ICON Public Limited (ICLR) 20-F 28 Feb 17 2016 FY Annual report (foreign) Financial data

Document and Entity Information

Document and Entity Information	12 Months Ended
	Dec. 31, 2016shares
Document Information [Line Items]
Document Type	20-F
Amendment Flag	false
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	FY
Trading Symbol	ICLR
Entity Registrant Name	ICON PLC
Entity Central Index Key	1,060,955
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding	54,530,843

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	[1]
Current Assets:
Cash and cash equivalents	$ 192,541	$ 103,911
Short term investments - available for sale (Note 3)	68,046	85,990
Accounts receivable, net	416,229	409,165
Unbilled revenue	192,687	173,649
Other receivables	32,044	30,935
Prepayments and other current assets	35,170	36,128
Income taxes receivable (Note 13)	21,241	22,961
Total current assets	957,958	862,739
Other Assets:
Property, plant and equipment, net (Note 6)	148,967	150,218
Goodwill (Note 4)	616,088	588,434
Non-current other assets	13,831	11,591
Non-current income taxes receivable (Note 13)	12,698	11,362
Non-current deferred tax asset (Note 13)	19,691	26,738
Intangible assets (Note 5)	56,610	66,127
Total Assets	1,825,843	1,717,209	[2]
Current Liabilities:
Accounts payable	8,696	7,021
Payments on account	272,757	318,697
Other liabilities (Note 7)	190,727	231,879
Income taxes payable (Note 13)	22,226	14,203
Total current liabilities	494,406	571,800
Other Liabilities:
Non-current bank credit lines and loan facilities (Note 20)	348,511	348,306
Non-current other liabilities (Note 8)	23,752	12,224
Non-current government grants (Note 11)	887	959
Non-current income taxes payable (Note 13)	8,482	16,180
Non-current deferred tax liability (Note 13)	4,631	4,644
Commitments and contingencies (Note 16)
Total Liabilities	880,669	954,113
Shareholders' Equity:
Ordinary shares, par value 6 euro cents per share; 100,000,000 shares authorized, (Note 12) 54,530,843 shares issued and outstanding at December 31, 2016 and 54,958,912 shares issued and outstanding at December 31, 2015.	4,611	4,679
Additional paid-in capital	438,207	383,395
Capital redemption reserve (Note 12 (a))	809	715
Accumulated other comprehensive income (Note 19)	(86,300)	(61,636)
Retained earnings	587,847	435,943
Total Shareholders' Equity	945,174	763,096
Total Liabilities and Shareholders' Equity	$ 1,825,843	$ 1,717,209
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).
[2]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs.

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - € / shares	Dec. 31, 2016	Dec. 31, 2015	[1]
Ordinary shares, par value	€ 0.06	€ 0.06
Ordinary shares, shares authorized	100,000,000	100,000,000
Ordinary shares, shares issued	54,530,843	54,958,912
Ordinary shares, shares outstanding	54,530,843	54,958,912
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenue:
Gross revenue	$ 2,364,956	$ 2,161,618	$ 2,030,286
Reimbursable expenses	(698,469)	(586,640)	(526,970)
Net revenue	1,666,487	1,574,978	1,503,316
Costs and expenses:
Direct costs	961,333	908,979	903,167
Selling, general and administrative	325,726	326,786	336,461
Depreciation and amortization	59,575	57,677	52,542
Restructuring and other items, net (Note 14)	8,159		8,796
Total costs and expenses	1,354,793	1,293,442	1,300,966
Income from operations	311,694	281,536	202,350
Interest income	1,484	1,306	1,151
Interest expense	(13,006)	(3,992)	(785)
Income before provision for income taxes	300,172	278,850	202,716
Provision for income taxes (Note 13)	(37,993)	(39,311)	(30,248)
Net income	$ 262,179	$ 239,539	$ 172,468
Net income per ordinary share:
Basic	$ 4.75	$ 4.08	$ 2.80
Diluted	$ 4.65	$ 3.97	$ 2.73
Weighted average number of ordinary shares outstanding:
Basic (Note 2 (u))	55,248,900	58,746,935	61,496,115
Diluted (Note 2 (u))	56,407,136	60,290,033	63,131,417

Consolidated Statements Of Comp

Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net income	$ 262,179	$ 239,539	$ 172,468
Currency translation adjustment	(12,839)	(35,105)	(45,038)
Currency impact of long-term funding	(8,824)	7,342	9,806
Income tax on currency impact of long term funding	396	(3,574)	(178)
Unrealized capital gain/(loss) - investments	11	(54)	20
Actuarial (loss)/gain on defined benefit pension plan	(2,485)	2,693	(4,125)
Realized (loss)/gain on interest rate hedge	(923)	4,617
Total comprehensive income	$ 237,515	$ 215,458	$ 132,953

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity and Comprehensive Income - USD ($) $ in Thousands	Total		Ordinary Shares	Additional Paid-in Capital	Capital Redemption Reserve	Accumulated Other Comprehensive Income	Retained Earnings
Balance (in shares) at Dec. 31, 2013			61,587,257
Balance at Dec. 31, 2013	$ 910,579		$ 5,168	$ 279,572	$ 100	$ 1,960	$ 623,779
Comprehensive Income:
Net income	172,468						172,468
Currency translation adjustment	(45,038)					(45,038)
Currency impact of long-term funding	9,806					9,806
Income tax on currency impact of long- term funding	(178)					(178)
Unrealized capital gain (loss) - investments	20					20
Actuarial gain (loss) on defined benefit pension plan	(4,125)					(4,125)
Total comprehensive income	132,953
Exercise of share options (in shares)			926,407
Exercise of share options	22,256		$ 74	22,182
Issue of restricted share units / performance share units (in shares)			233,726
Issue of restricted share units / performance share units	18			18
Share based compensation expense	23,078			23,078
Share issue costs	(20)			(20)
Repurchase of ordinary shares (in shares)			(2,640,610)
Repurchase of ordinary shares	(140,030)		$ (205)		205		(140,030)
Share repurchase costs	(1,032)						(1,032)
Excess income tax benefit on exercise of equity compensation (net of deferred tax)	2,404			2,404
Balance (in shares) at Dec. 31, 2014			60,106,780
Balance at Dec. 31, 2014	950,206		$ 5,037	327,234	305	(37,555)	655,185
Comprehensive Income:
Net income	239,539						239,539
Currency translation adjustment	(35,105)					(35,105)
Currency impact of long-term funding	7,342					7,342
Income tax on currency impact of long- term funding	(3,574)					(3,574)
Unrealized capital gain (loss) - investments	(54)					(54)
Actuarial gain (loss) on defined benefit pension plan	2,693					2,693
Gain on interest rate hedge	4,617					4,617
Total comprehensive income	215,458
Exercise of share options (in shares)			773,753
Exercise of share options	20,981		$ 52	20,929
Issue of restricted share units / performance share units (in shares)			276,860
Issue of restricted share units / performance share units	18			18
Share based compensation expense	33,317			33,317
Share issue costs	(8)			(8)
Repurchase of ordinary shares (in shares)			(6,198,481)
Repurchase of ordinary shares	(457,892)		$ (410)		410		(457,892)
Share repurchase costs	(889)						(889)
Excess income tax benefit on exercise of equity compensation (net of deferred tax)	$ 1,905			1,905
Balance (in shares) at Dec. 31, 2015	54,958,912	[1]	54,958,912
Balance at Dec. 31, 2015	$ 763,096	[1]	$ 4,679	383,395	715	(61,636)	435,943
Comprehensive Income:
Net income	262,179						262,179
Currency translation adjustment	(12,839)					(12,839)
Currency impact of long-term funding	(8,824)					(8,824)
Income tax on currency impact of long- term funding	396					396
Unrealized capital gain (loss) - investments	11					11
Actuarial gain (loss) on defined benefit pension plan	(2,485)					(2,485)
Amortization of interest rate hedge	(923)					(923)
Total comprehensive income	237,515
Exercise of share options (in shares)			393,240
Exercise of share options	10,139		$ 26	10,113
Issue of restricted share units / performance share units (in shares)			607,878
Issue of restricted share units / performance share units	41			41
Share based compensation expense	40,343			40,343
Share issue costs	(17)			(17)
Repurchase of ordinary shares (in shares)			(1,429,187)
Repurchase of ordinary shares	(110,000)		$ (94)		94		(110,000)
Share repurchase costs	(275)						(275)
Excess income tax benefit on exercise of equity compensation (net of deferred tax)	$ 4,332			4,332
Balance (in shares) at Dec. 31, 2016	54,530,843		54,530,843
Balance at Dec. 31, 2016	$ 945,174		$ 4,611	$ 438,207	$ 809	$ (86,300)	$ 587,847
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016		Dec. 31, 2015		Dec. 31, 2014
Cash flows from operating activities:
Net income	$ 262,179		$ 239,539		$ 172,468
Adjustments to reconcile net income to net cash provided by operating activities:
Loss on disposal of property, plant and equipment	151		55		248
Depreciation expense	42,125		40,210		42,200
Amortization of intangibles	17,450		17,467		10,342
Amortization of government grants	(44)		53		(213)
Interest on short term investments	(823)		(571)		(910)
Realized (gain)/loss on sale of short term investments	(50)		113
Amortization of gain on interest rate hedge	(923)		(41)
Amortization of financing costs	566
Stock compensation expense	40,343		33,317		22,742
Deferred taxes	1,545		3,157		(7,900)
Changes in assets and liabilities:
Decrease/(increase) in accounts receivable	2,526		(18,671)		(7,032)
Increase in unbilled revenue	(16,753)		(29,281)		(13,671)
Increase in other receivables	(1,829)		(14,519)		(4,259)
Decrease/(increase) in prepayments and other current assets	1,872		(8,631)		(3,574)
Increase in other non-current assets	(2,157)		(55)		(2,264)
(Decrease)/increase in payments on account	(45,754)		34,644		(47,548)
(Decrease)/increase in other current liabilities	(44,713)		(26,266)		15,111
Increase in other non-current liabilities	3,008		6,378		1,283
(Decrease)/increase in income taxes payable	(690)		(949)		3,021
Increase/(decrease) in accounts payable	1,175		3,124		(11,006)
Net cash provided by operating activities	259,204		279,073		169,038
Cash flows from investing activities:
Purchase of property, plant and equipment	(42,601)		(49,730)		(32,779)
Purchase of subsidiary undertakings and acquisition costs	(54,209)		(166,292)		(124,301)
Cash acquired with subsidiary undertaking	3,168		194		3,527
Sale of short term investments	40,858		25,708		103,475
Purchase of short term investments	(22,030)		(14,194)		(61,328)
Net cash used in investing activities	(74,814)		(204,314)		(111,406)
Cash flows from financing activities:
Drawdown of credit lines and facilities	73,000		851,500
Repayment of credit lines and facilities	(73,000)		(501,500)
Proceeds from the exercise of equity compensation	10,180		20,999		22,274
Share issue costs	(17)		(8)		(20)
Excess tax benefit on exercise of equity compensation	6,402		1,905		2,404
Repurchase of ordinary shares	(110,000)		(457,892)		(140,030)
Share repurchase costs	(275)		(889)		(1,032)
Repayment of government grant			(159)
Proceeds from interest rate hedge			4,658
Net cash used in financing activities	(93,710)		(81,386)		(116,404)
Effect of exchange rate movements on cash	(2,050)		(8,362)		(4,847)
Net increase/(decrease) in cash and cash equivalents	88,630		(14,989)		(63,619)
Cash and cash equivalents at beginning of year	103,911	[1]	118,900		182,519
Cash and cash equivalents at end of year	$ 192,541		$ 103,911	[1]	$ 118,900
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).

Description of business

Description of business	12 Months Ended
	Dec. 31, 2016
Description of business	1. Description of business ICON plc and its subsidiaries ("the Company" or "ICON") is a contract research organization ("CRO"), providing outsourced development services on a global basis to the pharmaceutical, biotechnology and medical device industries. We specialize in the strategic development, management and analysis of programs that support all stages of the clinical development process from compound selection to Phase I-IV clinical studies. Our vision is to be the Global CRO partner of choice in drug development by delivering best in class information, solutions and performance in clinical and outcomes research. We believe that we are one of a select group of CROs with the expertise and capability to conduct clinical trials in most major therapeutic areas on a global basis and have the operational flexibility to provide development services on a stand-alone basis or as part of an integrated "full service" solution. At December 31, 2016 we had approximately 12,500 employees, in 87 locations in 38 countries. During the year ended December 31, 2016, we derived approximately 45.8%, 43.4% and 10.8% of our net revenue in the United States, Europe and Rest of World, respectively. We began operations in 1990 and have expanded our business predominately through internal growth, together with a number of strategic acquisitions to enhance our capabilities and expertise in certain areas of the clinical development process. We are incorporated in Ireland and our principal executive office is located at: South County Business Park, Leopardstown, Dublin 18, Republic of Ireland. The contact telephone number of this office is +353 1 2912000.

Significant Accounting Policies

Significant Accounting Policies	12 Months Ended
	Dec. 31, 2016
Significant Accounting Policies	2. Significant Accounting Policies The accounting policies noted below were applied in the preparation of the accompanying financial statements of the Company and are in conformity with accounting principles generally accepted in the United States. (a) Basis of consolidation The consolidated financial statements include the financial statements of the Company and all of its subsidiaries. All significant intercompany profits, transactions and account balances have been eliminated. The results of subsidiary undertakings acquired in the period are included in the consolidated statement of operations from the date of acquisition. (b) Use of estimates The preparation of financial statements in conformity with generally accepted accounting principles in the United States requires management to make estimates and judgments 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 reported period. Actual results could differ from those estimates. The principle management estimates and judgments used in preparing the financial statements relate to revenue recognition, taxation, goodwill and business combinations. (c) Revenue recognition The Company primarily earns revenues by providing a number of different services to its customers. These services, which are integral elements of the clinical development process, include clinical trials management, biometric activities, consulting, imaging, contract staffing, informatics and laboratory services. Contracts range in duration from a number of months to several years. Revenue for services, as rendered, is recognized only after persuasive evidence of an arrangement exists, the sales price is fixed or determinable and collectability is reasonably assured. Clinical trials management revenue is recognized on a proportional performance method. Depending on the contractual terms revenue is either recognized on the percentage of completion method based on the relationship between hours incurred and the total estimated hours of the trial or on the unit of delivery method. Contract costs equate to the product of labor hours incurred and compensation rates. For the percentage of completion method, the input (effort expended) method has been used to measure progress towards completion as there is a direct relationship between input and productivity. Contract revenue is the product of the aggregated labor hours required to complete the specified contract tasks at the agreed contract rates. The Company regularly reviews the estimate of total contract time to ensure such estimates remain appropriate taking into account actual contract stage of completion, remaining time to complete and any identified changes to the contract scope. Remaining time to complete depends on the specific contract tasks, the complexity of the contract and can include geographical site selection and initiation, patient enrollment, patient testing and level of results analysis required. While the Company may routinely adjust time estimates, the Company's estimates and assumptions historically have been accurate in all material respects in the aggregate. Where revenue is recognized on the unit of delivery method, the basis applied is the number of units completed as a percentage of the total number of contractual units. Biometrics revenue is recognized on a fee-for-service method as each unit of data is prepared on the basis of the number of units completed in a period as a percentage of the total number of contracted units. Imaging revenue is recognized on a fee-for-service basis recognizing revenue for each image completed. Consulting revenue is recognized on a fee-for-service basis as each hour of the related service is performed. Contract staffing revenue is recognized on a fee-for-service basis, over the time the related service is performed, or in the case of permanent placement, once the candidate has been placed with the client. Informatics revenue is recognized on a fee-for-service basis. Laboratory service revenue is recognized on a fee-for-service basis. The Company accounts for laboratory service contracts as multiple element arrangements, with contractual elements comprising laboratory kits and laboratory testing, each of which can be sold separately. Sales prices for contractual elements are determined by reference to objective and reliable evidence of their sales price. Revenues for contractual elements are recognized on the basis of the number of deliverable units completed in the period. Contracts generally contain provisions for renegotiation in the event of changes in the scope, nature, duration, or volume of services of the contract. Renegotiated amounts are recognized as revenue by revision to the total contract value arising as a result of an authorized customer change order. The difference between the amount of revenue recognized and the amount billed on a particular contract is included in the balance sheet as unbilled revenue or payments on account. Normally, amounts become billable upon the achievement of certain milestones, for example, target patient enrolment rates, clinical testing sites initiated or case report forms completed. Once the milestone target is reached, amounts become billable in accordance with pre-agreed payment schedules included in the contract or on submission of appropriate billing detail. Such cash payments are not representative of revenue earned on the contract as revenues are recognized over the period in which the specified contractual obligations are fulfilled. Amounts included in unbilled revenue are expected to be collected within one year and are included within current assets. Advance billings to customers, for which revenue has not been recognized, are recognized as payments on account within current liabilities. In the event of contract termination, if the value of work performed and recognized as revenue is greater than aggregate milestone billings at the date of termination, cancellation clauses usually ensure that the Company is paid for all work performed to the termination date. (d) Reimbursable expenses Reimbursable expenses comprise investigator payments and certain other costs which are reimbursed by clients under terms specific to each contract and are deducted from gross revenue in arriving at net revenue. Investigator payments are accrued based on patient enrollment over the life of the contract. Investigator payments are made based on predetermined contractual arrangements, which may differ from the accrual of the expense. (e) Direct costs Direct costs consist of compensation, associated employee benefits and share-based payments for project-related employees and other direct project-related costs. (f) Advertising costs All costs associated with advertising and promotion are expensed as incurred. The advertising and promotion costs were $7,167,050, $4,513,750 and $3,563,900 for the years ended December 31, 2016, December 31, 2015 and December 31, 2014 respectively. (g) Foreign currencies and translation of subsidiaries The Company's financial statements are prepared in United States dollars. Transactions in currencies other than United States dollars are recorded at the rate ruling at the date of the transaction. Monetary assets and liabilities denominated in currencies other than United States dollars are translated into United States dollars at exchange rates prevailing at the balance sheet date. Adjustments resulting from these translations are charged or credited to income. Amounts charged or credited to the statement of operations for the years ended December 31, 2016, December 31, 2015 and December 31, 2014 were as follows: Year ended December 31, (in thousands) 2016 2015 2014 Amounts charged/(credited) $ 2,094 $ (3,608 ) $ (5,942 ) The financial statements of subsidiaries with other functional currencies are translated at period end rates for the balance sheet and average rates for the statement of operations. Translation gains and losses arising are reported as a movement on accumulated other comprehensive income. (h) Disclosure about fair value of financial instruments The following methods and assumptions were used to estimate the fair value of each material class of financial instrument: Cash, cash equivalents, unbilled revenue, other receivables, short term investments, prepayments and other current assets, accounts receivable, accounts payable, investigator payments, payments on account, accrued liabilities, accrued bonuses and income taxes payable have carrying amounts that approximate fair value due to the short term maturities of these instruments. Other liabilities' carrying amounts approximate fair value based on net present value of estimated future cash flows. Financial instruments are measured in the statement of financial position at fair value using a fair value hierarchy of valuation inputs. The hierarchy prioritizes the inputs into three levels based on the extent to which inputs used in measuring fair value are observable in the market. Each fair value measurement is reported in one of three levels, which is determined by the lowest level input that is significant to the fair value measurement in its entirety. These levels are: Level 1: Inputs are based upon unadjusted quoted prices for identical instruments traded in active markets. Level 2: Inputs are based upon quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active and model-based valuation techniques for which all significant assumptions are observable in the market or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3: Inputs are generally unobservable and typically reflect management’s estimates of assumptions that market participants would use in pricing the asset or liability. The Company classifies its short term investments as available for sale, as it does not actively trade such securities nor does it intend to hold them to maturity. The fair value of short term investments are represented by level 1 fair value measurements – quoted prices in active markets for identical assets. The unrealized movements in fair value are recognized in equity until disposal or sale, at which time, those unrealized movements from prior periods are recognized in profit or loss. For losses other than temporary, which reduce the carrying amount below cost is recognized in profit or loss. (i) Business combinations The cost of a business combination is measured as the aggregate of the fair values at the date of exchange of assets given, liabilities incurred or assumed and equity instruments issued in exchange for control. Where a business combination agreement provides for an adjustment to the cost of the acquisition which is contingent upon future events, the amount of the estimated adjustment is recognized at the acquisition date at the fair value of the contingent consideration. Any changes to this estimate outside the measurement period will depend on the classification of the contingent consideration. If the contingent consideration is classified as equity it shall not be re-measured and the settlement shall be accounted for within equity. If the contingent consideration is classified as a liability any adjustments will be accounted for through the Consolidated Statement of Operations or Other Comprehensive Income depending on whether the liability is considered a financial instrument. The assets, liabilities and contingent liabilities of businesses acquired are measured at their fair values at the date of acquisition. In the case of a business combination which is completed in stages, the fair values of the identifiable assets, liabilities and contingent liabilities are determined at the date of each exchange transaction. When the initial accounting for a business combination is determined provisionally, any subsequent adjustments to the provisional values allocated to the identifiable assets, liabilities and contingent liabilities are made within twelve months of the acquisition date and presented as adjustments to goodwill in the reporting period in which the adjustments are determined. (j) Goodwill and Impairment Goodwill represents the excess of the cost of acquired entities over the net amounts assigned to assets acquired and liabilities assumed. Goodwill primarily comprises acquired workforce in place which does not qualify for recognition as an asset apart from goodwill. Goodwill is stated net of any provision for impairment. The Company tests goodwill annually for any impairments or whenever events occur which may indicate impairment. The first step is to compare the carrying amount of the reporting unit's assets to the fair value of the reporting unit. If the carrying amount exceeds the fair value then a second step is completed which involves the fair value of the reporting unit being allocated to each asset and liability with the excess being implied goodwill. The impairment loss is the amount by which the recorded goodwill exceeds the implied goodwill. No impairment was recognized as a result of the impairment testing carried out for the years ended December 31, 2016, December 31, 2015 and December 31, 2014. (k) Intangible assets Intangible assets are amortized on a straight line basis over their estimated useful life. (l) Cash and cash equivalents Cash and cash equivalents include cash and highly liquid investments with initial maturities of three months or less and are stated at cost, which approximates market value. (m) Short term investments - available for sale The Company classifies short-term investments as available for sale in accordance with the terms of FASB ASC 320, Investments – Debt and Equity Securities (n) Inventory Inventory is valued at the lower of cost and market value and after provisions for obsolescence. The cost of inventories comprises the purchase price and attributable costs, less trade discounts. At December 31, 2016 the carrying value of inventory, included within prepayments and other current assets on the balance sheet, was $2.4 million (2015: $1.8 million). (o) Property, plant and equipment Property, plant and equipment is stated at cost less accumulated depreciation. Depreciation of property, plant and equipment is computed using the straight line method based on the estimated useful lives of the assets as listed below: Years Building 40 Computer equipment and software 2-8 Office furniture and fixtures 8 Laboratory equipment 5 Motor vehicles 5 Leasehold improvements are amortized using the straight-line method over the estimated useful life of the asset or the lease term, whichever is shorter. (p) Leased assets Costs in respect of operating leases are charged to the statement of operations on a straight line basis over the lease term. Assets acquired under capital finance leases are included in the balance sheet at the present value of the future minimum lease payments and are depreciated over the shorter of the lease term and their remaining useful lives. The corresponding liabilities are recorded in the balance sheet and the interest element of the capital lease rental is charged to interest expense. (q) Income taxes The Company applies the asset and liability method of accounting for income taxes. Under the asset and liability method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which these temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. The Company recognizes the effect of income tax positions only if those positions will more likely than not be sustained. Recognized income tax positions are measured at the largest amount of tax benefit that is greater than 50 percent likely of being realized upon settlement. Interest and penalties related to income taxes are included in income tax expense and classified with the related liability on the consolidated balance sheet. On November 21, 2015 FASB issued ASU 2015-17 on the balance sheet classification of deferred taxes. The new standard requires that all deferred taxes are presented as non-current in a classified Statement of Financial Position. The new guidance is effective for public business entities for annual periods beginning after December 15, 2016 and for non-public business entities for annual periods beginning after December 15, 2017. Early adoption is available for all entities for any set of financial statements that had not been released as at November 21, 2015 with an option to apply on either a prospective or a retrospective basis. The Company elected for early adoption of ASU 2015 – 17 on a prospective basis for all financial statements issued after November 21, 2015. The effect of this is that all deferred tax assets and liabilities are classified as non-current assets and liabilities in the December 31, 2016 and December 31, 2015 balance sheets. (r) Government grants Government grants received relating to capital expenditures are shown as deferred income and credited to income on a basis consistent with the depreciation policy of the relevant assets. Grants relating to categories of operating expenditures are credited to income in the period in which the expenditure to which they relate is charged. Under the grant agreements amounts received may become repayable in full should certain circumstances specified within the grant agreements occur, including downsizing by the Company, disposing of the related assets, ceasing to carry on its business or the appointment of a receiver over any of its assets. The Company has not recognized any loss contingency having assessed as remote the likelihood of these events arising. (s) Research and development credits Research and development credits are available to the Company under the tax laws in certain jurisdictions, based on qualifying research and development spend as defined under those tax laws. Research and development credits are generally recognized as a reduction of income tax expense. However, certain tax jurisdictions provide refundable credits that are not wholly dependent on the Company's ongoing income tax status or income tax position. In these circumstances the benefit of these credits is not recorded as a reduction to income tax expense, but rather as a reduction of operating expenditure. (t) Pension costs The Company contributes to defined contribution plans covering all eligible employees. The Company contributes to these plans based upon various fixed percentages of employee compensation and such contributions are expensed as incurred. The Company operates, through a subsidiary, a defined benefit plan for certain of its United Kingdom and Swiss employees. The Company accounts for the costs of these plans using actuarial models required by FASB ASC 715-30 and these plans are presented in accordance with the requirements of FASB ASC 715-60 Defined Benefit Plans – Other Post retirement (u) Net income per ordinary share Basic net income per ordinary share has been computed by dividing net income available to ordinary shareholders by the weighted average number of ordinary shares outstanding during the period. Diluted net income per ordinary share is computed by adjusting the weighted average number of ordinary shares outstanding during the period for all potentially dilutive ordinary shares outstanding during the period and adjusting net income for any changes in income or loss that would result from the conversion of such potential ordinary shares. There is no difference in net income used for basic and diluted net income per ordinary share. The reconciliation of the number of shares used in the computation of basic and diluted net income per ordinary share is as follows: Year Ended December 31, 2016 2015 2014 Weighted average number of ordinary shares outstanding for basic net income per ordinary share 55,248,900 58,746,935 61,496,115 Effect of dilutive share options outstanding 1,158,236 1,543,098 1,635,302 Weighted average number of ordinary shares outstanding for diluted net income per ordinary share 56,407,136 60,290,033 63,131,417 (v) Share-based compensation The Company accounts for its share options, restricted share units ("RSUs") and performance share units ("PSUs") in accordance with the provisions of FASB ASC 718, Compensation – Stock Compensation. Share-based compensation expense for share options awarded to employees and Directors is estimated at the grant date based on each option's fair value as calculated using the Black-Scholes option-pricing model. Share-based compensation for RSUs and PSUs awarded to employees and Directors is calculated based on the market value of the Company's shares on the date of award of the RSUs and PSUs. The value of awards expected to vest is recognized as an expense over the requisite service periods. Forfeitures are estimated on the date of grant and revised if actual or expected forfeiture activity differs materially from original estimates. Estimating the grant date fair value of share options as of the grant date using an option-pricing model, such as the Black-Scholes model, is affected by the Company's share price as well as assumptions regarding a number of complex variables. These variables include, but are not limited to, the expected share price volatility over the term of the awards, risk-free interest rates and the expected term of the awards. (w) Impairment of long-lived assets Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of the asset to future undiscounted net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured at the amount by which the carrying amount of the asset exceeds the fair value of the asset. Assets to be disposed of are reported at the lower of the carrying amount of the asset or fair value less selling costs. (x) Derivative financial instruments We enter into transactions in the normal course of business using various financial instruments in order to hedge against exposure to fluctuating exchange and interest rates. We use derivative financial instruments to reduce exposure to fluctuations in interest rates. A derivative is a financial instrument or other contract whose value changes in response to some underlying variable, which has an initial net investment smaller than would be required for other instruments that have a similar response to the variable and that will be settled at a future date. We do not enter into derivative financial instruments for trading or speculative purposes. We did not hold any interest rate swap contracts or forward currency contracts at December 31, 2016, December 31, 2015 or December 31, 2014. Our accounting policies for derivative financial instruments are based on whether they meet the criteria for designation as cash flow or fair value hedges. A designated hedge of the exposure to variability in the future cash flows of an asset or a liability, or of a forecasted transaction, is referred to as a cash flow hedge. A designated hedge of the exposure to changes in fair value of an asset or a liability is referred to as a fair value hedge. The criterion for designating a derivative as a hedge includes the assessment of the instrument's effectiveness in risk reduction, matching of the derivative instrument to its underlying transaction and the probability that the underlying transaction will occur. For derivatives with cash flow hedge accounting designation, we report the gain or loss from the effective portion of the hedge as a component of Other Comprehensive Income and reclassify it into earnings in the same period or periods in which the hedged transaction affects earnings and within the same income statement line item as the impact of the hedged transaction. For derivatives with fair value hedge accounting designation, we recognize gains or losses from the change in fair value of these derivatives, as well as the offsetting change in the fair value of the underlying hedged item, in earnings. Fair value gains and losses arising on derivative financial instruments not qualifying for hedge accounting are reported in our Consolidated Statement of Operations. (y) Financing costs and gain on interest rate hedge The interest rate in respect of the Senior Notes is fixed at 3.64% for the five year term of the agreement. The associated interest cost is recognized in interest expense in the period since drawdown in December 2015. On October 5, 2015, the Company entered into an interest rate hedge in respect of the planned issuance of the Senior Notes in December 2015. The interest rate hedge matured on November 17, 2015 when the interest rate on the Senior Notes was fixed. The interest rate hedge was effective in accordance with Financial Accounting Standards Board ("FASB") ASC 815, "Derivatives and Hedging". The cash proceeds ($4.6 million), representing the realized gain on the interest rate hedge, were received on maturity in November 2015 and are recorded within Other Comprehensive Income. The realized gain will be amortized to the income statement, net against interest payable, over the period of the Senior Notes. Deferred financing costs (including issue costs relating to the Senior Notes) are reported at cost less accumulated amortization and the related amortization expense is included in interest expense, in our consolidated statement of income. (z) Reclassifications Certain amounts in the consolidated financial statements have been reclassified where necessary to conform to the current year presentation.

Short term investments - availa

Short term investments - available for sale	12 Months Ended
	Dec. 31, 2016
Short term investments - available for sale	3. Short term investments - available for sale December 31, December 31, 2016 2015 (in thousands) At start of year $ 85,990 $ 97,100 Purchases 22,030 14,194 Sales and maturities (40,858 ) (25,708 ) Interest on short term investments 823 571 Realized gain/(loss) on sale of short term investments 50 (113 ) Unrealized capital gain/(loss) – investments 11 (54 ) At end of year $ 68,046 $ 85,990 The Company classifies its short term investments as available for sale. Short term investments comprise highly liquid investments with maturities of greater than three months and minimum "A-" rated fixed and floating rate securities. Short term investments at December 31, 2016 have an average maturity of 1.37 years compared to 1.35 years at December 31, 2015. The investments are reported at fair value with unrealized gains or losses reported in a separate component of shareholders' equity. Any differences between the cost and fair value of investments are represented by accrued interest and unrealized gains/losses. The fair value of short term investments are represented by level 1 fair value measurements – quoted prices in active markets for identical assets. The following table represents our available for sale short term investments by major security type as of December 31, 2016: Maturity by period Cost Total Unrealized gains / (losses) Fair Value Total Less than 1 year 1 to 5 years (U.S.$ in millions) US government debt securities 13.98 (0.04 ) 13.94 3.00 10.94 Corporate securities 52.98 0.02 53.00 25.08 27.92 Term deposits 1.11 - 1.11 1.11 - Total (U.S.$ in millions) $ 68.07 $ (0.02 ) $ 68.05 $ 29.19 $ 38.86 The company recognizes the unrealized losses in fair value in equity as these unrealized losses on short term investments have been considered as temporary.

Goodwill

Goodwill	12 Months Ended
	Dec. 31, 2016
Goodwill	4. Goodwill December 31, December 31, 2016 2015 (in thousands) Opening goodwill $ 588,434 $ 463,324 Current year acquisitions (note 4 (a)) 34,576 133,123 Prior period acquisition (note 4(b)) 7,689 4,418 Foreign exchange movement (14,611 ) (12,431 ) Closing goodwill $ 616,088 $ 588,434 The Company has made a number of strategic acquisitions since inception to enhance its capabilities and experience in certain areas of the clinical development process. Goodwill arising on acquisition represents the excess of the cost of acquired entities over the net amounts assigned to assets acquired and liabilities assumed. Goodwill primarily comprises of the acquired workforce in place which does not qualify for recognition as an asset apart from goodwill. The Company acquired ClinicalRM during the year-ended December 31, 2016 resulting in the recognition of goodwill of $34.6 million (note 4(a)). The Company tests goodwill annually for impairment or whenever events occur which may indicate impairment. The results of the Company's goodwill impairment testing (assessed at September 30, 2016) during the year ended December 31, 2016 provided no evidence of impairment and indicated the existence of sufficient headroom such that a reasonably possible change to the key assumptions used would be unlikely to result in an impairment of the related goodwill. (a) Acquisition of ClincalRM On September 15, 2016, a subsidiary of the Company, ICON US Holdings Inc. acquired Clinical Research Management, Inc. ("ClinicalRM") which resulted in initial net cash outflows of $52.4 million (including certain payments made on behalf of ClinicalRM totaling $9.2 million). ClinicalRM is a full-service CRO specializing in preclinical through Phase IV support of clinical research and clinical trial services for biologics, drugs and devices. The organization helps customers progress their products to market faster with a wide array of research, regulatory and sponsor services within the U.S. and around the globe. ClinicalRM provide full service and functional research solutions to a broad range of US government agencies. Their extensive expertise extends across basic and applied research, infectious diseases, vaccines development, testing and the response to bio-threats. They have worked in collaboration with government and commercial customers to respond to the threat of global viral epidemics. Further consideration of up to $12.0 million is payable if certain performance milestones are achieved in respect of periods up to December 31, 2017. The fair value of the deferred consideration on acquisition has been estimated as $6 million. The acquisition of ClinicalRM has been accounted for as a business combination in accordance with FASB ASC 805 Business Combinations September 15, 2016 (in thousands) Cash $ 3,168 Property, plant and equipment 939 Goodwill* 34,576 Intangible assets** 8,644 Accounts receivable 11,725 Unbilled revenue 2,814 Prepayments and other current assets 1,673 Accounts payable (621 ) Other liabilities (4,515 ) Non-current other liabilities (7 ) Net assets acquired $ 58,396 Cash consideration 52,396 Contingent consideration $ 6,000 Net purchase consideration $ 58,396 *Goodwill represents the acquisition of an established workforce with experience in preclinical through Phase IV support of clinical research and clinical trial services for biologics, drugs and devices. Goodwill related to the US portion of the business acquired is tax deductible. **The Company has made an initial estimate of separate intangible assets (comprised of customer relationships and order book) acquired of $8.6 million. This assessment is under review and will be finalized within 12 months of the date of acquisition. The proforma effect of the ClinicalRM acquisition if completed on January 1, 2015 would have resulted in net revenue, net income and earnings per share for the fiscal years ended December 31, 2016 and December 31, 2015 as follows: Year Ended December 31, 2016 2015 (in thousands) Net revenue $ 1,713,245 $ 1,639,085 Net income $ 266,148 $ 244,167 Basic earnings per share $ 4.82 $ 4.16 Diluted earnings per share $ 4.72 $ 4.05 (b) Acquisition of PMG On December 4, 2015, a subsidiary of the Company, ICON Clinical Research LLC. acquired PMG for cash consideration of $53.7 million. The Company also made certain payments on behalf of PMG totaling $10.1 million. PMG is an integrated network of 48 clinical research sites in North Carolina, South Carolina, Tennessee and Illinois. The site network includes wholly owned facilities and dedicated clinical research sites. PMG conducts clinical trials in all major therapeutic areas and has particular expertise in vaccine, gastroenterology, cardiovascular, neurology and endocrinology studies. It has a proprietary database of clinical trial participants. It also has access to in excess of 2 million active patients via electronic medical records through its partnerships with health care institutions and community physical practices. The acquisition agreement provides for working capital targets to be achieved by PMG. The acquisition of PMG has been accounted for as a business combination in accordance with FASB ASC 805 Business Combinations December 4, 2015 (in thousands) Cash $ 194 Property, plant and equipment 712 Goodwill* 48,728 Customer lists 6,938 Order backlog 2,948 Accounts receivable 11,597 Prepayments and other current assets 1,329 Accounts payable (530 ) Other liabilities (3,456 ) Non-current deferred tax liability (3,106 ) Net assets acquired 65,354 Cash consideration 53,681 Other liabilities assumed 10,060 Working capital adjustment 1,613 Total cash outflows 65,354 *Goodwill represents the acquisition of an established workforce with experience in clinical trial consulting and regulatory support for the development of drugs, medical devices and diagnostics, with a specific focus on strategy to increase efficiency and productivity in product development. In finalizing the goodwill on acquisition of PMG in the twelve month period from acquisition, fair value adjustments were made to deferred tax liabilities ($3.1 million), accounts receivable acquired ($1.4 million), other liabilities ($1.2 million) and the value of the customer list and order backlog assets acquired ($0.4 million). Additional consideration of $1.6 million was provided on completion of the contractual working capital process. The proforma effect of the PMG acquisition if completed on January 1, 2014 would have resulted in net revenue, net income and earnings per share for the fiscal years ended December 31, 2015 and December 31, 2014 as follows: Year Ended December 31, 2015 2014 (in thousands) Net revenue $ 1,601,891 $ 1,527,685 Net income $ 243,004 $ 172,390 Basic earnings per share $ 4.14 $ 2.80 Diluted earnings per share $ 4.03 $ 2.73 (c) Acquisition of MediMedia Pharma Solutions On February 27, 2015, a subsidary of the Company, ICON Holdings Unlimited Company (formerly ICON Holdings), acquired MediMedia Pharma Solutions for cash consideration of $104.8 million (net of working capital adjustments of $3.9 million). In addition to the cash consideration, certain payments were made on behalf of MediMedia Pharma Solutions on completion totaling $11.3 million. Headquartered in Yardley, Pennsylvania, MediMedia Pharma Solutions includes MediMedia Managed Markets and Complete Healthcare Communications. MediMedia Managed Markets is a leading provider of strategic payer-validated market access solutions. Complete Healthcare Communications is one of the leading medical and scientific communication agencies working with medical affairs, commercial and brand development teams within life science companies. The acquisition agreement provides for certain working capital targets to be achieved by MediMedia Pharma Solutions. The acquisition of MediMedia Pharma Solutions has been accounted for as a business combination in accordance with FASB ASC 805 Business Combinations February 27, 2015 (in thousands) Property, plant and equipment $ 1,049 Goodwill* 92,084 Customer lists 22,752 Order backlog 2,521 Accounts receivable 5,240 Unbilled Revenue 4,324 Prepayments and other current assets 621 Accounts payable (749 ) Payments on account (4,186 ) Deferred tax liability (2,171 ) Other liabilities (5,483 ) Net assets acquired $ 116,002 Cash consideration $ 108,717 Other liabilities assumed** 11,283 Gross cash outflows 120,000 Working capital adjustment (3,998 ) Net cash outflows $ 116,002 * Goodwill represents the acquisition of an established workforce with experience in the provision of strategic payer-validated market access solutions while the acquisition of Complete Healthcare Communications comprises an established workforce with significant communication experience working with medical affairs, commercial and brand development teams within the life science industry. Goodwill related to the US portion of the business acquired is tax deductible. ** Payments made at acquisition date of $11.3 million were in respect of certain one-time liabilities at the acquisition date which have subsequently been discharged. The proforma effect of the MediMedia Pharma Solutions acquisition if completed on January 1, 2014 would have resulted in net revenue, net income and earnings per share for the fiscal years ended December 31, 2015 and December 31, 2014 as follows: Year Ended December 31, 2015 2014 (in thousands) Net revenue $ 1,581,816 $ 1,556,936 Net income $ 239,361 $ 179,289 Basic earnings per share $ 4.07 $ 2.92 Diluted earnings per share $ 3.97 $ 2.84 (d) Acquisitions of Aptiv Solutions On May 7, 2014, a subsidiary of the Company, ICON US Holdings Inc., acquired 100% of the common stock of Aptiv Solutions, Inc. ("Aptiv"), a global biopharmaceutical and medical device development services company and leader in adaptive clinical trials for cash consideration of $143.5 million, including certain payments to be made on behalf of the Company on completion totaling $22.4 million. The acquisition agreement provided for working capital targets to be achieved. On March 25, 2015, the Company received $1.9 million in respect of these targets on completion of the working capital review. Aptiv offers full-service clinical trial consulting and regulatory support for drugs, medical devices and diagnostics with a specific focus on strategies to increase product development efficiency and productivity. It is a market leader in the integrated design and execution of adaptive clinical trials for exploratory and late phase development as well as being an industry leader in medical device and diagnostic development in key medical technology segments. The acquisition of Aptiv has been accounted for as a business combination in accordance with FASB ASC 805 Business Combinations May 7, 2014 (in thousands) Property, plant and equipment $ 6,924 Goodwill* 125,627 Customer relationships 21,400 Order backlog 7,900 Cash and cash equivalents 3,484 Accounts receivable 25,091 Unbilled revenue 21,154 Prepayments and other current assets 4,180 Non-current assets 2,911 Accounts payable (9,565 ) Other liabilities (29,782 ) Payments on account (31,094 ) Non-current other liabilities (11,303 ) Loan notes payable** (17,790 ) Net assets acquired $ 119,137 Cash consideration $ 143,500 Working capital adjustment (1,964 ) 141,536 Adjustments to cash consideration** (22,399 ) Net purchase consideration $ 119,137 *Goodwill represents the acquisition of an established workforce with experience in clinical trial consulting and regulatory support for the development of drugs, medical devices and diagnostics, with a specific focus on strategy to increase efficiency and productivity in product development. Goodwill related to the US portion of the business acquired is tax deductible. **Adjustments to cash consideration represent certain one-time liabilities (including loan notes) identified at the acquisition date which have subsequently been paid. The proforma effect of the Aptiv Solutions acquisition if completed on January 1, 2013 would have resulted in net revenue, net income and earnings per share for the fiscal years ended December 31, 2013 and December 31, 2014 as follows: Year Ended December 31, 2014 2013 (in thousands) Net revenue $ 1,543,820 $ 1,451,682 Net income $ 172,508 $ 101,857 Basic earnings per share $ 2.81 $ 1.67 Diluted earnings per share $ 2.73 $ 1.64

Intangible Assets

Intangible Assets	12 Months Ended
	Dec. 31, 2016
Intangible Assets	5. Intangible Assets December 31, December 31, 2016 2015 Cost (in thousands) Customer relationships acquired $ 87,218 $ 90,541 Technology asset acquired 11,169 11,169 Order backlog 16,540 13,592 Trade names acquired 1,357 1,357 Volunteer list acquired 1,325 1,325 Non-compete arrangements 489 489 ClinicalRM intangible asset 8,644 - Foreign exchange movement (6,578 ) (5,092 ) Total cost 120,164 113,381 Accumulated amortization (67,037 ) (49,587 ) Foreign exchange movement 3,483 2,333 Net book value $ 56,610 $ 66,127 On September 15, 2016, a subsidiary of the Company, ICON US Holdings Inc., acquired ClinicalRM, a full-service CRO specializing in preclinical through Phase IV support of clinical research and clinical trial services for biologics, drugs and devices. The organization helps customers progress their products to market faster with a wide array of research, regulatory and sponsor services within the U.S. and around the globe. ClinicalRM provide full service and functional research solutions to a broad range of US government agencies. The value of intangible assets have been provisionally identified of $8.6 million is being amortized over approximately 6 years, the estimated period of benefit. In total, $0.9 million has been amortized in the period since the date of acquisition. On December 4, 2015, a subsidiary of the Company, ICON Clinical Research LLC, acquired PMG, an integrated network of 48 clinical research sites in North Carolina, South Carolina, Tennessee and Illinois. The site network includes wholly owned facilities and dedicated clinical research sites. PMG conducts clinical trials in all major therapeutic areas and has particular expertise in vaccine, gastroenterology, cardiovascular, neurology and endocrinology studies. The value of certain customer relationship and order backlog assets identified of $6.9 million and $3.0 million respectively are being amortized over approximately 7 years and 2 years respectively, the estimated period of benefit. In total, $2.7 million has been amortized in the period since the date of acquisition. On February 27, 2015, a subsidiary of the Company, ICON Holdings Unlimited Company (formerly ICON Holdings), acquired MediMedia Pharma Solutions. Headquartered in Yardley, Pennsylvania, MediMedia Pharma Solutions includes MediMedia Managed Markets and Complete Healthcare Communications. MediMedia Managed Markets is a leading provider of strategic payer-validated market access solutions. Complete Healthcare Communications is one of the leading medical and scientific communication agencies working with medical affairs, commercial and brand development teams within life science companies. The value of certain customer relationships and order backlog identified of $22.8 million and $2.5 million respectively are being amortized over approximately 7 years and 1 year, the estimated period of benefit. $8.5 million has been amortized in the period since the date of acquisition. The order backlog is fully amortized at December 31, 2016. On May 7, 2014, a subsidiary of the Company, ICON US Holdings Inc., acquired Aptiv Solutions, Inc. ("Aptiv"), a global biopharmaceutical and medical device development services company and leader in adaptive clinical trials. Aptiv offers full-service clinical trial consulting and regulatory support for drugs, medical devices and diagnostics with a specific focus on strategy to increase product development efficiency and productivity. The value of certain customer relationships and order backlog identified of $21.4 million and $7.9 million respectively are being amortized over approximately 7 years and 3 years, the estimated period of benefit. In total, $15.2 million has been amortized in the period since the date of acquisition. On February 15, 2013, subsidiaries of the Company, ICON Clinical Research LLC (formerly ICON Clinical Research, Inc.) and ICON Clinical Research (U.K.) Limited, acquired the Clinical Trial Services division of Cross Country Healthcare, Inc. Cross Country Healthcare's Clinical Trial Services division includes US resourcing providers, ClinForce and Assent Consulting, whose services include contract staffing, permanent placement and functional service provision ("FSP"). The value of certain customer relationships and order backlog identified of $3.3 million and $0.6 million respectively are being amortized over approximately 3 years and 1 year, the estimated period of benefit. The full $3.9 million has been amortized in the period since the date of acquisition. On February 28, 2012, a subsidiary of the Company, ICON Clinical Research LLC (formerly ICON Clinical Research, Inc.), acquired PriceSpective, a strategy consulting company. The value of certain customer relationships identified of $10.2 million is being amortized over approximately 10 years, the estimated period of benefit. The value of order backlog and certain non-compete arrangements identified of $0.4 million and $0.4 million respectively are being amortized over approximately 0.8 year and 3 years, the estimated period of benefit. In total, $5.7 million has been amortized in the period since the date of acquisition. On February 15, 2012, a subsidiary of the Company, ICON Clinical Research Limited, acquired BeijingWits Medical, a Chinese CRO. The value of certain customer relationships and order backlog identified of $1.8 million and $0.4 million respectively are being amortized over approximately 10 years and 4 years, the estimated period of benefit. The value of certain non-compete arrangements identified of $0.01 million are being amortized over approximately 5 years, the estimated period of benefit. In total, $1.3 million has been amortized in the period since the date of acquisition. On July 14, 2011, a subsidiary of the Company, ICON Clinical Research Limited, acquired Firecrest Clinical Limited, a provider of technology solutions that boost investigator site performance and study management. The value of certain technology assets and customer relationships identified of $11.2 million and $5.2 million respectively are being amortized over approximately 7.5 years, the estimated period of benefit. The value of the Firecrest trade name and order backlog identified of $1.4 million and $1.2 million respectively are being amortized over approximately 4.5 years and 1.2 years, the estimated period of benefit. In total, $12.8 million has been amortized in the period since the date of acquisition. On January 14, 2011, a subsidiary of the Company, ICON Clinical Research (U.K.) Limited, acquired Oxford Outcomes Limited, an international health outcomes consultancy business. The value of certain customer relationships and order backlog identified of $6.6 million and $0.6 million respectively are being amortized over approximately 6.5 years and 2 years, the estimated period of benefit. In total, $6.7 million has been amortized in the period since the date of acquisition. On November 14, 2008, subsidiaries of the Company, ICON Holdings Clinical Research International Limited and ICON Clinical Research LLC (formerly ICON Clinical Research, Inc.), acquired Prevalere Life Sciences, a US provider of bioanalytical and immunoassay laboratory services. On February 11, 2008, a subsidiary of the Company, ICON Clinical Research LLC (formerly ICON Clinical Research, Inc.), acquired Healthcare Discoveries, a US provider of Phase I clinical trial services. The value of certain client relationships identified of $1.6 million is being amortized over periods ranging from approximately 2 to 9 years, the estimated periods of benefit. The value of certain volunteer lists identified of $1.3 million is being amortized over approximately 6 years, the estimated period of benefit. The full $2.9 million has been amortized in the period since the date of acquisition. Future intangible asset amortization expense for the years ended December 31, 2017 to December 31, 2021 is as follows: Year ended December 31, (in thousands) 2017 $ 15,449 2018 11,815 2019 9,921 2020 9,634 2021 7,597 $ 54,416

Property, Plant and Equipment,

Property, Plant and Equipment, net	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment, net	6. Property, Plant and Equipment, net December 31, December 31, 2016 2015 (in thousands) Cost Land $ 3,464 $ 3,464 Building 77,950 80,861 Computer equipment and software 315,984 282,909 Office furniture and fixtures 70,218 65,152 Laboratory equipment 31,487 31,098 Leasehold improvements 20,933 20,647 Motor vehicles 43 47 520,079 484,178 Less accumulated depreciation and asset write offs (371,112 ) (333,960 ) Property, plant and equipment (net) $ 148,967 $ 150,218

Other Liabilities

Other Liabilities	12 Months Ended
	Dec. 31, 2016
Other Liabilities	7. Other Liabilities December 31, December 31, 2016 2015 (in thousands) Personnel related liabilities $ 135,349 $ 159,339 Facility related liabilities 14,182 22,517 General overhead liabilities 31,126 29,257 Other liabilities 7,584 18,607 Short term government grants (note 11) 54 43 Restructuring and other items (note 14) 2,432 2,116 $ 190,727 $ 231,879

Other Non-Current Liabilities

Other Non-Current Liabilities	12 Months Ended
	Dec. 31, 2016
Other Non-Current Liabilities	8. Other Non-Current Liabilities December 31, December 31, 2016 2015 (in thousands) Defined benefit pension obligations, net (note 9) 8,952 7,189 Other non-current liabilities* 14,800 5,035 $ 23,752 $ 12,224 *An amount of $6.0 million is included within other non-current liabilities in respect of contingent consideration for the acquisition of ClinicalRM. See note 4 (a).

Employee Benefits

Employee Benefits	12 Months Ended
	Dec. 31, 2016
Employee Benefits	9. Employee Benefits Certain Company employees are eligible to participate in a defined contribution plan (the "Plan"). Participants in the Plan may elect to defer a portion of their pre-tax earnings into a pension plan, which is run by an independent party. The Company matches participant's contributions typically at 6% of the participant's annual compensation. Contributions to the plan are recorded as an expense in the Consolidated Statement of Operations. Contributions for the years ended December 31, 2014, December 31, 2015 and December 31, 2016 were $22,370,000, $20,439,000 and $20,952,000 respectively. The Company's United States operations maintain a retirement plan (the "U.S. Plan") that qualifies as a deferred salary arrangement under Section 401(k) of the Internal Revenue Code. Participants in the U.S. Plan may elect to defer a portion of their pre-tax earnings, up to the Internal Revenue Service annual contribution limit. The Company matches 50% of each participant's contributions; each participant can contribute up to 6% of their annual compensation. Contributions to this U.S. Plan are recorded, in the year contributed, as an expense in the Consolidated Statement of Operations. Contributions for the years ended December 31, 2014, December 31, 2015 and December 31, 2016 were $10,514,000, $12,802,000 and $15,223,000 respectively. One of the Company's subsidiaries, ICON Development Solutions Limited, operates a defined benefit pension plan in the United Kingdom for its employees. The plan is managed externally and the related pension costs and liabilities are assessed in accordance with the advice of a professionally qualified actuary. Plan assets at December 31, 2016, December 31, 2015 and December 31, 2014, consist of units held in independently administered funds. The pension costs of this plan are presented in the following tables in accordance with the requirements of ASC 715-60, Defined Benefit Plans – Other Postretirement Change in benefit obligation December 31, 2016 December 31, 2015 (in thousands) Benefit obligation at beginning of year $ 27,369 $ 32,875 Service cost 75 78 Interest cost 1,017 1,140 Plan participants' contributions 22 26 Expenses 8 - Benefits paid (104 ) (1,111 ) Actuarial loss/(gain) 10,057 (3,992 ) Foreign currency exchange rate changes (5,538 ) (1,647 ) Benefit obligation at end of year $ 32,906 $ 27,369 Change in plan assets December 31, 2016 December 31, 2015 (in thousands) Fair value of plan assets at beginning of year $ 23,367 $ 25,409 Actual return on plan assets 5,861 277 Employer contributions 108 114 Plan participants' contributions 22 26 Benefits paid (104 ) (1,111 ) Foreign currency exchange rate changes (4,378 ) (1,348 ) Fair value of plan assets at end of year $ 24,876 $ 23,367 The fair values of the assets above do not include any of the Company's own financial instruments, property occupied by, or other assets used by, the Company. Funded status December 31, 2016 December 31, 2015 (in thousands) Projected benefit obligation $ (32,906 ) $ (27,369 ) Fair value of plan assets 24,876 23,367 Funded status $ (8,030 ) $ (4,002 ) Non-current other liabilities (note 8) $ (8,030 ) $ (4,002 ) The following amounts were recorded in the consolidated statement of operations as components of the net periodic benefit cost: December 31, 2016 December 31, 2015 December 31, 2014 (in thousands) Service cost $ 75 $ 78 $ 91 Interest cost 1,017 1,140 1,235 Expected return on plan assets (646 ) (661 ) (1,299 ) Amortization of net loss - 224 20 Expenses 8 - 359 Net periodic benefit cost $ 454 $ 781 $ 406 The following assumptions were used at the commencement of the year in determining the net periodic pension benefit cost for the years ended December 31, 2014, December 31, 2015 and December 31, 2016: December 31, December 31, December 31, 2016 2015 2014 Discount rate 4.0 % 3.6 % 4.7 % Rate of compensation increase 3.7 % 3.6 % 4.0 % Expected rate of return on plan assets 3.0 % 2.7 % 6.1 % Accumulated other comprehensive income December 31, 2016 December 31, 2015 December 31, 2014 (in thousands) Actuarial loss/(gain) - benefit obligation $ 10,057 $ (3,992 ) $ 8,270 Actuarial (gain)/loss – plan assets (5,215 ) 384 (4,125 ) Actuarial gain recognized in net periodic benefit cost - (224 ) (20 ) Total $ 4,842 $ (3,832 ) $ 4,125 The estimated net loss and prior service cost for the defined benefit pension plan that will be amortized from accumulated other comprehensive income into net periodic benefit cost over the next year are $0.2 million and $Nil respectively. Amounts recognized in accumulated other comprehensive income that have not yet been recognized as components of net periodic benefit cost are as follows: December 31, 2016 December 31, 2015 December 31, 2014 (in thousands) Net actuarial loss $ 7,123 $ 2,281 $ 6,113 Total $ 7,123 $ 2,281 $ 6,113 Benefit Obligation The following assumptions were used in determining the benefit obligation at December 31, 2016 and December 31, 2015: December 31, December 31, 2016 2015 Discount rate 2.7 % 4.0 % Rate of compensation increase 3.9 % 3.7 % The discount rate is determined by reference to UK long dated government and corporate bond yields at the balance sheet date. This is represented by the iboxx corporate bond over 15 year index plus 10 basis points. Plan Assets The assets of the scheme are invested with Legal and General and held in a combination of the Active Corporate Bond over 10 Year fund, Gilt and Index Linked Gilt funds. The overall investment strategy is that approximately 75% of investments are in government bonds (both fixed interest and index linked) and approximately 25% of investments are held in corporate bonds. There is no self-investment in employer related assets. The expected long-term rate of return on assets at December 31, 2016 of 2.1% was calculated as the value of the fund after application of a market value reduction factor. The expected long term rates of return on different asset classes are as follows: Asset Category Expected long-term return per annum Corporate Bonds 2.7 % Gilts 1.9 % The long-term expected return on corporate bonds and gilts (fixed interest and index linked) is determined by reference to bond yields and gilt yields at the balance sheet date. The underlying asset split of the fund is shown below. Asset Category December 31, 2016 December 31, 2015 Corporate Bonds 25 % 26 % Gilts 75 % 74 % 100 % 100 % Applying the above expected long term rates of return to the asset distribution at December 31, 2016, gives rise to an expected overall rate of return of scheme assets of approximately 2.1% per annum. Plan Asset Fair Value Measurements Quoted Prices in Active Markets for Identical Assets Level 1 (in thousands) December 31, 2016 December 31, 2015 Cash $ 16 $ 3 Fixed Income Securities Legal and General Active Corporate Bond – Over 10 Year 6,095 6,256 Legal and General Gilt Funds 6,725 6,528 Legal and General Index Linked Gilt Funds 12,040 10,580 $ 24,876 $ 23,367 Cash Flows The Company expects to contribute $0.1 million to the pension fund in the year ending December 31, 2017. The following annual benefit payments, which reflect expected future service as appropriate, are expected to be paid. (in thousands) 2017 64 2018 65 2019 68 2020 70 2021 73 Years 2022 - 2026 $ 362 The expected cash flows are estimated figures based on the members expected to retire over the next 10 years assuming no early retirements plus an additional amount based on recent average withdrawal experience. At the present time it is not clear whether annuities will be purchased when members reach retirement or whether pensions will be paid each month out of scheme assets. The cash flows above have been estimated on the assumption that pensions will be paid monthly out of scheme assets. If annuities are purchased, then the expected benefit payments will be significantly different from those shown above. On May 7, 2014 the Company acquired 100% of the common stock of Aptiv Solutions ("Aptiv"). The acquisition of Aptiv was accounted for as a business combination in accordance with FASB ASC 805 Business Combinations Defined Benefit Plans – Other Postretirement Change in benefit obligation December 31, 2016 December 31, 2015 (in thousands) Benefit obligation at beginning of year 8,537 8,884 Service cost 352 618 Interest cost 82 159 Plan participants' contributions 150 - Settlement (909 ) - Prior service cost (88 ) - Transferred balances/(benefits paid) 53 (1,146 ) Actuarial (gain)/ loss (1,157 ) 81 Foreign currency exchange rate changes (92 ) (59 ) Benefit obligation at end of year 6,928 8,537 Change in plan assets Fair value of plan assets at beginning of year 5,350 7,061 Expected return on plan assets 48 93 Actual return on plan assets 1,233 (1,075 ) Scheme contributions 195 194 Plan participants' contributions 150 216 Transferred balances/(benefits paid) 53 (1,146 ) Settlement (909 ) - Foreign currency exchange rate changes (114 ) 7 Fair value of plan assets at end of year 6,006 5,350 The fair values of the assets above do not include any of the Company's own financial instruments, property occupied by, or other assets used by, the Company. Funded status December 31, 2016 December 31, 2015 (in thousands) Projected benefit obligation $ (6,928 ) $ (8,537 ) Fair value of plan assets 6,006 5,350 Funded status (922 ) (3,187 ) Non-current other liabilities (note 8) $ (922 ) $ (3,187 ) December 31, 2016 December 31, 2015 (in thousands) Service cost $ 352 $ 402 Interest cost 82 159 Expected return on plan assets (48 ) (119 ) Amortization of net loss 22 - Amortization of prior service credit (8 ) - Settlement (136 ) - Curtailment loss - 18 Net periodic benefit cost $ 264 $ 460 The following assumptions were used at the commencement of the year in determining the net periodic pension benefit cost for the years ended December 31, 2016 and December 31, 2015: December 31, December 31, 2016 2015 Discount rate 0.95 % 1.35 % Rate of compensation increase 2.0 % 2.0 % Expected rate of return on plan assets 0.95 % 1.35 % Accumulated other comprehensive income December 31, 2016 December 31, 2015 Actuarial (gain)/loss - benefit obligation $ (1,157 ) $ 81 Actuarial (gain)/loss – plan assets (1,233 ) 1,075 Prior service credit/(cost) recognized in net periodic benefit cost 136 (17 ) Actuarial loss recognized in net periodic benefit cost (22 ) - Amortization of net prior service credit 8 - Net prior service credit occurring during the year (89 ) - Total $ (2,357 ) $ 1,139 The estimated net loss and prior service cost for the defined benefit pension plan that will be amortized from accumulated other comprehensive income into net periodic benefit cost over the next year are $41,000 and $8,000 respectively. Amounts recognized in accumulated other comprehensive income that have not yet been recognized as components of net periodic benefit cost are as follows: December 31, 2016 December 31, 2015 (in thousands) Net actuarial (gain)/loss $ (1,218 ) $ 1,139 Total $ (1,218 ) $ 1,139 Benefit Obligation The following assumptions were used in determining the benefit obligation at December 31, 2016 and December 31, 2015: December 31, December 31, 2016 2015 Discount rate 0.75 % 0.95 % Rate of compensation increase 2.0 % 2.0 % The discount rate is determined by reference to Swiss corporate bond yields at the balance sheet date. Plan Assets The assets of the scheme are invested in an insured plan with Swiss Life and held in a combination of debt securities, equity securities and in real estate. There is no self-investment in employer related assets. Cash Flows The Company expects to contribute $0.2 million to its pension fund in the year ending December 31, 2017. The following annual benefit payments, which reflect expected future service as appropriate, are expected to be paid. (in thousands) 2017 305 2018 306 2019 685 2020 251 2021 249 Years 2022 - 2026 $ 1,676 The expected cash flows are estimated figures based on the members expected to retire over the next 10 years assuming no early retirements plus an additional amount based on recent average withdrawal experience. At the present time it is not clear whether annuities will be purchased when members reach retirement or whether pensions will be paid each month out of scheme assets. The cash flows above have been estimated on the assumption that pensions will be paid monthly out of scheme assets. If annuities are purchased, then the expected benefit payments will be significantly different from those shown above.

Equity Incentive Schemes and St

Equity Incentive Schemes and Stock Compensation Charges	12 Months Ended
	Dec. 31, 2016
Equity Incentive Schemes and Stock Compensation Charges	10. Equity Incentive Schemes and Stock Compensation Charges Share Options On July 21, 2008 the Company adopted the Employee Share Option Plan 2008 (the "2008 Employee Plan") pursuant to which the Compensation and Organization Committee of the Company's Board of Directors may grant options to any employee, or any Director holding a salaried office or employment with the Company or a Subsidiary for the purchase of ordinary shares. On the same date, the Company also adopted the Consultants Share Option Plan 2008 (the "2008 Consultants Plan"), pursuant to which the Compensation and Organization Committee of the Company's Board of Directors may grant options to any consultant, adviser or non-executive Director retained by the Company or any Subsidiary for the purchase of ordinary shares. On February 14, 2017 both the 2008 Employee Plan and the 2008 Consultants Plan (together the "2008 Option Plans") were amended and restated in order to increase the number of options that can be issued under the 2008 Consultants Plan from 400,000 to 1 million and to extend the date for options to be granted under the 2008 Option Plans. An aggregate of 6.0 million ordinary shares have been reserved under the 2008 Employee Plan, as reduced by any shares issued or to be issued pursuant to options granted under the 2008 Consultants Plan, under which a limit of 1 million shares applies. Further, the maximum number of ordinary shares with respect to which options may be granted under the 2008 Employee Option Plan, during any calendar year to any employee shall be 400,000 ordinary shares. There is no individual limit under the 2008 Consultants Plan. No options may be granted under the 2008 Option Plans after February 14, 2027. Each option granted under the 2008 Option Plans will be an employee stock option, or NSO, as described in Section 422 or 423 of the Internal Revenue Code. Each grant of an option under the 2008 Options Plans will be evidenced by a Stock Option Agreement between the optionee and the Company. The exercise price will be specified in each Stock Option Agreement, however option prices will not be less than 100% of the fair market value of an ordinary share on the date the option is granted. On January 17, 2003 the Company adopted the Share Option Plan 2003 (the "2003 Share Option Plan") pursuant to which the Compensation and Organization Committee of the Board could grant options to officers and other employees of the Company or its subsidiaries for the purchase of ordinary shares. An aggregate of 6.0 million ordinary shares were reserved under the 2003 Share Option Plan; and in no event could the number of ordinary shares issued pursuant to options awarded under this plan exceed 10% of the outstanding shares, as defined in the 2003 Share Option Plan, at the time of the grant, unless the Board expressly determined otherwise. Further, the maximum number of ordinary shares with respect to which options could be granted under the 2003 Share Option Plan during any calendar year to any employee was 400,000 ordinary shares. The 2003 Share Option Plan expired on January 17, 2013. No new options may be granted under this plan. Share option awards are granted with an exercise price equal to the market price of the Company's shares at date of grant. Share options typically vest over a period of five years from date of grant and expire eight years from date of grant. The maximum contractual term of options outstanding at December 31, 2016 is eight years. The following table summarizes the transactions for the Company's share option plans for the years ended December 31, 2016, December 31, 2015 and December 31, 2014: Options Granted Under Plans Number of Shares Weighted Average Exercise Price Weighted Average Grant Date Fair Value Outstanding at December 31, 2013 2,973,788 2,973,788 $ 24.20 $ 9.57 Granted 366,985 366,985 $ 45.82 $ 14.09 Exercised (926,407 ) (926,407 ) $ 24.02 $ 9.45 Cancelled (186,666 ) (186,666 ) $ 22.17 $ 9.01 Outstanding at December 31, 2014 2,227,700 2,227,700 $ 28.00 $ 10.40 Granted 259,059 259,059 $ 68.25 $ 19.75 Exercised (773,753 ) (773,753 ) $ 27.13 $ 10.31 Cancelled (86,424 ) (86,424 ) $ 27.32 $ 10.31 Outstanding at December 31, 2015 1,626,582 1,626,582 $ 34.87 $ 11.94 Granted 256,191 256,191 $ 69.61 $ 20.10 Exercised (393,240 ) (393,240 ) $ 25.79 $ 9.84 Cancelled (23,089 ) (23,089 ) $ 29.74 $ 11.19 Outstanding at December 31, 2016 1,466,444 1,466,444 $ 43.45 $ 13.94 Vested and exercisable at December 31, 2016 651,574 651,574 $ 29.80 $ 10.69 The weighted average remaining contractual life of options outstanding and options exercisable at December 31, 2016, was 4.67 years and 3.30 years respectively (2015: 4.76 years and 3.39 years respectively). 333,433 options are expected to vest during the year ended December 31, 2017 (336,993 options were expected to vest during the year ended December 31, 2016). The intrinsic value of options exercised during the year ended December 31, 2016 amounted to $19.6 million. The intrinsic value of options outstanding and options exercisable at December 31, 2016 amounted to $46.6 million and $29.6 million respectively. Intrinsic value is calculated based on the market value versus strike price of the Company's shares at the date of exercise. Non-vested shares outstanding as at December 31, 2016 are as follows: Options Outstanding Number of Shares Weighted Average Exercise Price Weighted Average Fair Value Non-vested outstanding at December 31, 2015 968,853 $ 42.14 $ 13.69 Granted 256,191 69.61 20.10 Vested (391,918 ) 35.17 12.04 Forfeited (18,256 ) 31.48 11.62 Non-vested outstanding at December 31, 2016 814,870 $ 54.37 $ 16.55 Outstanding and exercisable share options: The following table summarizes information concerning outstanding and exercisable share options as of December 31, 2016: Options Outstanding Options Exercisable Range Exercise Price Number of Shares Weighted Average Remaining Contractual Life Weighted Average Exercise Price Number of Shares Weighted Average Exercise Price $ 15.84 50,000 0.32 $ 15.84 50,000 $ 15.84 $ 16.80 60,000 2.83 $ 16.80 60,000 $ 16.80 $ 17.17 6,000 2.85 $ 17.17 6,000 $ 17.17 $ 20.28 107,588 2.16 $ 20.28 107,588 $ 20.28 $ 20.59 33,000 3.14 $ 20.59 7,200 $ 20.59 $ 22.26 2,160 0.15 $ 22.26 2,160 $ 22.26 $ 22.30 173,642 3.32 $ 22.30 112,061 $ 22.30 $ 23.66 3,520 3.57 $ 23.66 1,910 $ 23.66 $ 24.46 60,816 1.17 $ 24.46 60,816 $ 24.46 $ 26.20 450 1.38 $ 26.20 450 $ 26.20 $ 26.71 4,450 3.69 $ 26.71 3,560 $ 26.71 $ 29.45 3,000 1.32 $ 29.45 3,000 $ 29.45 $ 32.37 165,865 4.33 $ 32.37 95,457 $ 32.37 $ 36.22 20,178 4.46 $ 36.22 8,443 $ 36.22 $ 37.90 5,720 4.93 $ 37.90 1,600 $ 37.90 $ 40.83 81,658 5.39 $ 40.83 24,646 $ 40.83 $ 47.03 63,813 5.17 $ 47.03 15,693 $ 47.03 $ 48.67 118,493 5.21 $ 48.67 22,992 $ 48.67 $ 51.35 4,030 5.60 $ 51.35 1,612 $ 51.35 $ 65.60 93,534 7.38 $ 65.60 10,557 $ 65.60 $ 66.47 11,931 6.39 $ 66.47 1,417 $ 66.47 $ 66.97 3,118 6.45 $ 66.97 623 $ 66.97 $ 68.39 231,687 6.18 $ 68.39 53,789 $ 68.39 $ 71.95 161,791 7.17 $ 71.95 - $ 71.95 $ 15.84 - $71.95 1,466,444 4.67 $ 43.45 651,574 $ 29.80 Options outstanding include both vested and unvested options as at December 31, 2016. Options exercisable represent options which have vested at December 31, 2016. From the date of grant, substantially all options vest over a five year period at 20% per annum. Fair value of Stock Options Assumptions The weighted average fair value of options granted during the years ended December 31, 2016, December 31, 2015 and December 31, 2014 was calculated using the Black-Scholes option pricing model. The weighted average fair values and assumptions were as follows: Year Ended December 31, December 31, December 31, 2016 2015 2014 Weighted average fair value $ 20.10 $ 19.75 $ 14.09 Assumptions: Expected volatility 30 % 30 % 32 % Dividend yield 0 % 0 % 0 % Risk-free interest rate 1.39 % 1.58 % 1.57 % Expected life 5.0 years 5.0 years 5.0 years Expected volatility is based on the historical volatility of our common stock over a period equal to the expected term of the options; the expected life represents the weighted average period of time that options granted are expected to be outstanding given consideration to vesting schedules and our historical experience of past vesting and termination patterns. The risk-free rate is based on the U.S. government zero-coupon bonds yield curve in effect at time of the grant for periods corresponding with the expected life of the option. Restricted Share Units and Performance Share Units On July 21, 2008 the Company adopted the 2008 Employees Restricted Share Unit Plan (the "2008 RSU Plan") pursuant to which the Compensation and Organization Committee of the Company's Board of Directors may select any employee, or any Director holding a salaried office or employment with the Company, or a Subsidiary to receive an award under the plan. An aggregate of 1.0 million ordinary shares have been reserved for issuance under the 2008 RSU Plan. On April 23, 2013 the Company adopted the 2013 Employees Restricted Share Unit and Performance Share Unit Plan (the "2013 RSU Plan") pursuant to which the Compensation and Organization Committee of the Company's Board of Directors may select any employee, or any Director holding a salaried office or employment with the Company, or a Subsidiary to receive an award under the plan. On May 11, 2015 the 2013 RSU Plan was amended and restated in order to increase the number of shares that can be issued under the RSU Plan by 2.5 million shares. Accordingly, an aggregate of 4.1 million ordinary shares have been reserved for issuance under the 2013 RSU Plan. The shares are awarded at par value and vest over a service period. Awards under the 2013 RSU Plan may be settled in cash or shares at the option of the Company. The Company has awarded RSUs and PSUs to certain key individuals of the Group. The following table summarizes RSU and PSU activity for the year ended December 31, 2016: PSU Outstanding Number of Shares PSU Weighted Average Fair Value PSU Weighted Average Remaining Contractual Life RSU Outstanding Number of Shares RSU Weighted Average Fair Value RSU Weighted Average Remaining Contractual Life Outstanding at December 31, 2015 901,773 $ 48.33 1.22 1,067,613 $ 48.30 1.48 Granted 247,992 $ 71.58 391,196 $ 67.45 Shares vested (311,492 ) $ 33.09 (300,019 ) $ 36.13 Forfeited (7,750 ) $ 56.58 (133,306 ) $ 52.36 Outstanding at December 31, 2016 830,523 $ 60.73 1.11 1,025,484 $ 58.64 1.4 0 The fair value of RSUs vested for the year ended December 31, 2016 totaled $10.8 million (2015: $7.0 million). The fair value of PSUs vested for the year ended December 31, 2016 totaled $10.3 million (2015: $0.3 million). The PSUs vest based on service and specified EPS targets over the period 2013 – 2016, 2014 – 2017, 2015 – 2018 and 2016 - 2019. Since 2013, 421,079 PSUs (net of forfeitures) have been granted. Depending on the actual amount of EPS from 2013 to 2019, up to an additional 409,444 PSUs may also be granted. Non-cash stock compensation expense Income from operations for the year ended December 31, 2016 is stated after charging $40.3 million in respect of non-cash stock compensation expense. Non-cash stock compensation expense has been allocated as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Direct costs $ 21,903 $ 18,358 $ 12,531 Selling, general and administrative $ 18,440 $ 14,959 $ 10,211 Total compensation costs $ 40,343 $ 33,317 $ 22,742 Total non-cash stock compensation expense not yet recognized at December 31, 2016 amounted to $64.9 million. The weighted average period over which this is expected to be recognized is 2.07 years. Total tax benefit recognized in additional paid in capital related to the non-cash compensation expense amounted to $4.3 million for the year ended 31 December 2016 (2015: $1.9 million, 2014: $2.4 million). The income tax expense for the year ended December 31, 2016 reflects a net income tax benefit of $3.5 million in connection with stock compensation and the cash tax benefit realized in connection with stock options exercised during 2016 was $3.4 million. The income tax expense for the year ended 31 December 2015 reflects a net income tax benefit of $1.5 million in connection with stock compensation and the cash tax benefit realized in connection with stock options exercised during 2015 was $5.6 million.

Government Grants

Government Grants	12 Months Ended
	Dec. 31, 2016
Government Grants	11. Government Grants December 31, December 31, 2016 2015 (in thousands) Received $ 3,539 $ 3,539 Less accumulated amortization (2,701 ) (2,657 ) Foreign exchange translation adjustment 103 120 Total government grants 941 1,002 Less current portion (54 ) (43 ) Non-current government grants $ 887 $ 959 Capital grants received may be refundable in full if certain events occur. Such events, as set out in the related grant agreements, include sale of the related asset, liquidation of the Company or failure to comply with other conditions of the grant agreements. No loss contingency has been recognized as the likelihood of such events arising has been assessed as remote. Government grants amortized to the profit and loss account amounted to $44,000 for the year ended December 31, 2016. A net charge of $53,000 was recorded in respect of government grants during the year ended December 31, 2015. As at December 31, 2016 the Company had $0.6 million in restricted retained earnings, pursuant to the terms of grant agreements.

Share Capital

Share Capital	12 Months Ended
	Dec. 31, 2016
Share Capital	12. Share Capital Holders of ordinary shares will be entitled to receive such dividends as may be recommended by the Board of Directors of the Company and approved by the shareholders and/or such interim dividends as the Board of Directors of the Company may decide. On liquidation or a winding up of the Company, the par value of the ordinary shares will be repaid out of the assets available for distribution among the holders of the ordinary shares of the Company. Holders of ordinary shares have no conversion or redemption rights. On a show of hands, every holder of an ordinary share present in person or proxy at a general meeting of shareholders shall have one vote, for each ordinary share held with no individual having more than one vote. During the year ended December 31, 2016, 393,240 options were exercised by employees at an average exercise price of $25.79 per share for total proceeds of $10.1 million. During the year ended December 31, 2016, 296,386 ordinary shares were issued in respect of certain RSUs and 311,492 ordinary shares were issued in respect of PSUs previously awarded by the Company. During the year ended December 31, 2015, 773,753 options were exercised by employees at an average exercise price of $27.13 per share for total proceeds of $21.0 million. During the year ended December 31, 2015, 268,870 ordinary shares were issued in respect of certain RSUs and 7,990 ordinary shares were issued in respect of PSUs previously awarded by the Company. During the year ended December 31, 2014, 926,407 options were exercised by employees at an average exercise price of $24.02 per share for total proceeds of $22.3 million. During the year ended December 31, 2014, 233,726 ordinary shares were issued in respect of certain RSUs previously awarded by the Company. (a) Share Repurchase Program On October 3, 2016 the Company commenced a previously announced share buyback program of up to $400 million. The Company can acquire up to 10% of its outstanding ordinary shares (by way of redemption), in accordance with Irish law, the United States securities laws and the Company's constitutional documents through open market share acquisitions. At December 31, 2016 a total of 1,429,187 ordinary shares were redeemed by the Company under this buyback program for a total consideration of $110.0 million. All ordinary shares that were redeemed under the buyback program were canceled in accordance with the Constitution of the Company and the nominal value of these shares transferred to a capital redemption reserve fund as required under Irish Company Law. On May 1, 2015 the Company commenced a buyback program of up to $60 million under which the Company could acquire its outstanding ordinary shares (by way of redemption), in accordance with Irish law, the United States securities laws and the Company's constitutional documents through open market share acquisitions. A total of 882,419 ordinary shares were redeemed by the Company under this buyback program for a total consideration of $57.9 million. All ordinary shares that were redeemed under the buyback program were canceled in accordance with the Constitution of the Company and the nominal value of these shares transferred to a capital redemption reserve fund as required under Irish Company Law. On July 31, 2015 the Company commenced a further buyback program of up to $400 million under which the Company could acquire its outstanding ordinary shares (by way of redemption), in accordance with Irish law, the United States securities laws and the Company's constitutional documents through open market share acquisitions. A total of 5,316,062 ordinary shares were redeemed by the Company under this buyback program for a total consideration of $400 million. All ordinary shares that were redeemed under the buyback program were canceled in accordance with the Constitution of the Company and the nominal value of these shares transferred to a capital redemption reserve fund as required under Irish Company Law. The share buyback program was completed in December 2015, with a total of 6,198,481 ordinary shares redeemed during the year ended December 31, 2015 for total consideration of $457.9 million. During the year ended December 31, 2014 2,640,610 ordinary shares were repurchased by the Company for a total consideration of $140.0 million. All ordinary shares repurchased by the Company were canceled and the nominal value of these shares transferred to a capital redemption reserve fund as required under Irish Company Law. Under the repurchase program, a broker purchased the Company's shares from time to time on the open market or in privately negotiated transactions in accordance with agreed terms and limitations. The program was designed to allow share repurchases during periods when the Company would ordinarily not be permitted to do so because it may be in possession of material non-public or price-sensitive information or due to applicable insider trading laws or self-imposed trading blackout periods. The Company's instructions to the broker were irrevocable and the trading decisions in respect of the repurchase program were made independently of and uninfluenced by the Company. The Company confirms that on entering the share repurchase plans it had no material non-public, price-sensitive or inside information regarding the Company or its securities. Furthermore, the Company will not enter into additional plans whilst in possession of such information. The timing and actual number of shares acquired by way of the redemption will be dependent on market conditions, legal and regulatory requirements and the other terms and limitations contained in the program. In addition, acquisitions under the program may be suspended or discontinued in certain circumstances in accordance with the agreed terms. Therefore, there can be no assurance as to the timing or number of shares that may be acquired under the program.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2016
Income Taxes	13. Income Taxes The Company's United States and Irish based subsidiaries file tax returns in the United States and Ireland respectively. Other foreign subsidiaries are taxed separately under the laws of their respective countries. The components of income before provision for income taxes are as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Ireland $ 201,221 $ 184,643 $ 143,889 United States 11,466 15,436 6,966 Other 87,485 78,771 51,861 Income before provision for income taxes $ 300,172 $ 278,850 $ 202,716 The components of provision for income taxes are as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Provision for income taxes: Current tax expense: Ireland $ 22,931 $ 21,769 $ 19,562 United States 7,768 684 7,891 Other 5,749 13,701 10,695 Total current tax expense 36,448 36,154 38,148 Deferred tax expense/(benefit): Ireland 1,284 26 (1,178 ) United States 613 2,896 (3,031 ) Other (352 ) 235 (3,691 ) Total deferred tax expense/(benefit) 1,545 3,157 (7,900 ) Provision for income taxes 37,993 39,311 30,248 Impact on shareholders equity and other comprehensive income of the tax consequence of : Excess tax benefit on stock compensation (4,332 ) (1,905 ) (2,404 ) Currency impact on long term funding (396 ) 3,574 178 Total $ 33,265 $ 40,980 $ 28,022 Ireland's statutory income tax rate is 12.5%. The Company's consolidated reported provision for income taxes differed from the amount that would result from applying the Irish statutory rate as set forth below; Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Taxes at Irish statutory rate of 12.5% (2015:12.5%; 2014:12.5%) $ 37,522 $ 34,856 $ 25,340 Foreign and other income taxed at higher rates 4,642 4,614 3,152 Research & development tax incentives (907 ) (695 ) (1,810 ) Movement in valuation allowance 1,208 (4,133 ) (1,965 ) Effects of change in tax rates 576 (16 ) 543 Increase/(decrease) in unrecognized tax benefits (1,521 ) 5,085 2,869 Effects of permanent items (4,259 ) (463 ) 2,048 Other 732 63 71 Provision for income taxes $ 37,993 $ 39,311 $ 30,248 The tax effects of temporary differences that give rise to significant portions of deferred tax assets and deferred tax liabilities are presented below: December 31, December 31, 2016 2015 (in thousands) Deferred tax liabilities: Property, plant and equipment $ 979 $ 1,239 Goodwill 26,617 22,170 Other intangible assets 6,700 5,865 Other 1,441 1,293 Total deferred tax liabilities recognized 35,737 30,567 Deferred tax assets: Operating loss and tax credits carryforwards 22,705 22,186 Property, plant and equipment 3,121 2,487 Accrued expenses and payments on account 28,904 29,473 Stock compensation 13,062 12,959 Deferred compensation expense 3,327 2,174 Other 15 566 Total deferred tax assets 71,134 69,845 Valuation allowance for deferred tax assets (20,337 ) (17,184 ) Deferred tax assets recognized 50,797 52,661 Overall net deferred tax asset $ 15,060 $ 22,094 In 2015, the Company early adopted the provisions of ASU 2015-17 which requires entities with a classified balance sheet to present all deferred tax assets and liabilities as noncurrent on the basis that it is a more useful presentation of the Company's position. The prior period amounts were not retrospectively adjusted. At December 31, 2016 Ireland subsidiaries had additional tax credit carryforwards for income tax purposes that may be carried forward indefinitely, available for offset against future tax liabilities, if any, of $3.3 million (2015: $2.9 million). At December 31, 2016 other non U.S. subsidiaries had operating loss carryforwards for income tax purposes that may be carried forward indefinitely, available to offset against future taxable income, if any, of approximately $70.1 million (2015: $68.6 million). In addition at December 31, 2016 other non U.S. subsidiaries had tax credit carryforwards for income tax purposes that may be carried forward indefinitely, available to offset against future tax liabilities, if any, of $3.9 million (2015: $3.0 million). At December 31, 2016 Other non U.S. subsidiaries also had additional operating loss carry forwards of $3.5 million which are due to expire between 2017 and 2023. At December 31, 2016 U.S. subsidiaries had U.S. federal and state net operating loss ("NOL") carry forwards of approximately $50.6 million and $50.2 million, respectively. These NOLs are available for offset against future taxable income and expire between 2017 and 2036. Of the $50.6 million U.S. federal NOLs, approximately $22.8 million is currently available for offset against future U.S. federal taxable income. Of the $50.6 million U.S. federal NOLs, approximately $16.1 million would be recorded in additional paid in capital upon utilization. Of the $50.2 million of state NOLs, approximately $30.9 million would be recorded in additional paid in capital upon utilization. The subsidiary's ability to use the U.S. federal and state NOL carry forwards is limited on an annual basis due to changes of ownership in 2000, 2010 and 2014, as defined by Section 382 of the Internal Revenue Code of 1986, as amended. Of the U.S. federal NOLs, $28.6 million are limited by Section 382. Of the $28.6 million of losses, the amount available during 2016 totaled $2.9 million. The remaining losses are available as follows: $12.8 million for the years 2017 – 2019, $7.7 million in 2020-2022, $5.2 million for the years 2023 – 2026. The expected expiry dates of these losses are as follows: Federal State NOL's NOL's (in thousands) 2017-2018 226 - 2021-2034 34,735 29,049 2035-2036 15,626 21,119 $ 50,587 $ 50,168 In addition US subsidiaries have alternative minimum tax credit carry forwards of approximately $0.4 million that are available to reduce future U.S. federal regular income taxes, over an indefinite period. They also have general business credit carry forwards of approximately $0.3 million that are available to offset future U.S. federal income taxes. The valuation allowance at December 31, 2016 was approximately $20.3 million. The valuation allowance for deferred tax assets as of December 31, 2015 and December 31, 2014 was $17.2 million and $23.1 million respectively. The net change in the total valuation allowance was an increase of $3.1 million during 2016 and a decrease of $5.9 million during 2015. Of the total increase of $3.1 million in 2016, $1.2 million resulted in a current year income tax expense, $2.4 million was acquired and impacted goodwill, and these were offset by a decrease of $0.5 million recognized in Other Comprehensive Income. Of the total decrease of $5.9 million in 2015, $4.1 million resulted in a current year income tax benefit with the remaining decrease of $1.8 million recognized in Other Comprehensive Income. The valuation allowances at December 31, 2016 and December 31, 2015 were primarily related to operating losses and tax credits carried forward that, in the judgment of management, are not more likely than not to be realized. In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. Management considers the scheduled reversal of deferred tax liabilities and projected future taxable income in making this assessment. In respect of deferred tax assets not subject to a valuation allowance, management considers that it is more likely than not that these deferred tax assets will be realized on the basis that there will be sufficient reversals of deferred tax liabilities and taxable income in future periods. During 2015, a UK subsidiary utilized losses for which a full beginning-of-year valuation allowance had been retained resulting in a tax benefit of $3.2 million. During 2016, there were no movements to valuation allowance that had a material impact on the effective tax rate. The Company has not recognized a deferred tax liability for the undistributed earnings of foreign subsidiaries that arose in 2016 and prior years as the Company considers these earnings to be indefinitely reinvested. It is not practicable to calculate the exact unrecognized deferred tax liability, however it is not expected to be material as Ireland allows a tax credit in respect of distributions from foreign subsidiaries at the statutory tax rate in the jurisdiction of the subsidiary so that no material tax liability would be expected to arise in the event these earnings were ever remitted. In addition, withholding taxes applicable to remittances from foreign subsidiaries would not be expected to be material given Ireland's tax treaty network and the EU parent subsidiary directive. A reconciliation of the beginning and ending amount of total unrecognized tax benefits is as follows: December 31, December 31, December 31, 2016 2015 2014 (in thousands) Unrecognized tax benefits at start of year $ 28,166 $ 23,201 $ 5,780 Increase related to acquired tax positions - 778 14,552 Increase related to prior year tax positions 1,151 1,482 565 Decrease related to prior year tax positions (2,483 ) (315 ) (183 ) Increase related to current year tax positions 1,104 3,063 3,709 Settlements (837 ) - (2 ) Lapse of statute of limitations (481 ) (43 ) (1,220 ) Unrecognized tax benefits at end of year $ 26,620 $ 28,166 $ 23,201 The relevant statute of limitations for unrecognized tax benefits totaling $4.9 million could potentially expire during 2017. There was no movement Included in the balance of total unrecognized tax benefits at December 31, 2016 were potential benefits of $26.6 million, which if recognized, would affect the effective rate on income tax from continuing operations. The balance of total unrecognized tax benefits at December 31, 2015 and December 31, 2014 included potential benefits which, if recognized, would affect the effective rate of income tax from continuing operations of $28.2 million and $23.2 million respectively. Interest and penalties recognized as a net expense during the year ended December 31, 2016 amounted to $0.1 million (2015: net expense of $0.9 million, 2014: net benefit of $0.2 million) and are included within the provision for income taxes. Total accrued interest and penalties as of December 31, 2016 and December 31, 2015 were $3.3 million and $3.3 million respectively and are included in closing income taxes payable at those dates. Our major tax jurisdictions are the United States and Ireland. We may potentially be subjected to tax audits in both our major jurisdictions. In the United States tax periods open to audit include the years ended December 31, 2013, December 31, 2014, December 31, 2015 and December 31, 2016. In Ireland, tax periods open to audit include the years ended December 31, 2012, December 31, 2013, December 31, 2014, December 31, 2015 and December 31, 2016. During such audits, local tax authorities may challenge the positions taken by us in tax returns.

Restructuring and other items

Restructuring and other items	12 Months Ended
	Dec. 31, 2016
Restructuring and other items	14. Restructuring and other items Restructuring and other items recognized during the year ended December 31, 2016 comprise: Year Ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Restructuring charges $ 8,159 - $ 8,796 Net charge $ 8,159 - $ 8,796 Restructuring Charges A restructuring charge of $8.2 million was recognized during the year ended December 31, 2016 under a restructuring plan adopted following a review by the Company of its operations. The restructuring plan includes resource rationalizations in certain areas of the business to improve resource utilization, resulting in a charge of $6.2 million and office consolidation resulting in the recognition of an onerous lease obligation of $2.0 million. Workforce Onerous reductions Lease Total (in thousands) Total provision recognized $ 6,190 $ 1,969 $ 8,159 Utilized (5,734 ) (571 ) (6,305 ) Foreign exchange (63 ) - (63 ) Provision at December 31, 2016 $ 393 $ 1,398 $ 1,791 Prior Period Restructuring Charges A restructuring charge of $8.8 million was recognized during the year ended December 31, 2014. Following the closure of the Company's European Phase 1 services in 2013, the Company recognized a charge in 2014 in relation to its Manchester, United Kingdom facility; $5.6 million in relation to asset impairments and $3.2 million in relation to an onerous lease charge associated with this facility. We expect this to be paid by 2024. Onerous Asset Lease Impairment Total (in thousands) Total provision recognized $ 3,167 $ 5,629 $ 8,796 Asset write-off - (5,629 ) (5,629 ) Provision at December 31, 2014 $ 3,167 - $ 3,167 Utilized (1,167 ) - (1,167 ) Provision at December 31, 2015 2,000 - 2,000 Utilized (1,359 ) - (1,359 ) Provision at December 31, 2016 641 - 641 The total onerous lease obligation at December 31, 2016 is $2.0 million and is included within other liabilities.

Provision for Doubtful Debts

Provision for Doubtful Debts	12 Months Ended
	Dec. 31, 2016
Provision for Doubtful Debts	15. Provision for Doubtful Debts The Company does business with most major international pharmaceutical companies. Provision for doubtful debts at December 31, 2016 comprises: December 31, December 31, 2016 2015 (in thousands) Opening provision $ 10,383 $ 5,458 Amounts used during the year (3,782 ) (161 ) Amounts provided during the year 4,651 7,572 Amounts released during the year (1,814 ) (2,244 ) Translation 12 (242 ) Closing provision $ 9,450 $ 10,383

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies	16. Commitments and Contingencies Litigation The Company is not party to any litigation or other legal proceedings that the Company believes could reasonably be expected to have a material adverse effect on the Company's business, results of operations and financial condition. Operating Leases The Company has several non-cancelable operating leases, primarily for facilities, that expire over the next 10 years. These leases generally contain renewal options and require the Company to pay all executory costs such as maintenance and insurance. The Company recognized $44.0 million, $49.9 million and $54.3 million in rental expense, including rates, for the years ended December 31, 2016, December 31, 2015 and December 31, 2014 respectively. Future minimum rental commitments for operating leases with non-cancelable terms in excess of one year are as follows: Minimum rental payments (in thousands) 2017 34,682 2018 28,219 2019 21,358 2020 15,646 2021 12,477 Thereafter 40,132 Total $ 152,514

Business Segment and Geographic

Business Segment and Geographical Information	12 Months Ended
	Dec. 31, 2016
Business Segment and Geographical Information	17. Business Segment and Geographical Information The Company is a contract research organization ("CRO"), providing outsourced development services on a global basis to the pharmaceutical, biotechnology and medical device industries. It specializes in the strategic development, management and analysis of programs that support all stages of the clinical development process - from compound selection to Phase I-IV clinical studies. The Company has the expertise and capability to conduct clinical trials in most major therapeutic areas on a global basis and has the operational flexibility to provide development services on a stand-alone basis or as part of an integrated "full service" solution. The Company has expanded predominately through internal growth, together with a number of strategic acquisitions to enhance its expertise and capabilities in certain areas of the clinical development process. The Company determines and presents operating segments based on the information that is internally provided to the Chief Executive Officer, Chief Financial Officer and Chief Operating Officer, who together are considered the Company's chief operating decision maker, in accordance with FASB ASC 280-10 Disclosures about Segments of an Enterprises and Related Information We have determined that we operate in one Revenues are allocated to individual entities based on where the work is performed in accordance with the Company's global transfer pricing model. Revenues and income from operations in Ireland are a function of this transfer pricing model. Given ICON Clinical Research Limited's ("ICON Ireland") role in the development and management of the group, it's ownership of key intellectual property, customer relationships, its key role in the mitigation of risks faced by the group, plus the responsibility for maintaining the group's global network, ICON Ireland acts as the group entrepreneur and enters into the majority of the Company's customer contracts. As such, ICON Ireland remunerates most of the other operating entities ("cost plus service providers") in the ICON Group on the basis of a guaranteed cost plus mark up for the services they perform in each of their local territories. The cost plus mark up for each ICON entity is established to ensure that each of ICON Ireland and the ICON entities in the various geographical areas that are involved in the conduct of services for customers, earn an appropriate arms-length return having regard to the assets owned, risks borne and functions performed by each entity from these intercompany transactions. The cost plus mark-up policy is reviewed annually to ensure that it is market appropriate. Under this method, the residual operating profits (or losses) of the group, once the cost plus service providers have been paid their respective intercompany service fee are retained by ICON Ireland. The geographic split of revenue disclosed for each region outside Ireland is the cost plus revenue attributable to these entities. The revenues disclosed as relating to Ireland are the net revenues after deducting the cost plus revenues attributable to the activities performed outside Ireland. The Company's areas of operation outside of Ireland include the United States, United Kingdom, Belgium, France, Germany, Italy, Spain, The Netherlands, Sweden, Turkey, Poland, Czech Republic, Latvia, Russia, Ukraine, Hungary, Israel, Romania, Switzerland, Canada, Mexico, Brazil, Colombia, Argentina, Chile, Peru, India, China, South Korea, Japan, Thailand, Taiwan, Singapore, The Philippines, Australia, New Zealand, and South Africa. There have been no changes to the basis of segmentation or the measurement basis for the segment results since the prior year. Reportable a) The distribution of net revenue by geographical area was as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Ireland $ 410,572 $ 429,631 $ 360,376 Rest of Europe 313,185 330,487 372,634 U.S. 763,821 650,941 605,815 Other 178,909 163,919 164,491 Total $ 1,666,487 $ 1,574,978 $ 1,503,316 b) The distribution of income from operations, including restructuring and other items, by geographical area was as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Ireland $ 216,149 $ 189,035 $ 138,185 Rest of Europe 34,200 38,166 14,481 U.S. 41,348 45,320 39,058 Other 19,997 9,015 10,626 Total $ 311,694 $ 281,536 $ 202,350 c) The distribution of income from operations, excluding restructuring and other items, by geographical area was as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Ireland $ 218,334 $ 189,035 $ 138,185 Rest of Europe 36,509 38,166 23,277 U.S. 44,590 45,320 39,058 Other 20,420 9,015 10,626 Total $ 319,853 $ 281,536 $ 211,146 d) The distribution of property, plant and equipment, net, by geographical area was as follows: December 31, December 31, 2016 2015 (in thousands) Ireland $ 105,684 $ 101,736 Rest of Europe 6,231 7,334 U.S. 29,428 34,520 Other 7,624 6,628 Total $ 148,967 $ 150,218 e) The distribution of depreciation and amortization by geographical area was as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Ireland $ 25,766 $ 22,100 $ 20,731 Rest of Europe 6,914 11,055 7,478 U.S. 23,462 20,106 20,491 Other 3,433 4,416 3,842 Total $ 59,575 $ 57,677 $ 52,542 f) The distribution of total assets by geographical area was as follows: December 31, December 31, 2016 2015 * (in thousands) Ireland $ 766,120 $ 663,060 Rest of Europe 337,062 343,733 U.S. 651,160 641,769 Other 71,501 68,647 Total $ 1,825,843 $ 1,717,209 * The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs. g) The distribution of capital expenditures by geographical area was as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Ireland $ 27,670 $ 30,900 $ 15,117 Rest of Europe 2,851 1,916 2,278 U.S. 8,432 15,256 12,224 Other 3,648 1,658 3,160 Total $ 42,601 $ 49,730 $ 32,779 h) The following table sets forth the clients which represented 10% or more of the Company's net revenue in each of the periods set out below. Year ended December 31, December 31, December 31, 2016 2015 2014 Client A 26 % 31 % 31 % i) The distribution of interest income by geographical area was as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Ireland $ 407 $ 102 $ 284 Rest of Europe 1,040 1,151 798 U.S. 2 4 - Other 35 49 69 Total $ 1,484 $ 1,306 $ 1,151 j) The distribution of the income tax charge by geographical area was as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Ireland $ 24,215 $ 21,795 $ 18,384 Rest of Europe 5,528 8,007 2,855 U.S. 8,381 3,580 4,860 Other (131 ) 5,929 4,149 Total $ 37,993 $ 39,311 $ 30,248

Supplemental Disclosure of Cash

Supplemental Disclosure of Cash Flow Information	12 Months Ended
	Dec. 31, 2016
Supplemental Disclosure of Cash Flow Information	18. Supplemental Disclosure of Cash Flow Information Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Cash paid for interest $ 13,615 $ 2,175 $ 533 Cash paid for income taxes $ 10,205 $ 14,829 $ 17,829

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income	12 Months Ended
	Dec. 31, 2016
Accumulated Other Comprehensive Income	19. Accumulated Other Comprehensive Income December 31, December 31, 2016 2015 (in thousands) Currency translation adjustments $ (70,154 ) $ (57,315 ) Currency impact on long term funding (Net of tax) (13,912 ) (5,484 ) Actuarial loss on defined benefit pension plan (note 9) (5,905 ) (3,420 ) Unrealized capital gain/(loss) – investments (note 3) (23 ) (34 ) Net realized gain on interest rate hedge 3,694 4,617 Total $ (86,300 ) $ (61,636 )

Long-Term Debt - Senior Notes

Long-Term Debt - Senior Notes	12 Months Ended
	Dec. 31, 2016
Long-Term Debt - Senior Notes	20. Long-Term Debt – Senior Notes In December 2015 the Company issued $350 million in the private placement market. The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs ($1,694,000). The interest rate in respect of the Senior Notes is fixed at 3.64% for the five year term of the agreement. The associated interest cost is recognized in interest expense in the period since drawdown in December 2015. In October 2015, the Company entered into an interest rate hedge in respect of the planned issuance of the Senior Notes in December 2015. The interest rate hedge matured in November 2015 when the interest rate on the Senior Notes was fixed. The interest rate hedge was effective in accordance with Financial Accounting Standards Board ("FASB") ASC 815, "Derivatives and Hedging". The cash proceeds ($4.6 million), representing the realized gain on the interest rate hedge, were received on maturity in November 2015 and are recorded within Other Comprehensive Income. The realized gain is being amortized to the income statement, net against interest payable, over the period of the Senior Notes. The Senior Notes agreement also includes certain financial covenants that require compliance with a consolidated leverage ratio, a minimum EBIT to consolidated net interest charge ratio and a maximum amount of priority debt, each of which are defined in the Note Purchase and Guarantee Agreement. The Senior Notes have not been, and will not be, registered under the Securities Act of 1933, as amended, and may not be offered or sold in the United States absent registration or an applicable exemption from registration requirements.

Impact of New Accounting Pronou

Impact of New Accounting Pronouncements	12 Months Ended
	Dec. 31, 2016
Impact of New Accounting Pronouncements	21. Impact of New Accounting Pronouncements ASU 2015-03 'Interest-Imputation of Interest' was issued in April 2015 to simplify the presentation of debt issuance costs. The guidance requires debt issuance costs related to term loans to be presented as a direct deduction from the carrying amount of the associated debt liability. The new guidance is reflected in the Consolidated Financial Statements including application on a retrospective basis. The Consolidated Balance Sheet at December 31, 2015 has therefore been restated to reflect the accounting standards update. ASU 2015-16 'Business Combinations' was issued in February 2016 to simplify the accounting and presentation for changes in provisional amounts accounted for in a business combination during the measurement period. The amendments require that an acquirer recognize adjustments to provisional amounts that are identified during the measurement period in the reporting period in which the adjustment amounts are determined. The amendments require that the acquirer record, in the same period's financial statements, the effect on earnings of changes in depreciation, amortization or other income effects, if any, as a result of the change to the provisional accounts, calculated as if the accounting had been completed at the acquisition date. See Note 4 for details of the impact of adoption. In July 2015, the FASB issued ASU 2015-11, which, for entities that do not measure inventory using the last-in, first-out (LIFO) or retail inventory method, changes the measurement principle for inventory from the lower of cost or market to lower of cost and net realizable value. The ASU also eliminates the requirement for these entities to consider replacement cost or net realizable value less an approximately normal profit margin when measuring inventory. In May 2014, the FASB issued ASU 2014-09 ("ASU 2014-09"), Revenue from Contracts with Customers, which provides 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 updated standard will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective and permits the use of either the retrospective or cumulative effect transition method. To achieve the core principle of the new standard, an entity should apply the following steps: (1) identify the contract(s) with a customer; (2) identify the performance obligations in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligations in the contract; and (5) recognize revenue when (or as) the entity satisfies a performance obligation. As originally issued, ASU 2014-09 will be effective prospectively for fiscal years and interim periods within those years beginning after December 15, 2016. On July 9, 2015, the FASB approved the proposal to defer the effective date of this standard by one year. Early adoption is permitted for annual periods beginning after December 16, 2016. Subsequent to issuing ASU 2014-09, the FASB issued the following amendments concerning clarification of ASU 2014-09. In March 2016, the FASB issued ASU 2016-08 ("ASU 2016-08"), Revenue from Contracts with Customers (Topic 606), Principal versus Agent Considerations (Reporting Revenue Gross versus Net), which further clarifies the implementation guidance on principal versus agent considerations. The new guidance requires either a retrospective or a modified retrospective approach to adoption. In April 2016, the FASB issued ASU 2016-10, ("ASU 2016-10") Revenue from Contracts with Customers (Topic 606), Identifying Performance Obligations and Licensing, which clarifies the identification of performance obligations and the licensing implementation guidance, while retaining the related principles for those areas. In May 2016, the FASB issued ASU 2016-12 ("ASU 2016-12"), Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients, which provides clarification on assessing the collectability criterion, presentation of sales taxes, measurement date for noncash consideration and completed contracts at transition. The updated standard is effective for us in the first quarter of the year-ended 31 December 2018. We are continuing to evaluate a method of transition and are currently evaluating the effect that the updated standard will have on our consolidated financial statements and related disclosures. While we are continuing to assess all potential impacts of the new standard, we currently believe the most significant impact relates to our assessment of measurement of performance and percentage of completion. Under current GAAP, the revenue attributable to performance is determined based on both input and output methods of measurement. .Due to the complexity of certain of our contracts, the actual revenue recognition treatment required under the new standard for these arrangements may be dependent on contract-specific terms and vary in some instances. Our preparatory work is also focused on the increased disclosure obligations (including in respect of retrospective revenue and backlog). In January 2016, the FASB issued ASU 2016-01, which will significantly change the income statement impact of equity investments and the recognition of changes in fair value of financial liabilities when the fair value option is elected. The ASU is effective for public business entities for interim and annual periods in fiscal years beginning after December 15, 2017. The adoption of ASU 2016-01 is not expected to have a significant impact on the financial statements. In February 2016, the FASB issued ASU 2016-02, Leases, requiring lessees to recognize a right-of-use asset and a lease liability on the balance sheet for all leases with the exception of short-term leases. For lessees, leases will continue to be classified as either operating or finance leases in the income statement. Lessor accounting is similar to the current model but updated to align with certain changes to the lessee model. Lessors will continue to classify leases as operating, direct financing or sales-type leases. The effective date of the new standard for public companies is for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. Early adoption is permitted. The new standard must be adopted using a modified retrospective transition and requires application of the new guidance at the beginning of the earliest comparative period presented. The updated standard is effective for us beginning in the first quarter of the year-ended December 31, 2019. We are currently evaluating the effect that the updated standard will have on our consolidated financial statements and related disclosures. In March 2016, the FASB issued ASU 2016-04 , Recognition of Breakage for Certain Prepaid Stored-Value Products In March 2016, the FASB issued ASU 2016-05, Effect of Derivative Contract Novations on Existing Hedge Accounting Relationships In March 2016, the FASB issued ASU 2016-06, Contingent Put and Call Options in Debt Instruments In March 2016, the FASB issued ASU 2016-07, Simplifying the Transition In March 2016, the FASB issued ASU 2016-09, Improvements to Employee Share-Based Payment Accounting, which simplifies various aspects related to the accounting and presentation of share-based payments. The amendments require entities to record all tax effects related to share-based payments at settlement or expiration through the income statement and the windfall tax benefit to be recorded when it arises, subject to normal valuation allowance considerations. All tax-related cash flows resulting from share-based payments are required to be reported as operating activities in the statement of cash flows. The updates relating to the income tax effects of the share-based payments including the cash flow presentation must be adopted either prospectively or retrospectively. Further, the amendments allow the entities to make an accounting policy election to either estimate forfeitures or recognize forfeitures as they occur. If an election is made, the change to recognize forfeitures as they occur must be adopted using a modified retrospective approach with a cumulative effect adjustment recorded to opening retained earnings. The effective date of the new standard for public companies is for fiscal years beginning after December 15, 2016 and interim periods within those fiscal years. We will apply the updated standard in the first quarter of the year-ended December 31, 2017. We believe the new standard will cause limited volatility in our effective tax rates and a resulting impact on our diluted earnings per share due to the tax effects related to share-based payments being recorded in the income statement. The volatility in future periods will depend on our stock price at the awards' vest dates and the number of awards that vest in each period. If the share price at the vest date of an award exceeds the share price at its grant date, an additional tax benefit will be recognized in the income statement, reducing our effective tax rate. Conversely, if the share price at the vest date of an award is lower than the share price at its grant date, an additional tax expense will be recognized in the income statement, increasing our effective tax rate for that period. In June 2016, the FASB issued ASU 2016-13, Measurement of Credit Losses on Financial Instruments In August 2016, the FASB issued ASU 2016-15, Classification of Certain Cash Receipts and Cash Payments ● Debt prepayment or debt extinguishment costs; ● Settlement of zero-coupon bonds; ● Contingent consideration payments made after a business combination; ● Proceeds from the settlement of insurance claims; ● Proceeds from the settlement of corporate-owned life insurance policies, including bank-owned life insurance policies; ● Distributions received from equity method investees; ● Beneficial interests in securitization transactions; and ● Separately identifiable cash flows and application of the predominance principle. The ASU is effective for public business entities for interim and annual periods in fiscal years beginning after December 15, 2017. The adoption of ASU 2016-15 is not expected to have a significant impact on the financial statements. In October 2016, the FASB issued ASU 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory, In October 2016, the FASB issued ASU 2016-17, Consolidation (Topic 810): Interests Held through Related Parties That Are under Common Control, The adoption of ASU 2016-17 is not expected to have an impact on the financial statements. In November 2016, the FASB issued ASU 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash, The adoption of ASU 2016-18 is not expected to have a material impact on the financial statements. In December 2016, the FASB issued ASU 2016-19, Technical Corrections and Improvements

Related Parties

Related Parties	12 Months Ended
	Dec. 31, 2016
Related Parties	22. Related Parties Subsidiaries of the Company earned revenue of $100,000 (2015: $100,000) from Dignity Sciences Limited during the year. Dr. John Climax is Chief Executive Officer and both Dr. John Climax and Dr. Ronan Lambe are Directors and shareholders of Dignity Sciences Limited. $45,700 was recorded as due from Dignity Sciences Limited at December 31, 2016. The contract terms were agreed on an arm's length basis. On July 22, 2016, Mr. Thomas Lynch retired as a Director of the Company, having previously resigned as Chairman of the Company in March 2016. The Company entered into an agreement with a company controlled by Mr. Lynch, for the provision of consultancy services for a period of three years from August 1, 2016, at an agreed fee of €231,750 ($256,315) per annum. €96,560 was recorded as due to Mr. Lynch under the terms of this agreement at December 31, 2016. Mr. Lynch also agreed to certain restrictions that will apply to him during the period of the consultancy agreement including non-disclosure, non-competition and non-solicitation.

Significant Accounting Polici30

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Basis of Consolidation	(a) Basis of consolidation The consolidated financial statements include the financial statements of the Company and all of its subsidiaries. All significant intercompany profits, transactions and account balances have been eliminated. The results of subsidiary undertakings acquired in the period are included in the consolidated statement of operations from the date of acquisition.
Use of Estimates	(b) Use of estimates The preparation of financial statements in conformity with generally accepted accounting principles in the United States requires management to make estimates and judgments 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 reported period. Actual results could differ from those estimates. The principle management estimates and judgments used in preparing the financial statements relate to revenue recognition, taxation, goodwill and business combinations.
Revenue Recognition	(c) Revenue recognition The Company primarily earns revenues by providing a number of different services to its customers. These services, which are integral elements of the clinical development process, include clinical trials management, biometric activities, consulting, imaging, contract staffing, informatics and laboratory services. Contracts range in duration from a number of months to several years. Revenue for services, as rendered, is recognized only after persuasive evidence of an arrangement exists, the sales price is fixed or determinable and collectability is reasonably assured. Clinical trials management revenue is recognized on a proportional performance method. Depending on the contractual terms revenue is either recognized on the percentage of completion method based on the relationship between hours incurred and the total estimated hours of the trial or on the unit of delivery method. Contract costs equate to the product of labor hours incurred and compensation rates. For the percentage of completion method, the input (effort expended) method has been used to measure progress towards completion as there is a direct relationship between input and productivity. Contract revenue is the product of the aggregated labor hours required to complete the specified contract tasks at the agreed contract rates. The Company regularly reviews the estimate of total contract time to ensure such estimates remain appropriate taking into account actual contract stage of completion, remaining time to complete and any identified changes to the contract scope. Remaining time to complete depends on the specific contract tasks, the complexity of the contract and can include geographical site selection and initiation, patient enrollment, patient testing and level of results analysis required. While the Company may routinely adjust time estimates, the Company's estimates and assumptions historically have been accurate in all material respects in the aggregate. Where revenue is recognized on the unit of delivery method, the basis applied is the number of units completed as a percentage of the total number of contractual units. Biometrics revenue is recognized on a fee-for-service method as each unit of data is prepared on the basis of the number of units completed in a period as a percentage of the total number of contracted units. Imaging revenue is recognized on a fee-for-service basis recognizing revenue for each image completed. Consulting revenue is recognized on a fee-for-service basis as each hour of the related service is performed. Contract staffing revenue is recognized on a fee-for-service basis, over the time the related service is performed, or in the case of permanent placement, once the candidate has been placed with the client. Informatics revenue is recognized on a fee-for-service basis. Laboratory service revenue is recognized on a fee-for-service basis. The Company accounts for laboratory service contracts as multiple element arrangements, with contractual elements comprising laboratory kits and laboratory testing, each of which can be sold separately. Sales prices for contractual elements are determined by reference to objective and reliable evidence of their sales price. Revenues for contractual elements are recognized on the basis of the number of deliverable units completed in the period. Contracts generally contain provisions for renegotiation in the event of changes in the scope, nature, duration, or volume of services of the contract. Renegotiated amounts are recognized as revenue by revision to the total contract value arising as a result of an authorized customer change order. The difference between the amount of revenue recognized and the amount billed on a particular contract is included in the balance sheet as unbilled revenue or payments on account. Normally, amounts become billable upon the achievement of certain milestones, for example, target patient enrolment rates, clinical testing sites initiated or case report forms completed. Once the milestone target is reached, amounts become billable in accordance with pre-agreed payment schedules included in the contract or on submission of appropriate billing detail. Such cash payments are not representative of revenue earned on the contract as revenues are recognized over the period in which the specified contractual obligations are fulfilled. Amounts included in unbilled revenue are expected to be collected within one year and are included within current assets. Advance billings to customers, for which revenue has not been recognized, are recognized as payments on account within current liabilities. In the event of contract termination, if the value of work performed and recognized as revenue is greater than aggregate milestone billings at the date of termination, cancellation clauses usually ensure that the Company is paid for all work performed to the termination date.
Reimbursable Expenses	(d) Reimbursable expenses Reimbursable expenses comprise investigator payments and certain other costs which are reimbursed by clients under terms specific to each contract and are deducted from gross revenue in arriving at net revenue. Investigator payments are accrued based on patient enrollment over the life of the contract. Investigator payments are made based on predetermined contractual arrangements, which may differ from the accrual of the expense.
Direct Costs	(e) Direct costs Direct costs consist of compensation, associated employee benefits and share-based payments for project-related employees and other direct project-related costs.
Advertising Costs	(f) Advertising costs All costs associated with advertising and promotion are expensed as incurred. The advertising and promotion costs were $7,167,050, $4,513,750 and $3,563,900 for the years ended December 31, 2016, December 31, 2015 and December 31, 2014 respectively.
Foreign Currencies and Translation of Subsidiaries	(g) Foreign currencies and translation of subsidiaries The Company's financial statements are prepared in United States dollars. Transactions in currencies other than United States dollars are recorded at the rate ruling at the date of the transaction. Monetary assets and liabilities denominated in currencies other than United States dollars are translated into United States dollars at exchange rates prevailing at the balance sheet date. Adjustments resulting from these translations are charged or credited to income. Amounts charged or credited to the statement of operations for the years ended December 31, 2016, December 31, 2015 and December 31, 2014 were as follows: Year ended December 31, (in thousands) 2016 2015 2014 Amounts charged/(credited) $ 2,094 $ (3,608 ) $ (5,942 ) The financial statements of subsidiaries with other functional currencies are translated at period end rates for the balance sheet and average rates for the statement of operations. Translation gains and losses arising are reported as a movement on accumulated other comprehensive income.
Disclosure About Fair Value of Financial Instruments	(h) Disclosure about fair value of financial instruments Thefollowing methods and assumptions were used to estimate the fair value of each material class of financial instrument: Cash, cash equivalents, unbilled revenue, other receivables, short term investments, prepayments and other current assets, accounts receivable, accounts payable, investigator payments, payments on account, accrued liabilities, accrued bonuses and income taxes payable have carrying amounts that approximate fair value due to the short term maturities of these instruments. Other liabilities' carrying amounts approximate fair value based on net present value of estimated future cash flows. Financial instruments are measured in the statement of financial position at fair value using a fair value hierarchy of valuation inputs. The hierarchy prioritizes the inputs into three levels based on the extent to which inputs used in measuring fair value are observable in the market. Each fair value measurement is reported in one of three levels, which is determined by the lowest level input that is significant to the fair value measurement in its entirety. These levels are: Level 1: Inputs are based upon unadjusted quoted prices for identical instruments traded in active markets. Level 2: Inputs are based upon quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active and model-based valuation techniques for which all significant assumptions are observable in the market or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3: Inputs are generally unobservable and typically reflect management’s estimates of assumptions that market participants would use in pricing the asset or liability. The Company classifies its short term investments as available for sale, as it does not actively trade such securities nor does it intend to hold them to maturity. The fair value of short term investments are represented by level 1 fair value measurements – quoted prices in active markets for identical assets. The unrealized movements in fair value are recognized in equity until disposal or sale, at which time, those unrealized movements from prior periods are recognized in profit or loss. For losses other than temporary, which reduce the carrying amount below cost is recognized in profit or loss.
Business Combinations	(i) Business combinations The cost of a business combination is measured as the aggregate of the fair values at the date of exchange of assets given, liabilities incurred or assumed and equity instruments issued in exchange for control. Where a business combination agreement provides for an adjustment to the cost of the acquisition which is contingent upon future events, the amount of the estimated adjustment is recognized at the acquisition date at the fair value of the contingent consideration. Any changes to this estimate outside the measurement period will depend on the classification of the contingent consideration. If the contingent consideration is classified as equity it shall not be re-measured and the settlement shall be accounted for within equity. If the contingent consideration is classified as a liability any adjustments will be accounted for through the Consolidated Statement of Operations or Other Comprehensive Income depending on whether the liability is considered a financial instrument. The assets, liabilities and contingent liabilities of businesses acquired are measured at their fair values at the date of acquisition. In the case of a business combination which is completed in stages, the fair values of the identifiable assets, liabilities and contingent liabilities are determined at the date of each exchange transaction. When the initial accounting for a business combination is determined provisionally, any subsequent adjustments to the provisional values allocated to the identifiable assets, liabilities and contingent liabilities are made within twelve months of the acquisition date and presented as adjustments to goodwill in the reporting period in which the adjustments are determined.
Goodwill and Impairment	(j) Goodwill and Impairment Goodwill represents the excess of the cost of acquired entities over the net amounts assigned to assets acquired and liabilities assumed. Goodwill primarily comprises acquired workforce in place which does not qualify for recognition as an asset apart from goodwill. Goodwill is stated net of any provision for impairment. The Company tests goodwill annually for any impairments or whenever events occur which may indicate impairment. The first step is to compare the carrying amount of the reporting unit's assets to the fair value of the reporting unit. If the carrying amount exceeds the fair value then a second step is completed which involves the fair value of the reporting unit being allocated to each asset and liability with the excess being implied goodwill. The impairment loss is the amount by which the recorded goodwill exceeds the implied goodwill. No impairment was recognized as a result of the impairment testing carried out for the years ended December 31, 2016, December 31, 2015 and December 31, 2014.
Intangible Assets	(k) Intangible assets Intangible assets are amortized on a straight line basis over their estimated useful life.
Cash and Cash Equivalents	(l) Cash and cash equivalents Cash and cash equivalents include cash and highly liquid investments with initial maturities of three months or less and are stated at cost, which approximates market value.
Short Term Investments - Available for Sale	(m) Short term investments - available for sale The Company classifies short-term investments as available for sale in accordance with the terms of FASB ASC 320, Investments – Debt and Equity Securities
Inventory	(n) Inventory Inventory is valued at the lower of cost and market value and after provisions for obsolescence. The cost of inventories comprises the purchase price and attributable costs, less trade discounts. At December 31, 2016 the carrying value of inventory, included within prepayments and other current assets on the balance sheet, was $2.4 million (2015: $1.8 million).
Property, Plant and Equipment	(o) Property, plant and equipment Property, plant and equipment is stated at cost less accumulated depreciation. Depreciation of property, plant and equipment is computed using the straight line method based on the estimated useful lives of the assets as listed below: Years Building 40 Computer equipment and software 2-8 Office furniture and fixtures 8 Laboratory equipment 5 Motor vehicles 5 Leasehold improvements are amortized using the straight-line method over the estimated useful life of the asset or the lease term, whichever is shorter.
Leased Assets	(p) Leased assets Costs in respect of operating leases are charged to the statement of operations on a straight line basis over the lease term. Assets acquired under capital finance leases are included in the balance sheet at the present value of the future minimum lease payments and are depreciated over the shorter of the lease term and their remaining useful lives. The corresponding liabilities are recorded in the balance sheet and the interest element of the capital lease rental is charged to interest expense.
Income Taxes	(q) Income taxes The Company applies the asset and liability method of accounting for income taxes. Under the asset and liability method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which these temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. The Company recognizes the effect of income tax positions only if those positions will more likely than not be sustained. Recognized income tax positions are measured at the largest amount of tax benefit that is greater than 50 percent likely of being realized upon settlement. Interest and penalties related to income taxes are included in income tax expense and classified with the related liability on the consolidated balance sheet. On November 21, 2015 FASB issued ASU 2015-17 on the balance sheet classification of deferred taxes. The new standard requires that all deferred taxes are presented as non-current in a classified Statement of Financial Position. The new guidance is effective for public business entities for annual periods beginning after December 15, 2016 and for non-public business entities for annual periods beginning after December 15, 2017. Early adoption is available for all entities for any set of financial statements that had not been released as at November 21, 2015 with an option to apply on either a prospective or a retrospective basis. The Company elected for early adoption of ASU 2015 – 17 on a prospective basis for all financial statements issued after November 21, 2015. The effect of this is that all deferred tax assets and liabilities are classified as non-current assets and liabilities in the December 31, 2016 and December 31, 2015 balance sheets.
Government Grants	(r) Government grants Government grants received relating to capital expenditures are shown as deferred income and credited to income on a basis consistent with the depreciation policy of the relevant assets. Grants relating to categories of operating expenditures are credited to income in the period in which the expenditure to which they relate is charged. Under the grant agreements amounts received may become repayable in full should certain circumstances specified within the grant agreements occur, including downsizing by the Company, disposing of the related assets, ceasing to carry on its business or the appointment of a receiver over any of its assets. The Company has not recognized any loss contingency having assessed as remote the likelihood of these events arising.
Research and Development Credits	(s) Research and development credits Research and development credits are available to the Company under the tax laws in certain jurisdictions, based on qualifying research and development spend as defined under those tax laws. Research and development credits are generally recognized as a reduction of income tax expense. However, certain tax jurisdictions provide refundable credits that are not wholly dependent on the Company's ongoing income tax status or income tax position. In these circumstances the benefit of these credits is not recorded as a reduction to income tax expense, but rather as a reduction of operating expenditure.
Pension Costs	(t) Pension costs The Company contributes to defined contribution plans covering all eligible employees. The Company contributes to these plans based upon various fixed percentages of employee compensation and such contributions are expensed as incurred. The Company operates, through a subsidiary, a defined benefit plan for certain of its United Kingdom and Swiss employees. The Company accounts for the costs of these plans using actuarial models required by FASB ASC 715-30 and these plans are presented in accordance with the requirements of FASB ASC 715-60 Defined Benefit Plans – Other Post retirement
Net Income per Ordinary Share	(u) Net income per ordinary share Basic net income per ordinary share has been computed by dividing net income available to ordinary shareholders by the weighted average number of ordinary shares outstanding during the period. Diluted net income per ordinary share is computed by adjusting the weighted average number of ordinary shares outstanding during the period for all potentially dilutive ordinary shares outstanding during the period and adjusting net income for any changes in income or loss that would result from the conversion of such potential ordinary shares. There is no difference in net income used for basic and diluted net income per ordinary share. The reconciliation of the number of shares used in the computation of basic and diluted net income per ordinary share is as follows: Year Ended December 31, 2016 2015 2014 Weighted average number of ordinary shares outstanding for basic net income per ordinary share 55,248,900 58,746,935 61,496,115 Effect of dilutive share options outstanding 1,158,236 1,543,098 1,635,302 Weighted average number of ordinary shares outstanding for diluted net income per ordinary share 56,407,136 60,290,033 63,131,417
Share-Based Compensation	(v) Share-based compensation The Company accounts for its share options, restricted share units ("RSUs") and performance share units ("PSUs") in accordance with the provisions of FASB ASC 718, Compensation – Stock Compensation. Share-based compensation expense for share options awarded to employees and Directors is estimated at the grant date based on each option's fair value as calculated using the Black-Scholes option-pricing model. Share-based compensation for RSUs and PSUs awarded to employees and Directors is calculated based on the market value of the Company's shares on the date of award of the RSUs and PSUs. The value of awards expected to vest is recognized as an expense over the requisite service periods. Forfeitures are estimated on the date of grant and revised if actual or expected forfeiture activity differs materially from original estimates. Estimating the grant date fair value of share options as of the grant date using an option-pricing model, such as the Black-Scholes model, is affected by the Company's share price as well as assumptions regarding a number of complex variables. These variables include, but are not limited to, the expected share price volatility over the term of the awards, risk-free interest rates and the expected term of the awards.
Impairment of Long-Lived Assets	(w) Impairment of long-lived assets Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of the asset to future undiscounted net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured at the amount by which the carrying amount of the asset exceeds the fair value of the asset. Assets to be disposed of are reported at the lower of the carrying amount of the asset or fair value less selling costs.
Derivative Financial Instruments	(x) Derivative financial instruments We enter into transactions in the normal course of business using various financial instruments in order to hedge against exposure to fluctuating exchange and interest rates. We use derivative financial instruments to reduce exposure to fluctuations in interest rates. A derivative is a financial instrument or other contract whose value changes in response to some underlying variable, which has an initial net investment smaller than would be required for other instruments that have a similar response to the variable and that will be settled at a future date. We do not enter into derivative financial instruments for trading or speculative purposes. We did not hold any interest rate swap contracts or forward currency contracts at December 31, 2016, December 31, 2015 or December 31, 2014. Our accounting policies for derivative financial instruments are based on whether they meet the criteria for designation as cash flow or fair value hedges. A designated hedge of the exposure to variability in the future cash flows of an asset or a liability, or of a forecasted transaction, is referred to as a cash flow hedge. A designated hedge of the exposure to changes in fair value of an asset or a liability is referred to as a fair value hedge. The criterion for designating a derivative as a hedge includes the assessment of the instrument's effectiveness in risk reduction, matching of the derivative instrument to its underlying transaction and the probability that the underlying transaction will occur. For derivatives with cash flow hedge accounting designation, we report the gain or loss from the effective portion of the hedge as a component of Other Comprehensive Income and reclassify it into earnings in the same period or periods in which the hedged transaction affects earnings and within the same income statement line item as the impact of the hedged transaction. For derivatives with fair value hedge accounting designation, we recognize gains or losses from the change in fair value of these derivatives, as well as the offsetting change in the fair value of the underlying hedged item, in earnings. Fair value gains and losses arising on derivative financial instruments not qualifying for hedge accounting are reported in our Consolidated Statement of Operations.
Financing Costs and Gain on Interest Rate Hedge	(y) Financing costs and gain on interest rate hedge The interest rate in respect of the Senior Notes is fixed at 3.64% for the five year term of the agreement. The associated interest cost is recognized in interest expense in the period since drawdown in December 2015. On October 5, 2015, the Company entered into an interest rate hedge in respect of the planned issuance of the Senior Notes in December 2015. The interest rate hedge matured on November 17, 2015 when the interest rate on the Senior Notes was fixed. The interest rate hedge was effective in accordance with Financial Accounting Standards Board ("FASB") ASC 815, "Derivatives and Hedging". The cash proceeds ($4.6 million), representing the realized gain on the interest rate hedge, were received on maturity in November 2015 and are recorded within Other Comprehensive Income. The realized gain will be amortized to the income statement, net against interest payable, over the period of the Senior Notes. Deferred financing costs (including issue costs relating to the Senior Notes) are reported at cost less accumulated amortization and the related amortization expense is included in interest expense, in our consolidated statement of income.
Reclassifications	(z) Reclassifications Certain amounts in the consolidated financial statements have been reclassified where necessary to conform to the current year presentation.

Significant Accounting Polici31

Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2016
Adjustments Resulting From Foreign Currency Translations	Amounts charged or credited to the statement of operations for the years ended December 31, 2016, December 31, 2015 and December 31, 2014 were as follows: Year ended December 31, (in thousands) 2016 2015 2014 Amounts charged/(credited) $ 2,094 $ (3,608 ) $ (5,942 )
Estimated Useful Lives of Assets	Property, plant and equipment is stated at cost less accumulated depreciation. Depreciation of property, plant and equipment is computed using the straight line method based on the estimated useful lives of the assets as listed below: Years Building 40 Computer equipment and software 2-8 Office furniture and fixtures 8 Laboratory equipment 5 Motor vehicles 5
Reconciliation of Number of Shares Used in Computation of Basic and Diluted Net Income Per Ordinary Share	There is no difference in net income used for basic and diluted net income per ordinary share. The reconciliation of the number of shares used in the computation of basic and diluted net income per ordinary share is as follows: Year Ended December 31, 2016 2015 2014 Weighted average number of ordinary shares outstanding for basic net income per ordinary share 55,248,900 58,746,935 61,496,115 Effect of dilutive share options outstanding 1,158,236 1,543,098 1,635,302 Weighted average number of ordinary shares outstanding for diluted net income per ordinary share 56,407,136 60,290,033 63,131,417

Short term investments - avai32

Short term investments - available for sale (Tables)	12 Months Ended
	Dec. 31, 2016
Cost and Fair Value of Investments	December 31, December 31, 2016 2015 (in thousands) At start of year $ 85,990 $ 97,100 Purchases 22,030 14,194 Sales and maturities (40,858 ) (25,708 ) Interest on short term investments 823 571 Realized gain/(loss) on sale of short term investments 50 (113 ) Unrealized capital gain/(loss) – investments 11 (54 ) At end of year $ 68,046 $ 85,990
Available For Sale Short Term Investments by Major Security Type	The following table represents our available for sale short term investments by major security type as of December 31, 2016: Maturity by period Cost Total Unrealized gains / (losses) Fair Value Total Less than 1 year 1 to 5 years (U.S.$ in millions) US government debt securities 13.98 (0.04 ) 13.94 3.00 10.94 Corporate securities 52.98 0.02 53.00 25.08 27.92 Term deposits 1.11 - 1.11 1.11 - Total (U.S.$ in millions) $ 68.07 $ (0.02 ) $ 68.05 $ 29.19 $ 38.86

Goodwill (Tables)

Goodwill (Tables)	12 Months Ended
	Dec. 31, 2016
Goodwill	December 31, December 31, 2016 2015 (in thousands) Opening goodwill $ 588,434 $ 463,324 Current year acquisitions (note 4 (a)) 34,576 133,123 Prior period acquisition (note 4(b)) 7,689 4,418 Foreign exchange movement (14,611 ) (12,431 ) Closing goodwill $ 616,088 $ 588,434
Clinical Research Management Inc.
Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed	The table following summarizes the Company's provisional estimates of the fair values of the assets acquired and liabilities assumed: September 15, 2016 (in thousands) Cash $ 3,168 Property, plant and equipment 939 Goodwill* 34,576 Intangible assets** 8,644 Accounts receivable 11,725 Unbilled revenue 2,814 Prepayments and other current assets 1,673 Accounts payable (621 ) Other liabilities (4,515 ) Non-current other liabilities (7 ) Net assets acquired $ 58,396 Cash consideration 52,396 Contingent consideration $ 6,000 Net purchase consideration $ 58,396 *Goodwill represents the acquisition of an established workforce with experience in preclinical through Phase IV support of clinical research and clinical trial services for biologics, drugs and devices. Goodwill related to the US portion of the business acquired is tax deductible. **The Company has made an initial estimate of separate intangible assets (comprised of customer relationships and order book) acquired of $8.6 million. This assessment is under review and will be finalized within 12 months of the date of acquisition.
Proforma Effect in Net Revenue Net Income and Earnings Per Share	The proforma effect of the ClinicalRM acquisition if completed on January 1, 2015 would have resulted in net revenue, net income and earnings per share for the fiscal years ended December 31, 2016 and December 31, 2015 as follows: Year Ended December 31, 2016 2015 (in thousands) Net revenue $ 1,713,245 $ 1,639,085 Net income $ 266,148 $ 244,167 Basic earnings per share $ 4.82 $ 4.16 Diluted earnings per share $ 4.72 $ 4.05
PMG
Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed	The acquisition of PMG has been accounted for as a business combination in accordance with FASB ASC 805 Business Combinations December 4, 2015 (in thousands) Cash $ 194 Property, plant and equipment 712 Goodwill* 48,728 Customer lists 6,938 Order backlog 2,948 Accounts receivable 11,597 Prepayments and other current assets 1,329 Accounts payable (530 ) Other liabilities (3,456 ) Non-current deferred tax liability (3,106 ) Net assets acquired 65,354 Cash consideration 53,681 Other liabilities assumed 10,060 Working capital adjustment 1,613 Total cash outflows 65,354 *Goodwill represents the acquisition of an established workforce with experience in clinical trial consulting and regulatory support for the development of drugs, medical devices and diagnostics, with a specific focus on strategy to increase efficiency and productivity in product development. In finalizing the goodwill on acquisition of PMG in the twelve month period from acquisition, fair value adjustments were made to deferred tax liabilities ($3.1 million), accounts receivable acquired ($1.4 million), other liabilities ($1.2 million) and the value of the customer list and order backlog assets acquired ($0.4 million). Additional consideration of $1.6 million was provided on completion of the contractual working capital process.
Proforma Effect in Net Revenue Net Income and Earnings Per Share	The proforma effect of the PMG acquisition if completed on January 1, 2014 would have resulted in net revenue, net income and earnings per share for the fiscal years ended December 31, 2015 and December 31, 2014 as follows: Year Ended December 31, 2015 2014 (in thousands) Net revenue $ 1,601,891 $ 1,527,685 Net income $ 243,004 $ 172,390 Basic earnings per share $ 4.14 $ 2.80 Diluted earnings per share $ 4.03 $ 2.73
MediMedia Pharma Solutions
Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed	The acquisition of MediMedia Pharma Solutions has been accounted for as a business combination in accordance with FASB ASC 805 Business Combinations February 27, 2015 (in thousands) Property, plant and equipment $ 1,049 Goodwill* 92,084 Customer lists 22,752 Order backlog 2,521 Accounts receivable 5,240 Unbilled Revenue 4,324 Prepayments and other current assets 621 Accounts payable (749 ) Payments on account (4,186 ) Deferred tax liability (2,171 ) Other liabilities (5,483 ) Net assets acquired $ 116,002 Cash consideration $ 108,717 Other liabilities assumed** 11,283 Gross cash outflows 120,000 Working capital adjustment (3,998 ) Net cash outflows $ 116,002 * Goodwill represents the acquisition of an established workforce with experience in the provision of strategic payer-validated market access solutions while the acquisition of Complete Healthcare Communications comprises an established workforce with significant communication experience working with medical affairs, commercial and brand development teams within the life science industry. Goodwill related to the US portion of the business acquired is tax deductible. ** Payments made at acquisition date of $11.3 million were in respect of certain one-time liabilities at the acquisition date which have subsequently been discharged.
Proforma Effect in Net Revenue Net Income and Earnings Per Share	The proforma effect of the MediMedia Pharma Solutions acquisition if completed on January 1, 2014 would have resulted in net revenue, net income and earnings per share for the fiscal years ended December 31, 2015 and December 31, 2014 as follows: Year Ended December 31, 2015 2014 (in thousands) Net revenue $ 1,581,816 $ 1,556,936 Net income $ 239,361 $ 179,289 Basic earnings per share $ 4.07 $ 2.92 Diluted earnings per share $ 3.97 $ 2.84
Aptiv Solutions
Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed	The acquisition of Aptiv has been accounted for as a business combination in accordance with FASB ASC 805 Business Combinations May 7, 2014 (in thousands) Property, plant and equipment $ 6,924 Goodwill* 125,627 Customer relationships 21,400 Order backlog 7,900 Cash and cash equivalents 3,484 Accounts receivable 25,091 Unbilled revenue 21,154 Prepayments and other current assets 4,180 Non-current assets 2,911 Accounts payable (9,565 ) Other liabilities (29,782 ) Payments on account (31,094 ) Non-current other liabilities (11,303 ) Loan notes payable** (17,790 ) Net assets acquired $ 119,137 Cash consideration $ 143,500 Working capital adjustment (1,964 ) 141,536 Adjustments to cash consideration** (22,399 ) Net purchase consideration $ 119,137 *Goodwill represents the acquisition of an established workforce with experience in clinical trial consulting and regulatory support for the development of drugs, medical devices and diagnostics, with a specific focus on strategy to increase efficiency and productivity in product development. Goodwill related to the US portion of the business acquired is tax deductible. **Adjustments to cash consideration represent certain one-time liabilities (including loan notes) identified at the acquisition date which have subsequently been paid.
Proforma Effect in Net Revenue Net Income and Earnings Per Share	The proforma effect of the Aptiv Solutions acquisition if completed on January 1, 2013 would have resulted in net revenue, net income and earnings per share for the fiscal years ended December 31, 2013 and December 31, 2014 as follows: Year Ended December 31, 2014 2013 (in thousands) Net revenue $ 1,543,820 $ 1,451,682 Net income $ 172,508 $ 101,857 Basic earnings per share $ 2.81 $ 1.67 Diluted earnings per share $ 2.73 $ 1.64

Intangible Assets (Tables)

Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2016
Intangible Assets	December 31, December 31, 2016 2015 Cost (in thousands) Customer relationships acquired $ 87,218 $ 90,541 Technology asset acquired 11,169 11,169 Order backlog 16,540 13,592 Trade names acquired 1,357 1,357 Volunteer list acquired 1,325 1,325 Non-compete arrangements 489 489 ClinicalRM intangible asset 8,644 - Foreign exchange movement (6,578 ) (5,092 ) Total cost 120,164 113,381 Accumulated amortization (67,037 ) (49,587 ) Foreign exchange movement 3,483 2,333 Net book value $ 56,610 $ 66,127
Future Intangible Asset Amortization Expense	Future intangible asset amortization expense for the years ended December 31, 2017 to December 31, 2021 is as follows: Year ended December 31, (in thousands) 2017 $ 15,449 2018 11,815 2019 9,921 2020 9,634 2021 7,597 $ 54,416

Property, Plant and Equipment35

Property, Plant and Equipment, net (Tables)	12 Months Ended
	Dec. 31, 2016
Property Plant and Equipment Net	December 31, December 31, 2016 2015 (in thousands) Cost Land $ 3,464 $ 3,464 Building 77,950 80,861 Computer equipment and software 315,984 282,909 Office furniture and fixtures 70,218 65,152 Laboratory equipment 31,487 31,098 Leasehold improvements 20,933 20,647 Motor vehicles 43 47 520,079 484,178 Less accumulated depreciation and asset write offs (371,112 ) (333,960 ) Property, plant and equipment (net) $ 148,967 $ 150,218

Other Liabilities (Tables)

Other Liabilities (Tables)	12 Months Ended
	Dec. 31, 2016
Other Liabilities	December 31, December 31, 2016 2015 (in thousands) Personnel related liabilities $ 135,349 $ 159,339 Facility related liabilities 14,182 22,517 General overhead liabilities 31,126 29,257 Other liabilities 7,584 18,607 Short term government grants (note 11) 54 43 Restructuring and other items (note 14) 2,432 2,116 $ 190,727 $ 231,879

Other Non-Current Liabilities (

Other Non-Current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2016
Other Non-Current Liabilities	December 31, December 31, 2016 2015 (in thousands) Defined benefit pension obligations, net (note 9) 8,952 7,189 Other non-current liabilities* 14,800 5,035 $ 23,752 $ 12,224 *An amount of $6.0 million is included within other non-current liabilities in respect of contingent consideration for the acquisition of ClinicalRM. See note 4 (a).

Employee Benefits (Tables)

Employee Benefits (Tables) - Foreign Postretirement Benefit Plan	12 Months Ended
	Dec. 31, 2016
UNITED KINGDOM
Pension Costs of Plan	The plan has been closed to new entrants with effect from July 1, 2003. Change in benefit obligation December 31, 2016 December 31, 2015 (in thousands) Benefit obligation at beginning of year $ 27,369 $ 32,875 Service cost 75 78 Interest cost 1,017 1,140 Plan participants' contributions 22 26 Expenses 8 - Benefits paid (104 ) (1,111 ) Actuarial loss/(gain) 10,057 (3,992 ) Foreign currency exchange rate changes (5,538 ) (1,647 ) Benefit obligation at end of year $ 32,906 $ 27,369 Change in plan assets December 31, 2016 December 31, 2015 (in thousands) Fair value of plan assets at beginning of year $ 23,367 $ 25,409 Actual return on plan assets 5,861 277 Employer contributions 108 114 Plan participants' contributions 22 26 Benefits paid (104 ) (1,111 ) Foreign currency exchange rate changes (4,378 ) (1,348 ) Fair value of plan assets at end of year $ 24,876 $ 23,367
Funded Status	Funded status December 31, 2016 December 31, 2015 (in thousands) Projected benefit obligation $ (32,906 ) $ (27,369 ) Fair value of plan assets 24,876 23,367 Funded status $ (8,030 ) $ (4,002 ) Non-current other liabilities (note 8) $ (8,030 ) $ (4,002 )
Components of Net Periodic Benefit Cost	The following amounts were recorded in the consolidated statement of operations as components of the net periodic benefit cost: December 31, 2016 December 31, 2015 December 31, 2014 (in thousands) Service cost $ 75 $ 78 $ 91 Interest cost 1,017 1,140 1,235 Expected return on plan assets (646 ) (661 ) (1,299 ) Amortization of net loss - 224 20 Expenses 8 - 359 Net periodic benefit cost $ 454 $ 781 $ 406
Assumptions Used in Calculating Net Periodic Benefit Cost	The following assumptions were used at the commencement of the year in determining the net periodic pension benefit cost for the years ended December 31, 2014, December 31, 2015 and December 31, 2016: December 31, December 31, December 31, 2016 2015 2014 Discount rate 4.0 % 3.6 % 4.7 % Rate of compensation increase 3.7 % 3.6 % 4.0 % Expected rate of return on plan assets 3.0 % 2.7 % 6.1 % Accumulated other comprehensive income December 31, 2016 December 31, 2015 December 31, 2014 (in thousands) Actuarial loss/(gain) - benefit obligation $ 10,057 $ (3,992 ) $ 8,270 Actuarial (gain)/loss – plan assets (5,215 ) 384 (4,125 ) Actuarial gain recognized in net periodic benefit cost - (224 ) (20 ) Total $ 4,842 $ (3,832 ) $ 4,125
Amounts Recognized in Accumulated Other Comprehensive Income Which Have Not Yet Been Recognized as Components of Net Periodic Benefit Cost	Amounts recognized in accumulated other comprehensive income that have not yet been recognized as components of net periodic benefit cost are as follows: December 31, 2016 December 31, 2015 December 31, 2014 (in thousands) Net actuarial loss $ 7,123 $ 2,281 $ 6,113 Total $ 7,123 $ 2,281 $ 6,113
Assumptions Used in Calculating Pension Benefit Obligations	The following assumptions were used in determining the benefit obligation at December 31, 2016 and December 31, 2015: December 31, December 31, 2016 2015 Discount rate 2.7 % 4.0 % Rate of compensation increase 3.9 % 3.7 %
Expected Long Term Rates of Return on Different Asset Classes	The expected long term rates of return on different asset classes are as follows: Asset Category Expected long-term return per annum Corporate Bonds 2.7 % Gilts 1.9 %
Actual Plan Asset Allocations	The underlying asset split of the fund is shown below. Asset Category December 31, 2016 December 31, 2015 Corporate Bonds 25 % 26 % Gilts 75 % 74 % 100 % 100 %
Annual Benefit Payments which Reflect Expected Future Service	The following annual benefit payments, which reflect expected future service as appropriate, are expected to be paid. (in thousands) 2017 64 2018 65 2019 68 2020 70 2021 73 Years 2022 - 2026 $ 362
SWITZERLAND
Pension Costs of Plan	The pension costs of this plan are presented in the following tables in accordance with the requirements of ASC 715-60, Defined Benefit Plans – Other Postretirement Change in benefit obligation December 31, 2016 December 31, 2015 (in thousands) Benefit obligation at beginning of year 8,537 8,884 Service cost 352 618 Interest cost 82 159 Plan participants' contributions 150 - Settlement (909 ) - Prior service cost (88 ) - Transferred balances/(benefits paid) 53 (1,146 ) Actuarial (gain)/ loss (1,157 ) 81 Foreign currency exchange rate changes (92 ) (59 ) Benefit obligation at end of year 6,928 8,537 Change in plan assets Fair value of plan assets at beginning of year 5,350 7,061 Expected return on plan assets 48 93 Actual return on plan assets 1,233 (1,075 ) Scheme contributions 195 194 Plan participants' contributions 150 216 Transferred balances/(benefits paid) 53 (1,146 ) Settlement (909 ) - Foreign currency exchange rate changes (114 ) 7 Fair value of plan assets at end of year 6,006 5,350
Funded Status	Funded status December 31, 2016 December 31, 2015 (in thousands) Projected benefit obligation $ (6,928 ) $ (8,537 ) Fair value of plan assets 6,006 5,350 Funded status (922 ) (3,187 ) Non-current other liabilities (note 8) $ (922 ) $ (3,187 )
Components of Net Periodic Benefit Cost	December 31, 2016 December 31, 2015 (in thousands) Service cost $ 352 $ 402 Interest cost 82 159 Expected return on plan assets (48 ) (119 ) Amortization of net loss 22 - Amortization of prior service credit (8 ) - Settlement (136 ) - Curtailment loss - 18 Net periodic benefit cost $ 264 $ 460
Assumptions Used in Calculating Net Periodic Benefit Cost	The following assumptions were used at the commencement of the year in determining the net periodic pension benefit cost for the years ended December 31, 2016 and December 31, 2015: December 31, December 31, 2016 2015 Discount rate 0.95 % 1.35 % Rate of compensation increase 2.0 % 2.0 % Expected rate of return on plan assets 0.95 % 1.35 % Accumulated other comprehensive income December 31, 2016 December 31, 2015 Actuarial (gain)/loss - benefit obligation $ (1,157 ) $ 81 Actuarial (gain)/loss – plan assets (1,233 ) 1,075 Prior service credit/(cost) recognized in net periodic benefit cost 136 (17 ) Actuarial loss recognized in net periodic benefit cost (22 ) - Amortization of net prior service credit 8 - Net prior service credit occurring during the year (89 ) - Total $ (2,357 ) $ 1,139
Amounts Recognized in Accumulated Other Comprehensive Income Which Have Not Yet Been Recognized as Components of Net Periodic Benefit Cost	Amounts recognized in accumulated other comprehensive income that have not yet been recognized as components of net periodic benefit cost are as follows: December 31, 2016 December 31, 2015 (in thousands) Net actuarial (gain)/loss $ (1,218 ) $ 1,139 Total $ (1,218 ) $ 1,139
Assumptions Used in Calculating Pension Benefit Obligations	The following assumptions were used in determining the benefit obligation at December 31, 2016 and December 31, 2015: December 31, December 31, 2016 2015 Discount rate 0.75 % 0.95 % Rate of compensation increase 2.0 % 2.0 %
Actual Plan Asset Allocations	The following annual benefit payments, which reflect expected future service as appropriate, are expected to be paid. (in thousands) 2017 305 2018 306 2019 685 2020 251 2021 249 Years 2022 - 2026 $ 1,676
Fair Value, Inputs, Level 1 | UNITED KINGDOM
Plan Asset Fair Value Measurements	Plan Asset Fair Value Measurements Quoted Prices in Active Markets for Identical Assets Level 1 (in thousands) December 31, 2016 December 31, 2015 Cash $ 16 $ 3 Fixed Income Securities Legal and General Active Corporate Bond – Over 10 Year 6,095 6,256 Legal and General Gilt Funds 6,725 6,528 Legal and General Index Linked Gilt Funds 12,040 10,580 $ 24,876 $ 23,367

Equity Incentive Schemes and 39

Equity Incentive Schemes and Stock Compensation Charges (Tables)	12 Months Ended
	Dec. 31, 2016
Transactions for Company's Share Option Plans	The following table summarizes the transactions for the Company's share option plans for the years ended December 31, 2016, December 31, 2015 and December 31, 2014: Options Granted Under Plans Number of Shares Weighted Average Exercise Price Weighted Average Grant Date Fair Value Outstanding at December 31, 2013 2,973,788 2,973,788 $ 24.20 $ 9.57 Granted 366,985 366,985 $ 45.82 $ 14.09 Exercised (926,407 ) (926,407 ) $ 24.02 $ 9.45 Cancelled (186,666 ) (186,666 ) $ 22.17 $ 9.01 Outstanding at December 31, 2014 2,227,700 2,227,700 $ 28.00 $ 10.40 Granted 259,059 259,059 $ 68.25 $ 19.75 Exercised (773,753 ) (773,753 ) $ 27.13 $ 10.31 Cancelled (86,424 ) (86,424 ) $ 27.32 $ 10.31 Outstanding at December 31, 2015 1,626,582 1,626,582 $ 34.87 $ 11.94 Granted 256,191 256,191 $ 69.61 $ 20.10 Exercised (393,240 ) (393,240 ) $ 25.79 $ 9.84 Cancelled (23,089 ) (23,089 ) $ 29.74 $ 11.19 Outstanding at December 31, 2016 1,466,444 1,466,444 $ 43.45 $ 13.94 Vested and exercisable at December 31, 2016 651,574 651,574 $ 29.80 $ 10.69
Non Vested Shares Outstanding	Non-vested shares outstanding as at December 31, 2016 are as follows: Options Outstanding Number of Shares Weighted Average Exercise Price Weighted Average Fair Value Non-vested outstanding at December 31, 2015 968,853 $ 42.14 $ 13.69 Granted 256,191 69.61 20.10 Vested (391,918 ) 35.17 12.04 Forfeited (18,256 ) 31.48 11.62 Non-vested outstanding at December 31, 2016 814,870 $ 54.37 $ 16.55
Information Concerning Outstanding and Exercisable Share Options	The following table summarizes information concerning outstanding and exercisable share options as of December 31, 2016: Options Outstanding Options Exercisable Range Exercise Price Number of Shares Weighted Average Remaining Contractual Life Weighted Average Exercise Price Number of Shares Weighted Average Exercise Price $ 15.84 50,000 0.32 $ 15.84 50,000 $ 15.84 $ 16.80 60,000 2.83 $ 16.80 60,000 $ 16.80 $ 17.17 6,000 2.85 $ 17.17 6,000 $ 17.17 $ 20.28 107,588 2.16 $ 20.28 107,588 $ 20.28 $ 20.59 33,000 3.14 $ 20.59 7,200 $ 20.59 $ 22.26 2,160 0.15 $ 22.26 2,160 $ 22.26 $ 22.30 173,642 3.32 $ 22.30 112,061 $ 22.30 $ 23.66 3,520 3.57 $ 23.66 1,910 $ 23.66 $ 24.46 60,816 1.17 $ 24.46 60,816 $ 24.46 $ 26.20 450 1.38 $ 26.20 450 $ 26.20 $ 26.71 4,450 3.69 $ 26.71 3,560 $ 26.71 $ 29.45 3,000 1.32 $ 29.45 3,000 $ 29.45 $ 32.37 165,865 4.33 $ 32.37 95,457 $ 32.37 $ 36.22 20,178 4.46 $ 36.22 8,443 $ 36.22 $ 37.90 5,720 4.93 $ 37.90 1,600 $ 37.90 $ 40.83 81,658 5.39 $ 40.83 24,646 $ 40.83 $ 47.03 63,813 5.17 $ 47.03 15,693 $ 47.03 $ 48.67 118,493 5.21 $ 48.67 22,992 $ 48.67 $ 51.35 4,030 5.60 $ 51.35 1,612 $ 51.35 $ 65.60 93,534 7.38 $ 65.60 10,557 $ 65.60 $ 66.47 11,931 6.39 $ 66.47 1,417 $ 66.47 $ 66.97 3,118 6.45 $ 66.97 623 $ 66.97 $ 68.39 231,687 6.18 $ 68.39 53,789 $ 68.39 $ 71.95 161,791 7.17 $ 71.95 - $ 71.95 $ 15.84 - $71.95 1,466,444 4.67 $ 43.45 651,574 $ 29.80
Weighted Average Fair Values and Assumptions Used	The weighted average fair values and assumptions were as follows: Year Ended December 31, December 31, December 31, 2016 2015 2014 Weighted average fair value $ 20.10 $ 19.75 $ 14.09 Assumptions: Expected volatility 30 % 30 % 32 % Dividend yield 0 % 0 % 0 % Risk-free interest rate 1.39 % 1.58 % 1.57 % Expected life 5.0 years 5.0 years 5.0 years
RSU and PSU Activity	The following table summarizes RSU and PSU activity for the year ended December 31, 2016: PSU Outstanding Number of Shares PSU Weighted Average Fair Value PSU Weighted Average Remaining Contractual Life RSU Outstanding Number of Shares RSU Weighted Average Fair Value RSU Weighted Average Remaining Contractual Life Outstanding at December 31, 2015 901,773 $ 48.33 1.22 1,067,613 $ 48.30 1.48 Granted 247,992 $ 71.58 391,196 $ 67.45 Shares vested (311,492 ) $ 33.09 (300,019 ) $ 36.13 Forfeited (7,750 ) $ 56.58 (133,306 ) $ 52.36 Outstanding at December 31, 2016 830,523 $ 60.73 1.11 1,025,484 $ 58.64 1.4 0
Schedule of Non-cash Stock Compensation Expense	Non-cash stock compensation expense has been allocated as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Direct costs $ 21,903 $ 18,358 $ 12,531 Selling, general and administrative $ 18,440 $ 14,959 $ 10,211 Total compensation costs $ 40,343 $ 33,317 $ 22,742

Government Grants (Tables)

Government Grants (Tables)	12 Months Ended
	Dec. 31, 2016
Government Grant	December 31, December 31, 2016 2015 (in thousands) Received $ 3,539 $ 3,539 Less accumulated amortization (2,701 ) (2,657 ) Foreign exchange translation adjustment 103 120 Total government grants 941 1,002 Less current portion (54 ) (43 ) Non-current government grants $ 887 $ 959

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2016
Components of Income Before Provision for Income Taxes	The components of income before provision for income taxes are as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Ireland $ 201,221 $ 184,643 $ 143,889 United States 11,466 15,436 6,966 Other 87,485 78,771 51,861 Income before provision for income taxes $ 300,172 $ 278,850 $ 202,716
Components of Provision for Income Taxes	The components of provision for income taxes are as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Provision for income taxes: Current tax expense: Ireland $ 22,931 $ 21,769 $ 19,562 United States 7,768 684 7,891 Other 5,749 13,701 10,695 Total current tax expense 36,448 36,154 38,148 Deferred tax expense/(benefit): Ireland 1,284 26 (1,178 ) United States 613 2,896 (3,031 ) Other (352 ) 235 (3,691 ) Total deferred tax expense/(benefit) 1,545 3,157 (7,900 ) Provision for income taxes 37,993 39,311 30,248 Impact on shareholders equity and other comprehensive income of the tax consequence of : Excess tax benefit on stock compensation (4,332 ) (1,905 ) (2,404 ) Currency impact on long term funding (396 ) 3,574 178 Total $ 33,265 $ 40,980 $ 28,022
Reconciliation of Consolidated Reported Provision for Income Taxes and Statutory Rate	The Company's consolidated reported provision for income taxes differed from the amount that would result from applying the Irish statutory rate as set forth below; Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Taxes at Irish statutory rate of 12.5% (2015:12.5%; 2014:12.5%) $ 37,522 $ 34,856 $ 25,340 Foreign and other income taxed at higher rates 4,642 4,614 3,152 Research & development tax incentives (907 ) (695 ) (1,810 ) Movement in valuation allowance 1,208 (4,133 ) (1,965 ) Effects of change in tax rates 576 (16 ) 543 Increase/(decrease) in unrecognized tax benefits (1,521 ) 5,085 2,869 Effects of permanent items (4,259 ) (463 ) 2,048 Other 732 63 71 Provision for income taxes $ 37,993 $ 39,311 $ 30,248
Tax Effects of Temporary Differences that Give Rise to Significant Portions of Deferred Tax Assets and Deferred Tax Liabilities	The tax effects of temporary differences that give rise to significant portions of deferred tax assets and deferred tax liabilities are presented below: December 31, December 31, 2016 2015 (in thousands) Deferred tax liabilities: Property, plant and equipment $ 979 $ 1,239 Goodwill 26,617 22,170 Other intangible assets 6,700 5,865 Other 1,441 1,293 Total deferred tax liabilities recognized 35,737 30,567 Deferred tax assets: Operating loss and tax credits carryforwards 22,705 22,186 Property, plant and equipment 3,121 2,487 Accrued expenses and payments on account 28,904 29,473 Stock compensation 13,062 12,959 Deferred compensation expense 3,327 2,174 Other 15 566 Total deferred tax assets 71,134 69,845 Valuation allowance for deferred tax assets (20,337 ) (17,184 ) Deferred tax assets recognized 50,797 52,661 Overall net deferred tax asset $ 15,060 $ 22,094
Expected Expiry Dates of NOL's	The expected expiry dates of these losses are as follows: Federal State NOL's NOL's (in thousands) 2017-2018 226 - 2021-2034 34,735 29,049 2035-2036 15,626 21,119 $ 50,587 $ 50,168
Reconciliation of Beginning and Ending Amount of Total Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of total unrecognized tax benefits is as follows: December 31, December 31, December 31, 2016 2015 2014 (in thousands) Unrecognized tax benefits at start of year $ 28,166 $ 23,201 $ 5,780 Increase related to acquired tax positions - 778 14,552 Increase related to prior year tax positions 1,151 1,482 565 Decrease related to prior year tax positions (2,483 ) (315 ) (183 ) Increase related to current year tax positions 1,104 3,063 3,709 Settlements (837 ) - (2 ) Lapse of statute of limitations (481 ) (43 ) (1,220 ) Unrecognized tax benefits at end of year $ 26,620 $ 28,166 $ 23,201

Restructuring and other items (

Restructuring and other items (Tables)	12 Months Ended
	Dec. 31, 2016
Recognized Restructuring and Other Items, Net	Restructuring and other items recognized during the year ended December 31, 2016 comprise: Year Ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Restructuring charges $ 8,159 - $ 8,796 Net charge $ 8,159 - $ 8,796
Restructuring Charges	Workforce Onerous reductions Lease Total (in thousands) Total provision recognized $ 6,190 $ 1,969 $ 8,159 Utilized (5,734 ) (571 ) (6,305 ) Foreign exchange (63 ) - (63 ) Provision at December 31, 2016 $ 393 $ 1,398 $ 1,791 Onerous Asset Lease Impairment Total (in thousands) Total provision recognized $ 3,167 $ 5,629 $ 8,796 Asset write-off - (5,629 ) (5,629 ) Provision at December 31, 2014 $ 3,167 - $ 3,167 Utilized (1,167 ) - (1,167 ) Provision at December 31, 2015 2,000 - 2,000 Utilized (1,359 ) - (1,359 ) Provision at December 31, 2016 641 - 641

Provision for Doubtful Debts (T

Provision for Doubtful Debts (Tables)	12 Months Ended
	Dec. 31, 2016
Provision for Doubtful Debts	The Company does business with most major international pharmaceutical companies. Provision for doubtful debts at December 31, 2016 comprises: December 31, December 31, 2016 2015 (in thousands) Opening provision $ 10,383 $ 5,458 Amounts used during the year (3,782 ) (161 ) Amounts provided during the year 4,651 7,572 Amounts released during the year (1,814 ) (2,244 ) Translation 12 (242 ) Closing provision $ 9,450 $ 10,383

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2016
Future Minimum Rental Commitments for Operating Leases with Non-cancelable Terms	Future minimum rental commitments for operating leases with non-cancelable terms in excess of one year are as follows: Minimum rental payments (in thousands) 2017 34,682 2018 28,219 2019 21,358 2020 15,646 2021 12,477 Thereafter 40,132 Total $ 152,514

Business Segment and Geograph45

Business Segment and Geographical Information (Tables)	12 Months Ended
	Dec. 31, 2016
Distribution of Net Revenue by Geographical Area	a) The distribution of net revenue by geographical area was as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Ireland $ 410,572 $ 429,631 $ 360,376 Rest of Europe 313,185 330,487 372,634 U.S. 763,821 650,941 605,815 Other 178,909 163,919 164,491 Total $ 1,666,487 $ 1,574,978 $ 1,503,316
Distribution of Income from Operations by Geographical Area	b) The distribution of income from operations, including restructuring and other items, by geographical area was as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Ireland $ 216,149 $ 189,035 $ 138,185 Rest of Europe 34,200 38,166 14,481 U.S. 41,348 45,320 39,058 Other 19,997 9,015 10,626 Total $ 311,694 $ 281,536 $ 202,350 c) The distribution of income from operations, excluding restructuring and other items, by geographical area was as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Ireland $ 218,334 $ 189,035 $ 138,185 Rest of Europe 36,509 38,166 23,277 U.S. 44,590 45,320 39,058 Other 20,420 9,015 10,626 Total $ 319,853 $ 281,536 $ 211,146
Distribution of Property, Plant and Equipment, Net, by Geographical Area	d) The distribution of property, plant and equipment, net, by geographical area was as follows: December 31, December 31, 2016 2015 (in thousands) Ireland $ 105,684 $ 101,736 Rest of Europe 6,231 7,334 U.S. 29,428 34,520 Other 7,624 6,628 Total $ 148,967 $ 150,218
Distribution of Depreciation and Amortization by Geographical Area	e) The distribution of depreciation and amortization by geographical area was as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Ireland $ 25,766 $ 22,100 $ 20,731 Rest of Europe 6,914 11,055 7,478 U.S. 23,462 20,106 20,491 Other 3,433 4,416 3,842 Total $ 59,575 $ 57,677 $ 52,542
Distribution of Total Assets by Geographical Area	f) The distribution of total assets by geographical area was as follows: December 31, December 31, 2016 2015 * (in thousands) Ireland $ 766,120 $ 663,060 Rest of Europe 337,062 343,733 U.S. 651,160 641,769 Other 71,501 68,647 Total $ 1,825,843 $ 1,717,209 * The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs.
Distribution of Capital Expenditures by Geographical Area	g) The distribution of capital expenditures by geographical area was as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Ireland $ 27,670 $ 30,900 $ 15,117 Rest of Europe 2,851 1,916 2,278 U.S. 8,432 15,256 12,224 Other 3,648 1,658 3,160 Total $ 42,601 $ 49,730 $ 32,779
Clients Representing Company's Net Revenue	h) The following table sets forth the clients which represented 10% or more of the Company's net revenue in each of the periods set out below. Year ended December 31, December 31, December 31, 2016 2015 2014 Client A 26 % 31 % 31 %
Distribution of Interest Income by Business Segment	i) The distribution of interest income by geographical area was as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Ireland $ 407 $ 102 $ 284 Rest of Europe 1,040 1,151 798 U.S. 2 4 - Other 35 49 69 Total $ 1,484 $ 1,306 $ 1,151
Distribution of Tax Charge by Geographical Area	j) The distribution of the income tax charge by geographical area was as follows: Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Ireland $ 24,215 $ 21,795 $ 18,384 Rest of Europe 5,528 8,007 2,855 U.S. 8,381 3,580 4,860 Other (131 ) 5,929 4,149 Total $ 37,993 $ 39,311 $ 30,248

Supplemental Disclosure of Ca46

Supplemental Disclosure of Cash Flow Information (Tables)	12 Months Ended
	Dec. 31, 2016
Supplemental Disclosure of Cash Flow Information	Year ended December 31, December 31, December 31, 2016 2015 2014 (in thousands) Cash paid for interest $ 13,615 $ 2,175 $ 533 Cash paid for income taxes $ 10,205 $ 14,829 $ 17,829

Accumulated Other Comprehensi47

Accumulated Other Comprehensive Income (Tables)	12 Months Ended
	Dec. 31, 2016
Accumulated Other Comprehensive Income	December 31, December 31, 2016 2015 (in thousands) Currency translation adjustments $ (70,154 ) $ (57,315 ) Currency impact on long term funding (Net of tax) (13,912 ) (5,484 ) Actuarial loss on defined benefit pension plan (note 9) (5,905 ) (3,420 ) Unrealized capital gain/(loss) – investments (note 3) (23 ) (34 ) Net realized gain on interest rate hedge 3,694 4,617 Total $ (86,300 ) $ (61,636 )

Description of Business - Addit

Description of Business - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2016EmployeeCountryLocation
Product Information [Line Items]
Number of employees | Employee	12,500
Number of locations in which company operates | Location	87
Number of countries in which company operates | Country	38
Geographic Concentration Risk | United States | Sales Revenue, Net
Product Information [Line Items]
Percentage of company revenue	45.80%
Geographic Concentration Risk | Europe | Sales Revenue, Net
Product Information [Line Items]
Percentage of company revenue	43.40%
Geographic Concentration Risk | Rest of World | Sales Revenue, Net
Product Information [Line Items]
Percentage of company revenue	10.80%

Significant Accounting Polici49

Significant Accounting Policies - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Significant Accounting Policies [Line Items]
Advertising and promotion costs	$ 7,167,050	$ 4,513,750	$ 3,563,900
Impairment charge	0	0	$ 0
Carrying value of inventory	$ 2,400,000	1,800,000
Cash proceeds from interest rate hedge		$ 4,658,000
Senior Notes
Significant Accounting Policies [Line Items]
Debt instrument, interest rate		3.64%
Debt instrument, term		5 years
Cash proceeds from interest rate hedge		$ 4,658,000
Interest rate hedge, inception date	Oct. 5, 2015
Interest rate hedge, maturity date	Nov. 17, 2015

Adjustments Resulting from Fore

Adjustments Resulting from Foreign Currency Translation (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Intercompany Foreign Currency Balance [Line Items]
Amounts charged/(credited)	$ 2,094	$ (3,608)	$ (5,942)

Estimated Useful Lives of Asset

Estimated Useful Lives of Assets (Detail)	12 Months Ended
	Dec. 31, 2016
Building
Property, Plant and Equipment [Line Items]
Estimated useful lives	40 years
Office furniture and fixtures
Property, Plant and Equipment [Line Items]
Estimated useful lives	8 years
Laboratory equipment
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Motor vehicles
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Computer equipment and software | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	2 years
Computer equipment and software | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	8 years

Reconciliation of Number of Sha

Reconciliation of Number of Shares Used in Computation of Basic and Diluted Net Income Per Ordinary Share (Detail) - shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Weighted Average Number of Diluted Shares Outstanding [Line Items]
Weighted average number of ordinary shares outstanding for basic net income per ordinary share	55,248,900	58,746,935	61,496,115
Effect of dilutive share options outstanding	1,158,236	1,543,098	1,635,302
Weighted average number of ordinary shares outstanding for diluted net income per ordinary share	56,407,136	60,290,033	63,131,417

Cost and Fair Value of Investme

Cost and Fair Value of Investments (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016		Dec. 31, 2015		Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
At start of year	$ 85,990	[1]	$ 97,100
Purchases	22,030		14,194
Sales and maturities	(40,858)		(25,708)
Interest on short term investments	823		571		$ 910
Realized gain/(loss) on sale of short term investments	50		(113)
Unrealized capital gain/(loss) - investments	11		(54)
At end of year	$ 68,046		$ 85,990	[1]	$ 97,100
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).

Short Team Investments - Availa

Short Team Investments - Available for Sale - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Short term investments average maturity period	1 year 4 months 13 days	1 year 4 months 6 days

Available For Sale Short Term I

Available For Sale Short Term Investments by Major Security Type (Detail) $ in Thousands	Dec. 31, 2016USD ($)
Schedule of Available-for-sale Securities [Line Items]
Cost Total	$ 68,070
Unrealized gains / (losses)	(20)
Fair Value Total	68,050
Maturity by period, less than 1 year	29,190
Maturity by period, 1 to 5 years	38,860
Us Government Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Cost Total	13,980
Unrealized gains / (losses)	(40)
Fair Value Total	13,940
Maturity by period, less than 1 year	3,000
Maturity by period, 1 to 5 years	10,940
Corporate Securities
Schedule of Available-for-sale Securities [Line Items]
Cost Total	52,980
Unrealized gains / (losses)	20
Fair Value Total	53,000
Maturity by period, less than 1 year	25,080
Maturity by period, 1 to 5 years	27,920
Term Deposits
Schedule of Available-for-sale Securities [Line Items]
Cost Total	1,110
Fair Value Total	1,110
Maturity by period, less than 1 year	$ 1,110

Goodwill (Detail)

Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016		Dec. 31, 2015
Goodwill [Line Items]
Opening goodwill	$ 588,434	[1]	$ 463,324
Current year acquisitions (note 4 (a))	34,576		133,123
Prior period acquisition (note 4(b))	7,689		4,418
Foreign exchange movement	(14,611)		(12,431)
Closing goodwill	$ 616,088		$ 588,434	[1]
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).

Goodwill - Additional Informati

Goodwill - Additional Information (Detail) $ in Thousands		Sep. 15, 2016USD ($)		Dec. 04, 2015USD ($)PatientSite	Mar. 25, 2015USD ($)	Feb. 27, 2015USD ($)	May 07, 2014USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	[1]	Dec. 31, 2014USD ($)
Business Acquisition [Line Items]
Goodwill								$ 616,088	$ 588,434		$ 463,324
Clinical Research Management Inc.
Business Acquisition [Line Items]
Goodwill		$ 34,576	[2]					34,576
Net cash outflow		52,400
Other liabilities assumed		9,200
Maximum additional consideration that might be payable		12,000
Fair Value of the deferred consideration on acquisition		6,000
Cash consideration		$ 52,396
PMG
Business Acquisition [Line Items]
Goodwill	[3]			$ 48,728
Other liabilities assumed				10,060
Cash consideration				$ 53,681				$ 1,613
Number of clinical research sites acquired | Site				48
Working capital adjustment				$ 1,613
PMG | Minimum
Business Acquisition [Line Items]
Number of active patients via electronic medical records acquired | Patient				2,000,000
MediMedia Pharma Solutions
Business Acquisition [Line Items]
Goodwill	[4]					$ 92,084
Net cash outflow						116,002
Other liabilities assumed	[5]					11,283
Cash consideration						108,717
Cash consideration, net of working capital adjustment						104,719
Working capital adjustment						$ 3,998
Aptiv Solutions
Business Acquisition [Line Items]
Goodwill	[6]						$ 125,627
Cash consideration							143,500
Working capital adjustment					$ 1,964		$ 1,964
Percentage of common stock acquired							100.00%
Adjustments to cash consideration	[7]						$ 22,399
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).
[2]	Goodwill represents the acquisition of an established workforce with experience in preclinical through Phase IV support of clinical research and clinical trial services for biologics, drugs and devices. Goodwill related to the US portion of the business acquired is tax deductible.
[3]	Goodwill represents the acquisition of an established workforce with experience in clinical trial consulting and regulatory support for the development of drugs, medical devices and diagnostics, with a specific focus on strategy to increase efficiency and productivity in product development. In finalizing the goodwill on acquisition of PMG in the twelve month period from acquisition, fair value adjustments were made to deferred tax liabilities ($3.1 million), accounts receivable acquired ($1.4 million), other liabilities ($1.2 million) and the value of the customer list and order backlog assets acquired ($0.4 million). Additional consideration of $1.6 million was provided on completion of the contractual working capital process.
[4]	Goodwill represents the acquisition of an established workforce with experience in the provision of strategic payer-validated market access solutions while the acquisition of Complete Healthcare Communications comprises an established workforce with significant communication experience working with medical affairs, commercial and brand development teams within the life science industry. Goodwill related to the US portion of the business acquired is tax deductible.
[5]	Payments made at acquisition date of $11.3 million were in respect of certain one-time liabilities at the acquisition date which have subsequently been discharged.
[6]	Goodwill represents the acquisition of an established workforce with experience in clinical trial consulting and regulatory support for the development of drugs, medical devices and diagnostics, with a specific focus on strategy to increase efficiency and productivity in product development. Goodwill related to the US portion of the business acquired is tax deductible.
[7]	Adjustments to cash consideration represent certain one-time liabilities (including loan notes) identified at the acquisition date which have subsequently been paid.

Summary of Estimates of Fair Va

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed of Clinical Research Management, Inc. (Detail) - USD ($) $ in Thousands		Sep. 15, 2016		Dec. 31, 2016	Dec. 31, 2015	[1]	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill				$ 616,088	$ 588,434		$ 463,324
Clinical Research Management Inc.
Business Acquisition [Line Items]
Cash		$ 3,168
Property, plant and equipment		939
Goodwill		34,576	[2]	$ 34,576
Intangible assets	[3]	8,644
Accounts receivable		11,725
Unbilled revenue		2,814
Prepayments and other current assets		1,673
Accounts payable		(621)
Other liabilities		(4,515)
Non-current other liabilities		(7)
Net assets acquired		58,396
Cash consideration		52,396
Contingent consideration		$ 6,000
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).
[2]	Goodwill represents the acquisition of an established workforce with experience in preclinical through Phase IV support of clinical research and clinical trial services for biologics, drugs and devices. Goodwill related to the US portion of the business acquired is tax deductible.
[3]	The Company has made an initial estimate of separate intangible assets (comprised of customer relationships and order book) acquired of $8.6 million. This assessment is under review and will be finalized within 12 months of the date of acquisition

Summary of Estimates of Fair 59

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed of Clinical Research Management, Inc. (Parenthetical) (Detail) $ in Thousands	Sep. 15, 2016USD ($)
Clinical Research Management Inc.
Business Acquisition [Line Items]
Intangible asset	$ 8,644	[1]
[1]	The Company has made an initial estimate of separate intangible assets (comprised of customer relationships and order book) acquired of $8.6 million. This assessment is under review and will be finalized within 12 months of the date of acquisition

Proforma Effect in Net Revenue,

Proforma Effect in Net Revenue, Net Income and Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Clinical Research Management Inc.
Business Acquisition [Line Items]
Net revenue	$ 1,713,245	$ 1,639,085
Net income	$ 266,148	$ 244,167
Basic earnings per share	$ 4.82	$ 4.16
Diluted earnings per share	$ 4.72	$ 4.05
PMG
Business Acquisition [Line Items]
Net revenue		$ 1,601,891	$ 1,527,685
Net income		$ 243,004	$ 172,390
Basic earnings per share		$ 4.14	$ 2.80
Diluted earnings per share		$ 4.03	$ 2.73
MediMedia Pharma Solutions
Business Acquisition [Line Items]
Net revenue		$ 1,581,816	$ 1,556,936
Net income		$ 239,361	$ 179,289
Basic earnings per share		$ 4.07	$ 2.92
Diluted earnings per share		$ 3.97	$ 2.84
Aptiv Solutions
Business Acquisition [Line Items]
Net revenue			$ 1,543,820	$ 1,451,682
Net income			$ 172,508	$ 101,857
Basic earnings per share			$ 2.81	$ 1.67
Diluted earnings per share			$ 2.73	$ 1.64

Summary of Estimates of Fair 61

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed of PMG (Detail) - USD ($) $ in Thousands		Dec. 04, 2015	Dec. 31, 2016	Dec. 31, 2015		Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill			$ 616,088	$ 588,434	[1]	$ 463,324
Total cash outflows			54,209	$ 166,292		$ 124,301
PMG
Business Acquisition [Line Items]
Cash		$ 194
Property, plant and equipment		712
Goodwill	[2]	48,728
Accounts receivable		11,597
Prepayments and other current assets		1,329
Accounts payable		(530)
Other liabilities		(3,456)
Non-current deferred tax liability		(3,106)
Net assets acquired		65,354
Cash consideration		53,681	$ 1,613
Other liabilities assumed		10,060
Working capital adjustment		1,613
Total cash outflows		65,354
PMG | Customer Lists
Business Acquisition [Line Items]
Intangible assets		6,938
PMG | Order Backlog
Business Acquisition [Line Items]
Intangible assets		$ 2,948
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).
[2]	Goodwill represents the acquisition of an established workforce with experience in clinical trial consulting and regulatory support for the development of drugs, medical devices and diagnostics, with a specific focus on strategy to increase efficiency and productivity in product development. In finalizing the goodwill on acquisition of PMG in the twelve month period from acquisition, fair value adjustments were made to deferred tax liabilities ($3.1 million), accounts receivable acquired ($1.4 million), other liabilities ($1.2 million) and the value of the customer list and order backlog assets acquired ($0.4 million). Additional consideration of $1.6 million was provided on completion of the contractual working capital process.

Summary of Estimates of Fair 62

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed of PMG (Parenthetical) (Detail) - PMG - USD ($) $ in Thousands	Dec. 04, 2015	Dec. 31, 2016
Business Acquisition [Line Items]
Fair value adjustment to deferred tax liability		$ 3,100
Fair value adjustment to accounts receivable		1,400
Fair value adjustment to other liabilities		1,200
Cash consideration	$ 53,681	1,613
Customer list and order backlog
Business Acquisition [Line Items]
Fair value adjustment to intangible assets		$ 400

Summary of Estimates of Fair 63

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed of MediMedia Pharma Solutions (Detail) - USD ($) $ in Thousands		Feb. 27, 2015	Dec. 31, 2016	Dec. 31, 2015	[1]	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill			$ 616,088	$ 588,434		$ 463,324
MediMedia Pharma Solutions
Business Acquisition [Line Items]
Property, plant and equipment		$ 1,049
Goodwill	[2]	92,084
Accounts receivable		5,240
Unbilled revenue		4,324
Prepayments and other current assets		621
Accounts payable		(749)
Payments on account		(4,186)
Deferred tax liability		(2,171)
Other liabilities		(5,483)
Net assets acquired		116,002
Cash consideration		108,717
Other liabilities assumed	[3]	11,283
Gross cash outflows		120,000
Working capital adjustment		(3,998)
Net cash outflows		116,002
MediMedia Pharma Solutions | Customer Lists
Business Acquisition [Line Items]
Intangible asset		22,752
MediMedia Pharma Solutions | Order Backlog
Business Acquisition [Line Items]
Intangible asset		$ 2,521
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).
[2]	Goodwill represents the acquisition of an established workforce with experience in the provision of strategic payer-validated market access solutions while the acquisition of Complete Healthcare Communications comprises an established workforce with significant communication experience working with medical affairs, commercial and brand development teams within the life science industry. Goodwill related to the US portion of the business acquired is tax deductible.
[3]	Payments made at acquisition date of $11.3 million were in respect of certain one-time liabilities at the acquisition date which have subsequently been discharged.

Summary of Estimates of Fair 64

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed of MediMedia Pharma Solutions (Parenthetical) (Detail) $ in Thousands	Feb. 27, 2015USD ($)
MediMedia Pharma Solutions
Business Acquisition [Line Items]
Other liabilities assumed	$ 11,283	[1]
[1]	Payments made at acquisition date of $11.3 million were in respect of certain one-time liabilities at the acquisition date which have subsequently been discharged.

Summary of Estimates of Fair 65

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed of Aptiv Solutions (Detail) - USD ($) $ in Thousands		Mar. 25, 2015	May 07, 2014	Dec. 31, 2016	Dec. 31, 2015	[1]	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill				$ 616,088	$ 588,434		$ 463,324
Aptiv Solutions
Business Acquisition [Line Items]
Property, plant and equipment			$ 6,924
Goodwill	[2]		125,627
Cash and cash equivalents			3,484
Accounts receivable			25,091
Unbilled revenue			21,154
Prepayments and other current assets			4,180
Non-current assets			2,911
Accounts payable			(9,565)
Other liabilities			(29,782)
Payments on account			(31,094)
Non-current other liabilities			(11,303)
Loan notes payable	[3]		(17,790)
Net assets acquired			119,137
Cash consideration			143,500
Working capital adjustment		$ (1,964)	(1,964)
Gross cash outflows			141,536
Adjustments to cash consideration	[3]		(22,399)
Net assets acquired/Net purchase consideration			119,137
Aptiv Solutions | Customer Relationships
Business Acquisition [Line Items]
Intangible asset			21,400
Aptiv Solutions | Order Backlog
Business Acquisition [Line Items]
Intangible asset			$ 7,900
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).
[2]	Goodwill represents the acquisition of an established workforce with experience in clinical trial consulting and regulatory support for the development of drugs, medical devices and diagnostics, with a specific focus on strategy to increase efficiency and productivity in product development. Goodwill related to the US portion of the business acquired is tax deductible.
[3]	Adjustments to cash consideration represent certain one-time liabilities (including loan notes) identified at the acquisition date which have subsequently been paid.

Intangible Assets (Detail)

Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Cost
Foreign exchange movement	$ (6,578)	$ (5,092)
Intangible assets gross	120,164	113,381
Accumulated amortization	(67,037)	(49,587)
Foreign exchange movement	3,483	2,333
Net book value	56,610	66,127	[1]
Customer Relationships
Cost
Intangible assets gross	87,218	90,541
Technology Assets
Cost
Intangible assets gross	11,169	11,169
Order Backlog
Cost
Intangible assets gross	16,540	13,592
Trade Names
Cost
Intangible assets gross	1,357	1,357
Volunteer List Acquired
Cost
Intangible assets gross	1,325	1,325
Non-compete Agreements
Cost
Intangible assets gross	489	$ 489
ClinicalRM Intangible Asset
Cost
Intangible assets gross	$ 8,644
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).

Intangible Assets - Additional

Intangible Assets - Additional Information (Detail) $ in Thousands

Sep. 15, 2016USD ($)

Dec. 04, 2015USD ($)Site

Feb. 27, 2015USD ($)

May 07, 2014USD ($)

Feb. 15, 2013USD ($)

Feb. 28, 2012USD ($)

Feb. 15, 2012USD ($)

Jul. 14, 2011USD ($)

Jan. 14, 2011USD ($)

Nov. 14, 2008USD ($)

Feb. 11, 2008USD ($)

Dec. 31, 2016USD ($)

Dec. 31, 2015USD ($)

Indefinite-lived Intangible Assets [Line Items]

Amount amortized since date of acquisition

$ 67,037

$ 49,587

PMG

Indefinite-lived Intangible Assets [Line Items]

Amount amortized since date of acquisition

2,700

Number of clinical research sites acquired | Site

48

PMG | Customer Relationships

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 6,900

Amortization period

7 years

PMG | Order Backlog

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 3,000

Amortization period

2 years

MediMedia Pharma Solutions

Indefinite-lived Intangible Assets [Line Items]

Amount amortized since date of acquisition

8,500

MediMedia Pharma Solutions | Customer Relationships

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 22,800

Amortization period

7 years

MediMedia Pharma Solutions | Order Backlog

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 2,500

Amortization period

1 year

Aptiv Solutions

Indefinite-lived Intangible Assets [Line Items]

Amount amortized since date of acquisition

15,200

Aptiv Solutions | Customer Relationships

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 21,400

Amortization period

7 years

Aptiv Solutions | Order Backlog

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 7,900

Amortization period

3 years

Clinical Trial Services of Cross Country Healthcare Inc.

Indefinite-lived Intangible Assets [Line Items]

Amount amortized since date of acquisition

3,900

Clinical Trial Services of Cross Country Healthcare Inc. | Customer Relationships

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 3,300

Amortization period

3 years

Clinical Trial Services of Cross Country Healthcare Inc. | Order Backlog

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 600

Amortization period

1 year

PriceSpective

Indefinite-lived Intangible Assets [Line Items]

Amount amortized since date of acquisition

5,700

PriceSpective | Customer Relationships

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 10,200

Amortization period

10 years

PriceSpective | Order Backlog

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 400

Amortization period

9 months 18 days

PriceSpective | Non-compete Agreements

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 400

Amortization period

3 years

BeijingWits Medical

Indefinite-lived Intangible Assets [Line Items]

Amount amortized since date of acquisition

1,300

BeijingWits Medical | Customer Relationships

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 1,800

Amortization period

10 years

BeijingWits Medical | Order Backlog

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 400

Amortization period

4 years

BeijingWits Medical | Non-compete Agreements

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 10

Amortization period

5 years

Firecrest Clinical Limited

Indefinite-lived Intangible Assets [Line Items]

Amount amortized since date of acquisition

12,800

Firecrest Clinical Limited | Customer Relationships

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 5,200

Amortization period

7 years 6 months

Firecrest Clinical Limited | Order Backlog

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 1,200

Amortization period

1 year 2 months 12 days

Firecrest Clinical Limited | Technology Assets

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 11,200

Amortization period

7 years 6 months

Firecrest Clinical Limited | Trade Names

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 1,400

Amortization period

4 years 6 months

Oxford Outcomes Limited

Indefinite-lived Intangible Assets [Line Items]

Amount amortized since date of acquisition

6,700

Oxford Outcomes Limited | Customer Relationships

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 6,600

Amortization period

6 years 6 months

Oxford Outcomes Limited | Order Backlog

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 600

Amortization period

2 years

Prevalere Life Sciences

Indefinite-lived Intangible Assets [Line Items]

Amount amortized since date of acquisition

6,400

Prevalere Life Sciences | Customer Lists

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 7,400

Prevalere Life Sciences | Minimum | Customer Lists

Indefinite-lived Intangible Assets [Line Items]

Amortization period

7 years

Prevalere Life Sciences | Maximum | Customer Lists

Indefinite-lived Intangible Assets [Line Items]

Amortization period

11 years

Healthcare Discoveries

Indefinite-lived Intangible Assets [Line Items]

Amount amortized since date of acquisition

2,900

Healthcare Discoveries | Customer Relationships

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 1,600

Healthcare Discoveries | Volunteer List Acquired

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 1,300

Healthcare Discoveries | Minimum | Customer Relationships

Indefinite-lived Intangible Assets [Line Items]

Amortization period

2 years

Healthcare Discoveries | Minimum | Volunteer List Acquired

Indefinite-lived Intangible Assets [Line Items]

Amortization period

6 years

Healthcare Discoveries | Maximum | Customer Relationships

Indefinite-lived Intangible Assets [Line Items]

Amortization period

9 years

Clinical Research Management Inc.

Indefinite-lived Intangible Assets [Line Items]

Value of amortizable intangible asset acquired

$ 8,600

Amortization period

6 years

Amount amortized since date of acquisition

$ 900

Future Intangible Asset Amortiz

Future Intangible Asset Amortization Expense (Detail) $ in Thousands	Dec. 31, 2016USD ($)
Finite-Lived Intangible Assets [Line Items]
2,017	$ 15,449
2,018	11,815
2,019	9,921
2,020	9,634
2,021	7,597
Finite Lived Intangible Assets, Amortization Expense, Net, Total	$ 54,416

Property, Plant and Equipment69

Property, Plant and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Cost
Land	$ 3,464	$ 3,464
Building	77,950	80,861
Computer equipment and software	315,984	282,909
Office furniture and fixtures	70,218	65,152
Laboratory equipment	31,487	31,098
Leasehold improvements	20,933	20,647
Motor vehicles	43	47
Property, Plant and Equipment, Gross, Total	520,079	484,178
Less accumulated depreciation and asset write offs	(371,112)	(333,960)
Property, plant and equipment (net)	$ 148,967	$ 150,218	[1]
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).

Other Liabilities (Detail)

Other Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Other Liabilities [Line Items]
Personnel related liabilities	$ 135,349	$ 159,339
Facility related liabilities	14,182	22,517
General overhead liabilities	31,126	29,257
Other liabilities	7,584	18,607
Short term government grants (note 11)	54	43
Restructuring and other items (note 14)	2,432	2,116
Other liabilities (Note 7)	$ 190,727	$ 231,879	[1]
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).

Other Non-Current Liabilities71

Other Non-Current Liabilities (Detail) - USD ($) $ in Thousands		Dec. 31, 2016	Dec. 31, 2015
Schedule of Accrued Liabilities [Line Items]
Defined benefit pension obligations, net (note 9)		$ 8,952	$ 7,189
Other non-current liabilities	[1]	14,800	5,035
Non-current other liabilities		$ 23,752	$ 12,224	[2]
[1]	*An amount of $6.0 million is included within other non-current liabilities in respect of contingent consideration for the acquisition of ClinicalRM. See note 4 (a).
[2]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).

Other Non-Current Liabilities72

Other Non-Current Liabilities (Parenthetical) (Detail) $ in Millions	Sep. 15, 2016USD ($)
Clinical Research Management Inc.
Schedule of Accrued Liabilities [Line Items]
Contingent consideration	$ 6

Employee Benefits - Additional

Employee Benefits - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	May 07, 2014
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan description	Certain Company employees are eligible to participate in a defined contribution plan (the "Plan"). Participants in the Plan may elect to defer a portion of their pre-tax earnings into a pension plan, which is run by an independent party. The Company matches participant's contributions typically at 6% of the participant's annual compensation.
Aptiv Solutions
Defined Benefit Plan Disclosure [Line Items]
Percentage of common stock acquired				100.00%
Defined Benefit Plan Contributions
Defined Benefit Plan Disclosure [Line Items]
Contributions percentage of annual compensation	6.00%
Employer contributions	$ 20,952	$ 20,439	$ 22,370
Defined Contribution Pension Plan 401(k)
Defined Benefit Plan Disclosure [Line Items]
Participant's contributions percentage matches	50.00%
Participant's contributions percentage of annual compensation	6.00%
Deferred salary arrangement employer contribution	$ 15,223	$ 12,802	$ 10,514
Foreign Postretirement Benefit Plan | UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Net loss for defined benefit pension plan that will be amortized from accumulated other comprehensive income into net periodic benefit cost over the next year	(200)
Net prior service cost for defined benefit pension plan that will be amortized from accumulated other comprehensive income into net periodic benefit cost over the next year	$ 0
Expected long-term rate of return after application of a market value reduction factor	2.10%
Expected long term rate of return on bonds Description	Applying the above expected long term rates of return to the asset distribution at December 31, 2016, gives rise to an expected overall rate of return of scheme assets of approximately 2.1% per annum.
Contribution to pension fund in the year ending December 31, 2017	$ 100
Expected benefit cash flow description	The expected cash flows are estimated figures based on the members expected to retire over the next 10 years assuming no early retirements plus an additional amount based on recent average withdrawal experience.
Retirement period used as a basis to estimate expected cash flows	10 years
Foreign Postretirement Benefit Plan | UNITED KINGDOM | iboxx Corporate Bonds
Defined Benefit Plan Disclosure [Line Items]
Basis point increase in benefits obligation discount rate	0.10%
Defined benefit plan bond maturity period	15 years
Foreign Postretirement Benefit Plan | UNITED KINGDOM | Gilts
Defined Benefit Plan Disclosure [Line Items]
Percentage of investments	75.00%
Foreign Postretirement Benefit Plan | UNITED KINGDOM | Corporate Bond Securities
Defined Benefit Plan Disclosure [Line Items]
Percentage of investments	25.00%
Foreign Postretirement Benefit Plan | UNITED KINGDOM | Legal and General over 15 year Gilts Index
Defined Benefit Plan Disclosure [Line Items]
Expected long term rate of return on bonds Description	The long-term expected return on corporate bonds and gilts (fixed interest and index linked) is determined by reference to bond yields and gilt yields at the balance sheet date.
Foreign Postretirement Benefit Plan | SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Net loss for defined benefit pension plan that will be amortized from accumulated other comprehensive income into net periodic benefit cost over the next year	$ (41)
Net prior service cost for defined benefit pension plan that will be amortized from accumulated other comprehensive income into net periodic benefit cost over the next year	8
Foreign Pension Plan | SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Contribution to pension fund in the year ending December 31, 2017	$ 200
Foreign Pension Plan | SWITZERLAND | Aptiv Solutions
Defined Benefit Plan Disclosure [Line Items]
Percentage of common stock acquired				100.00%

Change in Benefit Obligations (

Change in Benefit Obligations (Detail) - Foreign Postretirement Benefit Plan - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	$ 27,369	$ 32,875
Service cost	75	78	$ 91
Interest cost	1,017	1,140	1,235
Plan participants' contributions	22	26
Expenses	8		359
Benefits paid	(104)	(1,111)
Actuarial (gain)/loss	10,057	(3,992)
Foreign currency exchange rate changes	(5,538)	(1,647)
Benefit obligation at end of year	32,906	27,369	32,875
SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	8,537	8,884
Service cost	352	618
Interest cost	82	159
Plan participants' contributions	150
Settlement	(909)
Prior service cost	(88)
Transferred balances/(benefits paid)	53	(1,146)
Actuarial (gain)/loss	(1,157)	81
Foreign currency exchange rate changes	(92)	(59)
Benefit obligation at end of year	$ 6,928	$ 8,537	$ 8,884

Change in Plan Assets (Detail)

Change in Plan Assets (Detail) - Foreign Postretirement Benefit Plan - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year	$ 23,367	$ 25,409
Expected return on plan assets	646	661	$ 1,299
Actual return on plan assets	5,861	277
Employer contributions	108	114
Plan participants' contributions	22	26
Benefits paid	(104)	(1,111)
Foreign currency exchange rate changes	(4,378)	(1,348)
Fair value of plan assets at end of year	24,876	23,367	25,409
SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year	5,350	7,061
Expected return on plan assets	48	93
Actual return on plan assets	1,233	(1,075)
Scheme contributions	195	194
Plan participants' contributions	150	216
Transferred balances/(benefits paid)	53	(1,146)
Settlement	(909)
Foreign currency exchange rate changes	(114)	7
Fair value of plan assets at end of year	$ 6,006	$ 5,350	$ 7,061

Funded Status - United Kingdom

Funded Status - United Kingdom (Detail) - Foreign Postretirement Benefit Plan - UNITED KINGDOM - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ (32,906)	$ (27,369)
Fair value of plan assets	24,876	23,367	$ 25,409
Funded status	(8,030)	(4,002)
Non-current other liabilities (note 8)	$ (8,030)	$ (4,002)

Components of Net Periodic Bene

Components of Net Periodic Benefit Cost (Detail) - Foreign Postretirement Benefit Plan - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 75	$ 78	$ 91
Interest cost	1,017	1,140	1,235
Expected return on plan assets	(646)	(661)	(1,299)
Amortization of net loss		224	20
Expenses	8		359
Net periodic benefit cost	454	781	$ 406
SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Service cost	352	618
Interest cost	82	159
Expected return on plan assets	(48)	(93)
Amortization of prior service credit	88
Settlement	(909)
SWITZERLAND | Includes Financial Instruments, Property Occupied by, or Other Assets
Defined Benefit Plan Disclosure [Line Items]
Service cost	352	402
Interest cost	82	159
Expected return on plan assets	(48)	(119)
Amortization of net loss	22
Amortization of prior service credit	(8)
Settlement	(136)
Curtailment loss		18
Net periodic benefit cost	$ 264	$ 460

Net Periodic Pension Benefit Co

Net Periodic Pension Benefit Cost Assumptions (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Total	$ 2,485	$ (2,693)	$ 4,125
Foreign Postretirement Benefit Plan | UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.00%	3.60%	4.70%
Rate of compensation increase	3.70%	3.60%	4.00%
Expected rate of return on plan assets	3.00%	2.70%	6.10%
Actuarial (gain)/loss - benefit obligation	$ 10,057	$ (3,992)	$ 8,270
Actuarial (gain)/loss - plan assets	(5,215)	384	(4,125)
Actuarial gain recognized in net periodic benefit cost		(224)	(20)
Total	$ 4,842	$ (3,832)	$ 4,125
Foreign Postretirement Benefit Plan | SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Discount rate	0.95%	1.35%
Rate of compensation increase	2.00%	2.00%
Expected rate of return on plan assets	0.95%	1.35%
Actuarial (gain)/loss - benefit obligation	$ (1,157)	$ 81
Actuarial (gain)/loss - plan assets	(1,233)	1,075
Prior service credit/(cost) recognized in net periodic benefit cost	136	(17)
Actuarial gain recognized in net periodic benefit cost	(22)
Amortization of net prior service credit	8
Net prior service credit occurring during the year	(89)
Total	$ (2,357)	$ 1,139

Amounts recognized in accumulat

Amounts recognized in accumulated other comprehensive income that have not been recognized (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Total	$ 5,905	$ 3,420
Foreign Postretirement Benefit Plan | UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Net actuarial (gain)/loss	7,123	2,281	$ 6,113
Total	7,123	2,281	$ 6,113
Foreign Postretirement Benefit Plan | SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Net actuarial (gain)/loss	(1,218)	1,139
Total	$ (1,218)	$ 1,139

Assumptions Used in Determining

Assumptions Used in Determining Benefit Obligation (Detail) - Foreign Postretirement Benefit Plan	Dec. 31, 2016	Dec. 31, 2015
UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.70%	4.00%
Rate of compensation increase	3.90%	3.70%
SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Discount rate	0.75%	0.95%
Rate of compensation increase	2.00%	2.00%

Expected Long Term Rates of Ret

Expected Long Term Rates of Return on Different Asset Classes (Detail) - Foreign Postretirement Benefit Plan - UNITED KINGDOM	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Expected long-term return per annum	3.00%	2.70%	6.10%
Corporate Bond Securities
Defined Benefit Plan Disclosure [Line Items]
Expected long-term return per annum	2.70%
Gilts
Defined Benefit Plan Disclosure [Line Items]
Expected long-term return per annum	1.90%

Actual Plan Asset Allocation (D

Actual Plan Asset Allocation (Detail) - UNITED KINGDOM - Foreign Postretirement Benefit Plan	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations	100.00%	100.00%
Corporate Bond Securities
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations	25.00%	26.00%
Gilts
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations	75.00%	74.00%

Plan Asset Fair Value Measureme

Plan Asset Fair Value Measurements (Detail) - Foreign Postretirement Benefit Plan - UNITED KINGDOM - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 24,876	$ 23,367	$ 25,409
Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	24,876	23,367
Fair Value, Inputs, Level 1 | Cash
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	16	3
Fair Value, Inputs, Level 1 | Fixed Income Securities | Legal and General Active Corporate Bond Over - 10 Year
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6,095	6,256
Fair Value, Inputs, Level 1 | Fixed Income Securities | Legal and General Gilt Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6,725	6,528
Fair Value, Inputs, Level 1 | Fixed Income Securities | Legal and General Index Linked Gilt Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 12,040	$ 10,580

Annual Benefit Payments (Detail

Annual Benefit Payments (Detail) - Foreign Postretirement Benefit Plan $ in Thousands	Dec. 31, 2016USD ($)
UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Expected future benefit payments in 2017	$ 64
Expected future benefit payments in 2018	65
Expected future benefit payments in 2019	68
Expected future benefit payments in 2020	70
Expected future benefit payments in 2021	73
Expected future benefit payments in Years 2022 - 2026	362
SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Expected future benefit payments in 2017	305
Expected future benefit payments in 2018	306
Expected future benefit payments in 2019	685
Expected future benefit payments in 2020	251
Expected future benefit payments in 2021	249
Expected future benefit payments in Years 2022 - 2026	$ 1,676

Funded Status - Switzerland (De

Funded Status - Switzerland (Detail) - Foreign Postretirement Benefit Plan - SWITZERLAND - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ (6,928)	$ (8,537)
Fair value of plan assets	6,006	5,350	$ 7,061
Funded status	(922)	(3,187)
Non-current other liabilities (note 8)	$ (922)	$ (3,187)

Equity Incentive Schemes and 86

Equity Incentive Schemes and Stock Compensation Charges - Additional Information (Detail) - USD ($) $ in Thousands	Feb. 14, 2017	May 11, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2017
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Weighted average contractual term of options outstanding			4 years 8 months 1 day	4 years 9 months 4 days
Exercisable - weighted average remaining contractual life			3 years 3 months 18 days	3 years 4 months 21 days
Options expected to vest			336,993			336,993
Intrinsic value of option exercised			$ 19,600
Intrinsic value of option outstanding			46,600			$ 46,600
Intrinsic value of option exercisable			29,600			29,600
Share-based compensation expense			40,343	$ 33,317	$ 22,742
Non-cash stock compensation expense not yet recognized			$ 64,900			$ 64,900
Unrecognized stock-based compensation expense, weighted average period (years)			2 years 26 days
Tax benefit on exercise of options			$ 4,332	1,905	$ 2,404
Income tax expense related to stock compensation			3,500	1,500
Cash tax benefit related to stock options exercised			$ 3,400	5,600
Scenario, Forecast
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Options expected to vest							333,433
Employee Stock Plan, 2008 Plan
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance			6,000,000			6,000,000
Employee Stock Plan, 2008 Plan | Individual Employee
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance			400,000			400,000
Employee Stock Plan, 2008 Plan | Minimum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Percentage of option price for fair value of ordinary share			100.00%
Employee Stock Plan, 2008 Plan | Minimum | Subsequent Event
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Additional number of ordinary shares which have been reserved for issuance	400,000
Employee Stock Plan, 2008 Plan | Maximum | Subsequent Event
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Additional number of ordinary shares which have been reserved for issuance	1,000,000
Employee Stock Plan, 2003 Plan
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance			6,000,000			6,000,000
Maximum number of award as percentage of shares outstanding			10.00%
Employee Stock Plan, 2003 Plan | Individual Employee
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance			400,000			400,000
Employee Stock Option
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Shares vesting period			5 years
Shares expiration period			8 years
Employee Stock Option | Vested and Unvested Options
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Options vesting percentage			20.00%
Employee Stock Option | Maximum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Weighted average contractual term of options outstanding			8 years
Restricted Stock Units 2008
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance			1,000,000			1,000,000
Restricted Stock Units 2013
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Additional number of ordinary shares which have been reserved for issuance		2,500,000
Ordinary shares which have been reserved for issuance		4,100,000
Restricted Stock Units (RSUs)
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Fair value of stock units vested			$ 10,800	7,000
Stock units granted			391,196
Performance Share Unit (PSUs)
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Fair value of stock units vested			$ 10,300	$ 300
Stock units granted			247,992
PSUs Based on Service and EPS Targets
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Stock units granted						421,079
PSUs Based on Service and EPS Targets | Minimum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Cumulative EPS vesting period			2,013
PSUs Based on Service and EPS Targets | Maximum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Stock units to be granted			409,444			409,444
Cumulative EPS vesting period			2,019

Summary of Stock Option Activit

Summary of Stock Option Activity (Detail) - Stock Option And Award Plans - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Options Granted Under Plans
Beginning balance	1,626,582	2,227,700	2,973,788
Granted	256,191	259,059	366,985
Exercised	(393,240)	(773,753)	(926,407)
Cancelled	(23,089)	(86,424)	(186,666)
Ending Balance	1,466,444	1,626,582	2,227,700
Vested and exercisable at end of period	651,574
Number of Shares
Beginning balance	1,626,582	2,227,700	2,973,788
Granted	256,191	259,059	366,985
Exercised	(393,240)	(773,753)	(926,407)
Cancelled	(23,089)	(86,424)	(186,666)
Ending balance	1,466,444	1,626,582	2,227,700
Vested and exercisable at end of period	651,574
Weighted Average Exercise Price
Beginning balance	$ 34.87	$ 28	$ 24.20
Granted	69.61	68.25	45.82
Exercised	25.79	27.13	24.02
Cancelled	29.74	27.32	22.17
Ending balance	43.45	34.87	28
Vested and exercisable at end of period	29.80
Weighted Average Grant Date Fair Value
Beginning balance	11.94	10.40	9.57
Granted	20.10	19.75	14.09
Exercised	9.84	10.31	9.45
Cancelled	11.19	10.31	9.01
Ending balance	13.94	$ 11.94	$ 10.40
Vested and exercisable at end of period	$ 10.69

Summary of Movement in Non-Vest

Summary of Movement in Non-Vested Share Options (Detail) - Employee Stock Option - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Options Outstanding Number of Shares
Beginning Balance	968,853
Granted	256,191
Vested	(391,918)
Forfeited	(18,256)
Ending Balance	814,870	968,853
Weighted Average Exercise Price
Beginning balance	$ 42.14
Granted	69.61
Vested	35.17
Forfeited	31.48
Ending balance	54.37	$ 42.14
Weighted Average Fair Value
Beginning Balance	13.69
Granted	20.10	19.75	$ 14.09
Vested	12.04
Forfeited	11.62
Ending Balance	$ 16.55	$ 13.69

Outstanding and Exercisable Sha

Outstanding and Exercisable Share Options (Detail)	12 Months Ended
	Dec. 31, 2016$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 71.95
Range Exercise Price Minimum	$ 15.84
Options Outstanding Number of Shares | shares	1,466,444
Options Outstanding Weighted Average Remaining Contractual Life	4 years 8 months 1 day
Options Outstanding Weighted Average Exercise Price	$ 43.45
Options Exercisable Number of Shares | shares	651,574
Options Exercisable Weighted Average Exercise Price	$ 29.80
Range 1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 15.84
Options Outstanding Number of Shares | shares	50,000
Options Outstanding Weighted Average Remaining Contractual Life	3 months 26 days
Options Outstanding Weighted Average Exercise Price	$ 15.84
Options Exercisable Number of Shares | shares	50,000
Options Exercisable Weighted Average Exercise Price	$ 15.84
Range 2
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 16.80
Options Outstanding Number of Shares | shares	60,000
Options Outstanding Weighted Average Remaining Contractual Life	2 years 9 months 29 days
Options Outstanding Weighted Average Exercise Price	$ 16.80
Options Exercisable Number of Shares | shares	60,000
Options Exercisable Weighted Average Exercise Price	$ 16.80
Range 3
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 17.17
Options Outstanding Number of Shares | shares	6,000
Options Outstanding Weighted Average Remaining Contractual Life	2 years 10 months 6 days
Options Outstanding Weighted Average Exercise Price	$ 17.17
Options Exercisable Number of Shares | shares	6,000
Options Exercisable Weighted Average Exercise Price	$ 17.17
Range 4
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 20.28
Options Outstanding Number of Shares | shares	107,588
Options Outstanding Weighted Average Remaining Contractual Life	2 years 1 month 28 days
Options Outstanding Weighted Average Exercise Price	$ 20.28
Options Exercisable Number of Shares | shares	107,588
Options Exercisable Weighted Average Exercise Price	$ 20.28
Range 5
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 20.59
Options Outstanding Number of Shares | shares	33,000
Options Outstanding Weighted Average Remaining Contractual Life	3 years 1 month 21 days
Options Outstanding Weighted Average Exercise Price	$ 20.59
Options Exercisable Number of Shares | shares	7,200
Options Exercisable Weighted Average Exercise Price	$ 20.59
Range 6
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 22.26
Options Outstanding Number of Shares | shares	2,160
Options Outstanding Weighted Average Remaining Contractual Life	1 month 24 days
Options Outstanding Weighted Average Exercise Price	$ 22.26
Options Exercisable Number of Shares | shares	2,160
Options Exercisable Weighted Average Exercise Price	$ 22.26
Range 7
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 22.30
Options Outstanding Number of Shares | shares	173,642
Options Outstanding Weighted Average Remaining Contractual Life	3 years 3 months 26 days
Options Outstanding Weighted Average Exercise Price	$ 22.30
Options Exercisable Number of Shares | shares	112,061
Options Exercisable Weighted Average Exercise Price	$ 22.30
Range 8
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 23.66
Options Outstanding Number of Shares | shares	3,520
Options Outstanding Weighted Average Remaining Contractual Life	3 years 6 months 26 days
Options Outstanding Weighted Average Exercise Price	$ 23.66
Options Exercisable Number of Shares | shares	1,910
Options Exercisable Weighted Average Exercise Price	$ 23.66
Range 9
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 24.46
Options Outstanding Number of Shares | shares	60,816
Options Outstanding Weighted Average Remaining Contractual Life	1 year 2 months 1 day
Options Outstanding Weighted Average Exercise Price	$ 24.46
Options Exercisable Number of Shares | shares	60,816
Options Exercisable Weighted Average Exercise Price	$ 24.46
Range 10
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 26.20
Options Outstanding Number of Shares | shares	450
Options Outstanding Weighted Average Remaining Contractual Life	1 year 4 months 17 days
Options Outstanding Weighted Average Exercise Price	$ 26.20
Options Exercisable Number of Shares | shares	450
Options Exercisable Weighted Average Exercise Price	$ 26.20
Range 11
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 26.71
Options Outstanding Number of Shares | shares	4,450
Options Outstanding Weighted Average Remaining Contractual Life	3 years 8 months 9 days
Options Outstanding Weighted Average Exercise Price	$ 26.71
Options Exercisable Number of Shares | shares	3,560
Options Exercisable Weighted Average Exercise Price	$ 26.71
Range 12
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 29.45
Options Outstanding Number of Shares | shares	3,000
Options Outstanding Weighted Average Remaining Contractual Life	1 year 3 months 26 days
Options Outstanding Weighted Average Exercise Price	$ 29.45
Options Exercisable Number of Shares | shares	3,000
Options Exercisable Weighted Average Exercise Price	$ 29.45
Range 13
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 32.37
Options Outstanding Number of Shares | shares	165,865
Options Outstanding Weighted Average Remaining Contractual Life	4 years 3 months 29 days
Options Outstanding Weighted Average Exercise Price	$ 32.37
Options Exercisable Number of Shares | shares	95,457
Options Exercisable Weighted Average Exercise Price	$ 32.37
Range 14
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 36.22
Options Outstanding Number of Shares | shares	20,178
Options Outstanding Weighted Average Remaining Contractual Life	4 years 5 months 16 days
Options Outstanding Weighted Average Exercise Price	$ 36.22
Options Exercisable Number of Shares | shares	8,443
Options Exercisable Weighted Average Exercise Price	$ 36.22
Range 15
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 37.90
Options Outstanding Number of Shares | shares	5,720
Options Outstanding Weighted Average Remaining Contractual Life	4 years 11 months 5 days
Options Outstanding Weighted Average Exercise Price	$ 37.90
Options Exercisable Number of Shares | shares	1,600
Options Exercisable Weighted Average Exercise Price	$ 37.90
Range 16
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 40.83
Options Outstanding Number of Shares | shares	81,658
Options Outstanding Weighted Average Remaining Contractual Life	5 years 4 months 21 days
Options Outstanding Weighted Average Exercise Price	$ 40.83
Options Exercisable Number of Shares | shares	24,646
Options Exercisable Weighted Average Exercise Price	$ 40.83
Range 17
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 47.03
Options Outstanding Number of Shares | shares	63,813
Options Outstanding Weighted Average Remaining Contractual Life	5 years 2 months 1 day
Options Outstanding Weighted Average Exercise Price	$ 47.03
Options Exercisable Number of Shares | shares	15,693
Options Exercisable Weighted Average Exercise Price	$ 47.03
Range 18
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 48.67
Options Outstanding Number of Shares | shares	118,493
Options Outstanding Weighted Average Remaining Contractual Life	5 years 2 months 16 days
Options Outstanding Weighted Average Exercise Price	$ 48.67
Options Exercisable Number of Shares | shares	22,992
Options Exercisable Weighted Average Exercise Price	$ 48.67
Range 19
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 51.35
Options Outstanding Number of Shares | shares	4,030
Options Outstanding Weighted Average Remaining Contractual Life	5 years 7 months 6 days
Options Outstanding Weighted Average Exercise Price	$ 51.35
Options Exercisable Number of Shares | shares	1,612
Options Exercisable Weighted Average Exercise Price	$ 51.35
Range 20
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 65.60
Options Outstanding Number of Shares | shares	93,534
Options Outstanding Weighted Average Remaining Contractual Life	7 years 4 months 17 days
Options Outstanding Weighted Average Exercise Price	$ 65.60
Options Exercisable Number of Shares | shares	10,557
Options Exercisable Weighted Average Exercise Price	$ 65.60
Range 21
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 66.47
Options Outstanding Number of Shares | shares	11,931
Options Outstanding Weighted Average Remaining Contractual Life	6 years 4 months 21 days
Options Outstanding Weighted Average Exercise Price	$ 66.47
Options Exercisable Number of Shares | shares	1,417
Options Exercisable Weighted Average Exercise Price	$ 66.47
Range 22
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 66.97
Options Outstanding Number of Shares | shares	3,118
Options Outstanding Weighted Average Remaining Contractual Life	6 years 5 months 12 days
Options Outstanding Weighted Average Exercise Price	$ 66.97
Options Exercisable Number of Shares | shares	623
Options Exercisable Weighted Average Exercise Price	$ 66.97
Range 23
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 68.39
Options Outstanding Number of Shares | shares	231,687
Options Outstanding Weighted Average Remaining Contractual Life	6 years 2 months 5 days
Options Outstanding Weighted Average Exercise Price	$ 68.39
Options Exercisable Number of Shares | shares	53,789
Options Exercisable Weighted Average Exercise Price	$ 68.39
Range 24
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 71.95
Options Outstanding Number of Shares | shares	161,791
Options Outstanding Weighted Average Remaining Contractual Life	7 years 2 months 1 day
Options Outstanding Weighted Average Exercise Price	$ 71.95
Options Exercisable Weighted Average Exercise Price	$ 71.95

Schedule of Weighted Average Fa

Schedule of Weighted Average Fair Values and Assumptions Used (Detail) - Employee Stock Option - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value	$ 20.10	$ 19.75	$ 14.09
Assumptions:
Expected volatility	30.00%	30.00%	32.00%
Dividend yield	0.00%	0.00%	0.00%
Risk-free interest rate	1.39%	1.58%	1.57%
Expected life	5 years	5 years	5 years

Summary of RSU and PSU Activity

Summary of RSU and PSU Activity (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Performance Share Unit (PSUs)
Outstanding Number of Shares
Outstanding at beginning of period	901,773
Granted	247,992
Shares vested	(311,492)
Forfeited	(7,750)
Outstanding at ending of period	830,523	901,773
Weighted Average Fair Value
Outstanding at beginning of period	$ 48.33
Granted	71.58
Shares vested	33.09
Forfeited	56.58
Outstanding at end of period	$ 60.73	$ 48.33
Weighted Average Remaining Contractual Life
Outstanding at end of period	1 year 1 month 10 days	1 year 2 months 19 days
Restricted Stock Units (RSUs)
Outstanding Number of Shares
Outstanding at beginning of period	1,067,613
Granted	391,196
Shares vested	(300,019)
Forfeited	(133,306)
Outstanding at ending of period	1,025,484	1,067,613
Weighted Average Fair Value
Outstanding at beginning of period	$ 48.30
Granted	67.45
Shares vested	36.13
Forfeited	52.36
Outstanding at end of period	$ 58.64	$ 48.30
Weighted Average Remaining Contractual Life
Outstanding at end of period	1 year 4 months 24 days	1 year 5 months 23 days

Schedule of Non-cash Stock Comp

Schedule of Non-cash Stock Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 40,343	$ 33,317	$ 22,742
Direct costs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	21,903	18,358	12,531
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 18,440	$ 14,959	$ 10,211

Government Grants (Detail)

Government Grants (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Government Grants [Line Items]
Received	$ 3,539	$ 3,539
Less accumulated amortization	(2,701)	(2,657)
Foreign exchange translation adjustment	103	120
Total government grants	941	1,002
Less current portion	(54)	(43)
Non-current government grants	$ 887	$ 959	[1]
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).

Government Grants - Additional

Government Grants - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Government Grants [Line Items]
Amortization of government grants	$ 44	$ (53)	$ 213
Restricted retained earnings	$ 600

Share Capital - Additional Info

Share Capital - Additional Information (Detail) - USD ($)	Oct. 03, 2016	Jul. 31, 2015	May 01, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Equity, Class of Treasury Stock [Line Items]
Share allotment description				Every holder of an ordinary share present in person or proxy at a general meeting of shareholders shall have one vote, for each ordinary share held with no individual having more than one vote.
Ordinary shares redeemed, value				$ 110,000,000	$ 457,892,000	$ 140,030,000
Ordinary shares repurchased						2,640,610
Ordinary shares repurchased, value						$ 140,000,000
Employee Stock Option
Equity, Class of Treasury Stock [Line Items]
Options exercised by employees				393,240	773,753	926,407
Average exercise price of Option per share				$ 25.79	$ 27.13	$ 24.02
Total proceeds from exercise of stock options by employees				$ 10,100,000	$ 21,000,000	$ 22,300,000
Restricted Stock Units (RSUs)
Equity, Class of Treasury Stock [Line Items]
Ordinary shares issued in respect of certain RSUs previously awarded by the Company				296,386	268,870	233,726
Performance Share Unit (PSUs)
Equity, Class of Treasury Stock [Line Items]
Ordinary shares issued in respect of certain PSUs previously awarded by the Company				311,492	7,990
Buyback Program
Equity, Class of Treasury Stock [Line Items]
Ordinary shares redeemed		5,316,062	882,419	1,429,187	6,198,481
Ordinary shares redeemed, value		$ 400,000,000	$ 57,900,000	$ 110,000,000	$ 457,900,000
Stock repurchase program, authorized amount	$ 400,000,000	$ 400,000,000	$ 60,000,000
Buyback Program | Maximum
Equity, Class of Treasury Stock [Line Items]
Share repurchase program, authorized percentage	10.00%

Components of Income Before Pro

Components of Income Before Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items]
Income before provision for income taxes	$ 300,172	$ 278,850	$ 202,716
Ireland
Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items]
Income before provision for income taxes	201,221	184,643	143,889
United States
Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items]
Income before provision for income taxes	11,466	15,436	6,966
Other
Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items]
Income before provision for income taxes	$ 87,485	$ 78,771	$ 51,861

Components of Provision for Inc

Components of Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current tax expense:
Current tax expense	$ 36,448	$ 36,154	$ 38,148
Deferred expense/(benefit):
Deferred tax expense/(benefit)	1,545	3,157	(7,900)
Provision for income taxes	37,993	39,311	30,248
Impact on shareholders equity and other comprehensive income of the tax consequence of :
Excess tax benefit on stock compensation	(4,332)	(1,905)	(2,404)
Currency impact on long term funding	(396)	3,574	178
Total	33,265	40,980	28,022
Ireland
Current tax expense:
Current tax expense	22,931	21,769	19,562
Deferred expense/(benefit):
Deferred tax expense/(benefit)	1,284	26	(1,178)
Provision for income taxes	24,215	21,795	18,384
United States
Current tax expense:
Current tax expense	7,768	684	7,891
Deferred expense/(benefit):
Deferred tax expense/(benefit)	613	2,896	(3,031)
Provision for income taxes	8,381	3,580	4,860
Other
Current tax expense:
Current tax expense	5,749	13,701	10,695
Deferred expense/(benefit):
Deferred tax expense/(benefit)	(352)	235	(3,691)
Provision for income taxes	$ (131)	$ 5,929	$ 4,149

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Irish statutory rate	12.50%	12.50%	12.50%
Valuation allowance for deferred tax assets	$ 20,337	$ 17,184	$ 23,145
Net change in the total valuation allowance	3,100	(5,900)
Deferred tax expense/(benefit) resulted from valuation allowance release		3,200
Unrecognized tax benefit, potentially expire in 2016	4,900
Increase related to acquired tax positions	0	778	14,552
Total unrecognized tax benefits net of potential benefits	26,620	28,166	23,201
Interest and penalties recognized as an expense	100	900	$ 200
Total accrued interest and penalties	$ 3,300	3,300
Tax Jurisdiction Description	In the United States tax periods open to audit include the years ended December 31, 2013, December 31, 2014, December 31, 2015 and December 31, 2016. In Ireland, tax periods open to audit include the years ended December 31, 2012, December 31, 2013, December 31, 2014, December 31, 2015 and December 31, 2016. During such audits, local tax authorities may challenge the positions taken by us in tax returns.
Provision for income taxes
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Net change in the total valuation allowance	$ 1,200	(4,100)
Goodwill
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Net change in the total valuation allowance	2,400
Other Comprehensive Income
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Net change in the total valuation allowance	(500)	(1,800)
Foreign Country
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Ireland subsidiaries additional tax credit carryforward for income tax	3,300	2,900
Other non-U.S subsidiaries operating loss carryforwards for income tax	70,100	68,600
Other non-U.S subsidiaries tax credit carryforwards for income tax	3,900	$ 3,000
Additional operating loss carryforward	$ 3,500
Expiration period	Expire between 2017 and 2023.
Ireland
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Irish statutory rate	12.50%
United States
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Expiration period	Expire between 2017 and 2036
U.S. Federal net operating loss carry forwards currently available for offset	$ 22,800
Limitation description	Due to changes of ownership in 2000, 2010 and 2014, as defined by Section 382 of the Internal Revenue Code of 1986, as amended.
Alternative minimum tax credit carry forwards	$ 400
Business credit carry forwards that are available to offset	300
United States | Federal
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Additional operating loss carryforward	50,587
U.S. federal net operating loss carry forwards	28,600
United States | Additional Paid-in Capital | Federal
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Additional operating loss carryforward	16,100
United States | 2016 | Federal
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
U.S. federal net operating loss carry forwards	2,900
United States | 2017 - 2019 | Federal
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
U.S. federal net operating loss carry forwards	12,800
United States | 2020 - 2022 | Federal
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
U.S. federal net operating loss carry forwards	7,700
United States | 2023 - 2026 | Federal
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
U.S. federal net operating loss carry forwards	5,200
United States | State
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Additional operating loss carryforward	50,168
United States | State | Additional Paid-in Capital
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Additional operating loss carryforward	$ 30,900

Consolidated Reported Provision

Consolidated Reported Provision for Income Taxes Differed from Statutory Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Deferred Income Tax Assets and Liabilities [Line Items]
Taxes at Irish statutory rate of 12.5% (2015:12.5%; 2014:12.5%)	$ 37,522	$ 34,856	$ 25,340
Foreign and other income taxed at higher rates	4,642	4,614	3,152
Research & development tax incentives	(907)	(695)	(1,810)
Movement in valuation allowance	1,208	(4,133)	(1,965)
Effects of change in tax rates	576	(16)	543
Increase/(decrease) in unrecognized tax benefits	(1,521)	5,085	2,869
Effects of permanent items	(4,259)	(463)	2,048
Other	732	63	71
Provision for income taxes	$ 37,993	$ 39,311	$ 30,248

Consolidated Reported Provis100

Consolidated Reported Provision for Income Taxes Differed from Statutory Rate (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Deferred Income Tax Assets and Liabilities [Line Items]
Irish statutory rate	12.50%	12.50%	12.50%

Tax Effects of Temporary Differ

Tax Effects of Temporary Differences That Gives Rise to Significant Portions of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Deferred tax liabilities:
Property, plant and equipment	$ 979	$ 1,239
Goodwill	26,617	22,170
Other intangible assets	6,700	5,865
Other	1,441	1,293
Total deferred tax liabilities recognized	35,737	30,567
Deferred tax assets:
Operating loss and tax credits carryforwards	22,705	22,186
Property, plant and equipment	3,121	2,487
Accrued expenses and payments on account	28,904	29,473
Stock compensation	13,062	12,959
Deferred compensation expense	3,327	2,174
Other	15	566
Total deferred tax assets	71,134	69,845
Valuation allowance for deferred tax assets	(20,337)	(17,184)	$ (23,145)
Deferred tax assets recognized	50,797	52,661
Overall net deferred tax asset	$ 15,060	$ 22,094

Expected Expiry Dates of NOI's

Expected Expiry Dates of NOI's (Detail) - United States $ in Thousands	Dec. 31, 2016USD ($)
Federal
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward	$ 50,587
Federal | Expiring 2017-2018
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward	226
Federal | Expiring 2021-2034
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward	34,735
Federal | Expiring 2035-2036
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward	15,626
State
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward	50,168
State | Expiring 2021-2034
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward	29,049
State | Expiring 2035-2036
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward	$ 21,119

Reconciliation of Beginning and

Reconciliation of Beginning and Ending Amount of Total Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Contingency [Line Items]
Unrecognized tax benefits at start of year	$ 28,166	$ 23,201	$ 5,780
Increase related to acquired tax positions	0	778	14,552
Increase related to prior year tax positions	1,151	1,482	565
Decrease related to prior year tax positions	(2,483)	(315)	(183)
Increase related to current year tax positions	1,104	3,063	3,709
Settlements	(837)		(2)
Lapse of statute of limitations	(481)	(43)	(1,220)
Unrecognized tax benefits at end of year	$ 26,620	$ 28,166	$ 23,201

Recognized Restructuring and Ot

Recognized Restructuring and Other Items, Net (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2014
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 8,159	$ 8,796
Net charge	$ 8,159	$ 8,796

Restructuring and Other Items -

Restructuring and Other Items - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2014	Dec. 31, 2015
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 8,159	$ 8,796
Restructuring and other items	2,432		$ 2,116
Resource Rationalizations
Restructuring Cost and Reserve [Line Items]
Restructuring charges	8,159
Onerous Lease | Resource Rationalizations
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1,969
Workforce reduction | Resource Rationalizations
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 6,190
Manchester, United Kingdom facility closure
Restructuring Cost and Reserve [Line Items]
Restructuring charges		8,796
Manchester, United Kingdom facility closure | Asset Impairment
Restructuring Cost and Reserve [Line Items]
Restructuring charges		5,629
Manchester, United Kingdom facility closure | Onerous Lease
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 3,167

Restructuring Charges (Detail)

Restructuring Charges (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restructuring Cost and Reserve [Line Items]
Total provision recognized	$ 8,159		$ 8,796
Manchester, United Kingdom facility closure
Restructuring Cost and Reserve [Line Items]
Total provision recognized			8,796
Utilized	(1,359)	$ (1,167)
Asset write-off			(5,629)
Closing provision	641	2,000	3,167
Resource Rationalizations
Restructuring Cost and Reserve [Line Items]
Total provision recognized	8,159
Utilized	(6,305)
Foreign exchange	(63)
Closing provision	1,791
Workforce reduction | Resource Rationalizations
Restructuring Cost and Reserve [Line Items]
Total provision recognized	6,190
Utilized	(5,734)
Foreign exchange	(63)
Closing provision	393
Onerous Lease | Manchester, United Kingdom facility closure
Restructuring Cost and Reserve [Line Items]
Total provision recognized			3,167
Utilized	(1,359)	(1,167)
Closing provision	641	$ 2,000	3,167
Onerous Lease | Resource Rationalizations
Restructuring Cost and Reserve [Line Items]
Total provision recognized	1,969
Utilized	(571)
Closing provision	$ 1,398
Asset Impairment | Manchester, United Kingdom facility closure
Restructuring Cost and Reserve [Line Items]
Total provision recognized			5,629
Asset write-off			$ (5,629)

Provision for Doubtful Debts (D

Provision for Doubtful Debts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Opening provision	$ 10,383	$ 5,458
Amounts used during the year	(3,782)	(161)
Amounts provided during the year	4,651	7,572
Amounts released during the year	(1,814)	(2,244)
Translation	12	(242)
Closing provision	$ 9,450	$ 10,383

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating Leased Assets [Line Items]
Non-cancelable operating leases for facilities expiration period	10 years
Operating leases rental expense	$ 44	$ 49.9	$ 54.3

Future Minimum Rental Commitmen

Future Minimum Rental Commitments for Operating Leases (Detail) $ in Thousands	Dec. 31, 2016USD ($)
Operating Leased Assets [Line Items]
2,017	$ 34,682
2,018	28,219
2,019	21,358
2,020	15,646
2,021	12,477
Thereafter	40,132
Total	$ 152,514

Distribution of Net Revenue by

Distribution of Net Revenue by Geographical Area (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Net Revenue	$ 1,666,487	$ 1,574,978	$ 1,503,316
Ireland
Segment Reporting Information [Line Items]
Net Revenue	410,572	429,631	360,376
Rest Of Europe
Segment Reporting Information [Line Items]
Net Revenue	313,185	330,487	372,634
United States
Segment Reporting Information [Line Items]
Net Revenue	763,821	650,941	605,815
Other
Segment Reporting Information [Line Items]
Net Revenue	$ 178,909	$ 163,919	$ 164,491

Distribution of Income from ope

Distribution of Income from operations, including Restructuring, by Geographical Area (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Income from operations	$ 311,694	$ 281,536	$ 202,350
Ireland
Segment Reporting Information [Line Items]
Income from operations	216,149	189,035	138,185
Rest Of Europe
Segment Reporting Information [Line Items]
Income from operations	34,200	38,166	14,481
United States
Segment Reporting Information [Line Items]
Income from operations	41,348	45,320	39,058
Other
Segment Reporting Information [Line Items]
Income from operations	$ 19,997	$ 9,015	$ 10,626

Distribution of Income from 112

Distribution of Income from operations, excluding Restructuring, by Geographical Area (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Income from operations, excluding restructuring and other items	$ 319,853	$ 281,536	$ 211,146
Ireland
Segment Reporting Information [Line Items]
Income from operations, excluding restructuring and other items	218,334	189,035	138,185
Rest Of Europe
Segment Reporting Information [Line Items]
Income from operations, excluding restructuring and other items	36,509	38,166	23,277
United States
Segment Reporting Information [Line Items]
Income from operations, excluding restructuring and other items	44,590	45,320	39,058
Other
Segment Reporting Information [Line Items]
Income from operations, excluding restructuring and other items	$ 20,420	$ 9,015	$ 10,626

Distribution of Property, Plant

Distribution of Property, Plant and Equipment, Net, by Geographical Area (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Property, plant and equipment, net	$ 148,967	$ 150,218	[1]
Ireland
Segment Reporting Information [Line Items]
Property, plant and equipment, net	105,684	101,736
Rest Of Europe
Segment Reporting Information [Line Items]
Property, plant and equipment, net	6,231	7,334
United States
Segment Reporting Information [Line Items]
Property, plant and equipment, net	29,428	34,520
Other
Segment Reporting Information [Line Items]
Property, plant and equipment, net	$ 7,624	$ 6,628
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).

Distribution of Depreciation an

Distribution of Depreciation and Amortization by Geographical Area (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Depreciation and amortization	$ 59,575	$ 57,677	$ 52,542
Ireland
Segment Reporting Information [Line Items]
Depreciation and amortization	25,766	22,100	20,731
Rest Of Europe
Segment Reporting Information [Line Items]
Depreciation and amortization	6,914	11,055	7,478
United States
Segment Reporting Information [Line Items]
Depreciation and amortization	23,462	20,106	20,491
Other
Segment Reporting Information [Line Items]
Depreciation and amortization	$ 3,433	$ 4,416	$ 3,842

Distribution of Total Assets by

Distribution of Total Assets by Geographical Area (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	[2]
Segment Reporting Information [Line Items]
Assets	$ 1,825,843	$ 1,717,209	[1]
Ireland
Segment Reporting Information [Line Items]
Assets	766,120	663,060
Rest Of Europe
Segment Reporting Information [Line Items]
Assets	337,062	343,733
United States
Segment Reporting Information [Line Items]
Assets	651,160	641,769
Other
Segment Reporting Information [Line Items]
Assets	$ 71,501	$ 68,647
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).
[2]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs.

Distribution of Capital Expendi

Distribution of Capital Expenditure by Geographical Area (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Purchase of property, plant and equipment	$ 42,601	$ 49,730	$ 32,779
Ireland
Segment Reporting Information [Line Items]
Purchase of property, plant and equipment	27,670	30,900	15,117
Rest Of Europe
Segment Reporting Information [Line Items]
Purchase of property, plant and equipment	2,851	1,916	2,278
United States
Segment Reporting Information [Line Items]
Purchase of property, plant and equipment	8,432	15,256	12,224
Other
Segment Reporting Information [Line Items]
Purchase of property, plant and equipment	$ 3,648	$ 1,658	$ 3,160

Clients Representing Company's

Clients Representing Company's Net Revenue (Detail)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Customer Concentration Risk [Member] | Sales Revenue, Net | Client A
Revenue, Major Customer [Line Items]
Clients which represented 10% or more of the company's net revenue	26.00%	31.00%	31.00%

Distribution of Interest Income

Distribution of Interest Income by Geographical Area (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Interest income	$ 1,484	$ 1,306	$ 1,151
Ireland
Segment Reporting Information [Line Items]
Interest income	407	102	284
Rest Of Europe
Segment Reporting Information [Line Items]
Interest income	1,040	1,151	798
United States
Segment Reporting Information [Line Items]
Interest income	2	4
Other
Segment Reporting Information [Line Items]
Interest income	$ 35	$ 49	$ 69

Distribution of Income Tax Char

Distribution of Income Tax Charge by Geographical Area (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Provision for income taxes	$ 37,993	$ 39,311	$ 30,248
Ireland
Segment Reporting Information [Line Items]
Provision for income taxes	24,215	21,795	18,384
Rest Of Europe
Segment Reporting Information [Line Items]
Provision for income taxes	5,528	8,007	2,855
United States
Segment Reporting Information [Line Items]
Provision for income taxes	8,381	3,580	4,860
Other
Segment Reporting Information [Line Items]
Provision for income taxes	$ (131)	$ 5,929	$ 4,149

Supplemental Disclosure of C120

Supplemental Disclosure of Cash Flow Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Cash Flow, Supplemental [Line Items]
Cash paid for interest	$ 13,615	$ 2,175	$ 533
Cash paid for income taxes	$ 10,205	$ 14,829	$ 17,829

Accumulated Other Comprehens121

Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Currency translation adjustments	$ (70,154)	$ (57,315)
Currency impact on long term funding (Net of tax)	(13,912)	(5,484)
Actuarial loss on defined benefit pension plan (note 9)	(5,905)	(3,420)
Unrealized capital gain/(loss) - investments (note 3)	(23)	(34)
Net realized gain on interest rate hedge	3,694	4,617
Total	$ (86,300)	$ (61,636)	[1]
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).

Long-Term Debt - Senior Notes -

Long-Term Debt - Senior Notes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Long term debt	$ 348,511,000	$ 348,306,000	[1]
Cash proceeds from interest rate hedge		4,658,000
Restatement Adjustment
Debt Instrument [Line Items]
Debt issue costs		(1,694,000)
Senior Notes
Debt Instrument [Line Items]
Long term debt		350,000,000
Cash proceeds from interest rate hedge		$ 4,658,000
Interest rate hedge, maturity date	Nov. 17, 2015
Interest rate hedge, inception date	Oct. 5, 2015
[1]	The December 31, 2015 Balance Sheet has been retrospectively restated as required to reflect the requirements of new guidance in respect of the presentation of debt issue costs (see Note 20).

Related Parties - Additional In

Related Parties - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2016USD ($)	Dec. 31, 2016EUR (€)	Dec. 31, 2015USD ($)	Dec. 31, 2016EUR (€)
Subsidiaries | Dignity Sciences Limited
Related Party Transaction [Line Items]
Revenue earned from related parties	$ 100,000		$ 100,000
Amounts due from related parties	45,700
Mr. Thomas Lynch
Related Party Transaction [Line Items]
Related party transaction amounts	$ 256,315	€ 231,750
Amounts due to related parties | €				€ 96,560
Term of agreement	3 years	3 years
Related party agreement beginning date	Aug. 1, 2016	Aug. 1, 2016