	62.60%	[6]	78.20%	[6]
Total assets	4,209,289					5,326,076								6,206,084								4,209,289		5,326,076		6,206,084
Operating Segments | AlphaCat
Underwriting income
Gross premiums written																						135,181		147,009		21,603
Reinsurance premiums ceded																						-4,348		-525		0
Net premiums written																						130,833		146,484		21,603
Change in unearned premiums																						1,517		-9,070		-3,937
Net premiums earned																						132,350		137,414		17,666
Underwriting deductions
Losses and loss expenses																						-9,670		17,569		0
Policy acquisition costs																						12,673		13,853		1,774
General and administrative expenses																						19,590		18,765		7,532
Share compensation expenses																						501		468		279
Total underwriting deductions																						23,094		50,655		9,585
Underwriting income (loss)																						109,256		86,759		8,081
Net investment income																						4,276		3,865		3,748
Other insurance related income																						27,122		26,424		23,229
Finance expenses																						-3,545		-5,734		-3,061
Operating income before taxes, (income) from operating affiliates and (income) loss attributable to operating affiliate investors																						137,109		111,314		31,997
Tax benefit (expense)																						0		0		0
Income from operating affiliates																						17,723		14,289		12,580
(Income) attributable to operating affiliate investors																						-109,399		-68,763
Net operating income (loss)																						45,433		56,840		44,577
Gain on bargain purchase, net of expenses																										0	[3]
Net realized gains on investments																						10,935		4,084		216
Net unrealized (losses) on investments																						-56,943		-3,893		-19,509
Income (loss) from investment affiliate																						0		0		0
Foreign exchange (losses) gains																						70		-816		44
Other income (loss)																						0		0		0
Transaction expenses																						0	[5]
Net income																						-505		56,215		25,328
Net loss (income) attributable to noncontrolling interest																						35,464		-9,695		15,820
Net income (loss) available (attributable) to Validus																						34,959		46,520		41,148
Selected ratios:
Net premiums written / Gross premiums written																						96.80%	[6]	99.60%	[6]	100.00%	[6]
Losses and loss expenses																						-7.30%	[6]	12.80%	[6]	0.00%	[6]
Policy acquisition costs																						9.60%	[6]	10.10%	[6]	10.00%	[6]
General and administrative expenses																						15.20%	[6],[7]	14.00%	[6],[7]	44.20%	[6],[7]
Expense ratio																						24.80%	[6]	24.10%	[6]	54.20%	[6]
Combined ratio																						17.50%	[6]	36.90%	[6]	54.20%	[6]
Total assets	1,656,326					1,558,453								805,513								1,656,326		1,558,453		805,513
Operating Segments | Talbot
Underwriting income
Gross premiums written																						1,101,770		1,091,890		1,078,636
Reinsurance premiums ceded																						-192,211		-226,111		-228,686
Net premiums written																						909,559		865,779		849,950
Change in unearned premiums																						-29,785		-35,085		-17,671
Net premiums earned																						879,774		830,694		832,279
Underwriting deductions
Losses and loss expenses																						423,394		346,337		424,030
Policy acquisition costs																						187,162		170,738		183,926
General and administrative expenses																						150,828		136,458		133,281
Share compensation expenses																						11,346		9,613		7,789
Total underwriting deductions																						772,730		663,146		749,026
Underwriting income (loss)																						107,044		167,548		83,253
Net investment income																						20,575		18,061		21,310
Other insurance related income																						1,095		1,819		2,033
Finance expenses																						213		-259		-162
Operating income before taxes, (income) from operating affiliates and (income) loss attributable to operating affiliate investors																						128,927		187,169		106,434
Tax benefit (expense)																						-3,880		-671		-2,229
Income from operating affiliates																						0		0		0
(Income) attributable to operating affiliate investors																						0		0
Net operating income (loss)																						125,047		186,498		104,205
Gain on bargain purchase, net of expenses																										0	[3]
Net realized gains on investments																						3,852		556		5,991
Net unrealized (losses) on investments																						1,685		-13,200		2,061
Income (loss) from investment affiliate																						0		0		0
Foreign exchange (losses) gains																						-5,961		-3,531		2,527
Other income (loss)																						0		0		0
Transaction expenses																						0	[5]
Net income																						124,623		170,323		114,784
Net loss (income) attributable to noncontrolling interest																						0		0		0
Net income (loss) available (attributable) to Validus																						124,623		170,323		114,784
Selected ratios:
Net premiums written / Gross premiums written																						82.60%	[6]	79.30%	[6]	78.80%	[6]
Losses and loss expenses																						48.10%	[6]	41.70%	[6]	50.90%	[6]
Policy acquisition costs																						21.30%	[6]	20.50%	[6]	22.10%	[6]
General and administrative expenses																						18.40%	[6],[7]	17.60%	[6],[7]	16.90%	[6],[7]
Expense ratio																						39.70%	[6]	38.10%	[6]	39.00%	[6]
Combined ratio																						87.80%	[6]	79.80%	[6]	89.90%	[6]
Total assets	2,890,123					2,891,682								2,968,224								2,890,123		2,891,682		2,968,224
Operating Segments | Western World
Underwriting income
Gross premiums written																						65,235	[8]
Reinsurance premiums ceded																						-6,428	[8]
Net premiums written																						58,807	[8]
Change in unearned premiums																						14,189	[8]
Net premiums earned																						72,996	[8]
Underwriting deductions
Losses and loss expenses																						51,035	[8]
Policy acquisition costs																						3,169	[8]
General and administrative expenses																						11,121	[8]
Share compensation expenses																						135	[8]
Total underwriting deductions																						65,460	[8]
Underwriting income (loss)																						7,536	[8]
Net investment income																						4,523	[8]
Other insurance related income																						264	[8]
Finance expenses																						0	[8]
Operating income before taxes, (income) from operating affiliates and (income) loss attributable to operating affiliate investors																						12,323	[8]
Tax benefit (expense)																						-1,422	[8]
Income from operating affiliates																						0	[8]
(Income) attributable to operating affiliate investors																						0	[8]
Net operating income (loss)																						10,901	[8]
Net realized gains on investments																						697	[8]
Net unrealized (losses) on investments																						-155	[8]
Income (loss) from investment affiliate																						0	[8]
Foreign exchange (losses) gains																						0	[8]
Other income (loss)																						0	[8]
Transaction expenses																						0	[5],[8]
Net income																						11,443	[8]
Net loss (income) attributable to noncontrolling interest																						0	[8]
Net income (loss) available (attributable) to Validus																						11,443	[8]
Selected ratios:
Net premiums written / Gross premiums written																						90.10%	[6],[8]
Losses and loss expenses																						69.90%	[6],[8]
Policy acquisition costs																						4.40%	[6],[8]
General and administrative expenses																						15.40%	[6],[7],[8]
Expense ratio																						19.80%	[6],[8]
Combined ratio																						89.70%	[6],[8]
Total assets	1,492,179	[8]																				1,492,179	[8]
Corporate & Eliminations
Underwriting income
Gross premiums written																						-75,810		-80,315		-65,758
Reinsurance premiums ceded																						75,810		80,315		65,758
Net premiums written																						0		0		0
Change in unearned premiums																						0		0		0
Net premiums earned																						0		0		0
Underwriting deductions
Losses and loss expenses																						0		0		0
Policy acquisition costs																						-4,118		-5,060		-5,364
General and administrative expenses																						73,514		68,782		59,791
Share compensation expenses																						11,352		9,881		10,878
Total underwriting deductions																						80,748		73,603		65,305
Underwriting income (loss)																						-80,748		-73,603		-65,305
Net investment income																						-3,897		-7,200		-5,849
Other insurance related income																						-9,658		-28,345		-7,951
Finance expenses																						-45,795		-42,073		-41,691
Operating income before taxes, (income) from operating affiliates and (income) loss attributable to operating affiliate investors																						-140,098		-151,221		-120,796
Tax benefit (expense)																						-365		16		-104
Income from operating affiliates																						0		0		0
(Income) attributable to operating affiliate investors																						0		0
Net operating income (loss)																						-140,463		-151,205		-120,900
Gain on bargain purchase, net of expenses																										17,701	[3]
Net realized gains on investments																						0		0		0
Net unrealized (losses) on investments																						-10,964		0		0
Income (loss) from investment affiliate																						0		0		0
Foreign exchange (losses) gains																						1,665		-542		-437
Other income (loss)																						0		0		0
Transaction expenses																						-8,096	[5]
Net income																						-157,858		-151,747		-103,636
Net loss (income) attributable to noncontrolling interest																						0		0		0
Net income (loss) available (attributable) to Validus																						-157,858		-151,747		-103,636
Selected ratios:
Total assets	$63,704					$70,221								$40,443								$63,704		$70,221		$40,443
[1]	Upon closing the acquisition of Western World, an adjustment of $15,586 was made to increase net reserves to reflect fair value. This adjustment was amortized to income through a reduction in losses and loss expenses of $4,607 during the year ended December 31, 2014. The remaining fair value adjustment will be amortized in 2015.
[2]	This amount had been shown within finance expenses for each of the three months ended March 31, June 30 and September 30, 2013.
[3]	The gain on bargain purchase, net of expenses, arose from the acquisition of Flagstone Reinsurance Holdings S.A. on November 30, 2012 and is net of transaction related expenses which included legal, financial advisory, audit related services and termination expenses.
[4]	Includes change in net unrealized gains (losses) and realized gains on investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and is included in the Consolidated Statements of Comprehensive Income as net loss (income) attributable to noncontrolling interest.
[5]	The transaction expenses relate to costs incurred in connection with the acquisition of Western World, which was completed on October 2, 2014. Transaction expenses are primarily comprised of legal, financial advisory and audit related services.
[6]	Ratios are based on net premiums earned.
[7]	The general and administrative expenses ratio includes share compensation expenses.
[8]	The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.

Segment_information_Gross_writ

Segment information (Gross written premiums by line of business) (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, 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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenue from External Customer [Line Items]
Gross premiums written	$336,647	$358,974	$655,674	$1,011,991	$237,273	$356,760	$702,313	$1,104,760	$311,847	$390,215	$627,089	$837,289	$2,363,286	$2,401,106	$2,166,440
Property
Revenue from External Customer [Line Items]
Gross premiums written													1,054,530	1,164,687	1,060,297
Marine
Revenue from External Customer [Line Items]
Gross premiums written													576,478	570,008	649,421
Specialty
Revenue from External Customer [Line Items]
Gross premiums written													677,026	666,411	456,722
Liability
Revenue from External Customer [Line Items]
Gross premiums written													$55,252	$0	$0

Segment_information_Segment_ge

Segment information (Segment geographic) (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, 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, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written	$336,647	$358,974	$655,674	$1,011,991	$237,273	$356,760	$702,313	$1,104,760	$311,847	$390,215	$627,089	$837,289	$2,363,286		$2,401,106		$2,166,440
Percent of gross premiums written													100.00%		100.00%		100.00%
United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													635,968		662,416		551,641
Percent of gross premiums written													27.00%		27.70%		25.40%
Worldwide excluding United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													221,696	[1]	219,253		180,991	[1]
Percent of gross premiums written													9.40%	[1]	9.10%	[1]	8.40%	[1]
Australia and New Zealand
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													31,012		35,588		13,068
Percent of gross premiums written													1.30%		1.50%		0.60%
Europe
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													104,551		118,615		139,399
Percent of gross premiums written													4.40%		4.90%		6.40%
Latin America and Caribbean
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													146,376		154,053		175,958
Percent of gross premiums written													6.20%		6.40%		8.10%
Japan
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													47,426		48,700		37,016
Percent of gross premiums written													2.00%		2.00%		1.70%
Canada
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													13,865		14,456		12,243
Percent of gross premiums written													0.60%		0.60%		0.60%
Rest of world
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													114,479	[2]	116,989	[2]	159,884	[2]
Percent of gross premiums written													4.80%	[2]	4.90%	[2]	7.40%	[2]
Sub-total, non United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													679,405		707,654		718,559
Percent of gross premiums written													28.70%		29.40%		33.20%
Worldwide including United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													345,304	[1]	324,221	[1]	170,263	[1]
Percent of gross premiums written													14.60%	[1]	13.50%	[1]	7.90%	[1]
Other location non-specific
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													702,609	[3]	706,815	[3]	725,977	[3]
Percent of gross premiums written													29.70%	[3]	29.40%	[3]	33.50%	[3]
Operating Segments | Validus Re
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													1,136,910		1,242,522		1,131,959
Operating Segments | Validus Re | United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													442,314		524,776		463,384
Operating Segments | Validus Re | Worldwide excluding United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													76,129	[1]	63,643	[1]	24,119	[1]
Operating Segments | Validus Re | Australia and New Zealand
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													20,257		22,275		0
Operating Segments | Validus Re | Europe
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													58,236		65,861		87,805
Operating Segments | Validus Re | Latin America and Caribbean
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													54,053		50,522		80,432
Operating Segments | Validus Re | Japan
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													43,310		42,729		30,386
Operating Segments | Validus Re | Canada
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													3,670		3,688		0
Operating Segments | Validus Re | Rest of world
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													21,467	[2]	24,337	[2]	68,754	[2]
Operating Segments | Validus Re | Sub-total, non United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													277,122		273,055		291,496
Operating Segments | Validus Re | Worldwide including United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													179,564	[1]	177,539	[1]	102,080	[1]
Operating Segments | Validus Re | Other location non-specific
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													237,910	[3]	267,152	[3]	274,999	[3]
Operating Segments | AlphaCat
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													135,181		147,009		21,603
Operating Segments | AlphaCat | United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													30,987		50,848		12,638
Operating Segments | AlphaCat | Worldwide excluding United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													7,331	[1]	14,801	[1]	279	[1]
Operating Segments | AlphaCat | Australia and New Zealand
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													1,019		2,216		217
Operating Segments | AlphaCat | Europe
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													3,005		2,533		1,332
Operating Segments | AlphaCat | Latin America and Caribbean
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													0		0		0
Operating Segments | AlphaCat | Japan
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													608		653		0
Operating Segments | AlphaCat | Canada
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													215		818		0
Operating Segments | AlphaCat | Rest of world
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													0	[2]	0	[2]	0	[2]
Operating Segments | AlphaCat | Sub-total, non United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													12,178		21,021		1,828
Operating Segments | AlphaCat | Worldwide including United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													92,016	[1]	75,140	[1]	7,137	[1]
Operating Segments | AlphaCat | Other location non-specific
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													0	[3]	0	[3]	0	[3]
Operating Segments | Talbot
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													1,101,770		1,091,890		1,078,636
Operating Segments | Talbot | United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													108,458		93,357		77,561
Operating Segments | Talbot | Worldwide excluding United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													139,570	[1]	142,294	[1]	156,593	[1]
Operating Segments | Talbot | Australia and New Zealand
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													9,736		11,097		12,851
Operating Segments | Talbot | Europe
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													45,615		51,667		50,262
Operating Segments | Talbot | Latin America and Caribbean
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													116,281		155,798		149,091
Operating Segments | Talbot | Japan
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													4,116		5,971		6,630
Operating Segments | Talbot | Canada
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													10,194		10,768		12,243
Operating Segments | Talbot | Rest of world
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													93,012	[2]	92,652	[2]	91,130	[2]
Operating Segments | Talbot | Sub-total, non United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													418,524		470,247		478,800
Operating Segments | Talbot | Worldwide including United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													96,187	[1]	80,538	[1]	65,084	[1]
Operating Segments | Talbot | Other location non-specific
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													478,601	[3]	447,748	[3]	457,191	[3]
Operating Segments | Western World
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													65,235	[4]
Operating Segments | Western World | United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													65,235
Operating Segments | Western World | Worldwide excluding United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													0	[1]
Operating Segments | Western World | Australia and New Zealand
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													0
Operating Segments | Western World | Europe
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													0
Operating Segments | Western World | Latin America and Caribbean
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													0
Operating Segments | Western World | Japan
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													0
Operating Segments | Western World | Canada
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													0
Operating Segments | Western World | Rest of world
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													0	[2]
Operating Segments | Western World | Sub-total, non United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													0
Operating Segments | Western World | Worldwide including United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													0	[1]
Operating Segments | Western World | Other location non-specific
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													0	[3]
Corporate & Eliminations
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													-75,810		-80,315		-65,758
Corporate & Eliminations | United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													-11,026		-6,565		-1,942
Corporate & Eliminations | Worldwide excluding United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													-1,334	[1]	-1,485	[1]	0	[1]
Corporate & Eliminations | Australia and New Zealand
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													0		0		0
Corporate & Eliminations | Europe
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													-2,305		-1,446		0
Corporate & Eliminations | Latin America and Caribbean
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													-23,958		-52,267		-53,565
Corporate & Eliminations | Japan
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													-608		-653		0
Corporate & Eliminations | Canada
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													-214		-818		0
Corporate & Eliminations | Rest of world
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													0	[2]	0	[2]	0	[2]
Corporate & Eliminations | Sub-total, non United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													-28,419		-56,669		-53,565
Corporate & Eliminations | Worldwide including United States
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													-22,463	[1]	-8,996	[1]	-4,038	[1]
Corporate & Eliminations | Other location non-specific
Gross premiums written allocated to the territory of coverage exposure
Gross premiums written													($13,902)	[3]	($8,085)	[3]	($6,213)	[3]
[1]	Represents risks in two or more geographic zones
[2]	Represents risks in one geographic zone
[3]	The Other locations non-specific category refers to business for which an analysis of exposure by geographic zone is not applicable, such as marine and aerospace risks, since these exposures can span multiple geographic areas and, in some instances, are not fixed locations
[4]	The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.

Statutory_and_regulatory_requi2

Statutory and regulatory requirements (Statutory capital and surplus and statutory net income) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Bermuda
Statutory Accounting Practices [Line Items]
Required statutory capital and surplus	$586,641	[1]	$1,390,179	[1]
Actual statutory capital and surplus	3,793,329	[1]	3,884,572	[1]
Statutory net income (loss)	509,559	[2]	688,001	[2]	496,227	[2]
United States
Statutory Accounting Practices [Line Items]
Required statutory capital and surplus	95,963	[3]	0	[3]
Actual statutory capital and surplus	452,089	[3]	0	[3]
Statutory net income (loss)	105,210	[4]	0	[4]	0	[4]
Switzerland
Statutory Accounting Practices [Line Items]
Required statutory capital and surplus	205,563	[5]	312,563	[5]
Actual statutory capital and surplus	701,010	[5]	939,609	[5]
Statutory net income (loss)	$60,308	[6]	($17,655)	[6]	($1,559)	[6]
[1]	The Company's Bermuda based insurance subsidiaries are required to maintain minimum statutory capital and surplus equal to the greater of a minimum solvency margin ("MSM") and the Enhanced Capital Requirement ("ECR") where applicable. The ECR is equal to the higher of each insurer's MSM or the Bermuda Solvency Capital Requirement ("BSCR") model or approved internal capital model. The BSCR for the relevant insurers for the year ended December 31, 2014 will not be filed with the BMA until April 2015. As a result, the required statutory capital and surplus as at December 31, 2014 is based on the MSM of all relevant insurers, whereas the required statutory capital and surplus as at December 31, 2013 is based on the MSM and ECR where applicable for all relevant insurers. Required statutory capital and surplus includes Validus Reinsurance, Ltd., Validus Reinsurance (Switzerland) Ltd (Bermuda Branch), PaCRe, Ltd., IPCRe Limited, Validus Re Americas, Ltd., Talbot Insurance (Bermuda), Ltd., AlphaCat Reinsurance, Ltd. and Mont Fort Re Ltd. Actual statutory capital and surplus includes Validus Reinsurance, Ltd., AlphaCat Reinsurance, Ltd. and Talbot Insurance (Bermuda), Ltd. Validus Reinsurance, Ltd. is the parent company of the other five Bermuda based insurance subsidiaries.
[2]	Statutory net income includes Validus Reinsurance, Ltd., PaCRe, Ltd. (at the Company's effective 10% equity interest), IPCRe Limited, Validus Re Americas, Ltd., Talbot Insurance (Bermuda), Ltd., AlphaCat Reinsurance, Ltd. and Mont Fort Re Ltd.
[3]	Required statutory capital and surplus is based on the Risk-Based Capital ("RBC") requirements and includes Western World Insurance Company, Tudor Insurance Company and Stratford Insurance Company. Actual statutory capital and surplus includes Western World Insurance Company. Western World Insurance Company is the parent Company of the other two U.S. based insurance subsidiaries. The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.
[4]	Statutory net income includes Western World Insurance Company, Tudor Insurance Company and Stratford Insurance Company. The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.
[5]	Required statutory capital and surplus is based on the Target Capital ("TC") requirements calculated under the Swiss Solvency Test ("SST"). Required and actual statutory capital and surplus includes Validus Reinsurance (Switzerland) Ltd (formerly Flagstone Réassurance Suisse SA).
[6]	Statutory net income (loss) includes Validus Reinsurance (Switzerland) Ltd (formerly Flagstone Réassurance Suisse SA). The results of Validus Reinsurance (Switzerland) Ltd, a former Flagstone subsidiary, have been included in the Company's consolidated results from the November 30, 2012 date of acquisition.

Statutory_and_regulatory_requi3

Statutory and regulatory requirements (Narrative) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
	affiliates
	subsidiaries
	director
Statutory Accounting Practices [Line Items]
Unrestricted net assets available for dividend payments or return of capital	$1,013,379		$516,854
Actual dividends received from subsidiaries	773,966		1,009,000
Bermuda
Statutory Accounting Practices [Line Items]
Actual statutory capital and surplus	3,793,329	[1]	3,884,572	[1]
Statutory net income (loss)	509,559	[2]	688,001	[2]	496,227	[2]
Number of wholly owned subsidiaries	8
Number of affiliates	2
Percentage Of Total Statutory Capital And Surplus Limit	25.00%
Payment Of Dividends Notification Period Required	7 days
Number Of Directors Required For Affidavit	2
Percentage Of Total Statutory Capital Limit	15.00%
United Kingdom
Statutory Accounting Practices [Line Items]
Cash Dividends Payable to Parent Company by Consolidated Subsidiaries	100,000		190,000
United States
Statutory Accounting Practices [Line Items]
Actual statutory capital and surplus	452,089	[3]	0	[3]
Statutory net income (loss)	105,210	[4]	0	[4]	0	[4]
Number of wholly owned subsidiaries	3
Switzerland
Statutory Accounting Practices [Line Items]
Actual statutory capital and surplus	701,010	[5]	939,609	[5]
Statutory net income (loss)	60,308	[6]	-17,655	[6]	-1,559	[6]
Maximum Permitted Dividends Percentage Annual Profit	20.00%
Maximum Permitted Dividends Percentage Statutory Capital	50.00%
Western World Insurance Group, Inc | United States
Statutory Accounting Practices [Line Items]
Statutory Accounting Practices, Statutory Amount Available for Dividend Payments without Regulatory Approval	$45,209
Maximum Permitted Dividends Percentage Statutory Capital	10.00%
[1]	The Company's Bermuda based insurance subsidiaries are required to maintain minimum statutory capital and surplus equal to the greater of a minimum solvency margin ("MSM") and the Enhanced Capital Requirement ("ECR") where applicable. The ECR is equal to the higher of each insurer's MSM or the Bermuda Solvency Capital Requirement ("BSCR") model or approved internal capital model. The BSCR for the relevant insurers for the year ended December 31, 2014 will not be filed with the BMA until April 2015. As a result, the required statutory capital and surplus as at December 31, 2014 is based on the MSM of all relevant insurers, whereas the required statutory capital and surplus as at December 31, 2013 is based on the MSM and ECR where applicable for all relevant insurers. Required statutory capital and surplus includes Validus Reinsurance, Ltd., Validus Reinsurance (Switzerland) Ltd (Bermuda Branch), PaCRe, Ltd., IPCRe Limited, Validus Re Americas, Ltd., Talbot Insurance (Bermuda), Ltd., AlphaCat Reinsurance, Ltd. and Mont Fort Re Ltd. Actual statutory capital and surplus includes Validus Reinsurance, Ltd., AlphaCat Reinsurance, Ltd. and Talbot Insurance (Bermuda), Ltd. Validus Reinsurance, Ltd. is the parent company of the other five Bermuda based insurance subsidiaries.
[2]	Statutory net income includes Validus Reinsurance, Ltd., PaCRe, Ltd. (at the Company's effective 10% equity interest), IPCRe Limited, Validus Re Americas, Ltd., Talbot Insurance (Bermuda), Ltd., AlphaCat Reinsurance, Ltd. and Mont Fort Re Ltd.
[3]	Required statutory capital and surplus is based on the Risk-Based Capital ("RBC") requirements and includes Western World Insurance Company, Tudor Insurance Company and Stratford Insurance Company. Actual statutory capital and surplus includes Western World Insurance Company. Western World Insurance Company is the parent Company of the other two U.S. based insurance subsidiaries. The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.
[4]	Statutory net income includes Western World Insurance Company, Tudor Insurance Company and Stratford Insurance Company. The results of Western World have been included in the Company's consolidated results from the October 2, 2014 date of acquisition.
[5]	Required statutory capital and surplus is based on the Target Capital ("TC") requirements calculated under the Swiss Solvency Test ("SST"). Required and actual statutory capital and surplus includes Validus Reinsurance (Switzerland) Ltd (formerly Flagstone Réassurance Suisse SA).
[6]	Statutory net income (loss) includes Validus Reinsurance (Switzerland) Ltd (formerly Flagstone Réassurance Suisse SA). The results of Validus Reinsurance (Switzerland) Ltd, a former Flagstone subsidiary, have been included in the Company's consolidated results from the November 30, 2012 date of acquisition.

Subsequent_events_Details

Subsequent events (Details) (USD $)	0 Months Ended	12 Months Ended			0 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Feb. 05, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 03, 2015
Subsequent events (Textuals) [Abstract]
Cash dividends declared per share		$1.20	$3.20	$1
Stock repurchase program, authorized amount	$500,000
Share repurchase program cumulative aggregrate purchase value	1,774,436	2,231,301
Common shares
Subsequent events (Textuals) [Abstract]
Cash dividends declared per share		$0.30	$0.30
Common share equivalents
Subsequent events (Textuals) [Abstract]
Cash dividends declared per share		$0.30
Subsequent event
Subsequent events (Textuals) [Abstract]
Stock repurchase program, authorized amount					750,000
Share repurchase program cumulative aggregrate purchase value					$2,274,401
Subsequent event | Common shares
Subsequent events (Textuals) [Abstract]
Cash dividends declared per share					$0.32
Subsequent event | Common share equivalents
Subsequent events (Textuals) [Abstract]
Cash dividends declared per share					$0.32

Condensed_unaudited_quarterly_2

Condensed unaudited quarterly financial information (Details) (USD $)	3 Months Ended																				12 Months Ended
In Thousands, except 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, 2012		Sep. 30, 2012		Jun. 30, 2012		Mar. 31, 2012		Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Underwriting income
Gross premiums written	$336,647	$358,974	$655,674	$1,011,991	$237,273		$356,760		$702,313		$1,104,760		$311,847		$390,215		$627,089		$837,289		$2,363,286		$2,401,106		$2,166,440
Reinsurance premiums ceded	-33,623	-30,137	-50,565	-194,908	-24,558		-39,415		-121,396		-187,216		-35,659		-45,743		-119,052		-107,052		-309,233		-372,585		-307,506
Net premiums written	303,024	328,837	605,109	817,083	212,715		317,345		580,917		917,544		276,188		344,472		508,037		730,237		2,054,053		2,028,521		1,858,934
Change in unearned premiums	255,724	165,859	-139,106	-334,126	279,523		213,943		-33,459		-386,483		223,098		130,632		-60,410		-279,038		-51,649		73,524		14,282
Net premiums earned	558,748	494,696	466,003	482,957	492,238		531,288		547,458		531,061		499,286		475,104		447,627		451,199		2,002,404		2,102,045		1,873,216
Underwriting deductions
Losses and loss expenses	226,508	224,125	158,745	162,671	206,152		177,965		265,044		144,771		458,310		155,455		153,692		231,989		772,049	[1]	793,932	[1]	999,446	[1]
Policy acquisition costs	89,550	86,404	78,953	85,649	84,647		94,900		87,152		93,611		81,814		98,623		76,129		78,132		340,556		360,310		334,698
General and administrative expenses	98,186	83,319	73,842	74,445	82,930		81,089		70,967		80,279		65,095		70,547		61,635		66,375		329,792		315,265		263,652
Share compensation expenses	8,821	8,764	8,341	7,147	8,147		10,527		6,638		2,318		7,126		7,345		6,800		5,438		33,073		27,630		26,709
Total underwriting deductions	423,065	402,612	319,881	329,912	381,876		364,481		429,801		320,979		612,345		331,970		298,256		381,934		1,475,470		1,497,137		1,624,505
Underwriting income (loss)	135,683	92,084	146,122	153,045	110,362		166,807		117,657		210,082		-113,059		143,134		149,371		69,265		526,934		604,908		248,711
Net investment income	30,167	25,261	21,286	23,362	24,204		20,009		26,210		25,649		28,802		25,489		25,885		27,760		100,076		96,072		107,936
Other insurance related income	5,524	3,610	4,811	8,037	7,743		943		5,512		4,922		144		7,324		6,606		8,237		21,982		19,120		22,311
Finance expenses	-16,474	-15,354	-16,126	-15,900	-16,925		-15,317		-17,566		-14,369		-14,510		-9,362		-13,706		-16,279		-63,854		-64,177		-53,857
Operating income before taxes, (income) from operating affiliates and (income) loss attributable to operating affiliate investors	154,900	105,601	156,093	168,544	125,384		172,442		131,813		226,284		-98,623		166,585		168,156		88,983		585,138		655,923		325,101
Tax benefit (expense)	243	953	-1,391	40	-603		-5		-93		318		-615		-1,343		-404		-139		-155		-383		-2,501
Income from operating affiliates	4,143	3,761	4,892	4,927	5,510		1,463		3,793		3,523		-614		6,235		3,592		3,367		17,723		14,289		12,580
(Income) attributable to operating affiliate investors	-26,566	-25,807	-25,316	-31,710	-26,607	[2]	-11,815	[2]	-20,264	[2]	-10,077	[2]									-109,399		-68,763		0
Net operating income (loss)	132,720	84,508	134,278	141,801	103,684		162,085		115,249		220,048		-99,852		171,477		171,344		92,211		493,307		601,066		335,180
Gain on bargain purchase, net of expenses													21,485	[3]	-3,784	[3]	0	[3]	0	[3]	0		0		17,701	[3]
Net realized gains on investments	6,902	4,595	7,858	3,740	4,448		-6,320		3,409		1,721		-4,516		9,063		6,154		7,532		23,095		3,258		18,233
Net unrealized (losses) on investments	-74,119	-84,974	45,427	55,693	20,137		69,967		-141,348		-7,237		-35,857		86,345		-53,574		20,671		-57,973	[4]	-58,481	[4]	17,585	[4]
Income (loss) from investment affiliate	530	1,754	779	5,348	516		1,044		1,753		1,477		-406		-160		-398		0		8,411		4,790		-964
Foreign exchange (losses) gains	4,131	-11,441	3,158	-6,478	-2,230		6,036		-8,223		6,922		1,181		1,103		-652		3,166		-10,630		2,505		4,798
Other income (loss)	-770	-7,690	424	5,793	-3,697		-3,749		-1,094		-2,237		43		0		-612		654		-2,243		-10,777		85
Transaction expenses	-4,695	-149	-3,252	0																	-8,096	[5]	0		0
Net income (loss)	64,699	-13,397	188,672	205,897	122,858		229,063		-30,254		220,694		-117,922		264,044		122,262		124,234		445,871		542,361		392,618
Net loss (income) attributable to noncontrolling interest	61,209	53,069	-35,305	-43,509	-27,526		-45,694		60,976		2,549		27,206		-56,746		45,360		0		35,464		-9,695		15,820
Net income (loss) available (attributable) to Validus	$125,908	$39,672	$153,367	$162,388	$95,332		$183,369		$30,722		$223,243		($90,716)		$207,298		$167,622		$124,234		$481,335		$532,666		$408,438
Earnings per share
Basic (shares)	86,421,127	90,593,329	90,952,523	93,451,999	98,454,907		99,834,563		103,133,188		107,386,438		97,688,338		93,368,775		98,254,186		99,425,140		90,354,745		102,202,274		97,184,110
Diluted (shares)	90,948,156	91,939,610	95,276,836	97,799,519	102,928,482		103,613,766		104,734,643		110,052,999		97,688,338		98,236,490		103,667,967		105,096,090		94,690,271		103,970,289		102,384,923
Basic earnings per share available to common shareholders	$1.44	$0.42	$1.67	$1.72	$0.95		$1.82		$0.28		$1.94		($0.94)		$2.20		$1.69		$1.23		$5.26		$5.02		$4.13
Earnings per diluted share available to common shareholders	$1.38	$0.41	$1.61	$1.66	$0.93		$1.77		$0.28		$1.90		($0.94)		$2.11		$1.62		$1.18		$5.08		$4.94		$3.99
Selected ratios:
Losses and loss expenses	40.50%	45.30%	34.10%	33.70%	41.90%		33.50%		48.40%		27.30%		91.80%		32.70%		34.30%		51.40%		38.60%	[6]	37.80%	[6]	53.40%	[6]
Expense ratio	35.20%	36.10%	34.50%	34.60%	35.70%		35.10%		30.10%		33.20%		30.90%		37.20%		32.30%		33.20%		35.10%	[6]	33.40%	[6]	33.40%	[6]
Combined ratio	75.70%	81.40%	68.60%	68.30%	77.60%		68.60%		78.50%		60.50%		122.70%		69.90%		66.60%		84.60%		73.70%	[6]	71.20%	[6]	86.80%	[6]
[1]	Upon closing the acquisition of Western World, an adjustment of $15,586 was made to increase net reserves to reflect fair value. This adjustment was amortized to income through a reduction in losses and loss expenses of $4,607 during the year ended December 31, 2014. The remaining fair value adjustment will be amortized in 2015.
[2]	This amount had been shown within finance expenses for each of the three months ended March 31, June 30 and September 30, 2013.
[3]	The gain on bargain purchase, net of expenses, arose from the acquisition of Flagstone Reinsurance Holdings S.A. on November 30, 2012 and is net of transaction related expenses which included legal, financial advisory, audit related services and termination expenses.
[4]	Includes change in net unrealized gains (losses) and realized gains on investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and is included in the Consolidated Statements of Comprehensive Income as net loss (income) attributable to noncontrolling interest.
[5]	The transaction expenses relate to costs incurred in connection with the acquisition of Western World, which was completed on October 2, 2014. Transaction expenses are primarily comprised of legal, financial advisory and audit related services.
[6]	Ratios are based on net premiums earned.

Condensed_consolidating_financ2

Condensed consolidating financial information - Condensed Consolidating Balance Sheet (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Assets
Fixed maturities	$5,532,731		$5,542,258
Short term investments, at fair value	1,051,074		787,714
Other investments, at fair value	813,011		704,086
Cash and cash equivalents	577,240		734,148		1,060,722	707,486
Restricted cash	173,003		200,492
Total investments and cash	8,147,059		7,968,698
Investments in affiliates	261,483		141,243
Investment in subsidiaries on an equity basis	0		0
Premiums receivable	707,647		697,233		802,159
Deferred acquisition costs	161,295		134,269
Prepaid reinsurance premiums	81,983		103,251
Securities lending collateral	470		3,392
Loss reserves recoverable	377,466		370,154		439,967	372,485
Paid losses recoverable	38,078		80,080
Deferred tax asset	23,821		0
Intangible assets	126,924		106,407
Goodwill	195,897		20,393		20,393
Intercompany receivable	0		0
Other assets	189,498		221,312
Total assets	10,311,621		9,846,432		10,020,264
Liabilities
Reserve for losses and loss expenses	3,234,394		3,030,399		3,517,573	2,631,143
Unearned premiums	990,564		824,496
Reinsurance balances payable	127,128		154,874
Securities lending payable	936		3,858
Deferred tax liability	5,541		19,086
Net payable for investments purchased	50,256		19,383
Accounts payable and accrued expenses	318,245		278,187
Intercompany payable	0		0
Notes payable to operating affiliates	671,465		439,272
Senior notes payable	247,306		247,198
Debentures payable	539,277		541,416
Total liabilities	6,185,112		5,558,169
Redeemable noncontrolling interest	79,956		86,512
Total shareholders' equity available to Validus	3,587,958		3,704,094		4,020,827
Noncontrolling interest	458,595		497,657		434,280
Total liabilities, noncontrolling interests and shareholders’ equity	10,311,621		9,846,432
Consolidating Adjustments
Assets
Fixed maturities	-60,200	[1]	-60,200	[1]
Short term investments, at fair value	0	[1]	0	[1]
Other investments, at fair value	-68,112	[1]	-66,030	[1]
Cash and cash equivalents	0	[1]	0	[1]
Restricted cash	0	[1]	0	[1]
Total investments and cash	-128,312	[1]	-126,230	[1]
Investments in affiliates	0	[1]	0	[1]
Investment in subsidiaries on an equity basis	-4,797,508	[1]	-4,282,071	[1]
Premiums receivable	0	[1]	0	[1]
Deferred acquisition costs	0	[1]	0	[1]
Prepaid reinsurance premiums	0	[1]	0	[1]
Securities lending collateral	0	[1]	0	[1]
Loss reserves recoverable	0	[1]	0	[1]
Paid losses recoverable	0	[1]	0	[1]
Deferred tax asset	0	[1]
Intangible assets	0	[1]	0	[1]
Goodwill	0	[1]	0	[1]
Intercompany receivable	-41,098	[1]	-29,148	[1]
Other assets	0	[1]	0	[1]
Total assets	-4,966,918	[1]	-4,437,449	[1]
Liabilities
Reserve for losses and loss expenses	0	[1]	0	[1]
Unearned premiums	0	[1]	0	[1]
Reinsurance balances payable	0	[1]	0	[1]
Securities lending payable	0	[1]	0	[1]
Deferred tax liability	0	[1]	0	[1]
Net payable for investments purchased	0	[1]	0	[1]
Accounts payable and accrued expenses	0	[1]	0	[1]
Intercompany payable	-41,098	[1]	-29,148	[1]
Notes payable to operating affiliates	0	[1]	0	[1]
Senior notes payable	0	[1]	0	[1]
Debentures payable	-60,200	[1]	-60,200	[1]
Total liabilities	-101,298	[1]	-89,348	[1]
Redeemable noncontrolling interest	0	[1]	0	[1]
Total shareholders' equity available to Validus	-4,865,620	[1]	-4,348,101	[1]
Noncontrolling interest	0	[1]	0	[1]
Total liabilities, noncontrolling interests and shareholders’ equity	-4,966,918	[1]	-4,437,449	[1]
Validus Holdings, Ltd. (Parent Guarantor)
Assets
Fixed maturities	0		0
Short term investments, at fair value	0		0
Other investments, at fair value	0		0
Cash and cash equivalents	29,798		20,385
Restricted cash	0		0
Total investments and cash	29,798		20,385
Investments in affiliates	0		0
Investment in subsidiaries on an equity basis	4,140,770		4,273,592
Premiums receivable	0		0
Deferred acquisition costs	0		0
Prepaid reinsurance premiums	0		0
Securities lending collateral	0		0
Loss reserves recoverable	0		0
Paid losses recoverable	0		0
Deferred tax asset	0
Intangible assets	0		0
Goodwill	0		0
Intercompany receivable	41,078		29,048
Other assets	3,239		3,767
Total assets	4,214,885		4,326,792
Liabilities
Reserve for losses and loss expenses	0		0
Unearned premiums	0		0
Reinsurance balances payable	0		0
Securities lending payable	0		0
Deferred tax liability	0		0
Net payable for investments purchased	0		0
Accounts payable and accrued expenses	29,621		25,500
Intercompany payable	0		0
Notes payable to operating affiliates	0		0
Senior notes payable	247,306		247,198
Debentures payable	350,000		350,000
Total liabilities	626,927		622,698
Redeemable noncontrolling interest	0		0
Total shareholders' equity available to Validus	3,587,958		3,704,094
Noncontrolling interest	0		0
Total liabilities, noncontrolling interests and shareholders’ equity	4,214,885		4,326,792
Validus Holdings (UK) plc (Subsidiary Issuer)
Assets
Fixed maturities	0		0
Short term investments, at fair value	0		0
Other investments, at fair value	0		0
Cash and cash equivalents	81		0
Restricted cash	0		0
Total investments and cash	81		0
Investments in affiliates	0		0
Investment in subsidiaries on an equity basis	656,738		8,479
Premiums receivable	0		0
Deferred acquisition costs	0		0
Prepaid reinsurance premiums	0		0
Securities lending collateral	0		0
Loss reserves recoverable	0		0
Paid losses recoverable	0		0
Deferred tax asset	0
Intangible assets	0		0
Goodwill	0		0
Intercompany receivable	0		0
Other assets	0		0
Total assets	656,819		8,479
Liabilities
Reserve for losses and loss expenses	0		0
Unearned premiums	0		0
Reinsurance balances payable	0		0
Securities lending payable	0		0
Deferred tax liability	0		0
Net payable for investments purchased	0		0
Accounts payable and accrued expenses	96		0
Intercompany payable	20		100
Notes payable to operating affiliates	0		0
Senior notes payable	0		0
Debentures payable	0		0
Total liabilities	116		100
Redeemable noncontrolling interest	0		0
Total shareholders' equity available to Validus	656,703		8,379
Noncontrolling interest	0		0
Total liabilities, noncontrolling interests and shareholders’ equity	656,819		8,479
Other Validus Holdings, Ltd. Subsidiaries (Non-guarantor Subsidiaries)
Assets
Fixed maturities	5,592,931	[2]	5,602,458	[2]
Short term investments, at fair value	1,051,074	[2]	787,714	[2]
Other investments, at fair value	881,123	[2]	770,116	[2]
Cash and cash equivalents	547,361	[2]	713,763	[2]
Restricted cash	173,003	[2]	200,492	[2]
Total investments and cash	8,245,492	[2]	8,074,543	[2]
Investments in affiliates	261,483	[2]	141,243	[2]
Investment in subsidiaries on an equity basis	0	[2]	0	[2]
Premiums receivable	707,647	[2]	697,233	[2]
Deferred acquisition costs	161,295	[2]	134,269	[2]
Prepaid reinsurance premiums	81,983	[2]	103,251	[2]
Securities lending collateral	470	[2]	3,392	[2]
Loss reserves recoverable	377,466	[2]	370,154	[2]
Paid losses recoverable	38,078	[2]	80,080	[2]
Deferred tax asset	23,821	[2]
Intangible assets	126,924	[2]	106,407	[2]
Goodwill	195,897	[2]	20,393	[2]
Intercompany receivable	20	[2]	100	[2]
Other assets	186,259	[2]	217,545	[2]
Total assets	10,406,835	[2]	9,948,610	[2]
Liabilities
Reserve for losses and loss expenses	3,234,394	[2]	3,030,399	[2]
Unearned premiums	990,564	[2]	824,496	[2]
Reinsurance balances payable	127,128	[2]	154,874	[2]
Securities lending payable	936	[2]	3,858	[2]
Deferred tax liability	5,541	[2]	19,086	[2]
Net payable for investments purchased	50,256	[2]	19,383	[2]
Accounts payable and accrued expenses	288,528	[2]	252,687	[2]
Intercompany payable	41,078	[2]	29,048	[2]
Notes payable to operating affiliates	671,465	[2]	439,272	[2]
Senior notes payable	0	[2]	0	[2]
Debentures payable	249,477	[2]	251,616	[2]
Total liabilities	5,659,367	[2]	5,024,719	[2]
Redeemable noncontrolling interest	79,956	[2]	86,512	[2]
Total shareholders' equity available to Validus	4,208,917	[2]	4,339,722	[2]
Noncontrolling interest	458,595	[2]	497,657	[2]
Total liabilities, noncontrolling interests and shareholders’ equity	$10,406,835	[2]	$9,948,610	[2]
[1]	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
[2]	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.

Condensed_consolidating_financ3

Condensed consolidating financial information - Condensed Consolidating Statement of Comprehensive Income (Details) (USD $)	3 Months Ended																				12 Months Ended
In Thousands, 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, 2012		Sep. 30, 2012		Jun. 30, 2012		Mar. 31, 2012		Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Condensed Statement of Comprehensive Income [Line Items]
Net premiums earned	$558,748	$494,696	$466,003	$482,957	$492,238		$531,288		$547,458		$531,061		$499,286		$475,104		$447,627		$451,199		$2,002,404		$2,102,045		$1,873,216
Gain on bargain purchase, net of expenses													21,485	[1]	-3,784	[1]	0	[1]	0	[1]	0		0		17,701	[1]
Net investment income	30,167	25,261	21,286	23,362	24,204		20,009		26,210		25,649		28,802		25,489		25,885		27,760		100,076		96,072		107,936
Net realized gains on investments	6,902	4,595	7,858	3,740	4,448		-6,320		3,409		1,721		-4,516		9,063		6,154		7,532		23,095		3,258		18,233
Change in net unrealized (losses) gains on investments	-74,119	-84,974	45,427	55,693	20,137		69,967		-141,348		-7,237		-35,857		86,345		-53,574		20,671		-57,973	[2]	-58,481	[2]	17,585	[2]
Income (loss) from investment affiliate	530	1,754	779	5,348	516		1,044		1,753		1,477		-406		-160		-398		0		8,411		4,790		-964
Other insurance related income and other income																					19,739		8,343		22,396
Foreign exchange (losses) gains	4,131	-11,441	3,158	-6,478	-2,230		6,036		-8,223		6,922		1,181		1,103		-652		3,166		-10,630		2,505		4,798
Total revenues																					2,085,122		2,158,532		2,060,901
Losses and loss expenses	226,508	224,125	158,745	162,671	206,152		177,965		265,044		144,771		458,310		155,455		153,692		231,989		772,049	[3]	793,932	[3]	999,446	[3]
Policy acquisition costs	89,550	86,404	78,953	85,649	84,647		94,900		87,152		93,611		81,814		98,623		76,129		78,132		340,556		360,310		334,698
General and administrative expenses	98,186	83,319	73,842	74,445	82,930		81,089		70,967		80,279		65,095		70,547		61,635		66,375		329,792		315,265		263,652
Share compensation expenses	8,821	8,764	8,341	7,147	8,147		10,527		6,638		2,318		7,126		7,345		6,800		5,438		33,073		27,630		26,709
Finance expenses	16,474	15,354	16,126	15,900	16,925		15,317		17,566		14,369		14,510		9,362		13,706		16,279		63,854		64,177		53,857
Transaction expenses	4,695	149	3,252	0																	8,096	[4]	0		0
Total expenses																					1,547,420		1,561,314		1,678,362
Income (loss) before taxes, income from operating affiliates, (income) attributable to operating affiliate investors and equity in net earnings of subsidiaries																					537,702		597,218		382,539
Tax expense	243	953	-1,391	40	-603		-5		-93		318		-615		-1,343		-404		-139		-155		-383		-2,501
Income from operating affiliates	4,143	3,761	4,892	4,927	5,510		1,463		3,793		3,523		-614		6,235		3,592		3,367		17,723		14,289		12,580
(Income) attributable to operating affiliate investors	-26,566	-25,807	-25,316	-31,710	-26,607	[5]	-11,815	[5]	-20,264	[5]	-10,077	[5]									-109,399		-68,763		0
Equity in net earnings of subsidiaries																					0		0		0
Net income (loss)	64,699	-13,397	188,672	205,897	122,858		229,063		-30,254		220,694		-117,922		264,044		122,262		124,234		445,871		542,361		392,618
Net loss (income) attributable to noncontrolling interest	61,209	53,069	-35,305	-43,509	-27,526		-45,694		60,976		2,549		27,206		-56,746		45,360		0		35,464		-9,695		15,820
Net income (loss) available (attributable) to Validus	125,908	39,672	153,367	162,388	95,332		183,369		30,722		223,243		-90,716		207,298		167,622		124,234		481,335		532,666		408,438
Other comprehensive (loss) income																					-7,939		-1,954		3,648
Comprehensive income (loss) available (attributable) to Validus																					473,396		530,712		412,086
Consolidating Adjustments
Condensed Statement of Comprehensive Income [Line Items]
Net premiums earned																					0	[6]	0	[6]	0	[6]
Gain on bargain purchase, net of expenses																									0	[6]
Net investment income																					-3,910	[6]	-7,214	[6]	-5,442	[6]
Net realized gains on investments																					0	[6]	0	[6]	0	[6]
Change in net unrealized (losses) gains on investments																					-2,082	[6]	-8,882	[6]	0	[6]
Income (loss) from investment affiliate																					0	[6]	0	[6]	0	[6]
Other insurance related income and other income																					-67,167	[6]	-67,118	[6]	-14,626	[6]
Foreign exchange (losses) gains																					0	[6]	0	[6]	0	[6]
Total revenues																					-73,159	[6]	-83,214	[6]	-20,068	[6]
Losses and loss expenses																					0	[6]	0	[6]	0	[6]
Policy acquisition costs																					0	[6]	0	[6]	0	[6]
General and administrative expenses																					-67,167	[6]	-67,118	[6]	-14,626	[6]
Share compensation expenses																					0	[6]	0	[6]	0	[6]
Finance expenses																					-1,944	[6]	-1,969	[6]	-3,532	[6]
Transaction expenses																					0	[6]
Total expenses																					-69,111	[6]	-69,087	[6]	-18,158	[6]
Income (loss) before taxes, income from operating affiliates, (income) attributable to operating affiliate investors and equity in net earnings of subsidiaries																					-4,048	[6]	-14,127	[6]	-1,910	[6]
Tax expense																					0	[6]	0	[6]	0	[6]
Income from operating affiliates																					0	[6]	0	[6]	0	[6]
(Income) attributable to operating affiliate investors																					0	[6]	0	[6]
Equity in net earnings of subsidiaries																					-622,834	[6]	-663,400	[6]	-527,880	[6]
Net income (loss)																					-626,882	[6]	-677,527	[6]	-529,790	[6]
Net loss (income) attributable to noncontrolling interest																					0	[6]	0	[6]	0	[6]
Net income (loss) available (attributable) to Validus																					-626,882	[6]	-677,527	[6]	-529,790	[6]
Other comprehensive (loss) income																					7,711	[6]	1,954	[6]	-3,648	[6]
Comprehensive income (loss) available (attributable) to Validus																					-619,171	[6]	-675,573	[6]	-533,438	[6]
Validus Holdings, Ltd. (Parent Guarantor)
Condensed Statement of Comprehensive Income [Line Items]
Net premiums earned																					0		0		0
Gain on bargain purchase, net of expenses																									0
Net investment income																					14		14		3
Net realized gains on investments																					0		0		0
Change in net unrealized (losses) gains on investments																					0		0		0
Income (loss) from investment affiliate																					0		0		0
Other insurance related income and other income																					0		36		0
Foreign exchange (losses) gains																					648		-382		-469
Total revenues																					662		-332		-466
Losses and loss expenses																					0		0		0
Policy acquisition costs																					0		0		0
General and administrative expenses																					86,108		84,143		66,576
Share compensation expenses																					6,424		6,329		8,503
Finance expenses																					47,689		45,868		45,203
Transaction expenses																					0
Total expenses																					140,221		136,340		120,282
Income (loss) before taxes, income from operating affiliates, (income) attributable to operating affiliate investors and equity in net earnings of subsidiaries																					-139,559		-136,672		-120,748
Tax expense																					0		0		0
Income from operating affiliates																					0		0		0
(Income) attributable to operating affiliate investors																					0		0
Equity in net earnings of subsidiaries																					620,894		669,338		529,186
Net income (loss)																					481,335		532,666		408,438
Net loss (income) attributable to noncontrolling interest																					0		0		0
Net income (loss) available (attributable) to Validus																					481,335		532,666		408,438
Other comprehensive (loss) income																					-7,939		-1,954		3,648
Comprehensive income (loss) available (attributable) to Validus																					473,396		530,712		412,086
Validus Holdings (UK) plc (Subsidiary Issuer)
Condensed Statement of Comprehensive Income [Line Items]
Net premiums earned																					0		0		0
Gain on bargain purchase, net of expenses																									0
Net investment income																					0		0		0
Net realized gains on investments																					0		0		0
Change in net unrealized (losses) gains on investments																					0		0		0
Income (loss) from investment affiliate																					0		0		0
Other insurance related income and other income																					0		0		0
Foreign exchange (losses) gains																					1		0		0
Total revenues																					1		0		0
Losses and loss expenses																					0		0		0
Policy acquisition costs																					0		0		0
General and administrative expenses																					117		0		0
Share compensation expenses																					0		0		0
Finance expenses																					0		0		0
Transaction expenses																					0
Total expenses																					117		0		0
Income (loss) before taxes, income from operating affiliates, (income) attributable to operating affiliate investors and equity in net earnings of subsidiaries																					-116		0		0
Tax expense																					0		0		0
Income from operating affiliates																					0		0		0
(Income) attributable to operating affiliate investors																					0		0
Equity in net earnings of subsidiaries																					1,940		-5,938		-1,306
Net income (loss)																					1,824		-5,938		-1,306
Net loss (income) attributable to noncontrolling interest																					0		0		0
Net income (loss) available (attributable) to Validus																					1,824		-5,938		-1,306
Other comprehensive (loss) income																					0		0		0
Comprehensive income (loss) available (attributable) to Validus																					1,824		-5,938		-1,306
Other Validus Holdings, Ltd. Subsidiaries (Non-guarantor Subsidiaries)
Condensed Statement of Comprehensive Income [Line Items]
Net premiums earned																					2,002,404	[7]	2,102,045	[7]	1,873,216	[7]
Gain on bargain purchase, net of expenses																									17,701	[7]
Net investment income																					103,972	[7]	103,272	[7]	113,375	[7]
Net realized gains on investments																					23,095	[7]	3,258	[7]	18,233	[7]
Change in net unrealized (losses) gains on investments																					-55,891	[7]	-49,599	[7]	17,585	[7]
Income (loss) from investment affiliate																					8,411	[7]	4,790	[7]	-964	[7]
Other insurance related income and other income																					86,906	[7]	75,425	[7]	37,022	[7]
Foreign exchange (losses) gains																					-11,279	[7]	2,887	[7]	5,267	[7]
Total revenues																					2,157,618	[7]	2,242,078	[7]	2,081,435	[7]
Losses and loss expenses																					772,049	[7]	793,932	[7]	999,446	[7]
Policy acquisition costs																					340,556	[7]	360,310	[7]	334,698	[7]
General and administrative expenses																					310,734	[7]	298,240	[7]	211,702	[7]
Share compensation expenses																					26,649	[7]	21,301	[7]	18,206	[7]
Finance expenses																					18,109	[7]	20,278	[7]	12,186	[7]
Transaction expenses																					8,096	[7]
Total expenses																					1,476,193	[7]	1,494,061	[7]	1,576,238	[7]
Income (loss) before taxes, income from operating affiliates, (income) attributable to operating affiliate investors and equity in net earnings of subsidiaries																					681,425	[7]	748,017	[7]	505,197	[7]
Tax expense																					-155	[7]	-383	[7]	-2,501	[7]
Income from operating affiliates																					17,723	[7]	14,289	[7]	12,580	[7]
(Income) attributable to operating affiliate investors																					-109,399	[7]	-68,763	[7]
Equity in net earnings of subsidiaries																					0	[7]	0	[7]	0	[7]
Net income (loss)																					589,594	[7]	693,160	[7]	515,276	[7]
Net loss (income) attributable to noncontrolling interest																					35,464	[7]	-9,695	[7]	15,820	[7]
Net income (loss) available (attributable) to Validus																					625,058	[7]	683,465	[7]	531,096	[7]
Other comprehensive (loss) income																					-7,711	[7]	-1,954	[7]	3,648	[7]
Comprehensive income (loss) available (attributable) to Validus																					$617,347	[7]	$681,511	[7]	$534,744	[7]
[1]	The gain on bargain purchase, net of expenses, arose from the acquisition of Flagstone Reinsurance Holdings S.A. on November 30, 2012 and is net of transaction related expenses which included legal, financial advisory, audit related services and termination expenses.
[2]	Includes change in net unrealized gains (losses) and realized gains on investments held by PaCRe in which the Company has an equity interest of 10%. The remaining 90% interest is held by third party investors and is included in the Consolidated Statements of Comprehensive Income as net loss (income) attributable to noncontrolling interest.
[3]	Upon closing the acquisition of Western World, an adjustment of $15,586 was made to increase net reserves to reflect fair value. This adjustment was amortized to income through a reduction in losses and loss expenses of $4,607 during the year ended December 31, 2014. The remaining fair value adjustment will be amortized in 2015.
[4]	The transaction expenses relate to costs incurred in connection with the acquisition of Western World, which was completed on October 2, 2014. Transaction expenses are primarily comprised of legal, financial advisory and audit related services.
[5]	This amount had been shown within finance expenses for each of the three months ended March 31, June 30 and September 30, 2013.
[6]	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
[7]	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.

Condensed_consolidating_financ4

Condensed consolidating financial information - Condensed Consolidating Statement of Cash Flows (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Condensed Consolidating Statement Of Cash Flows, Captions [Line Items]
Net cash (used in) provided by operating activities	$241,781		$265,274		$543,165
Cash flows provided by (used in) investing activities
Proceeds on sales of investments	4,756,555		4,370,548		3,393,740
Proceeds on maturities of investments	554,619		490,459		548,226
Purchases of fixed maturities	-4,379,314		-5,392,728		-3,726,611
(Purchases) sales of short-term investments, net	-121,264		353,353		56,502
Purchases of other investments	-119,815		-38,492		-491,210
Decrease (increase) in securities lending collateral	2,922		-3,167		7,771
Redemption from operating affiliates	77,544		86,657		0
Decrease (increase) in restricted cash	27,489		-172,962		-3,493
Proceeds on sale of subsidiary, net of cash	16,459		21,388		0
Purchase of subsidiary, net of cash acquired	-643,545		0		17,196
Return of capital from subsidiaries	0
Investment in subsidiaries	0				0
Net cash provided by (used in) investing activities	121,582		-321,436		-302,214
Cash flows provided by (used in) financing activities
Proceeds on issuance of notes payable to operating affiliates	680,027		442,412		0
Repayments on notes payable to operating affiliates	-617,068		-3,553		0
Issuance of common shares, net	5,347		1,211		3,015
Purchases of common shares under share repurchase program	-510,952		-513,504		-259,962
Dividends paid	-117,043		-360,071		-110,037
(Decrease) increase in securities lending payable	-2,922		3,167		-7,771
Third party investment in redeemable noncontrolling interest	68,200		92,190		0
Third party redemption of redeemable noncontrolling interest	-10,496		-19,400		0
Investment in third party noncontrolling interest	0		58,500		450,100
Third party subscriptions received in advance	15,400		35,000		19,400
Return of capital to parent	0
Capital contribution from parent	0				0
Third party subscriptions received in advance					19,400
Net cash (used in) provided by financing activities	-489,507		-264,048		94,745
Effect of foreign currency rate changes on cash and cash equivalents	-30,764		-6,364		17,540
Net increase (decrease) in cash	-156,908		-326,574		353,236
Cash and cash equivalents, beginning of year	734,148		1,060,722		707,486
Cash and cash equivalents, end of year	577,240		734,148		1,060,722
Consolidating Adjustments
Condensed Consolidating Statement Of Cash Flows, Captions [Line Items]
Net cash (used in) provided by operating activities	-100,000	[1]	-1,009,000	[1]	-734,000	[1]
Cash flows provided by (used in) investing activities
Proceeds on sales of investments	0	[1]	0	[1]	0	[1]
Proceeds on maturities of investments	0	[1]	0	[1]	0	[1]
Purchases of fixed maturities	0	[1]	0	[1]	0	[1]
(Purchases) sales of short-term investments, net	0	[1]	0	[1]	0	[1]
Purchases of other investments	0	[1]	0	[1]	0	[1]
Decrease (increase) in securities lending collateral	0	[1]	0	[1]	0	[1]
Redemption from operating affiliates	0	[1]	0	[1]
Decrease (increase) in restricted cash	0	[1]	0	[1]	0	[1]
Proceeds on sale of subsidiary, net of cash	0	[1]	0	[1]
Purchase of subsidiary, net of cash acquired	0	[1]			0	[1]
Return of capital from subsidiaries	-673,966	[1]
Investment in subsidiaries	480,000	[1]			-166,582	[1]
Net cash provided by (used in) investing activities	-193,966	[1]	0	[1]	166,582	[1]
Cash flows provided by (used in) financing activities
Proceeds on issuance of notes payable to operating affiliates	0	[1]	0	[1]
Repayments on notes payable to operating affiliates	0	[1]	0	[1]
Issuance of common shares, net	0	[1]	0	[1]	0	[1]
Purchases of common shares under share repurchase program	0	[1]	0	[1]	0	[1]
Dividends paid	100,000	[1]	1,009,000	[1]	734,000	[1]
(Decrease) increase in securities lending payable	0	[1]	0	[1]	0	[1]
Third party investment in redeemable noncontrolling interest	0	[1]	0	[1]
Third party redemption of redeemable noncontrolling interest	0	[1]	0	[1]
Investment in third party noncontrolling interest			0	[1]	0	[1]
Third party subscriptions received in advance	0	[1]	0	[1]
Return of capital to parent	673,966	[1]
Capital contribution from parent	-480,000	[1]			-166,582	[1]
Third party subscriptions received in advance					0	[1]
Net cash (used in) provided by financing activities	293,966	[1]	1,009,000	[1]	567,418	[1]
Effect of foreign currency rate changes on cash and cash equivalents	0	[1]	0	[1]	0	[1]
Net increase (decrease) in cash	0	[1]	0	[1]	0	[1]
Cash and cash equivalents, beginning of year	0	[1]	0	[1]	0	[1]
Cash and cash equivalents, end of year	0	[1]	0	[1]	0	[1]
Validus Holdings, Ltd. (Parent Guarantor)
Condensed Consolidating Statement Of Cash Flows, Captions [Line Items]
Net cash (used in) provided by operating activities	-41,905		873,083		548,288
Cash flows provided by (used in) investing activities
Proceeds on sales of investments	0		0		0
Proceeds on maturities of investments	0		0		0
Purchases of fixed maturities	0		0		0
(Purchases) sales of short-term investments, net	0		0		0
Purchases of other investments	0		0		0
Decrease (increase) in securities lending collateral	0		0		0
Redemption from operating affiliates	0		0
Decrease (increase) in restricted cash	0		0		0
Proceeds on sale of subsidiary, net of cash	0		0
Purchase of subsidiary, net of cash acquired	0				0
Return of capital from subsidiaries	673,966
Investment in subsidiaries	0				166,582
Net cash provided by (used in) investing activities	673,966		0		-166,582
Cash flows provided by (used in) financing activities
Proceeds on issuance of notes payable to operating affiliates	0		0
Repayments on notes payable to operating affiliates	0		0
Issuance of common shares, net	5,347		1,211		3,015
Purchases of common shares under share repurchase program	-510,952		-513,504		-259,962
Dividends paid	-117,043		-360,071		-110,037
(Decrease) increase in securities lending payable	0		0		0
Third party investment in redeemable noncontrolling interest	0		0
Third party redemption of redeemable noncontrolling interest	0		0
Investment in third party noncontrolling interest			0		0
Third party subscriptions received in advance	0		0
Return of capital to parent	0
Capital contribution from parent	0				0
Third party subscriptions received in advance					0
Net cash (used in) provided by financing activities	-622,648		-872,364		-366,984
Effect of foreign currency rate changes on cash and cash equivalents	0		0		0
Net increase (decrease) in cash	9,413		719		14,722
Cash and cash equivalents, beginning of year	20,385		19,666		4,944
Cash and cash equivalents, end of year	29,798		20,385		19,666
Validus Holdings (UK) plc (Subsidiary Issuer)
Condensed Consolidating Statement Of Cash Flows, Captions [Line Items]
Net cash (used in) provided by operating activities	81		0		0
Cash flows provided by (used in) investing activities
Proceeds on sales of investments	0		0		0
Proceeds on maturities of investments	0		0		0
Purchases of fixed maturities	0		0		0
(Purchases) sales of short-term investments, net	0		0		0
Purchases of other investments	0		0		0
Decrease (increase) in securities lending collateral	0		0		0
Redemption from operating affiliates	0		0
Decrease (increase) in restricted cash	0		0		0
Proceeds on sale of subsidiary, net of cash	0		0
Purchase of subsidiary, net of cash acquired	0				0
Return of capital from subsidiaries	0
Investment in subsidiaries	-240,000				0
Net cash provided by (used in) investing activities	-240,000		0		0
Cash flows provided by (used in) financing activities
Proceeds on issuance of notes payable to operating affiliates	0		0
Repayments on notes payable to operating affiliates	0		0
Issuance of common shares, net	0		0		0
Purchases of common shares under share repurchase program	0		0		0
Dividends paid	0		0		0
(Decrease) increase in securities lending payable	0		0		0
Third party investment in redeemable noncontrolling interest	0		0
Third party redemption of redeemable noncontrolling interest	0		0
Investment in third party noncontrolling interest			0		0
Third party subscriptions received in advance	0		0
Return of capital to parent	0
Capital contribution from parent	240,000				0
Third party subscriptions received in advance					0
Net cash (used in) provided by financing activities	240,000		0		0
Effect of foreign currency rate changes on cash and cash equivalents	0		0		0
Net increase (decrease) in cash	81		0		0
Cash and cash equivalents, beginning of year	0		0		0
Cash and cash equivalents, end of year	81		0		0
Other Validus Holdings, Ltd. Subsidiaries (Non-guarantor Subsidiaries)
Condensed Consolidating Statement Of Cash Flows, Captions [Line Items]
Net cash (used in) provided by operating activities	383,605	[2]	401,191	[2]	728,877	[2]
Cash flows provided by (used in) investing activities
Proceeds on sales of investments	4,756,555	[2]	4,370,548	[2]	3,393,740	[2]
Proceeds on maturities of investments	554,619	[2]	490,459	[2]	548,226	[2]
Purchases of fixed maturities	-4,379,314	[2]	-5,392,728	[2]	-3,726,611	[2]
(Purchases) sales of short-term investments, net	-121,264	[2]	353,353	[2]	56,502	[2]
Purchases of other investments	-119,815	[2]	-38,492	[2]	-491,210	[2]
Decrease (increase) in securities lending collateral	2,922	[2]	-3,167	[2]	7,771	[2]
Redemption from operating affiliates	77,544	[2]	86,657	[2]
Decrease (increase) in restricted cash	27,489	[2]	-172,962	[2]	-3,493	[2]
Proceeds on sale of subsidiary, net of cash	16,459	[2]	21,388	[2]
Purchase of subsidiary, net of cash acquired	-643,545	[2]			17,196	[2]
Return of capital from subsidiaries	0	[2]
Investment in subsidiaries	-240,000	[2]			0	[2]
Net cash provided by (used in) investing activities	-118,418	[2]	-321,436	[2]	-302,214	[2]
Cash flows provided by (used in) financing activities
Proceeds on issuance of notes payable to operating affiliates	680,027	[2]	442,412	[2]
Repayments on notes payable to operating affiliates	-617,068	[2]	-3,553	[2]
Issuance of common shares, net	0	[2]	0	[2]	0	[2]
Purchases of common shares under share repurchase program	0	[2]	0	[2]	0	[2]
Dividends paid	-100,000	[2]	-1,009,000	[2]	-734,000	[2]
(Decrease) increase in securities lending payable	-2,922	[2]	3,167	[2]	-7,771	[2]
Third party investment in redeemable noncontrolling interest	68,200	[2]	92,190	[2]
Third party redemption of redeemable noncontrolling interest	-10,496	[2]	-19,400	[2]
Investment in third party noncontrolling interest			58,500	[2]	450,100	[2]
Third party subscriptions received in advance	15,400	[2]	35,000	[2]
Return of capital to parent	-673,966	[2]
Capital contribution from parent	240,000	[2]			166,582	[2]
Third party subscriptions received in advance					19,400	[2]
Net cash (used in) provided by financing activities	-400,825	[2]	-400,684	[2]	-105,689	[2]
Effect of foreign currency rate changes on cash and cash equivalents	-30,764	[2]	-6,364	[2]	17,540	[2]
Net increase (decrease) in cash	-166,402	[2]	-327,293	[2]	338,514	[2]
Cash and cash equivalents, beginning of year	713,763	[2]	1,041,056	[2]	702,542	[2]
Cash and cash equivalents, end of year	547,361	[2]	713,763	[2]	1,041,056	[2]
Operating Affiliates [Member]
Cash flows provided by (used in) investing activities
Investments in affiliates	-37,600		-22,000		-91,500
Operating Affiliates [Member] | Consolidating Adjustments
Cash flows provided by (used in) investing activities
Investments in affiliates	0	[1]	0	[1]	0	[1]
Operating Affiliates [Member] | Validus Holdings, Ltd. (Parent Guarantor)
Cash flows provided by (used in) investing activities
Investments in affiliates	0		0		0
Operating Affiliates [Member] | Validus Holdings (UK) plc (Subsidiary Issuer)
Cash flows provided by (used in) investing activities
Investments in affiliates	0		0		0
Operating Affiliates [Member] | Other Validus Holdings, Ltd. Subsidiaries (Non-guarantor Subsidiaries)
Cash flows provided by (used in) investing activities
Investments in affiliates	-37,600	[2]	-22,000	[2]	-91,500	[2]
Investment Affiliates [Member]
Cash flows provided by (used in) investing activities
Investments in affiliates	-12,468		-14,492		-12,835
Investment Affiliates [Member] | Consolidating Adjustments
Cash flows provided by (used in) investing activities
Investments in affiliates	0	[1]	0	[1]	0	[1]
Investment Affiliates [Member] | Validus Holdings, Ltd. (Parent Guarantor)
Cash flows provided by (used in) investing activities
Investments in affiliates	0		0		0
Investment Affiliates [Member] | Validus Holdings (UK) plc (Subsidiary Issuer)
Cash flows provided by (used in) investing activities
Investments in affiliates	0		0		0
Investment Affiliates [Member] | Other Validus Holdings, Ltd. Subsidiaries (Non-guarantor Subsidiaries)
Cash flows provided by (used in) investing activities
Investments in affiliates	($12,468)	[2]	($14,492)	[2]	($12,835)	[2]
[1]	Amounts include consolidating adjustments between the Parent Guarantor, the Subsidiary Issuer and the non-guarantor subsidiaries.
[2]	Amounts include an aggregation of the non-guarantor subsidiaries and include consolidating adjustments between these subsidiaries.