Charles River Laboratories International (CRL) 10-K 12 Feb 16 2015 FY Annual report Financial data

Document and Entity Information

Document and Entity Information Document - USD ($)	12 Months Ended
	Dec. 26, 2015	Jan. 29, 2016	Jun. 27, 2015
Document and Entity Information [Abstract]
Entity Registrant Name	CHARLES RIVER LABORATORIES INTERNATIONAL INC
Entity Central Index Key	1,100,682
Current Fiscal Year End Date	--12-26
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 26, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Common Stock, Shares Outstanding		46,718,000
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 3,300,699,578

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Income Statement [Abstract]
Service revenue	$ 858,244	$ 797,765	$ 689,166
Product revenue	505,058	499,897	476,362
Total revenue	1,363,302	1,297,662	1,165,528
Costs and expenses:
Cost of services provided (excluding amortization of intangible assets)	568,227	558,578	497,876
Cost of products sold (excluding amortization of intangible assets)	263,983	266,424	272,750
Selling, general and administrative	300,414	269,033	225,695
Amortization of intangible assets	24,229	25,957	17,806
Operating income	206,449	177,670	151,401
Other income (expense):
Interest income	1,043	1,154	730
Interest expense	(15,072)	(11,950)	(20,969)
Other income (expense), net	3,008	10,721	7,165
Income from continuing operations, before income taxes	195,428	177,595	138,327
Provision for income taxes	43,391	47,671	32,911
Income from continuing operations, net of income taxes	152,037	129,924	105,416
Loss from discontinued operations, net of income taxes	(950)	(1,726)	(1,265)
Net income	151,087	128,198	104,151
Less: Net income attributable to noncontrolling interests	(1,774)	(1,500)	(1,323)
Net income attributable to common shareholders	$ 149,313	$ 126,698	$ 102,828
Basic:
Continuing operations attributable to common shareowners (in dollars per share)	$ 3.23	$ 2.76	$ 2.18
Discontinued operations (in dollars per share)	(0.02)	(0.04)	(0.03)
Net income attributable to common shareowners (in dollars per share)	3.21	2.72	2.15
Diluted:
Continuing operations attributable to common shareowners (in dollars per share)	3.15	2.70	2.15
Discontinued operations (in dollars per share)	(0.02)	(0.04)	(0.03)
Net income attributable to common shareowners (in dollars per share)	$ 3.13	$ 2.66	$ 2.12

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 151,087	$ 128,198	$ 104,151
Foreign currency translation adjustment and other	(61,982)	(48,955)	(15,322)
Cumulative translation adjustment related to intercompany loan forgiveness	(2,341)	0	0
Pension and other post-retirement benefit plans:
Prior service cost and gains (losses) arising during the period	(302)	(42,236)	19,293
Amortization of net gains (losses) and prior service benefit included in net periodic pension cost	2,617	1,234	3,017
Comprehensive income, before income taxes	89,079	38,241	111,139
Income tax expense (benefit) related to items of other comprehensive income	530	(9,897)	7,805
Comprehensive income, net of income taxes	88,549	48,138	103,334
Less: Comprehensive income related to noncontrolling interests	537	1,044	1,752
Comprehensive income attributable to common shareholders	$ 88,012	$ 47,094	$ 101,582

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014
Current assets:
Cash and cash equivalents	$ 117,947	$ 160,023
Trade receivables, net	270,068	257,991
Inventories	93,735	89,043
Prepaid assets	30,198	26,900
Other current assets	47,286	45,297
Total current assets	559,234	579,254
Property, plant and equipment, net	677,959	676,797
Goodwill	438,829	321,077
Intangible assets, net (excluding goodwill)	280,804	178,875
Deferred tax assets	40,028	41,624
Other assets	71,643	72,951
Total assets	2,068,497	1,870,578
Current liabilities:
Current portion of long-term debt and capital leases	17,033	31,904
Accounts payable	36,675	33,815
Accrued compensation	72,832	71,569
Deferred revenue	81,343	78,124
Accrued liabilities	89,494	67,380
Other current liabilities	12,544	9,595
Current liabilities of discontinued operations	1,840	2,299
Total current liabilities	311,761	294,686
Long-term debt, net and capital leases	845,997	740,557
Deferred tax liabilities	48,223	23,087
Other long-term liabilities	89,062	99,545
Long-term liabilities of discontinued operations	7,890	8,357
Total liabilities	$ 1,302,933	$ 1,166,232
Commitments and contingencies
Redeemable noncontrolling interest	$ 28,008	$ 28,419
Equity:
Preferred stock, $0.01 par value; 20,000 shares authorized; no shares issued and outstanding	0	0
Common stock, $0.01 par value; 120,000 shares authorized; 85,464 shares issued and 46,698 shares outstanding at December 26, 2015 and 84,503 shares issued and 47,327 shares outstanding at December 27, 2014	855	845
Additional paid-in capital	2,397,960	2,307,640
Retained earnings (accumulated deficit)	10,538	(138,775)
Treasury stock, at cost, 38,766 shares and 37,176 shares at December 26, 2015 and December 27, 2014, respectively	(1,540,738)	(1,423,260)
Accumulated other comprehensive loss	(135,548)	(74,247)
Total equity attributable to common shareholders	733,067	672,203
Noncontrolling interests	4,489	3,724
Total equity	737,556	675,927
Total liabilities, redeemable noncontrolling interest and equity	2,068,497	1,870,578
Client relationships, net
Current assets:
Intangible assets, net (excluding goodwill)	213,374	161,401
Other intangible assets, net
Current assets:
Intangible assets, net (excluding goodwill)	$ 67,430	$ 17,474

CONSOLIDATED BALANCE SHEETS Bal

CONSOLIDATED BALANCE SHEETS Balance Sheets Parenthetical - $ / shares	Dec. 26, 2015	Dec. 27, 2014
Statement of Financial Position [Abstract]
Preferred Stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	20,000,000	20,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	85,464,000	84,503,000
Common Stock, shares outstanding	46,698,000	47,327,000
Treasury stock, shares	38,766,000	37,176,000

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Cash flows relating to operating activities
Net income	$ 151,087	$ 128,198	$ 104,151
Loss from discontinued operations, net of income taxes	(950)	(1,726)	(1,265)
Income from continuing operations, net of income taxes	152,037	129,924	105,416
Adjustments to reconcile net income from continuing operations to net cash provided by operating activities:
Depreciation and amortization	94,881	96,445	96,636
Amortization of debt issuance costs and discounts	2,380	1,725	9,561
Impairment charges	196	582	4,202
Stock-based compensation	40,122	31,035	24,542
Deferred income taxes	2,689	7,060	(846)
Gain on investments in limited partnerships	(3,823)	(9,301)	(5,864)
Gain on bargain purchase	(9,837)	0	0
Other, net	(28)	(1,564)	755
Changes in assets and liabilities:
Trade receivables, net	(16,963)	(28,088)	(19,492)
Inventories	3,364	(2,956)	(1,571)
Other assets	850	(5,145)	2,421
Accounts payable	1,174	4,599	(7,080)
Accrued compensation	8,414	13,631	11,926
Deferred revenue	6,274	22,244	(3,297)
Accrued liabilities	14,069	8,284	759
Taxes payable and prepaid taxes	(3,906)	(7,090)	(3,054)
Other liabilities	(3,659)	(9,253)	(5,969)
Net cash provided by operating activities	288,234	252,132	209,045
Cash flows relating to investing activities
Acquisition of businesses and assets, net of cash acquired	(247,651)	(234,267)	(29,218)
Capital expenditures	(63,252)	(56,925)	(39,154)
Purchases of investments	(34,235)	(26,648)	(17,566)
Proceeds from sale of investments and distributions from investments in limited partnerships	27,072	21,000	11,584
Other, net	(2,221)	(1,150)	307
Net cash used in investing activities	(320,287)	(297,990)	(74,047)
Cash flows relating to financing activities
Proceeds from long-term debt and revolving credit agreement	492,514	298,920	511,804
Proceeds from exercises of stock options	39,367	73,688	93,789
Payments on long-term debt, capital lease obligations and revolving credit agreement	(417,331)	(194,536)	(523,304)
Purchase of treasury stock	(117,478)	(122,018)	(165,932)
Other, net	7,476	5,360	(594)
Net cash provided by (used in) financing activities	4,548	61,414	(84,237)
Discontinued operations
Net cash used in operating activities from discontinued operations	(1,876)	(1,081)	(1,906)
Effect of exchange rate changes on cash and cash equivalents	(12,695)	(10,379)	(2,613)
Net change in cash and cash equivalents	(42,076)	4,096	46,242
Cash and cash equivalents, beginning of period	160,023	155,927	109,685
Cash and cash equivalents, end of period	117,947	160,023	155,927
Supplemental cash flow information:
Cash paid for income taxes	24,436	29,704	19,139
Cash paid for interest	11,101	10,199	12,029
Non-cash investing and financing activities:
Capitalized interest	424	1,032	243
Additions to property, plant and equipment, net	6,720	4,355	6,960
Assets acquired under capital lease	$ 10,281	$ 18,690	$ 0

CONSOLIDATED STATEMENT OF CHANG

CONSOLIDATED STATEMENT OF CHANGES IN EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common stock	Additional Paid-In Capital	Retained Earnings (Accumulated Deficit)	Accumulated Other Comprehensive Income (Loss)	Treasury Stock	Total Equity Attributable to Common Shareholders	Noncontrolling Interest
Beginning balance at Dec. 29, 2012	$ 603,200	$ 796	$ 2,097,316	$ (368,301)	$ 6,603	$ (1,135,609)	$ 600,805	$ 2,395
Beginning balance, shares at Dec. 29, 2012		79,608				31,388
Increase (Decrease) in Stockholders' Equity
Net income	103,464			102,828			102,828	636
Other comprehensive loss	(1,184)				(1,246)		(1,246)	62
Adjustment of redeemable noncontrolling interest to fair value	(10,564)		(10,564)				(10,564)
Tax benefit associated with stock issued under employee compensation plans	1,069		1,069				1,069
Issuance of stock under employee compensation plans, shares		2,915
Issuance of stock under employee compensation plans	$ 93,821	$ 29	93,792				93,821
Acquisition of treasury shares, shares	100					3,581
Acquisition of treasury shares	$ (170,271)					$ (170,271)	(170,271)
Stock-based compensation	24,542		24,542				24,542
Ending balance, shares at Dec. 28, 2013		82,523				34,969
Ending balance at Dec. 28, 2013	644,077	$ 825	2,206,155	(265,473)	5,357	$ (1,305,880)	640,984	3,093
Increase (Decrease) in Stockholders' Equity
Net income	127,343			126,698			126,698	645
Other comprehensive loss	(79,618)				(79,604)		(79,604)	(14)
Adjustment of redeemable noncontrolling interest to fair value	(7,425)		(7,425)				(7,425)
Tax benefit associated with stock issued under employee compensation plans	4,301		4,301				4,301
Issuance of stock under employee compensation plans, shares		1,980
Issuance of stock under employee compensation plans	$ 73,594	$ 20	73,574				73,594
Acquisition of treasury shares, shares	100					2,207
Acquisition of treasury shares	$ (117,380)					$ (117,380)	(117,380)
Stock-based compensation	$ 31,035		31,035				31,035
Ending balance treasury stock, shares at Dec. 27, 2014	37,176
Ending balance, shares at Dec. 27, 2014		84,503				37,176
Ending balance at Dec. 27, 2014	$ 675,927	$ 845	2,307,640	(138,775)	(74,247)	$ (1,423,260)	672,203	3,724
Increase (Decrease) in Stockholders' Equity
Net income	150,249			149,313			149,313	936
Other comprehensive loss	(61,472)				(61,301)		(61,301)	(171)
Adjustment of redeemable noncontrolling interest to fair value	183		183				183
Tax benefit associated with stock issued under employee compensation plans	10,608		10,608				10,608
Issuance of stock under employee compensation plans, shares		961
Issuance of stock under employee compensation plans	$ 39,417	$ 10	39,407				39,417
Acquisition of treasury shares, shares	100					1,590
Acquisition of treasury shares	$ (117,478)					$ (117,478)	(117,478)
Stock-based compensation	$ 40,122		40,122				40,122
Ending balance treasury stock, shares at Dec. 26, 2015	38,766
Ending balance, shares at Dec. 26, 2015		85,464				38,766
Ending balance at Dec. 26, 2015	$ 737,556	$ 855	$ 2,397,960	$ 10,538	$ (135,548)	$ (1,540,738)	$ 733,067	$ 4,489

Description of Business and Sum

Description of Business and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 26, 2015
Description of Business and Summary of Significant Accounting Policies [Abstract]
DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Description of Business Charles River Laboratories International, Inc. (the Company), together with its subsidiaries, is a full service, early-stage contract research organization (CRO). The Company has built upon its core competency of laboratory animal medicine and science (research model technologies) to develop a diverse portfolio of discovery and safety assessment services, both Good Laboratory Practice (GLP) and non-GLP, which is able to support its clients from target identification through preclinical development. The Company also provides a suite of products and services to support its clients’ manufacturing activities. Principles of Consolidation The Company’s consolidated financial statements reflect its financial statements and those of its subsidiaries in which the Company holds a controlling financial interest. For consolidated entities in which the Company owns or is exposed to less than 100% of the economics, the Company records net income (loss) attributable to noncontrolling interests in its consolidated statements of income equal to the percentage of the economic or ownership interest retained in such entities by the respective noncontrolling parties. Intercompany balances and transactions are eliminated in consolidation. The Company’s fiscal quarters consists of the 3 months ending on the last Saturday on, or prior to, March 31, June 30, September 30 and December 31. Reclassifications Certain reclassifications have been made to prior year statements to conform to the current year presentation. These reclassifications have no impact on period reported net income or cash flow. Segment Reporting During the quarter ended June 28, 2014, following its acquisition of the CRO services division of Galapagos N.V. (Argenta and BioFocus), the Company revised its reportable segments to ensure alignment with the Company’s view of the business. The Company reviewed the new and existing markets addressed by the business, the recently revised go-to-market strategy, long-term operating margins, and the discrete financial information available to its Chief Operating Decision Maker, and considered how its businesses aggregate based on these qualitative and quantitative factors. Based on this review, the Company identified three reportable segments: Research Models and Services (RMS), Discovery and Safety Assessment (DSA) and Manufacturing Support (Manufacturing). The Company reported segment results on this basis for all periods presented. The revised reportable segments are as follows: Research Models and Services Discovery and Safety Assessment Manufacturing Support Research Models Discovery Services (2) Microbial Solutions (formerly Endotoxin and Microbial Detection, or EMD) Research Model Services (1) Safety Assessment Avian Biologics (1) Research Model Services includes Genetically Engineered Models and Services (GEMS), Research Animal Diagnostic Services (RADS), and Insourcing Solutions (IS). (2) Discovery Services includes both the In Vivo Discovery business and the Early Discovery business. Early Discovery includes Argenta and BioFocus, which were acquired in April 2014, ChanTest Corporation (ChanTest), which was acquired in October 2014 and Oncotest GmbH (Oncotest), which was acquired in November 2015. Prior to recasting the reportable segments, the businesses were reported in two segments as follows: Research Models and Services Preclinical Services Research Models (3) Discovery Services Research Model Services (4) Safety Assessment Endotoxin and Microbial Detection Biologics Testing Solutions (3) Research Models included Avian Vaccine Services. (4) Research Model Services included GEMS, RADS, IS and Discovery Research Services. As part of the segment revisions, the former Discovery Research Services was folded into the Company’s Discovery Services business, previously located under the Preclinical Services segment. Use of Estimates The preparation of consolidated financial statements in accordance with generally accepted accounting principles in the United States (U.S. GAAP) requires that the Company makes estimates and judgments that may affect the reported amounts of assets, liabilities, revenues, expenses, and related disclosure of contingent assets and liabilities. On an on-going basis, the Company evaluates its estimates, judgments and methodologies. The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities. Actual results may differ from these estimates under different assumptions or conditions. Changes in estimates are reflected in reported results in the period in which they become known. Cash and Cash Equivalents Cash equivalents include money market funds, time deposits and other investments with remaining maturities at the purchase date of three months or less. Investments Marketable securities are reported at fair value. Realized gains and losses on marketable securities are included in other income (expense), net and are determined using the specific identification method. Unrealized gains and losses on available-for-sale marketable securities are included in accumulated other comprehensive income (loss). Time deposits with original maturities of greater than three months are reported as investments. Trade Receivables, Net The Company records trade receivables net of an allowance for doubtful accounts. An allowance for doubtful accounts is established based on historical collection information, a review of major client accounts receivable balances and current economic conditions in the geographies in which it operates. Amounts determined to be uncollectible are charged or written off against the allowance. Concentrations of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents, investments and trade receivables. The Company places cash and cash equivalents and investments in various financial institutions with high credit rating and limits the amount of credit exposure to any one financial institution. Trade receivables are primarily from clients in the pharmaceutical and biotechnology industries, as well as academic and government institutions. Concentrations of credit risk with respect to trade receivables, which are typically unsecured, are limited due to the wide variety of customers using the Company’s products and services as well as their dispersion across many geographic areas. No single client accounted for more than 5% of revenue or trade receivables for any period presented. Fair Value Measurements The accounting standard for fair value measurements defines fair value, establishes a framework for measuring fair value in accordance with U.S. GAAP, and requires certain disclosures about fair value measurements. Under this standard, fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The Company has certain financial assets and liabilities recorded at fair value which have been classified as Level 1, 2 or 3 within the fair value hierarchy: • Level 1 - Fair values are determined utilizing quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access; • Level 2 - Fair values are determined by utilizing quoted prices for identical or similar assets and liabilities in active markets or other market observable inputs such as interest rates, yield curves and foreign currency spot rates; • Level 3 - Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable. The fair value hierarchy level is determined by asset or liability class based on the lowest level of significant input. The observability of inputs may change for certain assets or liabilities. This condition could cause an asset or liability to be reclassified between levels. The Company recognizes transfers between levels within the fair value hierarchy, if any, at the end of each quarter. Valuation methodologies used for assets and liabilities measured or disclosed at fair value are as follows: • Cash equivalents - Valued at quoted market prices determined through third-party pricing services. • Mutual funds - Valued at the unadjusted quoted net asset value of shares held by the Company. • Foreign currency forward contracts - Valued using readily observable market inputs, such as forward foreign exchange points and foreign exchanges rates. • Life insurance policies - Valued at cash surrender value based on fair value of underlying investments. • Contingent consideration - Valued based on a probability weighting of the future cash flows associated with the potential outcomes. • Redeemable noncontrolling interest - Valued using the income approach based on estimated future cash flows of the underlying business discounted by a weighted average cost of capital. Inventories Inventories are stated at the lower of cost or market. Cost is determined on the average cost method for the small model business and first-in-first-out for the Company’s large model and Microbial Solutions businesses. For the small model business, cost includes direct materials such as feed and bedding, costs of personnel directly involved in the care of the models, and an allocation of facility overhead. For the large model business, cost is primarily the external cost paid to acquire the model. Certain businesses value inventory based on standard costs, which are periodically compared to and adjusted to actual costs. Inventory costs are charged to cost of revenue in the period the products are sold to an external party. The Company analyzes its inventory levels on a quarterly basis and writes down inventory that is determined to be damaged, obsolete or otherwise unmarketable, with a corresponding charge to cost of products sold. Property, Plant and Equipment, Net Property, plant and equipment, including improvements that significantly add to productive capacity or extend useful life, are carried at cost and are subject to review for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. The cost of normal, recurring, or periodic repairs and maintenance activities related to property, plant and equipment is expensed as incurred. In addition, the Company capitalizes certain internal use computer software development costs. Costs incurred during the preliminary project stage are expensed as incurred, while costs incurred during the application development stage are capitalized and amortized over the estimated useful life of the software. The Company also capitalizes costs related to specific upgrades and enhancements when it is probable the expenditures will result in additional functionality. Maintenance and training costs related to software obtained for internal use are expensed as incurred. Interest costs incurred during the construction of major capital projects are capitalized until the underlying asset is ready for its intended use, at which point the interest costs are amortized as depreciation expense over the life of the underlying asset. The Company generally depreciates the cost of its property, plant and equipment using the straight-line method over the estimated useful lives of the respective assets as follows: Estimated (in years) Land Indefinite Buildings 20 - 40 Machinery and equipment 3 - 20 Furniture and fixtures 5 - 10 Computer hardware and software 3 - 8 Vehicles 3 - 5 Leasehold improvements are amortized over the shorter of the estimated useful life of the asset or the lease term. Capital lease assets are amortized over the lease term, however, if ownership is transferred by the end of the capital lease, or there is a bargain purchase option, such capital lease assets are amortized over the useful life that would be assigned if such assets were owned. When the Company disposes of property, plant and equipment, it removes the associated cost and accumulated depreciation from the related accounts on its consolidated balance sheet and includes any resulting gain or loss in its consolidated statement of income. Business Acquisitions The Company accounts for acquisitions as business acquisitions under the acquisition method of accounting. The Company allocates the amounts that it pays for each acquisition to the assets it acquires and liabilities it assumes based on their fair values at the dates of acquisition, including identifiable intangible assets. The Company bases the fair value of identifiable intangible assets acquired in a business combination on valuations that use information and assumptions determined by management and which consider management’s best estimates of inputs and assumptions that a market participant would use. Contingent Consideration The consideration for the Company’s acquisitions often includes future payments that are contingent upon the occurrence of a particular event. The Company records an obligation for such contingent payments at fair value on the acquisition date. The Company estimates the fair value of contingent consideration obligations through valuation models that incorporate probability adjusted assumptions related to the achievement of the milestones and thus likelihood of making related payments. The Company revalues these contingent consideration obligations each reporting period. Changes in the fair value of the contingent consideration obligations are recognized in the Company’s consolidated statements of income as a component of selling, general and administrative expenses. Changes in the fair value of the contingent consideration obligations can result from changes to one or multiple inputs, including adjustments to the discount rates and changes in the assumed probabilities of successful achievement of certain financial targets. Discount rates in the Company’s valuation models represent a measure of the credit risk associated with settling the liability. The period over which the Company discounts its contingent obligations is typically based on when the contingent payments would be triggered. These fair value measurements are based on significant inputs not observable in the market. See Note 5, “Fair Value.” Goodwill and Intangible Assets Goodwill represents the difference between the purchase price and the fair value of the identifiable tangible and intangible net assets when accounted for using the purchase method of accounting. Goodwill is not amortized, but reviewed for impairment on an annual basis, during the fourth quarter, or more frequently if an event occurs or circumstances change that would more-likely-than-not reduce the fair value of the Company's reporting units below their carrying amounts. The Company has the option to first assess qualitative factors to determine whether it is necessary to perform the two-step impairment test. If the Company elects this option and believes, as a result of the qualitative assessment, that it is more-likely-than-not that the carrying value of goodwill is not recoverable, the quantitative two-step impairment test is required; otherwise, no further testing is required. Alternatively, the Company may elect to not first assess qualitative factors and immediately perform the quantitative two-step impairment test. In the first step, the Company compares the fair value of its reporting units to their carrying values. If the carrying values of the net assets assigned to the reporting units exceed the fair values of the reporting units, then the second step of the impairment test is performed in order to determine the implied fair value of the Company’s goodwill. If the carrying value of the reporting unit’s goodwill exceeds its implied fair value, then the Company would record an impairment loss equal to the difference. Definite-lived intangible assets, including client relationships, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets or asset group may not be recoverable. Determination of recoverability is based on an estimate of undiscounted future cash flows resulting from the use of the asset, which requires the use of customer attribution rates and other assumptions. In the event that such cash flows are not expected to be sufficient to recover the carrying amount of the definite-lived intangible assets, the definite-lived intangible assets are written-down to their fair values. Valuation and Impairment of Long-Lived Assets Long-lived assets to be held and used are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets or asset group may not be recoverable. Determination of recoverability is based on an estimate of undiscounted future cash flows resulting from the use of the asset and its eventual disposition. In the event that such cash flows are not expected to be sufficient to recover the carrying amount of the assets, the assets are written-down to their fair values. Long-lived assets to be disposed of are carried at fair value less costs to sell. Limited Partnerships The Company invests in several venture capital limited partnerships that invest in start-up companies primarily in the life sciences industry. The Company ownership interest in these limited partnerships ranges from 3.6% to 12.0% . The Company accounts for such investments under the equity method of accounting, whereby its portion of the investment gains and losses, as reported in the fund’s financial statements on a quarterly lag each reporting period, is recorded in other income (expense), net. In addition, the Company adjusts the carrying value of these investments to reflect its estimate of changes to fair value since the fund’s financial statements based on information from the fund’s management team, market prices of known public holdings of the fund and other information. Life Insurance Contracts Investments in life insurance contracts are recorded at cash surrender value. The initial investment at the transaction price is recognized and remeasured based on fair value of underlying investments or contractual value each reporting period. Investments in and redemptions of these life insurance contracts are reported as cash flows from investing activities in the consolidated statement of cash flows. As of December 26, 2015 and December 27, 2014 , the Company held 42 and 40 contracts, respectively, with a face value of $60.5 million and $68.2 million , respectively. Stock-Based Compensation The Company grants stock options, restricted stock, restricted stock units and performance share units (PSUs) to employees and stock options and restricted stock to non-employee directors under stock-based compensation plans. Stock-based compensation is recognized as an expense in the consolidated financial statements based on the grant date fair value, adjusted for estimated forfeitures, over the requisite service period. For stock options, restricted stock and restricted stock units that vest based on service conditions, the Company uses the straight-line method to allocate compensation expense to reporting periods. Where awards are made with non-substantive vesting periods, where a portion of the award continues to vests after the employee’s retirement, the Company recognizes expense based on the period from the grant date to the date on which the employee is retirement eligible. The Company records the expense for PSU grants subject to performance and/or market conditions using the accelerated attribution method over the remaining service period when management determines that achievement of the performance-based milestone is probable. The fair value of stock options granted is calculated using the Black-Scholes option-pricing model and the fair value of PSUs is estimated using a lattice model with a Monte Carlo simulation, both of which require the use of subjective assumptions including volatility and expected term, among others. The expected volatility assumption is typically determined using the historical volatility of the Company’s common stock over the expected life of the stock-based award. The expected term is determined using historical option exercise activity. The fair value of restricted stock and restricted stock units is based on the market value of the Company’s common stock on the date of grant. Revenue Recognition The Company recognizes revenue when all of the following conditions are satisfied: persuasive evidence of an arrangement exists, delivery has occurred or services have been provided, the price to the customer is fixed or determinable, and collectibility is reasonably assured. Service revenue is generally evidenced by client contracts, which range in duration from a few weeks to a few years and typically take the form of an agreed upon rate per unit or fixed fee arrangements. Such contracts typically do not contain acceptance provisions based upon the achievement of certain study or laboratory testing results. Revenue of agreed upon rate per unit contracts is recognized as services are performed, based upon rates specified in the contract. In cases where performance spans reporting periods, revenue of fixed fee contracts is recognized as services are performed, measured on the ratio of outputs or performance obligations completed to the total contractual outputs or performance obligations to be provided. Changes in estimated effort to complete the fixed fee contract are reflected in the period in which the change becomes known. Changes in scope of work are common, especially under long-term contracts, and generally result in a change in contract value. Once the client has agreed to the changes in scope and renegotiated pricing terms, the contract value is amended and revenue is typically recognized as described above. Billing schedules and payment terms are generally negotiated on a contract-by-contract basis. Payments received in excess of revenue recognized are recorded as deferred revenue. As the contracted services are subsequently performed and the associated revenue is recognized, the deferred revenue balance is reduced by the amount of revenue recognized during the period. In other cases, services may be provided and revenue is recognized before the client is invoiced. In these cases, revenue recognized will exceed amounts billed and the difference, representing amounts which are currently unbillable to the customer pursuant to contractual terms, is recorded as an unbilled receivable. Once the client is invoiced, the unbilled receivable is reduced for the amount billed, and a corresponding trade receivable is recorded. Most contracts are terminable by the client, either immediately or upon notice. These contracts often require payment to the Company of expenses to wind down the project, fees earned to date or, in some cases, a termination fee. Such payments are included in revenues when earned. The Company recognizes product revenue net of allowances for estimated returns, rebates and discounts when title and risk of loss pass to customers. When the Company sells equipment with specified acceptance criteria, it assesses its ability to meet the acceptance criteria in order to determine the timing of revenue recognition. The Company would defer revenue until completion of customer acceptance testing if it is not able to demonstrate the ability to meet such acceptance criteria. A portion of the Company’s revenue is from multiple-element arrangements that include multiple products and/or services as deliverables in a single arrangement with each deliverable, or a combination of the deliverables, representing a separate unit of accounting. The Company allocates revenues to each element in a multiple-element arrangement based upon the relative selling price of each deliverable. Revenue allocated to each deliverable is then recognized when all revenue recognition criteria are met. Judgments as to the identification of deliverables, units of accounting, the allocation of consideration to the deliverable, and the appropriate timing of revenue recognition are critical with respect to these arrangements. At the inception of each arrangement that includes milestone payments, the Company evaluates whether each milestone is substantive. This evaluation includes an assessment of whether (a) the consideration is commensurate with either (1) the Company’s performance to achieve the milestone, or (2) the enhancement of the value of the delivered item(s) as a result of a specific outcome resulting from the Company’s performance to achieve the milestone; (b) the consideration relates solely to past performance; and (c) the consideration is reasonable relative to all of the deliverables and payment terms within the arrangement. If a substantive milestone is achieved and collection of the related receivable is reasonably assured, the Company recognizes revenue related to the milestone in its entirety in the period in which the milestone is achieved. In those circumstances where a milestone is not substantive, the Company recognizes as revenue, on the date the milestone is achieved, an amount equal to the applicable percentage of the performance period that had elapsed as of the date the milestone was achieved, with the balance being deferred and recognized over the remaining period of performance. As of December 26, 2015, the Company had no significant milestones that were deemed substantive. Advertising Costs Advertising costs are expensed as incurred. For the fiscal years 2015 , 2014 and 2013 , advertising costs totaled $1.2 million , $1.3 million and $1.1 million , respectively. Income Taxes The provision for income taxes includes federal, state, local and foreign taxes. Income taxes are accounted for under the liability method. Deferred tax assets and liabilities are recognized for the expected future tax consequences of temporary differences between the financial statements carrying amounts and their respective tax basis. The Company measures deferred tax assets and liabilities using the enacted tax rates expected to be in effect when the temporary differences are expected to be settled. The Company evaluates the realizability of its deferred tax assets and establishes a valuation allowance when it is more likely than not that all or a portion of deferred tax assets will not be realized. The Company accounts for uncertain tax positions using a “more-likely-than-not” threshold for recognizing and resolving uncertain tax positions. The Company evaluates uncertain tax positions on a quarterly basis and considers various factors, including, but not limited to, changes in tax law, the measurement of tax positions taken or expected to be taken in tax returns, the effective settlement of matters subject to audit, information obtained during in process audit activities and changes in facts or circumstances related to a tax position. The Company also accrues for potential interest and penalties related to unrecognized tax benefits in income tax expense. Foreign Currency Contracts Foreign currency contracts are recorded at fair value in the Company’s consolidated balance sheet and are not designated as hedging instruments. Any gains or losses on such contracts are immediately recognized in other income (expense), net. Translation of Foreign Currencies For the Company’s subsidiaries that transact in a functional currency other than the U.S. dollar, assets and liabilities are translated at current rates of exchange at the balance sheet date. Income and expense items are translated at the average foreign exchange rates for the period. Adjustments resulting from the translation of the financial statements of our foreign operations into U.S. dollars are excluded from the determination of net income and are recorded in accumulated other comprehensive income (loss), a separate component of equity. Pension and Other Post-Retirement Benefit Plans The Company recognizes the funded status of its defined benefit pension and other post-retirement benefit plans as an asset or liability. This amount is defined as the difference between the fair value of plan assets and the benefit obligation. The Company measures plan assets and benefit obligations as of its fiscal year end. The key assumptions used to calculate benefit obligations and related pension costs include expected long-term rate of return on plan assets, withdrawal and mortality rates, expected rate of increase in employee compensation levels and discount rate. Assumptions are determined based on the Company’s data and appropriate market indicators, and evaluated each year as of the plan’s measurement date. The expected long-term rate of return on plan assets reflects the average rate of earnings expected on the funds invested, or to be invested, to provide for the benefits included in the projected benefit obligations. In determining the expected long-term rate of return on plan assets, the Company considers the relative weighting of plan assets, the historical performance of total plan assets and individual asset classes and economic and other indicators of future performance. In the fiscal year 2014, for the U.K. and U.S. plans, the Company adopted newly released mortality tables and mortality improvement scales for measurement of retirement plan obligations, which increased the Company’s benefit obligations by $7.9 million as of December 27, 2014. In the fiscal year 2015, new mortality improvement scales were issued in the U.S. and the U.K. reflecting a decline in longevity projection from the 2014 releases that the Company adopted, which decreased the Company’s benefit obligations by $3.3 million as of December 26, 2015. The discount rate reflects the rate the Company would have to pay to purchase high-quality investments that would provide cash sufficient to settle its current pension obligations. Beginning in the fiscal year 2014, the Company had employed a discount rate based on a cash-flow matching analysis using Towers Watson’s proprietary Bond:Link tool. Prior to the fiscal year 2014, the Company employed a cash-flow matching methodology, which used the spot yield curve underlying the Citigroup Index. The refined estimation technique permits the Company to more closely match cash flows to the expected payments to participants than would be possible with the previously used yield curve model. This refinement reduced the Company’s benefit obligations as of December 27, 2014 by $5.5 million . The rate of compensation increase reflects the expected annual salary increases for the plan participants based on historical experience and the current employee compensation strategy. The Company is required to recognize as a component of other comprehensive income, net of tax, the actuarial gains or losses and prior service costs or credits that arise but were not previously required to be recognized as components of net periodic benefit cost. Other comprehensive income is adjusted as these amounts are later recognized in income as components of net periodic benefit cost. Earnings Per Share Basic earnings per share are calculated by dividing net income attributable to common shareholders by the weighted average number of common shares outstanding during the period. Except where the result would be anti-dilutive to income from continuing operations, diluted earnings per share is computed using the treasury stock method, assuming the exercise of stock options and the vesting of restricted stock awards, restricted stock units, or PSUs, as well as their related income tax effects. Newly Adopted Accounting Pronouncements In November 2015, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2015-17, “Balance Sheet Classification of Deferred Taxes,” that requires companies to classify all deferred tax assets and liabilities, along with any valuation allowance, as noncurrent on the balance sheet instead of separating deferred taxes into current and noncurrent amounts. The guidance does not change the existing requirement that only permits offsetting within a jurisdiction. The ASU is effective for fiscal years beginning after December 15, 2016, and interim periods within those fiscal years. Early adoption is permitted. During the fourth quarter of 2015, the Company elected early adoption of this standard as it improved the efficiency of the year end financial

Business Acquisitions

Business Acquisitions	12 Months Ended
	Dec. 26, 2015
Business Combinations [Abstract]
BUSINESS ACQUISITIONS	BUSINESS ACQUISITIONS Oncotest On November 18, 2015, the Company acquired Oncotest, a German CRO providing discovery services for oncology, one of the largest therapeutic areas for biopharmaceutical research and development spending. With this acquisition, the Company has expanded its oncology services capabilities, enabling it to provide clients with access to a more comprehensive portfolio of technologies, including patient-derived xenograft (PDX) and syngeneic models. The purchase price for Oncotest was approximately $ 36.0 million , including $ 0.3 million in contingent consideration. The acquisition was funded by borrowings on the Company's revolving credit facility. The business is reported in the Company’s DSA reportable segment. The contingent consideration is a one-time payment that could become payable based on the achievement of a revenue target for the fiscal year 2016. If achieved, the payment will become due in the first quarter of fiscal year 2017. The aggregate, undiscounted amount of contingent consideration that the Company may pay is €2.0 million ( $2.2 million as of December 26, 2015). The Company estimated the fair value of this contingent consideration based on a probability-weighted set of outcomes. The preliminary purchase price allocation of $35.4 million , net of $ 0.6 million of cash acquired, was as follows: November 18, 2015 (in thousands) Trade receivables (contractual amount of $3,546) $ 3,520 Inventories 129 Other current assets (excluding cash) 706 Property, plant and equipment 2,528 Definite-lived intangible assets 13,330 Goodwill 22,894 Other long-term assets 250 Current liabilities (3,456 ) Long-term liabilities (4,470 ) Total purchase price allocation $ 35,431 The purchase price allocations were prepared on a preliminary basis and are subject to change as additional information becomes available concerning the fair value and tax basis of the assets acquired and liabilities assumed. Any additional adjustments to the purchase price allocation will be made as soon as practicable but no later than one year from the date of acquisition. The breakout of definite-lived intangible assets acquired was as follows: Definite-Lived Intangible Assets Weighted Average Amortization Life (in thousands) (in years) Client relationships $ 7,146 19 Developed technology 5,960 19 Other intangible assets 224 3 Total definite-lived intangible assets $ 13,330 The goodwill resulting from the transaction is primarily attributed to the potential growth in the Company's DSA businesses from customers and technology introduced through Oncotest, the assembled workforce of the acquired business and expected cost synergies. The goodwill attributable to Oncotest is not deductible for tax purposes. The Company incurred transaction and integration costs in connection with the acquisition of $ 2.1 million during the fiscal year 2015 , which were included in selling, general and administrative expenses. Celsis On July 24, 2015, the Company acquired Celsis Group Limited (Celsis), a leading provider of rapid testing systems for non-sterile bacterial contamination for the biopharmaceutical and consumer products industries. The purpose of this acquisition was to enhance the Company’s portfolio of rapid microbial detection products and services with the addition of a rapid bioburden testing product. The purchase price for Celsis was $214.5 million , including assumed debt and certain liabilities of $10.3 million . The acquisition was funded by cash on hand and borrowings on the Company’s revolving credit facility. The business is reported in the Company’s Manufacturing reportable segment. The preliminary purchase price allocation of $ 212.2 million , net of $ 2.3 million of cash acquired, was as follows: July 24, 2015 (in thousands) Trade receivables (contractual amount of $5,410) $ 5,288 Inventories 10,103 Other current assets (excluding cash) 13,432 Property, plant and equipment 4,639 Definite-lived intangible assets 118,140 Goodwill 105,380 Other long-term assets 614 Short-term debt (9,766 ) Other current liabilities (7,448 ) Long-term liabilities (28,146 ) Total purchase price allocation $ 212,236 The purchase price allocations were prepared on a preliminary basis and are subject to change as additional information becomes available concerning the fair value and tax basis of the assets acquired and liabilities assumed. During the fiscal year 2015, the Company recorded measurement-period adjustments related to the Celsis acquisition that resulted in an immaterial change to the purchase price allocation. Any additional adjustments to the purchase price allocation will be made as soon as practicable but no later than one year from the date of acquisition. The breakout of definite-lived intangible assets acquired was as follows: Definite-Lived Intangible Assets Weighted Average Amortization Life (in thousands) (in years) Client relationships $ 71,000 16 Developed technology 39,140 14 Trademark and trade names 5,200 14 Non-compete 2,800 5 Total definite-lived intangible assets $ 118,140 The goodwill resulting from the transaction is primarily attributed to the potential growth of the Company’s Manufacturing business from clients introduced through Celsis, the assembled workforce of the acquired business and expected cost synergies. The goodwill attributable to Celsis is not deductible for tax purposes. The Company incurred transaction and integration costs in connection with the acquisition of $ 8.8 million during the fiscal year 2015 , which were included in selling, general and administrative expenses. Celsis revenue and operating loss for the fiscal year 2015 were $ 11.1 million and $ 6.1 million , respectively. Beginning on July 24, 2015, Celsis has been included in the operating results of the Company. The following selected unaudited pro forma consolidated results of operations are presented as if the Celsis acquisition had occurred as of the beginning of the period immediately preceding the period of acquisition after giving effect to certain nonrecurring costs and other adjustments, resulting in a reversal of $ 0.6 million and additional expenses of $ 13.1 million for the fiscal years 2015 and 2014 , respectively, related to depreciation and amortization of property, plant and equipment, inventory fair value adjustments and intangible assets. Fiscal Year 2015 2014 (in thousands, except per share amounts) (unaudited) Revenue $ 1,380,493 $ 1,329,025 Net income attributable to common shareholders 162,672 110,387 Earnings per common share Basic $ 3.50 $ 2.37 Diluted $ 3.42 $ 2.32 These unaudited pro forma results of operations have been prepared for comparative purposes only, and they do not purport to be indicative of the results of operations that actually would have resulted had the acquisition occurred on the date indicated or that may result in the future. No effect has been given for synergies, if any, that may have been realized through the acquisition. Sunrise On May 5, 2015, the Company acquired Sunrise Farms, Inc. (Sunrise), a producer of specific-pathogen-free fertile chicken eggs and chickens used in the manufacture of live viruses. The purpose of this business acquisition was to expand the capabilities of the Company’s existing Avian Vaccine Services business. The purchase price of the acquisition was $ 9.6 million and was funded by cash on hand and borrowings on the Company’s revolving credit facility. The business is reported in the Company’s Manufacturing reportable segment. The Company recorded a bargain purchase gain of $ 9.8 million , which represents the excess of the estimated fair value of the net assets acquired over the preliminary purchase price. The bargain purchase gain was recorded in other income (expense), net in the Company’s consolidated statement of income and was not recognized for tax purposes. The Company believes there were several factors that contributed to this transaction resulting in a bargain purchase gain, including the highly specialized nature of Sunrise’s business falling outside of the seller’s core activities and a limited pool of potential buyers. Before recognizing the gain from the bargain purchase, the Company reassessed its initial identification and valuation of assets acquired and liabilities assumed to validate that all assets and liabilities that the Company was able to identify at the acquisition date were properly recognized. The preliminary purchase price allocation of $ 9.6 million , net of less than $ 0.1 million of cash acquired, was as follows: May 5, 2015 (in thousands) Trade receivables (contractual amount of $995) $ 981 Inventories 1,518 Other current assets (excluding cash) 973 Property, plant and equipment 13,698 Definite-lived intangible assets 3,400 Current liabilities (925 ) Long-term liabilities (250 ) Fair value of net assets acquired 19,395 Bargain purchase gain (9,837 ) Total purchase price allocation $ 9,558 The purchase price allocations were prepared on a preliminary basis and are subject to change as additional information becomes available concerning the fair value and tax basis of the assets acquired and liabilities assumed. During the fiscal year 2015 , the Company recorded measurement-period adjustments related to the Sunrise acquisition that resulted in an immaterial change to the purchase price allocation and bargain purchase gain. Any additional adjustments to the purchase price allocation will be made as soon as practicable but no later than one year from the date of acquisition. The identifiable definite-lived intangible assets acquired represent the client relationships intangible, which is being amortized over the estimated useful life of approximately 15 years. The Company incurred transaction and integration costs in connection with the acquisition of $ 1.5 million during the fiscal year 2015 , which were included in selling, general and administrative expenses. ChanTest On October 29, 2014, the Company acquired ChanTest, a leading provider of ion channel testing services to the biopharmaceutical industry. The acquisition augments the Company’s early discovery capabilities and enhances the Company’s ability to support clients’ target discovery and lead optimization efforts. The purchase price of the acquisition was $ 59.2 million , including $ 0.3 million in contingent consideration. The business is reported in the Company’s DSA reportable segment. The contingent consideration earn-out period ended in the fourth quarter of 2015. As a result, the related contingent consideration liability was reversed and a gain of $0.3 million was recorded in selling, general and administrative expenses, as no payments are expected to be made. The aggregate, undiscounted amount of contingent consideration that could have become payable was $ 2.0 million . The Company estimated the fair value of this contingent consideration based on a probability-weighted set of outcomes. The purchase price allocation of $ 52.0 million , net of $ 7.2 million in cash acquired, is as follows: October 29, 2014 (in thousands) Current assets (excluding cash) $ 4,669 Property, plant and equipment 1,637 Definite-lived intangible assets 23,920 Goodwill 34,775 Current liabilities (3,486 ) Long-term liabilities (9,486 ) Total purchase price allocation $ 52,029 The breakout of definite-lived intangible assets acquired is as follows: October 29, 2014 Weighted Average Amortization Life (in thousands) (in years) Client relationships $ 19,000 13 Other intangible assets 4,920 9 Total definite-lived intangible assets $ 23,920 The definite-lived intangibles are largely attributed to the expected cash flows related to client relationships existing at the acquisition closing date. The goodwill resulting from the transaction is primarily attributed to the potential growth of the business and is not deductible for tax purposes. The Company incurred insignificant transaction and integration costs in connection with the acquisition during the fiscal year 2015 and costs of $1.1 million during the fiscal year 2014 , which were included in selling, general and administrative expenses. VivoPath On June 16, 2014, the Company acquired substantially all of the assets of VivoPath LLC (VivoPath), a discovery services company specializing in the rapid, in vivo compound evaluation of molecules in the therapeutic areas of metabolism, inflammation and oncology. The purchase price was $ 2.3 million , including $ 1.6 million in contingent consideration, and was allocated primarily to the intangible assets acquired. The Company estimated the fair value of this contingent consideration based on a probability-weighted set of outcomes. The undiscounted total amount of contingent consideration was a maximum of $ 2.4 million , payable over three years based on the achievement of revenue growth targets and other contractual requirements. During the fiscal year 2015 , the Company paid the first year tranche of the contingent consideration of $ 0.6 million and recorded a gain of $ 0.8 million , primarily due to a decrease in the expected future contingent consideration payments. As of December 26, 2015 , the remaining contingent consideration payable is a maximum of $ 0.4 million . The business is reported in the Company’s DSA reportable segment. Argenta and BioFocus On April 1, 2014, the Company acquired (1) 100% of the shares of the United Kingdom (U.K.) based entities Argenta and BioFocus, and (2) certain Dutch assets. These businesses have formed the core of the Company’s Early Discovery business. With this acquisition, the Company has enhanced its position as a full service, early-stage CRO, with integrated in vitro and in vivo capabilities from target discovery through preclinical development. The purchase price of the acquisition was $191.8 million , including $0.9 million in contingent consideration. The acquisition was funded by cash on hand and borrowings on the Company’s revolving credit facility. The businesses are reported in the Company’s DSA reportable segment. The contingent consideration earn-out period ended on April 1, 2015. As a result, the related contingent consideration liability, as adjusted for subsequent changes in fair value, was reversed and a gain of $0.8 million was recorded in selling, general and administrative expenses during the fiscal year 2015 , as no payments are expected to be made. The contingent consideration was a one-time payment that could have become payable in the second quarter of 2015 based on the achievement of a certain revenue target for the twelve-month period following the acquisition. The aggregate, undiscounted amount of contingent consideration that the Company could have paid was € 5.0 million ( $5.5 million as of December 26, 2015 ). The Company estimated the fair value of this contingent consideration based on a probability-weighted set of outcomes. The purchase price allocation of $183.6 million , net of $8.2 million of cash acquired, was as follows: April 1, 2014 (in thousands) Current assets (excluding cash) $ 31,682 Property, plant and equipment 21,008 Other long-term assets 11,140 Definite-lived intangible assets 104,470 Goodwill 65,235 Current liabilities (13,139 ) Long-term liabilities (36,802 ) Total purchase price allocation $ 183,594 The breakout of definite-lived intangible assets acquired was as follows: April 1, 2014 Weighted Average Amortization Life (in thousands) (in years) Client relationships $ 94,000 18 Backlog 5,900 1 Trademark and trade names 1,170 3 Leasehold interests 1,000 13 Other intangible assets 2,400 19 Total definite-lived intangible assets $ 104,470 The goodwill resulting from the transaction is primarily attributed to the potential growth of the Company’s DSA businesses from clients introduced through Argenta and BioFocus, the assembled workforce of the acquired businesses and expected cost synergies. The goodwill attributable to Argenta and BioFocus is not deductible for tax purposes. The Company incurred insignificant transaction and integration costs in connection with the acquisition during the fiscal year 2015 and costs of $5.3 million during the fiscal year 2014 , which were included in selling, general and administrative expenses. Argenta and BioFocus revenue and operating income for the fiscal year 2014 were $71.4 million and $1.8 million , respectively. Beginning on April 1, 2014, Argenta and BioFocus have been included in the operating results of the Company. The following selected unaudited pro forma consolidated results of operations are presented as if the Argenta and BioFocus acquisition had occurred as of the beginning of the period immediately preceding the period of acquisition after giving effect to certain adjustments, including amortization of intangible assets and depreciation of fixed assets of $ 3.7 million and other nonrecurring costs. Fiscal Year 2014 2013 (in thousands, except per share amounts) (unaudited) Revenue $ 1,322,771 $ 1,249,649 Net income attributable to common shareholders 128,195 98,508 Earnings per common share: Basic $ 2.75 $ 2.06 Diluted $ 2.70 $ 2.03 These unaudited pro forma results of operations have been prepared for comparative purposes only, and they do not purport to be indicative of the results of operations that actually would have resulted had the acquisition occurred on the date indicated or that may result in the future. No effect has been given for synergies, if any, that may have been realized through the acquisition. Microbial Solutions Singapore (formerly EMD Singapore) In October 2013, the Company acquired 100% of an Microbial Solutions products and service provider located in Singapore for $4.9 million in cash. The financial results of the acquired entity are included in the Manufacturing reportable segment. The purchase price allocation was as follows: October 4, 2013 (in thousands) Current assets (excluding cash) $ 300 Property, plant and equipment 154 Definite-lived intangible assets 1,885 Goodwill 2,659 Current liabilities (64 ) Total purchase price allocation $ 4,934 The breakout of definite-lived intangible assets acquired was as follows: October 4, 2013 Weighted Average Amortization Life (in thousands) (in years) Client relationships $ 1,870 8 Other intangible assets 15 2 Total definite-lived intangible assets $ 1,885 The goodwill resulting from the transaction is primarily attributed to the potential growth of the business in Southeast Asia and is not deductible for tax purposes. Vital River In January 2013, the Company acquired a 75% ownership interest of Vital River, a commercial provider of research models and related services in China, for $24.2 million , net of $2.7 million of cash acquired. Vital River’s financial results are included in the RMS reportable segment. The purchase price allocation was as follows: January 4, 2013 (in thousands) Current assets (excluding cash) $ 3,092 Property, plant and equipment 10,468 Other long-term assets 2,242 Definite-lived intangible assets 16,954 Goodwill 16,989 Current liabilities (11,303 ) Long-term liabilities (5,260 ) Redeemable noncontrolling interest (8,963 ) Total purchase price allocation $ 24,219 The breakout of definite-lived intangible assets acquired was as follows: January 4, 2013 Weighted Average Amortization Life (in thousands) (in years) Client relationships $ 14,741 12 Reacquired rights 2,053 1 Other intangible assets 160 3 Total definite-lived intangible assets $ 16,954 The goodwill resulting from the transaction is primarily attributed to the potential growth of the business in China and is not deductible for tax purposes. Concurrent with the acquisition, the Company entered into a joint venture agreement with the noncontrolling interest holders that provide the Company with the right to purchase the remaining 25% of the entity for cash at its then appraised value beginning in January 2016. Additionally, the noncontrolling interest holders were granted the right to require the Company to purchase the remaining 25% of the entity at its then appraised value beginning in January 2016 for cash. These rights are accelerated in certain events. As the noncontrolling interest holders can require the Company purchase the remaining 25% interest, the noncontrolling interest is classified in the mezzanine section of the consolidated balance sheet, which is above the equity section and below liabilities. The acquisition-date fair value of the noncontrolling interest was determined based on the fair value of the consideration exchanged for the 75% of Vital River. Subsequent to the acquisition, the noncontrolling interest carrying amount is adjusted to the fair value each quarter using an income approach. The income approach uses estimated future cash flows based on projected financial data discounted by a rate which considers the Company’s weighted average cost of capital and the specific risks of achieving these cash flows. Adjustments to fair value are recorded through additional paid-in capital.

Supplemental Balance Sheet Info

Supplemental Balance Sheet Information	12 Months Ended
	Dec. 26, 2015
Supplemental Balance Sheet Information [Abstract]
SUPPLEMENTAL BALANCE SHEET INFORMATION	SUPPLEMENTAL BALANCE SHEET INFORMATION The composition of trade receivables, net is as follows: December 26, 2015 December 27, 2014 (in thousands) Client receivables $ 230,010 $ 219,118 Unbilled revenue 45,996 43,780 Total 276,006 262,898 Less: Allowance for doubtful accounts (5,938 ) (4,907 ) Trade receivables, net $ 270,068 $ 257,991 Provisions to the allowance for doubtful accounts in the fiscal years 2015 , 2014 and 2013 were $1.8 million , $0.5 million , and $1.3 million , respectively. The composition of inventories is as follows: December 26, 2015 December 27, 2014 (in thousands) Raw materials and supplies $ 15,998 $ 15,416 Work in process 12,101 11,802 Finished products 65,636 61,825 Inventories $ 93,735 $ 89,043 The composition of other current assets is as follows: December 26, 2015 December 27, 2014 (in thousands) Investments $ 20,516 $ 16,167 Prepaid income tax 26,350 26,287 Restricted cash 271 2,552 Other 149 291 Other current assets $ 47,286 $ 45,297 The composition of property, plant and equipment, net is as follows: December 26, 2015 December 27, 2014 (in thousands) Land $ 39,846 $ 40,314 Buildings (1) 713,841 682,495 Machinery and equipment 362,695 384,713 Leasehold improvements 41,477 37,270 Furniture and fixtures 21,783 22,577 Vehicles 3,819 3,967 Computer hardware and software 113,466 119,474 Construction in progress 25,845 40,970 Total 1,322,772 1,331,780 Less: Accumulated depreciation (644,813 ) (654,983 ) Property, plant and equipment, net $ 677,959 $ 676,797 (1) The balance as of December 26, 2015 includes capital lease buildings. See Note 7, “Long-Term Debt and Capital Lease Obligations.” Depreciation expense in the fiscal years 2015 , 2014 and 2013 was $70.7 million , $70.5 million and $78.8 million , respectively. The composition of other assets is as follows: December 26, 2015 December 27, 2014 (in thousands) Life insurance policies $ 27,554 $ 27,603 Investment in limited partnerships 32,730 27,047 Restricted cash 1,745 — Other 9,614 18,301 Other assets $ 71,643 $ 72,951 The composition of other current liabilities is as follows: December 26, 2015 December 27, 2014 (in thousands) Accrued income taxes $ 12,168 $ 9,362 Other 376 233 Other current liabilities $ 12,544 $ 9,595 The composition of other long-term liabilities is as follows: December 26, 2015 December 27, 2014 (in thousands) Long-term pension liability $ 34,604 $ 45,135 Accrued executive supplemental life insurance retirement plan and deferred compensation plan 30,188 33,007 Other 24,270 21,403 Other long-term liabilities $ 89,062 $ 99,545

Investments in Limited Partners

Investments in Limited Partnerships and Marketable Securities (Notes)	12 Months Ended
	Dec. 26, 2015
Marketable Securities and Equity-Method Affiliates [Abstract]
INVESTMENTS IN LIMITED PARTNERSHIPS AND MARKETABLE SECURITIES	INVESTMENTS IN LIMITED PARTNERSHIPS AND MARKETABLE SECURITIES Investments in Limited Partnerships During the fiscal years 2015 , 2014 and 2013 , the Company recognized gains related to the limited partnership investments of $3.8 million , $9.3 million and $5.9 million , respectively. The Company’s total commitment to these entities as of December 26, 2015 was $65.0 million , of which the Company had funded $28.8 million as of December 26, 2015 . During the fiscal years 2015 and 2014 , the Company received dividends totaling $7.3 million and $7.4 million . No distributions were made to the Company in the fiscal year 2013 . As of December 26, 2015 and December 27, 2014 , the Company’s consolidated retained earnings (accumulated deficit) included $2.4 million and $4.6 million , respectively, of the undistributed earnings related to these limited partnerships. Marketable Securities The following is a summary of the Company’s marketable securities, all of which are classified as available-for-sale: December 26, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) Mutual fund $ 4,650 $ — $ (141 ) $ 4,509 Total $ 4,650 $ — $ (141 ) $ 4,509 There were no sales of available-for-sale securities during the fiscal year 2015 .

Fair Value

Fair Value	12 Months Ended
	Dec. 26, 2015
Fair Value Disclosures [Abstract]
FAIR VALUE	FAIR VALUE Assets, liabilities, and redeemable noncontrolling interest measured at fair value on a recurring basis are summarized below: December 26, 2015 Level 1 Level 2 Level 3 Total (in thousands) Cash equivalents $ — $ 190 $ — $ 190 Other current assets: Marketable securities 4,509 — — 4,509 Foreign currency forward contracts — 15 — 15 Other assets: Life insurance policies — 20,364 — 20,364 Total assets measured at fair value $ 4,509 $ 20,569 $ — $ 25,078 Other current liabilities: Contingent consideration $ — $ — $ 1,172 $ 1,172 Other long-term liabilities: Contingent consideration — — 198 198 Redeemable noncontrolling interest — — 28,008 28,008 Total liabilities and redeemable noncontrolling interest measured at fair value $ — $ — $ 29,378 $ 29,378 December 27, 2014 Level 1 Level 2 Level 3 Total (in thousands) Cash equivalents $ — $ 1,934 $ — $ 1,934 Other assets: Life insurance policies — 20,520 — 20,520 Total assets measured at fair value $ — $ 22,454 $ — $ 22,454 Other current liabilities: Contingent consideration $ — $ — $ 1,583 $ 1,583 Other long-term liabilities: Contingent consideration — — 1,245 1,245 Redeemable noncontrolling interest — — 28,419 28,419 Total liabilities and redeemable noncontrolling interest measured at fair value $ — $ — $ 31,247 $ 31,247 During the fiscal years 2015 and 2014 , there were no transfers between fair value levels. Redeemable Noncontrolling Interest The following table provides a rollforward of the fair value of the Company’s redeemable noncontrolling interest related to the acquisition of Vital River in January 2013. Refer to Note 2, “Business Acquisitions.” Fiscal Year 2015 2014 (in thousands) Beginning balance $ 28,419 $ 20,581 Additions — — Total gains or losses (realized/unrealized): Net income attributable to noncontrolling interest 838 855 Foreign currency translation (1,066 ) (442 ) Change in fair value included in additional paid-in capital (183 ) 7,425 Ending balance $ 28,008 $ 28,419 As of December 26, 2015 , the significant unobservable inputs used in the fair value measurement of the Company’s redeemable noncontrolling interest are the estimated future cash flows and a discount rate of 18.0% . Significant changes in the timing or amounts of the estimated future cash flows would result in a significantly higher or lower fair value measurement. Significant increases or decreases in the discount rate would result in a significantly lower or higher fair value measurement, respectively. A 1% increase in the discount rate used would result in a $1.7 million decrease in the fair value of the redeemable noncontrolling interest. Contingent Consideration The following table provides a rollforward of the contingent consideration related to previous business acquisitions. See Note 2, “Business Acquisitions.” Fiscal Year 2015 2014 (in thousands) Beginning balance $ 2,828 $ — Additions 973 2,678 Payments (600 ) — Total gains or losses (realized/unrealized): Reversal of previously recorded contingent liability and change in fair value (1,831 ) 150 Ending balance $ 1,370 $ 2,828 The significant unobservable inputs used in the fair value measurement of the Company’s contingent consideration are the probabilities of successful achievement of certain financial targets and a discount rate. Significant increases or decreases in any of the probabilities of success would result in a significantly higher or lower fair value measurement, respectively. Significant increases or decreases in the discount rate would result in a significantly lower or higher fair value measurement, respectively. Debt Instruments The book value of the Company’s term and revolving loans, which are variable rate loans carried at amortized cost, approximates their fair value based on current market pricing of similar debt. As the fair value is based on significant other observable inputs, including current interest and foreign currency exchange rates, it is deemed to be Level 2.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 26, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND INTANGIBLE ASSETS	GOODWILL AND INTANGIBLE ASSETS Goodwill The following table provides a rollforward of the Company’s goodwill: Adjustments to Goodwill Adjustments to Goodwill December 28, 2013 Acquisitions Transfers Foreign Exchange December 27, 2014 Acquisitions Foreign Exchange December 26, 2015 (in thousands) RMS $ 83,551 $ — $ (23,172 ) $ (1,183 ) $ 59,196 $ — $ (1,029 ) $ 58,167 DSA 1,152,150 102,171 (9,196 ) (10,823 ) 1,234,302 22,146 (4,398 ) 1,252,050 Manufacturing — — 32,368 211 32,579 105,567 (4,534 ) 133,612 Gross carrying amount 1,235,701 1,326,077 1,443,829 DSA - Accumulated impairment loss (1,005,000 ) — — — (1,005,000 ) — — (1,005,000 ) Goodwill $ 230,701 $ 321,077 $ 438,829 In the second quarter of 2014, the Company revised its reportable segments to align with the view of the business following its acquisition of Argenta and BioFocus. See Note 1, "Description of Business and Summary of Significant Accounting Policies." As a result of this reorganization, goodwill was allocated from the Company's prior reportable segments to new reportable segments, as shown in the preceding table within "transfers." The allocation was based on the fair value of each business group within its original reporting unit relative to the fair value of that reporting unit. In addition, the Company completed an assessment of any potential goodwill impairment for all reporting units immediately prior to the reallocation and determined that no impairment existed. Based on the Company’s step one goodwill impairment test for the fiscal years 2015 , 2014 and 2013 , the fair value of each reporting unit exceeded the reporting unit’s book value and, therefore, goodwill was not impaired. Intangible Assets, Net The following table displays the gross carrying amount and accumulated amortization of intangible assets, net by major class: December 26, 2015 December 27, 2014 Gross Accumulated Net Gross Accumulated Net (in thousands) Backlog $ 50,568 $ (50,554 ) $ 14 $ 8,728 $ (6,636 ) $ 2,092 Technology (1) 60,350 (5,911 ) 54,439 13,474 (4,166 ) 9,308 Trademarks and trade names 11,495 (5,944 ) 5,551 6,603 (5,314 ) 1,289 Other identifiable intangible assets 14,711 (7,285 ) 7,426 5,169 (3,822 ) 1,347 Definite-lived other intangible assets, net 137,124 (69,694 ) 67,430 33,974 (19,938 ) 14,036 Indefinite-lived intangibles (1) — 3,438 Total other intangible assets, net 67,430 17,474 Client relationships 396,537 (183,163 ) 213,374 379,339 (217,938 ) 161,401 Total intangible assets, net $ 280,804 $ 178,875 (1) During the fourth quarter of 2015, certain intangible assets with a carrying value of $3.4 million that were previously assigned indefinite lives have been assigned definite lives of 20 years. The Company recorded an immaterial amount of amortization expense on these intangible assets during the fiscal year 2015. Amortization expense of definite-lived intangible assets, including client relationships, for the fiscal years 2015 , 2014 and 2013 was $24.2 million , $26.0 million and $17.8 million , respectively. Estimated amortization expense for intangible assets for each of the next five fiscal years is expected to be as follows: Fiscal Year Amortization Expense (in thousands) 2016 $ 26,835 2017 26,678 2018 24,434 2019 21,617 2020 21,293

Long-Term Debt and Capital Leas

Long-Term Debt and Capital Lease Obligations	12 Months Ended
	Dec. 26, 2015
Debt Disclosure [Abstract]
LONG-TERM DEBT AND CAPITAL LEASE OBLIGATIONS	LONG-TERM DEBT AND CAPITAL LEASE OBLIGATIONS Long-Term Debt Long-term debt, net consists of the following: December 26, 2015 December 27, 2014 (in thousands) Term loans $ 390,000 $ 378,000 Revolving credit facility 446,041 375,536 Other long-term debt 193 214 Total debt 836,234 753,750 Less: current portion of long-term debt (15,193 ) (31,714 ) Long-term debt 821,041 722,036 Debt discount and debt issuance costs (1) (6,805 ) (5,401 ) Long-term debt, net $ 814,236 $ 716,635 (1) During the second quarter of 2015, the Company adopted ASU 2015-03 and reclassified unamortized debt issuance costs from other assets to long-term debt, net and capital leases. See Note 1, “Basis of Presentation” for further discussion. In April 2015, the Company amended and restated the $ 970M Credit Facility, creating a $ 1.3 billion facility ($ 1.3B Credit Facility) that provides for a $ 400.0 million term loan facility and a $ 900.0 million multi-currency revolving facility. The term loan facility matures in 20 quarterly installments with the last installment due April 22, 2020. The revolving facility matures on April 22, 2020 and requires no scheduled payment before that date. The interest rates applicable to term loans and revolving loans under our credit agreement are, at the Company’s option, equal to either the alternate base rate (which is the higher of (1) the prime rate, (2) the federal funds rate plus 0.5% or (3) the one-month adjusted LIBOR rate plus 1% ), or the adjusted LIBOR rate plus an interest rate margin based upon the Company’s leverage ratio. As of December 26, 2015 and December 27, 2014, the weighted average interest rate on the Company’s debt was 1.33% and 1.42% , respectively. The $ 1.3B Credit Facility includes certain customary representations and warranties, events of default, notices of material adverse changes to the Company’s business and negative and affirmative covenants. These covenants include (1) maintenance of a ratio of consolidated earnings before interest, taxes, depreciation and amortization (EBITDA) less capital expenditures to consolidated cash interest expense, for any period of four consecutive fiscal quarters, of no less than 3.5 to 1.0 as well as (2) maintenance of a ratio of consolidated indebtedness to consolidated EBITDA for any period of four consecutive fiscal quarters, of no more than 3.5 to 1.0 . As of December 26, 2015, the Company was compliant with all covenants. The Company’s obligations under the credit agreement are collateralized by substantially all of the Company’s assets. As of December 26, 2015 and December 27, 2014 , the Company had $4.9 million and $5.0 million , respectively, outstanding under letters of credit. Principal maturities of existing debt for the periods set forth in the table below, are as follows: Fiscal Year Principal (in thousands) 2016 $ 15,193 2017 22,500 2018 32,500 2019 50,000 2020 716,041 Total $ 836,234 Capital Lease Obligations The Company acquired a build-to-suit lease as part of its acquisition of Argenta and BioFocus. In accordance with accounting guidance applicable to entities involved with the construction of an asset that will be leased when the construction is completed, the Company was considered the owner, for accounting purposes, of this property during the construction period. Accordingly, the Company recorded an asset and a corresponding financing obligation on its consolidated balance sheet for the amount of total project costs incurred related to the construction in progress for this property through completion of the construction period. Upon completion of the construction during the second quarter of 2015, the Company determined that it was no longer considered the owner of the property because it did not have continuing involvement. Consequently, the Company recorded a successful sale leaseback and derecognized the property and the associated financing obligation from the Company’s consolidated balance sheet and recorded a capital lease asset and a corresponding liability of $ 35.8 million . The Company’s capital lease obligations amounted to $33.6 million and $1.0 million as of December 26, 2015 and December 27, 2014 , respectively.

Equity and Redeemable Noncontro

Equity and Redeemable Noncontrolling Interest	12 Months Ended
	Dec. 26, 2015
Stockholders' Equity Note [Abstract]
EQUITY AND REDEEMABLE NONCONTROLLING INTEREST	EQUITY AND REDEEMABLE NONCONTROLLING INTEREST Earnings Per Share The following table reconciles the numerator and denominator in the computations of basic and diluted earnings per share: Fiscal Year 2015 2014 2013 (in thousands) Numerator: Net income from continuing operations attributable to common shareholders $ 150,263 $ 128,424 $ 104,093 Loss from discontinued operations, net of income taxes (950 ) (1,726 ) (1,265 ) Net income attributable to common shareholders $ 149,313 $ 126,698 $ 102,828 Denominator: Weighted-average shares outstanding—Basic 46,496 46,627 47,740 Effect of dilutive securities: Stock options, restricted stock units, performance share units and restricted stock 1,138 931 749 Weighted-average shares outstanding—Diluted 47,634 47,558 48,489 Options to purchase approximately 0.5 million shares, 0.6 million shares and 2.3 million shares were not included in computing diluted earnings per share for the fiscal years 2015 , 2014 and 2013 , respectively, because their inclusion would have been anti-dilutive. Basic weighted average shares outstanding for the fiscal years 2015 , 2014 and 2013 excluded the impact of approximately 1.1 million shares, 1.2 million shares, and 1.1 million shares, respectively, of non-vested restricted stock, restricted stock units and PSUs. Treasury Shares In July 2010 , the Company’s Board of Directors authorized a $500.0 million stock repurchase program, and subsequently approved increases to the stock repurchase program of $250.0 million in 2010 , $250.0 million in 2013 and $150.0 million in 2014, for an aggregate authorization of $1,150.0 million . The Company repurchased approximately 1.5 million shares for $108.8 million , approximately 2.1 million shares for $ 110.6 million and approximately 3.5 million shares for $ 165.7 million in the fiscal years 2015 , 2014 and 2013 , respectively. As of December 26, 2015 , the Company had $69.7 million remaining on the authorized stock repurchase program. In addition, the Company’s stock-based compensation plans permit the netting of common stock upon vesting of restricted stock, restricted stock units and performance share units in order to satisfy individual minimum statutory tax withholding requirements. The Company repurchased approximately 0.1 million shares for $ 8.7 million , approximately 0.1 million shares for $ 6.8 million and approximately 0.1 million shares for $ 4.6 million in the fiscal years 2015 , 2014 and 2013 , respectively. Accumulated Other Comprehensive Income (Loss) Changes to each component of accumulated other comprehensive income (loss), net of income taxes, are as follows: Foreign Currency Translation and Other (3) Pension and Other Post-Retirement Benefit Plans Total (in thousands) December 28, 2013 $ 28,503 $ (23,146 ) $ 5,357 Other comprehensive loss before reclassifications (1) (48,499 ) (42,236 ) (90,735 ) Amounts reclassified from accumulated other comprehensive income (loss) — 1,234 1,234 Net current period other comprehensive loss (48,499 ) (41,002 ) (89,501 ) Income tax benefit 105 9,792 9,897 December 27, 2014 (19,891 ) (54,356 ) (74,247 ) Other comprehensive loss before reclassifications (2) (60,745 ) (302 ) (61,047 ) Amounts reclassified from accumulated other comprehensive income (loss) (2,341 ) 2,617 276 Net current period other comprehensive (loss) (63,086 ) 2,315 (60,771 ) Income tax expense — (530 ) (530 ) December 26, 2015 $ (82,977 ) $ (52,571 ) $ (135,548 ) (1) The impact of the foreign currency translation adjustment to other comprehensive income (loss) before reclassifications for the fiscal year 2014 was primarily due to the effect of changes in foreign currency exchange rates of the Euro and Canadian Dollar and to a lesser extent due to the impact of changes in the Japanese Yen and British Pound. (2) The impact of the foreign currency translation adjustment to other comprehensive income (loss) before reclassifications for the fiscal year 2015 was primarily due to the effect of changes in foreign currency exchange rates of the Euro and Canadian Dollar and to a lesser extent due to the impact of changes in the British Pound. (3) Foreign currency translation and other includes an insignificant amount of unrealized gains (losses) on available-for-sale marketable securities. Nonredeemable Noncontrolling Interests The Company has investments in several entities, whose financial results are consolidated in the Company’s financial statements, as it has the ability to exercise control over these entities. The interests of the respective noncontrolling parties in these entities have been recorded as noncontrolling interests.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 26, 2015
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES The components of income from continuing operations before income taxes and the related provision for income taxes are presented below: Fiscal Year 2015 2014 2013 (in thousands) Income from continuing operations before income taxes: U.S. $ 76,157 $ 71,002 $ 39,900 Non-U.S. 119,271 106,593 98,427 $ 195,428 $ 177,595 $ 138,327 Income tax provision: Current: Federal 23,687 13,733 10,832 Foreign 8,572 20,364 18,370 State 6,819 4,746 4,240 Total current 39,078 38,843 33,442 Deferred: Federal 1,790 12,982 5,468 Foreign 3,064 (4,672 ) (6,431 ) State (541 ) 518 432 Total deferred 4,313 8,828 (531 ) $ 43,391 $ 47,671 $ 32,911 The components of deferred tax assets and liabilities are as follows: December 26, 2015 December 27, 2014 (in thousands) Deferred tax assets: Compensation $ 55,259 $ 49,702 Accruals and reserves 8,941 7,061 Inventory reserves and valuations 2,022 1,940 Financing related 902 993 Net operating loss and credit carryforwards 35,233 39,927 Other 2,593 4,426 Valuation allowance (6,112 ) (5,866 ) Total deferred tax assets: 98,838 98,183 Deferred tax liabilities: Goodwill and other intangibles (73,208 ) (52,029 ) Depreciation related (23,664 ) (23,549 ) Investments in limited partnerships (3,570 ) (4,067 ) Foreign withholding taxes (6,590 ) — Total deferred tax liabilities: (107,032 ) (79,645 ) Net deferred taxes $ (8,194 ) $ 18,538 Reconciliations of the statutory U.S. Federal income tax rate to effective tax rates are as follows: Fiscal Year 2015 2014 2013 U.S. statutory income tax rate 35.0 % 35.0 % 35.0 % Foreign tax rate differences (8.6 )% (9.4 )% (8.0 )% State income taxes, net of Federal tax benefit 1.9 % 1.9 % 1.6 % Research tax credits and enhanced deductions (2.6 )% (4.1 )% (6.6 )% Enacted tax rate changes (1.5 )% — % (0.4 )% Impact of tax uncertainties (5.2 )% (0.7 )% 1.0 % Foreign withholding taxes 3.4 % — % — % Impact of acquisitions and restructuring (2.0 )% 1.6 % 0.2 % Other 1.8 % 2.5 % 1.0 % 22.2 % 26.8 % 23.8 % The tax rate benefit for the impact of tax uncertainties is primarily related to a $10.4 million reduction in unrecognized tax benefits and related interest due to the expiration of the statute of limitations associated with pre-acquisition tax positions on the forgiveness of debt. The tax rate benefit for enacted tax rate changes is primarily associated with a reduction in the U.K.’s statutory tax rates. The tax benefit associated with a $ 9.8 million non-taxable bargain purchase gain related to the acquisition of Sunrise is included within the impact of acquisitions and restructuring line of the rate reconciliation above. As of December 26, 2015 , the Company had foreign net operating loss and tax credit carryforwards of $34.6 million , as compared to $39.8 million as of December 27, 2014 . Of this amount, $4.3 million will expire beginning after 2015, $18.7 million will begin to expire in 2032 and beyond, and the remainder of $11.6 million can be carried forward indefinitely. In accordance with Canadian Federal tax law, the Company claims Scientific Research and Experimental Development (SR&ED) credits on qualified research and development costs incurred in its Safety Assessment facility in Montreal, and currently maintains $18.7 million in credit carryforwards, which will begin to expire in 2032. Additionally, the Company records a benefit to operating income for research and development credits in both Quebec and the U.K. related to its Safety Assessment and Early Discovery facilities. The Company has fully recognized its deferred tax assets on the belief that it is more likely than not that they will be realized. The only exceptions relate to deferred tax assets primarily for net operating losses in Hong Kong, Luxembourg and the Netherlands, capital losses in the U.S. and Canada, and fixed assets in the U.K. The valuation allowance increased by $0.2 million from $5.9 million as of December 27, 2014 to $6.1 million as of December 26, 2015 . A reconciliation of the Company’s beginning and ending unrecognized income tax benefits is as follows: Fiscal Year 2015 2014 2013 (in thousands) Beginning balance $ 34,627 $ 18,475 $ 30,996 Additions to tax positions for current year 2,362 1,700 2,009 Additions to tax positions for prior years 3,028 18,502 1,709 Reductions to tax positions for current year — — — Reductions to tax positions for prior years (3,991 ) (3,722 ) (732 ) Settlements (1,946 ) (308 ) (15,246 ) Expiration of statute of limitations (10,742 ) (20 ) (261 ) Ending balance $ 23,338 $ 34,627 $ 18,475 The $11.3 million decrease in unrecognized income tax benefits during the fiscal year 2015 is primarily attributable to the expiration of the statute of limitations associated with pre-acquisition tax positions on forgiveness of debt. The amount of unrecognized income tax benefits that, if recognized, would favorably impact the effective tax rate was $ 20.1 million as of December 26, 2015 and $32.3 million as of December 27, 2014. The $12.2 million decrease is primarily attributable to the expiration of the statute of limitations associated with pre-acquisition tax positions on forgiveness of debt. It is reasonably possible as of December 26, 2015 that the liability for unrecognized tax benefits for the uncertain tax position will decrease by $ 1.9 million , primarily as a result of the outcome of a pending tax ruling. The Company continues to recognize interest and penalties related to unrecognized income tax benefits in income tax expense. The total amount of accrued interest related to unrecognized income tax benefits as of December 26, 2015 and December 27, 2014 was $ 1.0 million and $ 1.4 million , respectively. The Company conducts business in a number of tax jurisdictions. As a result, it is subject to tax audits on a regular basis including, but not limited to, such major jurisdictions as the U.S., the U.K., France, Japan, Germany and Canada. With few exceptions, the Company is no longer subject to U.S. and international income tax examinations for years before 2012. The Company and certain of its subsidiaries are currently under audit by various tax authorities in the U.S. and France. The Company does not anticipate resolution of these audits will have a material impact on its financial statements. During 2015, the Company applied with the Internal Revenue Service (IRS) and Canadian Revenue Authority (CRA) for relief pursuant to the competent authority procedure provided in the tax treaty between the U.S. and Canada for transfer pricing tax assessments related to the tax years 2008 through 2012. The Company believes that the controversy will likely be ultimately settled via the competent authority process and accordingly have recorded both a Canadian liability and a U.S. receivable. The actual amounts of the liability for Canadian taxes and the asset for the correlative relief in the U.S. could be different based upon the agreement reached between the IRS and the CRA. On October 21, 2015, the Quebec government enacted Bill 13, which provides for a one-time retroactive benefit to operating income in the fourth quarter of 2015 related to tax years 2012 through 2014 and provides for a corresponding increase to the Company’s effective tax rate. Additionally, the tax law change provides for an ongoing reduction in benefit to operating income and an additional corresponding increase to the Company’s effective tax rate beginning in 2015 and beyond. The cumulative impact of this law change has been reflected in the fourth quarter results. In accordance with the Company’s policy, the undistributed earnings of the Company’s non-U.S. subsidiaries remain indefinitely reinvested outside of the U.S. as of the end of 2015 as they are required to fund needs outside the U.S. and cannot be repatriated in a manner that is substantially tax free. As of December 26, 2015, the earnings of non-U.S. subsidiaries considered to be indefinitely reinvested totaled $547.6 million . No provision for U.S. income taxes has been provided herein. Determination of the amount of unrecognized deferred income tax liabilities on these earnings is not practicable because of the complexities with the hypothetical calculation. Additionally, the amount of liability is dependent on circumstances existing if and when remittance occurs. On December 18, 2015, the U.S. enacted the Consolidated Appropriations Act, which provides for a reinstatement and extension of the controlled foreign corporation look-through rules. This rule allows the Company to access Chinese and Canadian cash in a more tax-efficient manner and utilize the cash outside of the U.S. without triggering residual U.S. tax. As such, in 2015 the Company accrued $6.6 million of foreign withholding taxes to reflect this change.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 26, 2015
Compensation and Retirement Disclosure [Abstract]
EMPLOYEE BENEFIT PLANS	EMPLOYEE BENEFIT PLANS Charles River Laboratories Employee Savings Plan The Charles River Laboratories Employee Savings Plan is a defined contribution plan in the form of a qualified 401(k) plan in which substantially all U.S. employees are eligible to participate upon employment. The plan contains a provision whereby the Company matches a percentage of employee contributions. During the fiscal years 2015 , 2014 and 2013 , the costs associated with this defined contribution plan totaled $5.3 million , $4.9 million and $4.7 million , respectively. Charles River Laboratories Deferred Compensation Plan and Executive Supplemental Life Insurance Retirement Plan The Company maintains a non-qualified deferred compensation plan, known as the Charles River Laboratories Deferred Compensation Plan (DCP), which allows a select group of eligible employees to defer a portion of their compensation. At the present time, no contributions are credited to the DCP, except as set forth below. Participants must specify the distribution date for deferred amounts at the time of deferral, in accordance with applicable IRS regulations. Generally, amounts may be paid in lump sum or installments upon retirement or termination of employment, or later if the employee terminates employment after age 55 and before age 65. Amounts may also be distributed during employment, subject to a minimum deferral requirement of three years. The Company provides certain active employees an annual contribution into their DCP account of 10% of the employee’s base salary plus the lesser of their target annual bonus or actual annual bonus. In addition to the DCP, certain officers and key employees also participate, or in the past participated, in the Company’s Executive Supplemental Life Insurance Retirement Plan (ESLIRP), which is a non-funded, non-qualified arrangement. Annual benefits under this plan will equal a percentage of the highest five consecutive years of compensation, offset by amounts payable under the Charles River Laboratories, Inc. Pension Plan (CRL Pension Plan) and Social Security. In connection with the establishment of the DCP, certain active ESLIRP participants, who agreed to convert their accrued ESLIRP benefit to a comparable deferred compensation benefit, discontinued their direct participation in the ESLIRP. Instead, the present values of the accrued benefits of ESLIRP participants were credited to their DCP accounts, and future accruals are converted to present values and credited to their DCP accounts annually. The costs associated with these plans, including the ESLIRP, for the fiscal years 2015 , 2014 and 2013 totaled $2.6 million , $ 3.3 million and $3.3 million , respectively. The Company has invested in several corporate-owned key-person life insurance policies and mutual funds with the intention of using these investments to fund the ESLIRP and the DCP. Participants have no interest in any such investments. As of December 26, 2015 and December 27, 2014 , the cash surrender value of these life insurance policies were $27.6 million and $27.6 million , respectively. Post-Retirement Health and Life Insurance Plans The Company’s Canadian location offers post-retirement life insurance benefits to its employees and post-retirement medical and dental insurance coverage to certain executives. The plan is non-contributory and unfunded. As of December 26, 2015 and December 27, 2014 , the accumulated benefit obligation related to the plan was $0.9 million and $1.2 million , respectively. The amounts included in other accumulated comprehensive income as well as expenses related to the plan were insignificant in the fiscal years 2015 , 2014 , and 2013 . Pension Plans The CRL Pension Plan is a qualified, non-contributory defined benefit plan covering certain U.S. employees. Effective 2002, the plan was amended to exclude new participants from joining and in 2008 the accrual of benefits was frozen. The Charles River Pension Plan is a defined contribution and defined benefit pension plan covering certain U.K. employees. Benefits are based on participants’ final pensionable salary and years of service. Participants’ rights vest immediately. Effective December 31, 2002, the plan was amended to exclude new participants from joining the defined benefit section of the plan and a defined contribution section was established for new entrants. Contributions under the defined contribution plan are determined as a percentage of gross salary. In the fourth quarter of 2015, the Charles River Pension Plan was amended such that the members of the defined benefit section of the plan will cease to accrue additional benefits; however, their benefits will continue to be adjusted for changes in their final pensionable salary or a specified inflation index, as applicable. In addition, the Company has several defined benefit plans in certain other countries in which it maintains an operating presence, including Japan, Canada and France. The following tables provide a reconciliation of benefit obligations and plan assets of the Company’s pension plans and other post-retirement benefit plans: Pension Plans Other Post-Retirement Benefit Plans December 26, 2015 December 27, 2014 December 26, 2015 December 27, 2014 (in thousands) Change in projected benefit obligations: Benefit obligation at beginning of year $ 326,884 $ 286,212 $ 32,246 $ 29,498 Service cost 3,437 3,397 856 758 Interest cost 11,912 12,822 1,062 1,009 Benefit payments (7,517 ) (9,002 ) (674 ) (722 ) Actuarial loss (gain) (11,783 ) 50,550 1,421 1,703 Administrative expenses paid (411 ) (459 ) — — Effect of foreign exchange (12,213 ) (16,636 ) — — Benefit obligation at end of year $ 310,309 $ 326,884 $ 34,911 $ 32,246 Change in fair value of plan assets: Fair value of plan assets at beginning of year 281,290 272,659 — — Actual return on plan assets 6,263 25,630 — — Employer contributions 6,088 6,874 674 722 Benefit payments (7,517 ) (9,002 ) (674 ) (722 ) Premiums paid (411 ) (459 ) — — Effect of foreign exchange (10,233 ) (14,412 ) — — Fair value of plan assets at end of year $ 275,480 $ 281,290 $ — $ — Net balance sheet liability $ 34,829 $ 45,594 $ 34,911 $ 32,246 Amounts recognized in balance sheet: Noncurrent assets $ 261 $ 61 $ — $ — Current liabilities 149 169 5,984 744 Noncurrent liabilities 34,941 45,486 28,927 31,502 Amounts recognized in accumulated other comprehensive loss: Pension Plans Other Post-Retirement Benefit Plans Fiscal Year Fiscal Year 2015 2014 2015 2014 (in thousands) Net actuarial loss $ 66,499 $ 73,433 $ 6,913 $ 5,761 Net prior service cost (credit) (4,584 ) (5,388 ) — — Net amount recognized $ 61,915 $ 68,045 $ 6,913 $ 5,761 The accumulated benefit obligation and fair value of plan assets for the Company plans with accumulated benefit obligations in excess of plan assets are as follows: Pension Plans Other Post-Retirement Benefit Plans December 26, 2015 December 27, 2014 December 26, 2015 December 27, 2014 (in thousands) Accumulated benefit obligation $ 275,849 $ 299,127 $ 30,584 $ 29,994 Fair value of plan assets 253,225 267,026 — — The projected benefit obligation and fair value of plan assets for the Company plans with projected benefit obligations in excess of plan assets are as follows: Pension Plans Other Post-Retirement Benefit Plans December 26, 2015 December 27, 2014 December 26, 2015 December 27, 2014 (in thousands) Projected benefit obligation $ 301,244 $ 326,731 $ 34,911 $ 32,246 Fair value of plan assets 266,154 281,075 — — The amounts in accumulated other comprehensive income expected to be recognized as components of net periodic benefit cost over the next fiscal year are as follows: Pension Plans Other Post-Retirement Benefit Plans (in thousands) Amortization of net actuarial loss $ 1,931 $ 251 Amortization of net prior service credit (576 ) — Components of net periodic benefit cost: Pension Plans Other Post-Retirement Benefit Plans Fiscal Year Fiscal Year 2015 2014 2013 2015 2014 2013 (in thousands) Service cost $ 3,437 $ 3,397 $ 3,368 $ 856 $ 758 $ 643 Interest cost 11,912 12,822 11,273 1,062 1,009 708 Expected return on plan assets (16,987 ) (17,444 ) (14,672 ) — — — Amortization of prior service cost (credit) (581 ) 961 2,711 — 250 249 Amortization of net loss (gain) 2,929 (637 ) (603 ) 269 660 660 Net periodic cost (benefit) $ 710 $ (901 ) $ 2,077 $ 2,187 $ 2,677 $ 2,260 Assumptions Weighted-average assumptions used to determine projected benefit obligations: Pension Plans Other Post-Retirement Benefit Plans December 26, 2015 December 27, 2014 December 26, 2015 December 27, 2014 Discount rate 3.93 % 3.79 % 3.56 % 3.34 % Rate of compensation increase 3.19 % 3.19 % 3.00 % 3.00 % Weighted-average assumptions used to determine net periodic benefit cost: Pension Plans Other Post-Retirement Benefit Plans December 26, 2015 December 27, 2014 December 28, 2013 December 26, 2015 December 27, 2014 December 28, 2013 Discount rate 3.79 % 4.54 % 4.13 % 3.34 % 3.47 % 2.63 % Expected long-term return on plan assets 6.24 % 6.41 % 6.27 % — — — Rate of compensation increase 3.19 % 3.39 % 3.04 % 3.00 % 3.00 % 2.50 % A 0.5% decrease in the expected rate of return would increase annual pension expense by $1.4 million . Plan assets The Company invests its pension assets with the objective of achieving a total long-term rate of return sufficient to fund future pension obligations and to minimize future pension contributions. The Company is willing to tolerate a commensurate level of risk to achieve this objective. The Company controls its risk by maintaining a diversified portfolio of assets classes. Plan assets did not include any of the Company’s common stock as of December 26, 2015 or December 27, 2014 . The weighted-average target asset allocations are approximately 44.3% to equity securities, approximately 31.1% to fixed income securities and approximately 24.6% to other securities. The fair value of the Company’s pension plan assets by asset category are as follows: December 26, 2015 December 27, 2014 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total (in thousands) Cash $ 92 $ — $ — $ 92 $ 1 $ — $ — $ 1 Equity securities (a) 65,890 5,941 — 71,831 80,692 5,126 — 85,818 Debt securities (b) 68,489 2,822 — 71,311 69,716 3,232 — 72,948 Mutual funds (c) 63,689 65,725 — 129,414 67,079 53,330 — 120,409 Other 1,021 49 1,762 2,832 297 46 1,771 2,114 Total $ 199,181 $ 74,537 $ 1,762 $ 275,480 $ 217,785 $ 61,734 $ 1,771 $ 281,290 (a) This category comprises equity securities held by non-U.S. pension plans valued at the quoted closing price, and translated into U.S. dollars using a foreign currency exchange rate at year end. (b) This category comprises debt securities held by non-U.S. pension plans valued at the quoted closing price, and translated into U.S. dollars using a foreign currency exchange rate at year end. (c) This category comprises mutual funds valued at the net asset value of shares held at year end. The activity within the Level 3 pension plan assets was insignificant during the periods presented. During the fiscal year 2015 , the Company contributed $5.9 million to the pension plans and expects to contribute $4.5 million to its pension plan in 2016 . Expected benefit payments are estimated using the same assumptions used in determining the Company’s benefit obligation as of December 26, 2015 . Benefit payments will depend on future employment and compensation levels, among other factors, and changes in any of these factors could significantly affect these estimated future benefit payments. Estimated future benefit payments during the next five years and in the aggregate for the fiscal years thereafter, are as follows: Pension Plans Other Post-Retirement Benefit Plans (in thousands) 2016 $ 7,561 $ 6,087 2017 7,914 747 2018 8,361 734 2019 8,926 722 2020 9,379 709 Thereafter 52,917 24,480

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 26, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
STOCK-BASED COMPENSATION	STOCK-BASED COMPENSATION The Company has stock-based compensation plans under which employees and non-employee directors may be granted stock-based awards such as stock options, restricted stock, restricted stock units and PSUs. During the fiscal years 2015 , 2014 and 2013 , the primary share-based awards and their general terms and conditions are as follows: • Stock options, which entitle the holder to purchase a specified number of shares of common stock at an exercise price equal to the closing market price of common stock on the date of grant; typically vest over 4 years; and typically expire 5 to 7 years from date of grant. • Restricted stock units, which represent an unsecured promise to grant at no cost a set number of shares of common stock upon the completion of the vesting schedule, and typically vest over 2 to 4 years. With respect to restricted stock units, recipients are not entitled to cash dividends and have no voting rights on the stock during the vesting period. • Restricted stock, which is an award of common stock issued on the grant date and subject to vesting, typically over 2 to 4 years. Recipients cannot sell or transfer the shares until the restriction period has lapsed, but are entitled to forfeitable cash dividends and to vote their respective shares upon grant. • PSUs, which entitle the holder to receive at no cost, a specified number of shares of common stock within a range of shares from zero to a specified maximum and typically vest over 3 years. Payout of this award is contingent upon achievement of certain performance and market conditions. In May 2007, the Company’s shareholders approved the 2007 Incentive Plan, which was amended in 2009, 2011 and 2013 (2007 Plan). The 2007 Plan provided no further awards to be granted under preexisting stock option and incentive plans; provided, however, that any shares that have been forfeited or canceled in accordance with the terms of the applicable award under a preexisting plan may be subsequently awarded in accordance with the terms of the preexisting plan. The 2007 Plan allows a maximum of 18.7 million shares to be awarded, of which restricted stock grants, restricted stock units and performance based stock awards count as 2.3 shares and stock options count as 1.0 shares. Any stock options and other share-based awards that were granted under prior plans and were outstanding in May 2007, continue in accordance with the terms of the respective plans. As of December 26, 2015 , approximately 6.3 million shares were authorized for future grants under the Company’s share-based compensation plans. The Company settles employee share-based compensation awards with newly issued shares. The following table provides the financial statement line items in which stock-based compensation is reflected: Fiscal Year 2015 2014 2013 (in thousands) Cost of revenue (excluding amortization of intangible assets) $ 6,511 $ 5,382 $ 5,381 Selling, general and administrative 33,611 25,653 19,161 Stock-based compensation expense, before income taxes 40,122 31,035 24,542 Provision for income taxes (14,225 ) (11,006 ) (8,658 ) Stock-based compensation, net of income taxes $ 25,897 $ 20,029 $ 15,884 During the fiscal year 2015 , the Company modified certain stock-based awards granted in previous years as part of executive retirement transitions. For the stock-based awards granted to employees during 2015 , the Company introduced a new retirement provision, which allows for continued vesting of such awards after the employee’s retirement if certain eligibility conditions are met. The introduction of the new retirement provision and stock-based award modifications increased the Company’s stock-based compensation expense for 2015 by $4.5 million . The Company capitalized no stock-based compensation related costs for the fiscal years 2015 , 2014 and 2013 . The Company’s pool of excess tax benefits, which is computed in accordance with the long form method, was $22.3 million as of December 26, 2015 , $10.8 million as of December 27, 2014 , and $7.3 million as of December 28, 2013 . During the fiscal year 2015 , the Company recorded a tax benefit of $10.6 million to additional paid-in capital related to the exercise of stock options and vesting of restricted shares and restricted stock units, compared to a tax benefit of $4.3 million in the fiscal year 2014 . The windfall tax benefit reduction of $1.6 million in the fiscal year 2014 , due to the utilization of foreign tax credits, was reversed in the fiscal year 2015 . Stock Options The following table summarizes stock option activities under the Company’s stock-based compensation plans: Number of shares Weighted Average Weighted Average Aggregate (in thousands, except per share amounts) Options outstanding as of December 27, 2014 2,553 $ 43.39 Options granted 474 $ 76.33 Options exercised (909 ) $ 43.34 Options canceled (52 ) $ 55.78 Options outstanding as of December 26, 2015 2,066 $ 50.62 3.7 $ 60,846 Options exercisable as of December 26, 2015 834 $ 37.88 2.6 $ 35,200 Options expected to vest at December 26, 2015 1,219 $ 59.21 4.4 $ 25,448 The fair value of stock options granted was estimated using the Black-Scholes option-pricing model with the following weighted-average assumptions: Fiscal Year 2015 2014 2013 Expected life (in years) 3.6 4.2 4.2 Expected volatility 28 % 30 % 33 % Risk-free interest rate 1.1 % 1.5 % 0.8 % Expected dividend yield 0 % 0 % 0 % The weighted-average grant date fair value of stock options granted was $17.24 , $ 15.19 and $ 11.17 for the fiscal years 2015 , 2014 and 2013 , respectively. As of December 26, 2015 , the unrecognized compensation cost related to unvested stock options expected to vest was $11.2 million . This unrecognized compensation will be recognized over an estimated weighted-average amortization period of 2.2 years . The total intrinsic value of options exercised during the fiscal years 2015 , 2014 and 2013 was $28.3 million , $30.5 million and $24.7 million , respectively, with intrinsic value defined as the difference between the market price on the date of exercise and the exercise price. Restricted Stock and Restricted Stock Units The following table summarizes the restricted stock and restricted stock units activity for the fiscal year 2015 : Restricted Stock and Restricted Stock Units Weighted (in thousands) December 27, 2014 803 $ 44.67 Granted 198 76.16 Vested (365 ) 42.95 Canceled (29 ) 54.08 December 26, 2015 607 $ 55.52 As of December 26, 2015 , the unrecognized compensation cost related to shares of unvested restricted stock and restricted stock units expected to vest was $20.2 million , which is expected to be recognized over an estimated weighted-average amortization period of 1.1 years . The total fair value of restricted stock and restricted stock unit grants that vested during the fiscal years 2015 , 2014 and 2013 was $15.7 million , $13.9 million and $15.1 million , respectively. Performance Based Stock Award Program In the fiscal years 2015 , 2014 and 2013, the Company issued PSUs to certain corporate officers. The number of shares of common stock issued for each PSU is adjusted based on a performance condition linked to the Company’s financial performance. Certain awards are further adjusted based on a market condition, which is calculated based on the Company’s stock performance relative to a peer group over the three-year vesting period. The fair value of the market condition is reflected in the fair value of the award at grant date. The Company utilizes a Monte Carlo simulation valuation model to value these awards. Information pertaining to the Company’s PSUs and the related estimated weighted-average assumptions used to calculate their fair value were as follows: Fiscal Year 2015 2014 2013 PSUs granted 148,900 214,823 163,847 Weighted average per share fair value $88.62 $67.82 $44.47 Key Assumptions: Expected volatility 23 % 29 % 32 % Risk-free interest rate 0.96 % 0.63 % 0.38 % Expected dividend yield — % — % — % 20 trading day average stock price on grant date 20.6 % 13.1 % 6.9 % The maximum amount of common shares to be issued upon vesting of PSUs is approximately 0.8 million . For the fiscal years 2015 , 2014 and 2013 , the Company recognized stock-based compensation related to PSUs of $14.7 million , $8.5 million and $2.2 million , respectively. The total fair value of PSUs that vested during the fiscal year 2015 was $6.6 million . In the fiscal year 2015, the Company also issued approximately 15,000 PSUs using a fair value per share of $76.67 . These PSUs vest upon the achievement of financial targets and other performance measures.

Foreign Currency Contracts

Foreign Currency Contracts	12 Months Ended
	Dec. 26, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
FOREIGN CURRENCY CONTRACTS	FOREIGN CURRENCY CONTRACTS During the fiscal year 2015, the Company entered into foreign exchange forward contracts to limit its foreign currency exposure related to intercompany loans denominated in Euros that are not of a long-term investment nature. These contracts are recorded at fair value in the Company’s consolidated balance sheet and are not designated as hedging instruments. Any gains or losses on such contracts are immediately recognized in other income (expense), net, and are largely offset by the remeasurement of the underlying intercompany loan balances. The notional amount and fair value of the Company’s foreign currency forward contracts is summarized as follows: December 26, 2015 Notional Amount Fair Value Balance Sheet Location (in thousands) $ 88,483 $ 15 Other current assets The following table summarizes the effect of foreign exchange forward contracts on the Company’s consolidated statement of income: Fiscal Year 2015 Location of Gain (Loss) Gain (Loss) Recognized (in thousands) Other income (expense), net $ (4,917 ) The forward contracts outstanding as of December 26, 2015 had durations of approximately 3 months .

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 26, 2015
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Operating Leases The Company rents laboratory and office space, land, vehicles and certain equipment under non-cancelable operating leases. These lease agreements contain various clauses for renewal at the Company’s option and, in certain cases, rent escalation clauses. Rental expense under these leases amounted to $23.4 million , $14.2 million and $16.7 million in the fiscal years 2015 , 2014 and 2013 , respectively. In addition to rent, the leases may require the Company to pay additional amounts for taxes, insurance, maintenance and other operating expenses. As of December 26, 2015 , minimum rental commitments under non-cancelable leases, net of income from subleases, for each of the next five years and total thereafter were as follows: Minimum Lease Payments (in thousands) 2016 $ 19,702 2017 17,841 2018 12,009 2019 9,783 2020 7,969 Thereafter 18,086 Total $ 85,390 Insurance The Company maintains various insurance policies that maintain large deductibles up to approximately $5.0 million , some with or without stop-loss limits, depending on market availability. Insurance policies at certain locations are based on a percentage of the insured assets, for which deductibles for certain property may exceed $5.0 million in the event of a catastrophic event. Litigation Various lawsuits, claims, and proceedings of a nature considered normal to its business are pending against the Company. While the outcome of any of these proceedings cannot be accurately predicted, the Company does not believe the ultimate resolution of any of these existing matters would have a material adverse effect on the Company’s business or financial condition. In July 2015, IDEXX Laboratories, Inc. and IDEXX Distribution, Inc. (collectively, IDEXX) filed a complaint in the United States District Court for the District of Delaware alleging the Company has infringed three recently issued patents related to a blood spot sample collection method used in determining the presence or absence of an infectious disease in a population of rodents. On September 21, 2015, the Company timely filed a motion to dismiss the complaint on the grounds that all of the claims are directed to unpatentable subject matter and therefore are invalid. On October 7, 2015, IDEXX filed an amended complaint which substantially asserts the same patents and infringement allegations as asserted in the original complaint, and on October 26, 2015, the Company timely filed a motion to dismiss this amended complaint. While no prediction may be made as to the outcome of litigation, the Company intends to defend against this proceeding vigorously and therefore an estimate of the possible loss or range of loss cannot be made. In May 2013, the Company commenced an investigation into inaccurate billing with respect to certain government contracts. The Company promptly reported these matters to the relevant government contracting officers, the Department of Health and Human Services’ Office of the Inspector General, and the Department of Justice, and the Company is cooperating with these agencies to ensure the proper repayment and resolution of this matter. The Company has identified approximately $ 1.5 million in excess amounts billed on these contracts since January 1, 2007 and has recorded a liability for such amount as of December 26, 2015 as this represents the Company’s best estimate. Because of the ongoing discussions with the government and the complex nature of this matter, the Company believes it is reasonably possible that additional losses may be incurred but cannot at this time make a reasonable estimate of the potential range of loss beyond such estimated liability. Guarantees The Company enters into certain agreements with other parties in the ordinary course of business that contain indemnification provisions. These typically include agreements with directors and officers, business partners, contractors, landlords, and customers. Under these provisions, the Company generally indemnifies and holds harmless the indemnified party for losses suffered or incurred by the indemnified party as a result of the Company’s activities. These indemnification provisions generally survive termination of the underlying agreement. The maximum potential amount of future payments the Company could be required to make under these indemnification provisions is unlimited. However, to date the Company has not incurred material costs to defend lawsuits or settle claims related to these indemnification provisions. As a result, the estimated fair value of these obligations is minimal.

Segment and Geographic Informat

Segment and Geographic Information	12 Months Ended
	Dec. 26, 2015
Segment Reporting [Abstract]
SEGMENT AND GEOGRAPHIC INFORMATION	SEGMENT AND GEOGRAPHIC INFORMATION The Company revised its reportable segments during the fiscal year 2014 to align with its view of the business following its acquisition of Argenta and BioFocus. See Note 1, “Description of Business and Summary of Significant Accounting Policies.” The Company reported segment results on this basis retrospectively for all comparable prior periods. Asset information on a reportable segment basis is not disclosed as this information is not separately identified and internally reported to the Company’s Chief Operating Decision Maker. The following table presents revenue and other financial information by reportable segment: Fiscal Year 2015 2014 2013 (in thousands) RMS Revenue $ 473,230 $ 507,327 $ 511,350 Operating income 121,447 121,376 116,737 Depreciation and amortization 22,688 27,512 41,837 Capital expenditures 17,398 18,749 16,717 DSA Revenue $ 612,173 $ 538,218 $ 432,378 Operating income 121,981 69,749 47,413 Depreciation and amortization 46,812 47,138 37,720 Capital expenditures 30,333 19,759 12,561 Manufacturing Revenue $ 277,899 $ 252,117 $ 221,800 Operating income 74,201 78,620 61,227 Depreciation and amortization 17,967 14,092 17,079 Capital expenditures 9,814 15,541 9,876 For the fiscal years ended 2015 , 2014 and 2013 , reconciliations of segment operating income and capital expenditures to the respective consolidated amounts are as follows: Operating Income Capital Expenditures Fiscal Year Fiscal Year 2015 2014 2013 2015 2014 2013 (in thousands) Total reportable segments $ 317,629 $ 269,745 $ 225,377 $ 57,545 $ 54,049 $ 39,154 Unallocated corporate (111,180 ) (92,075 ) (73,976 ) 5,707 2,876 — Total consolidated $ 206,449 $ 177,670 $ 151,401 $ 63,252 $ 56,925 $ 39,154 Revenue for each significant product or service offering is as follows : Fiscal Year 2015 2014 2013 (in thousands) RMS $ 473,230 $ 507,327 $ 511,350 DSA 612,173 538,218 432,378 Manufacturing 277,899 252,117 221,800 Total revenue $ 1,363,302 $ 1,297,662 $ 1,165,528 A summary of unallocated corporate overhead consists of the following : Fiscal Year 2015 2014 2013 (in thousands) Stock-based compensation expense $ 25,751 $ 18,474 $ 13,411 Salary, bonus and fringe 33,026 30,838 23,446 Consulting, audit and professional services 15,418 13,431 8,666 IT related expenses 8,400 6,528 11,646 Depreciation expense 7,414 7,703 6,334 Acquisition related adjustments 11,644 6,285 1,752 Other general unallocated corporate expenses 9,527 8,816 8,721 Total unallocated corporate overhead costs $ 111,180 $ 92,075 $ 73,976 Other general unallocated corporate expenses consist of various departmental costs including those associated with departments such as senior executives, corporate accounting, legal, tax, human resources, treasury, and investor relations. Revenue and long-lived assets by geographic area are as follows: U.S. Europe Canada Japan Other Non-U.S. Consolidated (in thousands) 2015 Revenue $ 659,466 $ 435,491 $ 172,349 $ 40,520 $ 55,476 $ 1,363,302 Long-lived assets 402,238 159,445 77,535 22,348 16,393 677,959 2014 Revenue $ 588,531 $ 446,263 $ 163,490 $ 49,921 $ 49,457 $ 1,297,662 Long-lived assets 386,624 153,203 95,272 23,896 17,802 676,797 2013 Revenue $ 551,340 $ 353,688 $ 162,404 $ 59,370 $ 38,726 $ 1,165,528 Long-lived assets 447,829 130,855 109,811 30,589 19,062 738,146 Included in the other non-U.S. category above are operations located in China, Korea, Australia, Singapore and India. Revenues represent sales originating in entities physically located in the identified geographic area. Long-lived assets include property, plant and equipment and other long-lived assets.

Selected Quarterly Financial Da

Selected Quarterly Financial Data (unaudited)	12 Months Ended
	Dec. 26, 2015
Selected Quarterly Financial Data [Abstract]
SELECTED QUARTERLY FINANCIAL DATA (unaudited)	SELECTED QUARTERLY FINANCIAL DATA (unaudited) The following table contains quarterly financial information for fiscal years 2015 and 2014 . The operating results for any quarter are not necessarily indicative of future period results: First Quarter Second Quarter Third Quarter Fourth Quarter Fiscal Year 2015 (in thousands, except per share amounts) Total revenue $ 320,414 $ 339,573 $ 349,465 $ 353,850 Gross profit (1) 119,660 132,783 138,075 140,574 Operating income 43,005 55,735 55,440 52,269 Net income attributable to common shareholders 31,541 48,509 37,379 31,884 Earnings (loss) per common share: Basic: Continuing operations attributable to common shareholders $ 0.67 $ 1.04 $ 0.81 $ 0.71 Discontinued operations — — — (0.02 ) Net income attributable to common shareholders $ 0.67 $ 1.04 $ 0.81 $ 0.69 Diluted: Continuing operations attributable to common shareholders $ 0.66 $ 1.02 $ 0.79 $ 0.69 Discontinued operations — — — (0.02 ) Net income attributable to common shareholders $ 0.66 $ 1.02 $ 0.79 $ 0.67 Fiscal Year 2014 Total revenue $ 299,368 $ 341,179 $ 327,567 $ 329,548 Gross profit (1) 108,813 125,634 118,268 119,945 Operating income 39,706 51,025 46,172 40,767 Net income attributable to common shareholders 32,232 35,264 32,036 27,166 Earnings (loss) per common share: Basic: Continuing operations attributable to common shareholders $ 0.69 $ 0.76 $ 0.70 $ 0.60 Discontinued operations (0.01 ) (0.01 ) — (0.02 ) Net income attributable to common shareholders $ 0.68 $ 0.75 $ 0.70 $ 0.58 Diluted: Continuing operations attributable to common shareholders $ 0.67 $ 0.75 $ 0.68 $ 0.59 Discontinued operations (0.01 ) (0.01 ) — (0.02 ) Net income attributable to common shareholders $ 0.67 $ 0.74 $ 0.68 $ 0.57 (1) Gross profit is calculated as total revenues minus cost of revenue, excluding amortization of intangible assets. Full-year amounts may not sum due to rounding.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 26, 2015
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS On January 6, 2016, the Company entered into a definitive agreement to acquire WRH, Inc. ( WIL Research) for approximately $585.0 million in cash, subject to customary closing adjustments. WIL Research is a premier provider of safety assessment and contract development and manufacturing (CDMO) services to biopharmaceutical and agricultural and industrial chemical companies worldwide. Acquiring WIL Research will enhance the Company’s position as a leading global early-stage CRO by strengthening its ability to partner with global clients across the drug discovery and development continuum. The transaction is expected to close early in the second quarter of 2016, subject to regulatory approvals and customary closing conditions. In connection with the plan to acquire WIL Research, the Company entered into a commitment letter, pursuant to which its existing credit facility will be expanded by up to $350.0 million . In the event the agreement is terminated under specified circumstances, the Company may be required to pay WIL Research a termination fee of $ 17.5 million . WIL Research is expected to be reported primarily as part of the Company’s DSA reportable segment.

Description of Business and S24

Description of Business and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 26, 2015
Description of Business and Summary of Significant Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The Company’s consolidated financial statements reflect its financial statements and those of its subsidiaries in which the Company holds a controlling financial interest. For consolidated entities in which the Company owns or is exposed to less than 100% of the economics, the Company records net income (loss) attributable to noncontrolling interests in its consolidated statements of income equal to the percentage of the economic or ownership interest retained in such entities by the respective noncontrolling parties. Intercompany balances and transactions are eliminated in consolidation. The Company’s fiscal quarters consists of the 3 months ending on the last Saturday on, or prior to, March 31, June 30, September 30 and December 31.
Reclassifications	Reclassifications Certain reclassifications have been made to prior year statements to conform to the current year presentation. These reclassifications have no impact on period reported net income or cash flow.
Segment Reporting	Segment Reporting During the quarter ended June 28, 2014, following its acquisition of the CRO services division of Galapagos N.V. (Argenta and BioFocus), the Company revised its reportable segments to ensure alignment with the Company’s view of the business. The Company reviewed the new and existing markets addressed by the business, the recently revised go-to-market strategy, long-term operating margins, and the discrete financial information available to its Chief Operating Decision Maker, and considered how its businesses aggregate based on these qualitative and quantitative factors. Based on this review, the Company identified three reportable segments: Research Models and Services (RMS), Discovery and Safety Assessment (DSA) and Manufacturing Support (Manufacturing). The Company reported segment results on this basis for all periods presented. The revised reportable segments are as follows: Research Models and Services Discovery and Safety Assessment Manufacturing Support Research Models Discovery Services (2) Microbial Solutions (formerly Endotoxin and Microbial Detection, or EMD) Research Model Services (1) Safety Assessment Avian Biologics (1) Research Model Services includes Genetically Engineered Models and Services (GEMS), Research Animal Diagnostic Services (RADS), and Insourcing Solutions (IS). (2) Discovery Services includes both the In Vivo Discovery business and the Early Discovery business. Early Discovery includes Argenta and BioFocus, which were acquired in April 2014, ChanTest Corporation (ChanTest), which was acquired in October 2014 and Oncotest GmbH (Oncotest), which was acquired in November 2015. Prior to recasting the reportable segments, the businesses were reported in two segments as follows: Research Models and Services Preclinical Services Research Models (3) Discovery Services Research Model Services (4) Safety Assessment Endotoxin and Microbial Detection Biologics Testing Solutions (3) Research Models included Avian Vaccine Services. (4) Research Model Services included GEMS, RADS, IS and Discovery Research Services. As part of the segment revisions, the former Discovery Research Services was folded into the Company’s Discovery Services business, previously located under the Preclinical Services segment.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in accordance with generally accepted accounting principles in the United States (U.S. GAAP) requires that the Company makes estimates and judgments that may affect the reported amounts of assets, liabilities, revenues, expenses, and related disclosure of contingent assets and liabilities. On an on-going basis, the Company evaluates its estimates, judgments and methodologies. The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities. Actual results may differ from these estimates under different assumptions or conditions. Changes in estimates are reflected in reported results in the period in which they become known.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash equivalents include money market funds, time deposits and other investments with remaining maturities at the purchase date of three months or less.
Investments	Investments Marketable securities are reported at fair value. Realized gains and losses on marketable securities are included in other income (expense), net and are determined using the specific identification method. Unrealized gains and losses on available-for-sale marketable securities are included in accumulated other comprehensive income (loss). Time deposits with original maturities of greater than three months are reported as investments.
Trade Receivables, Net	Trade Receivables, Net The Company records trade receivables net of an allowance for doubtful accounts. An allowance for doubtful accounts is established based on historical collection information, a review of major client accounts receivable balances and current economic conditions in the geographies in which it operates. Amounts determined to be uncollectible are charged or written off against the allowance.
Concentrations of Credit Risk	Concentrations of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents, investments and trade receivables. The Company places cash and cash equivalents and investments in various financial institutions with high credit rating and limits the amount of credit exposure to any one financial institution. Trade receivables are primarily from clients in the pharmaceutical and biotechnology industries, as well as academic and government institutions. Concentrations of credit risk with respect to trade receivables, which are typically unsecured, are limited due to the wide variety of customers using the Company’s products and services as well as their dispersion across many geographic areas. No single client accounted for more than 5% of revenue or trade receivables for any period presented.
Fair Value Measurements	Fair Value Measurements The accounting standard for fair value measurements defines fair value, establishes a framework for measuring fair value in accordance with U.S. GAAP, and requires certain disclosures about fair value measurements. Under this standard, fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The Company has certain financial assets and liabilities recorded at fair value which have been classified as Level 1, 2 or 3 within the fair value hierarchy: • Level 1 - Fair values are determined utilizing quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access; • Level 2 - Fair values are determined by utilizing quoted prices for identical or similar assets and liabilities in active markets or other market observable inputs such as interest rates, yield curves and foreign currency spot rates; • Level 3 - Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable. The fair value hierarchy level is determined by asset or liability class based on the lowest level of significant input. The observability of inputs may change for certain assets or liabilities. This condition could cause an asset or liability to be reclassified between levels. The Company recognizes transfers between levels within the fair value hierarchy, if any, at the end of each quarter. Valuation methodologies used for assets and liabilities measured or disclosed at fair value are as follows: • Cash equivalents - Valued at quoted market prices determined through third-party pricing services. • Mutual funds - Valued at the unadjusted quoted net asset value of shares held by the Company. • Foreign currency forward contracts - Valued using readily observable market inputs, such as forward foreign exchange points and foreign exchanges rates. • Life insurance policies - Valued at cash surrender value based on fair value of underlying investments. • Contingent consideration - Valued based on a probability weighting of the future cash flows associated with the potential outcomes. • Redeemable noncontrolling interest - Valued using the income approach based on estimated future cash flows of the underlying business discounted by a weighted average cost of capital.
Inventories	Inventories Inventories are stated at the lower of cost or market. Cost is determined on the average cost method for the small model business and first-in-first-out for the Company’s large model and Microbial Solutions businesses. For the small model business, cost includes direct materials such as feed and bedding, costs of personnel directly involved in the care of the models, and an allocation of facility overhead. For the large model business, cost is primarily the external cost paid to acquire the model. Certain businesses value inventory based on standard costs, which are periodically compared to and adjusted to actual costs. Inventory costs are charged to cost of revenue in the period the products are sold to an external party. The Company analyzes its inventory levels on a quarterly basis and writes down inventory that is determined to be damaged, obsolete or otherwise unmarketable, with a corresponding charge to cost of products sold.
Property, Plant and Equipment, Net	Property, Plant and Equipment, Net Property, plant and equipment, including improvements that significantly add to productive capacity or extend useful life, are carried at cost and are subject to review for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. The cost of normal, recurring, or periodic repairs and maintenance activities related to property, plant and equipment is expensed as incurred. In addition, the Company capitalizes certain internal use computer software development costs. Costs incurred during the preliminary project stage are expensed as incurred, while costs incurred during the application development stage are capitalized and amortized over the estimated useful life of the software. The Company also capitalizes costs related to specific upgrades and enhancements when it is probable the expenditures will result in additional functionality. Maintenance and training costs related to software obtained for internal use are expensed as incurred. Interest costs incurred during the construction of major capital projects are capitalized until the underlying asset is ready for its intended use, at which point the interest costs are amortized as depreciation expense over the life of the underlying asset. The Company generally depreciates the cost of its property, plant and equipment using the straight-line method over the estimated useful lives of the respective assets as follows: Estimated (in years) Land Indefinite Buildings 20 - 40 Machinery and equipment 3 - 20 Furniture and fixtures 5 - 10 Computer hardware and software 3 - 8 Vehicles 3 - 5 Leasehold improvements are amortized over the shorter of the estimated useful life of the asset or the lease term. Capital lease assets are amortized over the lease term, however, if ownership is transferred by the end of the capital lease, or there is a bargain purchase option, such capital lease assets are amortized over the useful life that would be assigned if such assets were owned. When the Company disposes of property, plant and equipment, it removes the associated cost and accumulated depreciation from the related accounts on its consolidated balance sheet and includes any resulting gain or loss in its consolidated statement of income.
Business Combinations	Business Acquisitions The Company accounts for acquisitions as business acquisitions under the acquisition method of accounting. The Company allocates the amounts that it pays for each acquisition to the assets it acquires and liabilities it assumes based on their fair values at the dates of acquisition, including identifiable intangible assets. The Company bases the fair value of identifiable intangible assets acquired in a business combination on valuations that use information and assumptions determined by management and which consider management’s best estimates of inputs and assumptions that a market participant would use. Contingent Consideration The consideration for the Company’s acquisitions often includes future payments that are contingent upon the occurrence of a particular event. The Company records an obligation for such contingent payments at fair value on the acquisition date. The Company estimates the fair value of contingent consideration obligations through valuation models that incorporate probability adjusted assumptions related to the achievement of the milestones and thus likelihood of making related payments. The Company revalues these contingent consideration obligations each reporting period. Changes in the fair value of the contingent consideration obligations are recognized in the Company’s consolidated statements of income as a component of selling, general and administrative expenses. Changes in the fair value of the contingent consideration obligations can result from changes to one or multiple inputs, including adjustments to the discount rates and changes in the assumed probabilities of successful achievement of certain financial targets. Discount rates in the Company’s valuation models represent a measure of the credit risk associated with settling the liability. The period over which the Company discounts its contingent obligations is typically based on when the contingent payments would be triggered. These fair value measurements are based on significant inputs not observable in the market. See Note 5, “Fair Value.”
Goodwill and Intangible Assets	Goodwill and Intangible Assets Goodwill represents the difference between the purchase price and the fair value of the identifiable tangible and intangible net assets when accounted for using the purchase method of accounting. Goodwill is not amortized, but reviewed for impairment on an annual basis, during the fourth quarter, or more frequently if an event occurs or circumstances change that would more-likely-than-not reduce the fair value of the Company's reporting units below their carrying amounts. The Company has the option to first assess qualitative factors to determine whether it is necessary to perform the two-step impairment test. If the Company elects this option and believes, as a result of the qualitative assessment, that it is more-likely-than-not that the carrying value of goodwill is not recoverable, the quantitative two-step impairment test is required; otherwise, no further testing is required. Alternatively, the Company may elect to not first assess qualitative factors and immediately perform the quantitative two-step impairment test. In the first step, the Company compares the fair value of its reporting units to their carrying values. If the carrying values of the net assets assigned to the reporting units exceed the fair values of the reporting units, then the second step of the impairment test is performed in order to determine the implied fair value of the Company’s goodwill. If the carrying value of the reporting unit’s goodwill exceeds its implied fair value, then the Company would record an impairment loss equal to the difference. Definite-lived intangible assets, including client relationships, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets or asset group may not be recoverable. Determination of recoverability is based on an estimate of undiscounted future cash flows resulting from the use of the asset, which requires the use of customer attribution rates and other assumptions. In the event that such cash flows are not expected to be sufficient to recover the carrying amount of the definite-lived intangible assets, the definite-lived intangible assets are written-down to their fair values.
Valuation and Impairment of Long-Lived Assets	Valuation and Impairment of Long-Lived Assets Long-lived assets to be held and used are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets or asset group may not be recoverable. Determination of recoverability is based on an estimate of undiscounted future cash flows resulting from the use of the asset and its eventual disposition. In the event that such cash flows are not expected to be sufficient to recover the carrying amount of the assets, the assets are written-down to their fair values. Long-lived assets to be disposed of are carried at fair value less costs to sell.
Limited Partnerships	Limited Partnerships The Company invests in several venture capital limited partnerships that invest in start-up companies primarily in the life sciences industry. The Company ownership interest in these limited partnerships ranges from 3.6% to 12.0% . The Company accounts for such investments under the equity method of accounting, whereby its portion of the investment gains and losses, as reported in the fund’s financial statements on a quarterly lag each reporting period, is recorded in other income (expense), net. In addition, the Company adjusts the carrying value of these investments to reflect its estimate of changes to fair value since the fund’s financial statements based on information from the fund’s management team, market prices of known public holdings of the fund and other information.
Life Insurance Contracts	Life Insurance Contracts Investments in life insurance contracts are recorded at cash surrender value. The initial investment at the transaction price is recognized and remeasured based on fair value of underlying investments or contractual value each reporting period. Investments in and redemptions of these life insurance contracts are reported as cash flows from investing activities in the consolidated statement of cash flows. As of December 26, 2015 and December 27, 2014 , the Company held 42 and 40 contracts, respectively, with a face value of $60.5 million and $68.2 million , respectively.
Stock-Based Compensation	Stock-Based Compensation The Company grants stock options, restricted stock, restricted stock units and performance share units (PSUs) to employees and stock options and restricted stock to non-employee directors under stock-based compensation plans. Stock-based compensation is recognized as an expense in the consolidated financial statements based on the grant date fair value, adjusted for estimated forfeitures, over the requisite service period. For stock options, restricted stock and restricted stock units that vest based on service conditions, the Company uses the straight-line method to allocate compensation expense to reporting periods. Where awards are made with non-substantive vesting periods, where a portion of the award continues to vests after the employee’s retirement, the Company recognizes expense based on the period from the grant date to the date on which the employee is retirement eligible. The Company records the expense for PSU grants subject to performance and/or market conditions using the accelerated attribution method over the remaining service period when management determines that achievement of the performance-based milestone is probable. The fair value of stock options granted is calculated using the Black-Scholes option-pricing model and the fair value of PSUs is estimated using a lattice model with a Monte Carlo simulation, both of which require the use of subjective assumptions including volatility and expected term, among others. The expected volatility assumption is typically determined using the historical volatility of the Company’s common stock over the expected life of the stock-based award. The expected term is determined using historical option exercise activity. The fair value of restricted stock and restricted stock units is based on the market value of the Company’s common stock on the date of grant.
Revenue Recognition	Revenue Recognition The Company recognizes revenue when all of the following conditions are satisfied: persuasive evidence of an arrangement exists, delivery has occurred or services have been provided, the price to the customer is fixed or determinable, and collectibility is reasonably assured. Service revenue is generally evidenced by client contracts, which range in duration from a few weeks to a few years and typically take the form of an agreed upon rate per unit or fixed fee arrangements. Such contracts typically do not contain acceptance provisions based upon the achievement of certain study or laboratory testing results. Revenue of agreed upon rate per unit contracts is recognized as services are performed, based upon rates specified in the contract. In cases where performance spans reporting periods, revenue of fixed fee contracts is recognized as services are performed, measured on the ratio of outputs or performance obligations completed to the total contractual outputs or performance obligations to be provided. Changes in estimated effort to complete the fixed fee contract are reflected in the period in which the change becomes known. Changes in scope of work are common, especially under long-term contracts, and generally result in a change in contract value. Once the client has agreed to the changes in scope and renegotiated pricing terms, the contract value is amended and revenue is typically recognized as described above. Billing schedules and payment terms are generally negotiated on a contract-by-contract basis. Payments received in excess of revenue recognized are recorded as deferred revenue. As the contracted services are subsequently performed and the associated revenue is recognized, the deferred revenue balance is reduced by the amount of revenue recognized during the period. In other cases, services may be provided and revenue is recognized before the client is invoiced. In these cases, revenue recognized will exceed amounts billed and the difference, representing amounts which are currently unbillable to the customer pursuant to contractual terms, is recorded as an unbilled receivable. Once the client is invoiced, the unbilled receivable is reduced for the amount billed, and a corresponding trade receivable is recorded. Most contracts are terminable by the client, either immediately or upon notice. These contracts often require payment to the Company of expenses to wind down the project, fees earned to date or, in some cases, a termination fee. Such payments are included in revenues when earned. The Company recognizes product revenue net of allowances for estimated returns, rebates and discounts when title and risk of loss pass to customers. When the Company sells equipment with specified acceptance criteria, it assesses its ability to meet the acceptance criteria in order to determine the timing of revenue recognition. The Company would defer revenue until completion of customer acceptance testing if it is not able to demonstrate the ability to meet such acceptance criteria. A portion of the Company’s revenue is from multiple-element arrangements that include multiple products and/or services as deliverables in a single arrangement with each deliverable, or a combination of the deliverables, representing a separate unit of accounting. The Company allocates revenues to each element in a multiple-element arrangement based upon the relative selling price of each deliverable. Revenue allocated to each deliverable is then recognized when all revenue recognition criteria are met. Judgments as to the identification of deliverables, units of accounting, the allocation of consideration to the deliverable, and the appropriate timing of revenue recognition are critical with respect to these arrangements. At the inception of each arrangement that includes milestone payments, the Company evaluates whether each milestone is substantive. This evaluation includes an assessment of whether (a) the consideration is commensurate with either (1) the Company’s performance to achieve the milestone, or (2) the enhancement of the value of the delivered item(s) as a result of a specific outcome resulting from the Company’s performance to achieve the milestone; (b) the consideration relates solely to past performance; and (c) the consideration is reasonable relative to all of the deliverables and payment terms within the arrangement. If a substantive milestone is achieved and collection of the related receivable is reasonably assured, the Company recognizes revenue related to the milestone in its entirety in the period in which the milestone is achieved. In those circumstances where a milestone is not substantive, the Company recognizes as revenue, on the date the milestone is achieved, an amount equal to the applicable percentage of the performance period that had elapsed as of the date the milestone was achieved, with the balance being deferred and recognized over the remaining period of performance.
Advertising Costs	Advertising Costs Advertising costs are expensed as incurred.
Income Taxes	Income Taxes The provision for income taxes includes federal, state, local and foreign taxes. Income taxes are accounted for under the liability method. Deferred tax assets and liabilities are recognized for the expected future tax consequences of temporary differences between the financial statements carrying amounts and their respective tax basis. The Company measures deferred tax assets and liabilities using the enacted tax rates expected to be in effect when the temporary differences are expected to be settled. The Company evaluates the realizability of its deferred tax assets and establishes a valuation allowance when it is more likely than not that all or a portion of deferred tax assets will not be realized. The Company accounts for uncertain tax positions using a “more-likely-than-not” threshold for recognizing and resolving uncertain tax positions. The Company evaluates uncertain tax positions on a quarterly basis and considers various factors, including, but not limited to, changes in tax law, the measurement of tax positions taken or expected to be taken in tax returns, the effective settlement of matters subject to audit, information obtained during in process audit activities and changes in facts or circumstances related to a tax position. The Company also accrues for potential interest and penalties related to unrecognized tax benefits in income tax expense.
Foreign Currency	Foreign Currency Contracts Foreign currency contracts are recorded at fair value in the Company’s consolidated balance sheet and are not designated as hedging instruments. Any gains or losses on such contracts are immediately recognized in other income (expense), net. Translation of Foreign Currencies For the Company’s subsidiaries that transact in a functional currency other than the U.S. dollar, assets and liabilities are translated at current rates of exchange at the balance sheet date. Income and expense items are translated at the average foreign exchange rates for the period. Adjustments resulting from the translation of the financial statements of our foreign operations into U.S. dollars are excluded from the determination of net income and are recorded in accumulated other comprehensive income (loss), a separate component of equity.
Pension and Other Post-Retirement Benefit Plans	Pension and Other Post-Retirement Benefit Plans The Company recognizes the funded status of its defined benefit pension and other post-retirement benefit plans as an asset or liability. This amount is defined as the difference between the fair value of plan assets and the benefit obligation. The Company measures plan assets and benefit obligations as of its fiscal year end. The key assumptions used to calculate benefit obligations and related pension costs include expected long-term rate of return on plan assets, withdrawal and mortality rates, expected rate of increase in employee compensation levels and discount rate. Assumptions are determined based on the Company’s data and appropriate market indicators, and evaluated each year as of the plan’s measurement date. The expected long-term rate of return on plan assets reflects the average rate of earnings expected on the funds invested, or to be invested, to provide for the benefits included in the projected benefit obligations. In determining the expected long-term rate of return on plan assets, the Company considers the relative weighting of plan assets, the historical performance of total plan assets and individual asset classes and economic and other indicators of future performance. In the fiscal year 2014, for the U.K. and U.S. plans, the Company adopted newly released mortality tables and mortality improvement scales for measurement of retirement plan obligations, which increased the Company’s benefit obligations by $7.9 million as of December 27, 2014. In the fiscal year 2015, new mortality improvement scales were issued in the U.S. and the U.K. reflecting a decline in longevity projection from the 2014 releases that the Company adopted, which decreased the Company’s benefit obligations by $3.3 million as of December 26, 2015. The discount rate reflects the rate the Company would have to pay to purchase high-quality investments that would provide cash sufficient to settle its current pension obligations. Beginning in the fiscal year 2014, the Company had employed a discount rate based on a cash-flow matching analysis using Towers Watson’s proprietary Bond:Link tool. Prior to the fiscal year 2014, the Company employed a cash-flow matching methodology, which used the spot yield curve underlying the Citigroup Index. The refined estimation technique permits the Company to more closely match cash flows to the expected payments to participants than would be possible with the previously used yield curve model. This refinement reduced the Company’s benefit obligations as of December 27, 2014 by $5.5 million . The rate of compensation increase reflects the expected annual salary increases for the plan participants based on historical experience and the current employee compensation strategy. The Company is required to recognize as a component of other comprehensive income, net of tax, the actuarial gains or losses and prior service costs or credits that arise but were not previously required to be recognized as components of net periodic benefit cost. Other comprehensive income is adjusted as these amounts are later recognized in income as components of net periodic benefit cost.
Earnings Per Share	Earnings Per Share Basic earnings per share are calculated by dividing net income attributable to common shareholders by the weighted average number of common shares outstanding during the period. Except where the result would be anti-dilutive to income from continuing operations, diluted earnings per share is computed using the treasury stock method, assuming the exercise of stock options and the vesting of restricted stock awards, restricted stock units, or PSUs, as well as their related income tax effects.
New Accounting Pronouncements	. Newly Adopted Accounting Pronouncements In November 2015, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2015-17, “Balance Sheet Classification of Deferred Taxes,” that requires companies to classify all deferred tax assets and liabilities, along with any valuation allowance, as noncurrent on the balance sheet instead of separating deferred taxes into current and noncurrent amounts. The guidance does not change the existing requirement that only permits offsetting within a jurisdiction. The ASU is effective for fiscal years beginning after December 15, 2016, and interim periods within those fiscal years. Early adoption is permitted. During the fourth quarter of 2015, the Company elected early adoption of this standard as it improved the efficiency of the year end financial reporting process for income taxes and applied the changes retrospectively to all prior periods presented in its consolidated financial statements. As of December 27, 2014, the adoption of this standard has resulted in decreases of $27.6 million , $1.5 million , and $7.7 million to other current assets, other current liabilities and noncurrent deferred tax liabilities, respectively, and an increase of $18.4 million to noncurrent deferred tax assets. In September 2015, the FASB issued ASU 2015-16, “Simplifying the Accounting for Measurement-Period Adjustments,” that eliminates the current requirement for an acquirer in a business combination to account for measurement-period adjustments retrospectively. Instead, acquirers will recognize measurement-period adjustments during the period in which they determine the amount of the adjustments, including the effect on earnings of any amounts they would have recorded in previous periods if the accounting had been completed at the acquisition date. The ASU is effective for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. Early adoption is permitted. During the fourth quarter of 2015, the Company elected early adoption of this standard. The adoption of this standard did not have a material impact to the Company’s consolidated financial statements and related disclosures. In April 2015, the FASB issued ASU 2015-04, “Practical Expedient for the Measurement Date of an Employer’s Defined Benefit Obligation and Plan Assets” to provide a practical expedient related to the measurement date of the defined benefit plan assets and obligations. The practical expedient allows employers with fiscal year-end dates that do not coincide with a calendar month end to measure pension and post-retirement benefit plan assets and obligations as of the calendar month-end date closest to the fiscal year end. The standard requires entities that elect the practical expedient to adjust the measurement of benefit plan assets and obligations for contributions or significant events between the month-end measurement date and the entity fiscal year end. The ASU is effective for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. Early adoption is permitted. During the fourth quarter of 2015, the Company elected not to utilize the practical expedient provided by ASU 2015-04. In April 2015, the FASB issued ASU 2015-03, “Simplifying the Presentation of Debt Issuance Costs,” which requires debt issuance costs to be presented in the balance sheet as a direct deduction from the carrying value of the associated debt liability, consistent with the presentation of debt discounts or premiums. The ASU is effective for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. During the second quarter of 2015, the Company elected early adoption of this standard and applied the changes retrospectively to all prior periods presented in its consolidated financial statements. The Company historically presented deferred debt issuance costs, or fees related to directly issuing debt, as assets on the consolidated balance sheets. As of December 27, 2014, the adoption of this standard has resulted in the reclassification of $5.4 million from other assets to long-term debt, net and capital leases. These costs will continue to be amortized as interest expense over the term of the corresponding debt issuance. In February 2015, the FASB issued ASU 2015-02, “Amendments to the Consolidation Analysis,” which amends existing consolidation requirements. The guidance affects reporting entities that are required to evaluate whether they should consolidate certain legal entities. Specifically, the guidance amends (i) the identification of variable interests (fees paid to a decision maker or service provider), (ii) the variable interest entity characteristics for a limited partnership or similar entity and (iii) the primary beneficiary determination. The ASU is effective for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. Early adoption is permitted. During the fourth quarter of 2015, the Company elected early adoption of this standard. The adoption of this standard did not have a material impact to the Company’s consolidated financial statements. Newly Issued Accounting Pronouncements In July 2015, the FASB issued ASU 2015-11, “Simplifying the Measurement of Inventory,” that simplifies the subsequent measurement of inventories by replacing the current lower of cost or market test with a lower of cost or net realizable value test. The ASU is effective for fiscal years beginning after December 15, 2016, and interim periods within those fiscal years. Early adoption is permitted. The Company is still evaluating the impact this standard will have on its consolidated financial statements and related disclosures. In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers.” The standard requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The 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. The standard will be effective for annual and interim periods beginning after December 15, 2017. The Company has not yet selected a transition method and is evaluating the impact the adoption will have on its consolidated financial statements and related disclosures.

Description of Business and S25

Description of Business and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 26, 2015
Description of Business and Summary of Significant Accounting Policies [Abstract]
Property, Plant and Equipment, Useful Lives	The Company generally depreciates the cost of its property, plant and equipment using the straight-line method over the estimated useful lives of the respective assets as follows: Estimated (in years) Land Indefinite Buildings 20 - 40 Machinery and equipment 3 - 20 Furniture and fixtures 5 - 10 Computer hardware and software 3 - 8 Vehicles 3 - 5

Business Acquisitions (Tables)

Business Acquisitions (Tables)	12 Months Ended
	Dec. 26, 2015
Business Acquisition [Line Items]
Schedule of Business Acquisitions, by Acquisition	The preliminary purchase price allocation of $ 212.2 million , net of $ 2.3 million of cash acquired, was as follows: July 24, 2015 (in thousands) Trade receivables (contractual amount of $5,410) $ 5,288 Inventories 10,103 Other current assets (excluding cash) 13,432 Property, plant and equipment 4,639 Definite-lived intangible assets 118,140 Goodwill 105,380 Other long-term assets 614 Short-term debt (9,766 ) Other current liabilities (7,448 ) Long-term liabilities (28,146 ) Total purchase price allocation $ 212,236 The preliminary purchase price allocation of $ 9.6 million , net of less than $ 0.1 million of cash acquired, was as follows: May 5, 2015 (in thousands) Trade receivables (contractual amount of $995) $ 981 Inventories 1,518 Other current assets (excluding cash) 973 Property, plant and equipment 13,698 Definite-lived intangible assets 3,400 Current liabilities (925 ) Long-term liabilities (250 ) Fair value of net assets acquired 19,395 Bargain purchase gain (9,837 ) Total purchase price allocation $ 9,558 The preliminary purchase price allocation of $35.4 million , net of $ 0.6 million of cash acquired, was as follows: November 18, 2015 (in thousands) Trade receivables (contractual amount of $3,546) $ 3,520 Inventories 129 Other current assets (excluding cash) 706 Property, plant and equipment 2,528 Definite-lived intangible assets 13,330 Goodwill 22,894 Other long-term assets 250 Current liabilities (3,456 ) Long-term liabilities (4,470 ) Total purchase price allocation $ 35,431
Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination	The breakout of definite-lived intangible assets acquired was as follows: Definite-Lived Intangible Assets Weighted Average Amortization Life (in thousands) (in years) Client relationships $ 71,000 16 Developed technology 39,140 14 Trademark and trade names 5,200 14 Non-compete 2,800 5 Total definite-lived intangible assets $ 118,140 The breakout of definite-lived intangible assets acquired was as follows: Definite-Lived Intangible Assets Weighted Average Amortization Life (in thousands) (in years) Client relationships $ 7,146 19 Developed technology 5,960 19 Other intangible assets 224 3 Total definite-lived intangible assets $ 13,330
Business Acquisition, Pro Forma Information	The following selected unaudited pro forma consolidated results of operations are presented as if the Celsis acquisition had occurred as of the beginning of the period immediately preceding the period of acquisition after giving effect to certain nonrecurring costs and other adjustments, resulting in a reversal of $ 0.6 million and additional expenses of $ 13.1 million for the fiscal years 2015 and 2014 , respectively, related to depreciation and amortization of property, plant and equipment, inventory fair value adjustments and intangible assets. Fiscal Year 2015 2014 (in thousands, except per share amounts) (unaudited) Revenue $ 1,380,493 $ 1,329,025 Net income attributable to common shareholders 162,672 110,387 Earnings per common share Basic $ 3.50 $ 2.37 Diluted $ 3.42 $ 2.32
ChanTest
Business Acquisition [Line Items]
Schedule of Business Acquisitions, by Acquisition	The purchase price allocation of $ 52.0 million , net of $ 7.2 million in cash acquired, is as follows: October 29, 2014 (in thousands) Current assets (excluding cash) $ 4,669 Property, plant and equipment 1,637 Definite-lived intangible assets 23,920 Goodwill 34,775 Current liabilities (3,486 ) Long-term liabilities (9,486 ) Total purchase price allocation $ 52,029
Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination	The breakout of definite-lived intangible assets acquired is as follows: October 29, 2014 Weighted Average Amortization Life (in thousands) (in years) Client relationships $ 19,000 13 Other intangible assets 4,920 9 Total definite-lived intangible assets $ 23,920
Early Discovery UK
Business Acquisition [Line Items]
Schedule of Business Acquisitions, by Acquisition	The purchase price allocation of $183.6 million , net of $8.2 million of cash acquired, was as follows: April 1, 2014 (in thousands) Current assets (excluding cash) $ 31,682 Property, plant and equipment 21,008 Other long-term assets 11,140 Definite-lived intangible assets 104,470 Goodwill 65,235 Current liabilities (13,139 ) Long-term liabilities (36,802 ) Total purchase price allocation $ 183,594
Business Acquisition, Pro Forma Information	The following selected unaudited pro forma consolidated results of operations are presented as if the Argenta and BioFocus acquisition had occurred as of the beginning of the period immediately preceding the period of acquisition after giving effect to certain adjustments, including amortization of intangible assets and depreciation of fixed assets of $ 3.7 million and other nonrecurring costs. Fiscal Year 2014 2013 (in thousands, except per share amounts) (unaudited) Revenue $ 1,322,771 $ 1,249,649 Net income attributable to common shareholders 128,195 98,508 Earnings per common share: Basic $ 2.75 $ 2.06 Diluted $ 2.70 $ 2.03
Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination	The breakout of definite-lived intangible assets acquired was as follows: April 1, 2014 Weighted Average Amortization Life (in thousands) (in years) Client relationships $ 94,000 18 Backlog 5,900 1 Trademark and trade names 1,170 3 Leasehold interests 1,000 13 Other intangible assets 2,400 19 Total definite-lived intangible assets $ 104,470
Microbial Solutions
Business Acquisition [Line Items]
Schedule of Business Acquisitions, by Acquisition	The purchase price allocation was as follows: October 4, 2013 (in thousands) Current assets (excluding cash) $ 300 Property, plant and equipment 154 Definite-lived intangible assets 1,885 Goodwill 2,659 Current liabilities (64 ) Total purchase price allocation $ 4,934
Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination	The breakout of definite-lived intangible assets acquired was as follows: October 4, 2013 Weighted Average Amortization Life (in thousands) (in years) Client relationships $ 1,870 8 Other intangible assets 15 2 Total definite-lived intangible assets $ 1,885
Vital River
Business Acquisition [Line Items]
Schedule of Business Acquisitions, by Acquisition	The purchase price allocation was as follows: January 4, 2013 (in thousands) Current assets (excluding cash) $ 3,092 Property, plant and equipment 10,468 Other long-term assets 2,242 Definite-lived intangible assets 16,954 Goodwill 16,989 Current liabilities (11,303 ) Long-term liabilities (5,260 ) Redeemable noncontrolling interest (8,963 ) Total purchase price allocation $ 24,219
Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination	The breakout of definite-lived intangible assets acquired was as follows: January 4, 2013 Weighted Average Amortization Life (in thousands) (in years) Client relationships $ 14,741 12 Reacquired rights 2,053 1 Other intangible assets 160 3 Total definite-lived intangible assets $ 16,954

Supplemental Balance Sheet In27

Supplemental Balance Sheet Information (Tables)	12 Months Ended
	Dec. 26, 2015
Supplemental Balance Sheet Information [Abstract]
Composition of Trade Receivables	The composition of trade receivables, net is as follows: December 26, 2015 December 27, 2014 (in thousands) Client receivables $ 230,010 $ 219,118 Unbilled revenue 45,996 43,780 Total 276,006 262,898 Less: Allowance for doubtful accounts (5,938 ) (4,907 ) Trade receivables, net $ 270,068 $ 257,991
Composition of Inventory	The composition of inventories is as follows: December 26, 2015 December 27, 2014 (in thousands) Raw materials and supplies $ 15,998 $ 15,416 Work in process 12,101 11,802 Finished products 65,636 61,825 Inventories $ 93,735 $ 89,043
Composition of Other Current Assets	The composition of other current assets is as follows: December 26, 2015 December 27, 2014 (in thousands) Investments $ 20,516 $ 16,167 Prepaid income tax 26,350 26,287 Restricted cash 271 2,552 Other 149 291 Other current assets $ 47,286 $ 45,297
Composition of Property, Plant and Equipment, Net	The composition of property, plant and equipment, net is as follows: December 26, 2015 December 27, 2014 (in thousands) Land $ 39,846 $ 40,314 Buildings (1) 713,841 682,495 Machinery and equipment 362,695 384,713 Leasehold improvements 41,477 37,270 Furniture and fixtures 21,783 22,577 Vehicles 3,819 3,967 Computer hardware and software 113,466 119,474 Construction in progress 25,845 40,970 Total 1,322,772 1,331,780 Less: Accumulated depreciation (644,813 ) (654,983 ) Property, plant and equipment, net $ 677,959 $ 676,797 (1) The balance as of December 26, 2015 includes capital lease buildings. See Note 7, “Long-Term Debt and Capital Lease Obligations.”
Composition of Other Assets	The composition of other assets is as follows: December 26, 2015 December 27, 2014 (in thousands) Life insurance policies $ 27,554 $ 27,603 Investment in limited partnerships 32,730 27,047 Restricted cash 1,745 — Other 9,614 18,301 Other assets $ 71,643 $ 72,951
Composition of Other Current Liabilities	The composition of other current liabilities is as follows: December 26, 2015 December 27, 2014 (in thousands) Accrued income taxes $ 12,168 $ 9,362 Other 376 233 Other current liabilities $ 12,544 $ 9,595
Schedule of Other Liabilities	The composition of other long-term liabilities is as follows: December 26, 2015 December 27, 2014 (in thousands) Long-term pension liability $ 34,604 $ 45,135 Accrued executive supplemental life insurance retirement plan and deferred compensation plan 30,188 33,007 Other 24,270 21,403 Other long-term liabilities $ 89,062 $ 99,545

Investments in Limited Partne28

Investments in Limited Partnerships and Marketable Securities (Tables)	12 Months Ended
	Dec. 26, 2015
Marketable Securities and Equity-Method Affiliates [Abstract]
Schedule of Available-for-sale Securities Reconciliation	The following is a summary of the Company’s marketable securities, all of which are classified as available-for-sale: December 26, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) Mutual fund $ 4,650 $ — $ (141 ) $ 4,509 Total $ 4,650 $ — $ (141 ) $ 4,509

Fair Value (Tables)

Fair Value (Tables)	12 Months Ended
	Dec. 26, 2015
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	Assets, liabilities, and redeemable noncontrolling interest measured at fair value on a recurring basis are summarized below: December 26, 2015 Level 1 Level 2 Level 3 Total (in thousands) Cash equivalents $ — $ 190 $ — $ 190 Other current assets: Marketable securities 4,509 — — 4,509 Foreign currency forward contracts — 15 — 15 Other assets: Life insurance policies — 20,364 — 20,364 Total assets measured at fair value $ 4,509 $ 20,569 $ — $ 25,078 Other current liabilities: Contingent consideration $ — $ — $ 1,172 $ 1,172 Other long-term liabilities: Contingent consideration — — 198 198 Redeemable noncontrolling interest — — 28,008 28,008 Total liabilities and redeemable noncontrolling interest measured at fair value $ — $ — $ 29,378 $ 29,378 December 27, 2014 Level 1 Level 2 Level 3 Total (in thousands) Cash equivalents $ — $ 1,934 $ — $ 1,934 Other assets: Life insurance policies — 20,520 — 20,520 Total assets measured at fair value $ — $ 22,454 $ — $ 22,454 Other current liabilities: Contingent consideration $ — $ — $ 1,583 $ 1,583 Other long-term liabilities: Contingent consideration — — 1,245 1,245 Redeemable noncontrolling interest — — 28,419 28,419 Total liabilities and redeemable noncontrolling interest measured at fair value $ — $ — $ 31,247 $ 31,247
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation	The following table provides a rollforward of the fair value of the Company’s redeemable noncontrolling interest related to the acquisition of Vital River in January 2013. Refer to Note 2, “Business Acquisitions.” Fiscal Year 2015 2014 (in thousands) Beginning balance $ 28,419 $ 20,581 Additions — — Total gains or losses (realized/unrealized): Net income attributable to noncontrolling interest 838 855 Foreign currency translation (1,066 ) (442 ) Change in fair value included in additional paid-in capital (183 ) 7,425 Ending balance $ 28,008 $ 28,419 As of December 26, 2015 , the significant unobservable inputs used in the fair value measurement of the Company’s redeemable noncontrolling interest are the estimated future cash flows and a discount rate of 18.0% . Significant changes in the timing or amounts of the estimated future cash flows would result in a significantly higher or lower fair value measurement. Significant increases or decreases in the discount rate would result in a significantly lower or higher fair value measurement, respectively. A 1% increase in the discount rate used would result in a $1.7 million decrease in the fair value of the redeemable noncontrolling interest. Contingent Consideration The following table provides a rollforward of the contingent consideration related to previous business acquisitions. See Note 2, “Business Acquisitions.” Fiscal Year 2015 2014 (in thousands) Beginning balance $ 2,828 $ — Additions 973 2,678 Payments (600 ) — Total gains or losses (realized/unrealized): Reversal of previously recorded contingent liability and change in fair value (1,831 ) 150 Ending balance $ 1,370 $ 2,828

Goodwill and Other Intangible30

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 26, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Intangible Assets and Goodwill	The following table provides a rollforward of the Company’s goodwill: Adjustments to Goodwill Adjustments to Goodwill December 28, 2013 Acquisitions Transfers Foreign Exchange December 27, 2014 Acquisitions Foreign Exchange December 26, 2015 (in thousands) RMS $ 83,551 $ — $ (23,172 ) $ (1,183 ) $ 59,196 $ — $ (1,029 ) $ 58,167 DSA 1,152,150 102,171 (9,196 ) (10,823 ) 1,234,302 22,146 (4,398 ) 1,252,050 Manufacturing — — 32,368 211 32,579 105,567 (4,534 ) 133,612 Gross carrying amount 1,235,701 1,326,077 1,443,829 DSA - Accumulated impairment loss (1,005,000 ) — — — (1,005,000 ) — — (1,005,000 ) Goodwill $ 230,701 $ 321,077 $ 438,829
Schedule of Finite-Lived Intangible Assets by major class	The following table displays the gross carrying amount and accumulated amortization of intangible assets, net by major class: December 26, 2015 December 27, 2014 Gross Accumulated Net Gross Accumulated Net (in thousands) Backlog $ 50,568 $ (50,554 ) $ 14 $ 8,728 $ (6,636 ) $ 2,092 Technology (1) 60,350 (5,911 ) 54,439 13,474 (4,166 ) 9,308 Trademarks and trade names 11,495 (5,944 ) 5,551 6,603 (5,314 ) 1,289 Other identifiable intangible assets 14,711 (7,285 ) 7,426 5,169 (3,822 ) 1,347 Definite-lived other intangible assets, net 137,124 (69,694 ) 67,430 33,974 (19,938 ) 14,036 Indefinite-lived intangibles (1) — 3,438 Total other intangible assets, net 67,430 17,474 Client relationships 396,537 (183,163 ) 213,374 379,339 (217,938 ) 161,401 Total intangible assets, net $ 280,804 $ 178,875 (1) During the fourth quarter of 2015, certain intangible assets with a carrying value of $3.4 million that were previously assigned indefinite lives have been assigned definite lives of 20 years. The Company recorded an immaterial amount of amortization expense on these intangible assets during the fiscal year 2015.
Schedule of Estimated Amortization Expense	Estimated amortization expense for intangible assets for each of the next five fiscal years is expected to be as follows: Fiscal Year Amortization Expense (in thousands) 2016 $ 26,835 2017 26,678 2018 24,434 2019 21,617 2020 21,293

Long-Term Debt and Capital Le31

Long-Term Debt and Capital Lease Obligations (Tables)	12 Months Ended
	Dec. 26, 2015
Debt Disclosure [Abstract]
Schedule of Debt	Long-term debt, net consists of the following: December 26, 2015 December 27, 2014 (in thousands) Term loans $ 390,000 $ 378,000 Revolving credit facility 446,041 375,536 Other long-term debt 193 214 Total debt 836,234 753,750 Less: current portion of long-term debt (15,193 ) (31,714 ) Long-term debt 821,041 722,036 Debt discount and debt issuance costs (1) (6,805 ) (5,401 ) Long-term debt, net $ 814,236 $ 716,635 (1) During the second quarter of 2015, the Company adopted ASU 2015-03 and reclassified unamortized debt issuance costs from other assets to long-term debt, net and capital leases. See Note 1, “Basis of Presentation” for further discussion.
Schedule of Maturities of Long Term Debt	Principal maturities of existing debt for the periods set forth in the table below, are as follows: Fiscal Year Principal (in thousands) 2016 $ 15,193 2017 22,500 2018 32,500 2019 50,000 2020 716,041 Total $ 836,234

Equity and Redeemable Noncont32

Equity and Redeemable Noncontrolling Interest (Tables)	12 Months Ended
	Dec. 26, 2015
Stockholders' Equity Note [Abstract]
Reconciliation of the Numerator and Denominator in the Computations of the Basic and Diluted Earnings per Share	The following table reconciles the numerator and denominator in the computations of basic and diluted earnings per share: Fiscal Year 2015 2014 2013 (in thousands) Numerator: Net income from continuing operations attributable to common shareholders $ 150,263 $ 128,424 $ 104,093 Loss from discontinued operations, net of income taxes (950 ) (1,726 ) (1,265 ) Net income attributable to common shareholders $ 149,313 $ 126,698 $ 102,828 Denominator: Weighted-average shares outstanding—Basic 46,496 46,627 47,740 Effect of dilutive securities: Stock options, restricted stock units, performance share units and restricted stock 1,138 931 749 Weighted-average shares outstanding—Diluted 47,634 47,558 48,489
Schedule of composition of accumulated other comprehensive income	Changes to each component of accumulated other comprehensive income (loss), net of income taxes, are as follows: Foreign Currency Translation and Other (3) Pension and Other Post-Retirement Benefit Plans Total (in thousands) December 28, 2013 $ 28,503 $ (23,146 ) $ 5,357 Other comprehensive loss before reclassifications (1) (48,499 ) (42,236 ) (90,735 ) Amounts reclassified from accumulated other comprehensive income (loss) — 1,234 1,234 Net current period other comprehensive loss (48,499 ) (41,002 ) (89,501 ) Income tax benefit 105 9,792 9,897 December 27, 2014 (19,891 ) (54,356 ) (74,247 ) Other comprehensive loss before reclassifications (2) (60,745 ) (302 ) (61,047 ) Amounts reclassified from accumulated other comprehensive income (loss) (2,341 ) 2,617 276 Net current period other comprehensive (loss) (63,086 ) 2,315 (60,771 ) Income tax expense — (530 ) (530 ) December 26, 2015 $ (82,977 ) $ (52,571 ) $ (135,548 ) (1) The impact of the foreign currency translation adjustment to other comprehensive income (loss) before reclassifications for the fiscal year 2014 was primarily due to the effect of changes in foreign currency exchange rates of the Euro and Canadian Dollar and to a lesser extent due to the impact of changes in the Japanese Yen and British Pound. (2) The impact of the foreign currency translation adjustment to other comprehensive income (loss) before reclassifications for the fiscal year 2015 was primarily due to the effect of changes in foreign currency exchange rates of the Euro and Canadian Dollar and to a lesser extent due to the impact of changes in the British Pound. (3) Foreign currency translation and other includes an insignificant amount of unrealized gains (losses) on available-for-sale marketable securities.

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 26, 2015
Income Tax Disclosure [Abstract]
Analysis of the components of income (loss) from continuing operations before income taxes and the related provision for income taxes	The components of income from continuing operations before income taxes and the related provision for income taxes are presented below: Fiscal Year 2015 2014 2013 (in thousands) Income from continuing operations before income taxes: U.S. $ 76,157 $ 71,002 $ 39,900 Non-U.S. 119,271 106,593 98,427 $ 195,428 $ 177,595 $ 138,327 Income tax provision: Current: Federal 23,687 13,733 10,832 Foreign 8,572 20,364 18,370 State 6,819 4,746 4,240 Total current 39,078 38,843 33,442 Deferred: Federal 1,790 12,982 5,468 Foreign 3,064 (4,672 ) (6,431 ) State (541 ) 518 432 Total deferred 4,313 8,828 (531 ) $ 43,391 $ 47,671 $ 32,911
Schedule of net deferred taxes	The components of deferred tax assets and liabilities are as follows: December 26, 2015 December 27, 2014 (in thousands) Deferred tax assets: Compensation $ 55,259 $ 49,702 Accruals and reserves 8,941 7,061 Inventory reserves and valuations 2,022 1,940 Financing related 902 993 Net operating loss and credit carryforwards 35,233 39,927 Other 2,593 4,426 Valuation allowance (6,112 ) (5,866 ) Total deferred tax assets: 98,838 98,183 Deferred tax liabilities: Goodwill and other intangibles (73,208 ) (52,029 ) Depreciation related (23,664 ) (23,549 ) Investments in limited partnerships (3,570 ) (4,067 ) Foreign withholding taxes (6,590 ) — Total deferred tax liabilities: (107,032 ) (79,645 ) Net deferred taxes $ (8,194 ) $ 18,538
Reconciliation of statutory U.S. federal income tax rate to effective tax rates	Reconciliations of the statutory U.S. Federal income tax rate to effective tax rates are as follows: Fiscal Year 2015 2014 2013 U.S. statutory income tax rate 35.0 % 35.0 % 35.0 % Foreign tax rate differences (8.6 )% (9.4 )% (8.0 )% State income taxes, net of Federal tax benefit 1.9 % 1.9 % 1.6 % Research tax credits and enhanced deductions (2.6 )% (4.1 )% (6.6 )% Enacted tax rate changes (1.5 )% — % (0.4 )% Impact of tax uncertainties (5.2 )% (0.7 )% 1.0 % Foreign withholding taxes 3.4 % — % — % Impact of acquisitions and restructuring (2.0 )% 1.6 % 0.2 % Other 1.8 % 2.5 % 1.0 % 22.2 % 26.8 % 23.8 %
Reconciliation of unrecognized income tax benefits	A reconciliation of the Company’s beginning and ending unrecognized income tax benefits is as follows: Fiscal Year 2015 2014 2013 (in thousands) Beginning balance $ 34,627 $ 18,475 $ 30,996 Additions to tax positions for current year 2,362 1,700 2,009 Additions to tax positions for prior years 3,028 18,502 1,709 Reductions to tax positions for current year — — — Reductions to tax positions for prior years (3,991 ) (3,722 ) (732 ) Settlements (1,946 ) (308 ) (15,246 ) Expiration of statute of limitations (10,742 ) (20 ) (261 ) Ending balance $ 23,338 $ 34,627 $ 18,475

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 26, 2015
Compensation and Retirement Disclosure [Abstract]
Schedule of obligations and funded status	The following tables provide a reconciliation of benefit obligations and plan assets of the Company’s pension plans and other post-retirement benefit plans: Pension Plans Other Post-Retirement Benefit Plans December 26, 2015 December 27, 2014 December 26, 2015 December 27, 2014 (in thousands) Change in projected benefit obligations: Benefit obligation at beginning of year $ 326,884 $ 286,212 $ 32,246 $ 29,498 Service cost 3,437 3,397 856 758 Interest cost 11,912 12,822 1,062 1,009 Benefit payments (7,517 ) (9,002 ) (674 ) (722 ) Actuarial loss (gain) (11,783 ) 50,550 1,421 1,703 Administrative expenses paid (411 ) (459 ) — — Effect of foreign exchange (12,213 ) (16,636 ) — — Benefit obligation at end of year $ 310,309 $ 326,884 $ 34,911 $ 32,246 Change in fair value of plan assets: Fair value of plan assets at beginning of year 281,290 272,659 — — Actual return on plan assets 6,263 25,630 — — Employer contributions 6,088 6,874 674 722 Benefit payments (7,517 ) (9,002 ) (674 ) (722 ) Premiums paid (411 ) (459 ) — — Effect of foreign exchange (10,233 ) (14,412 ) — — Fair value of plan assets at end of year $ 275,480 $ 281,290 $ — $ — Net balance sheet liability $ 34,829 $ 45,594 $ 34,911 $ 32,246 Amounts recognized in balance sheet: Noncurrent assets $ 261 $ 61 $ — $ — Current liabilities 149 169 5,984 744 Noncurrent liabilities 34,941 45,486 28,927 31,502
Schedule of amounts recognized as part of accumulated other comprehensive income (loss)	Amounts recognized in accumulated other comprehensive loss: Pension Plans Other Post-Retirement Benefit Plans Fiscal Year Fiscal Year 2015 2014 2015 2014 (in thousands) Net actuarial loss $ 66,499 $ 73,433 $ 6,913 $ 5,761 Net prior service cost (credit) (4,584 ) (5,388 ) — — Net amount recognized $ 61,915 $ 68,045 $ 6,913 $ 5,761
Schedule of defined benefit plans with accumulated benefit obligation and fair value of plan assets in excess of plan assets	The accumulated benefit obligation and fair value of plan assets for the Company plans with accumulated benefit obligations in excess of plan assets are as follows: Pension Plans Other Post-Retirement Benefit Plans December 26, 2015 December 27, 2014 December 26, 2015 December 27, 2014 (in thousands) Accumulated benefit obligation $ 275,849 $ 299,127 $ 30,584 $ 29,994 Fair value of plan assets 253,225 267,026 — —
Schedule of defined benefit plans with projected benefit obligation and fair value of plan assets in excess of plan assets	The projected benefit obligation and fair value of plan assets for the Company plans with projected benefit obligations in excess of plan assets are as follows: Pension Plans Other Post-Retirement Benefit Plans December 26, 2015 December 27, 2014 December 26, 2015 December 27, 2014 (in thousands) Projected benefit obligation $ 301,244 $ 326,731 $ 34,911 $ 32,246 Fair value of plan assets 266,154 281,075 — —
Schedule of amounts in AOCI expected to be recognized as components of net periodic benefit cost over the next fiscal year	The amounts in accumulated other comprehensive income expected to be recognized as components of net periodic benefit cost over the next fiscal year are as follows: Pension Plans Other Post-Retirement Benefit Plans (in thousands) Amortization of net actuarial loss $ 1,931 $ 251 Amortization of net prior service credit (576 ) —
Components of net periodic benefit cost for defined benefit plans	Components of net periodic benefit cost: Pension Plans Other Post-Retirement Benefit Plans Fiscal Year Fiscal Year 2015 2014 2013 2015 2014 2013 (in thousands) Service cost $ 3,437 $ 3,397 $ 3,368 $ 856 $ 758 $ 643 Interest cost 11,912 12,822 11,273 1,062 1,009 708 Expected return on plan assets (16,987 ) (17,444 ) (14,672 ) — — — Amortization of prior service cost (credit) (581 ) 961 2,711 — 250 249 Amortization of net loss (gain) 2,929 (637 ) (603 ) 269 660 660 Net periodic cost (benefit) $ 710 $ (901 ) $ 2,077 $ 2,187 $ 2,677 $ 2,260
Schedule of weighted-average assumptions	Weighted-average assumptions used to determine projected benefit obligations: Pension Plans Other Post-Retirement Benefit Plans December 26, 2015 December 27, 2014 December 26, 2015 December 27, 2014 Discount rate 3.93 % 3.79 % 3.56 % 3.34 % Rate of compensation increase 3.19 % 3.19 % 3.00 % 3.00 % Weighted-average assumptions used to determine net periodic benefit cost: Pension Plans Other Post-Retirement Benefit Plans December 26, 2015 December 27, 2014 December 28, 2013 December 26, 2015 December 27, 2014 December 28, 2013 Discount rate 3.79 % 4.54 % 4.13 % 3.34 % 3.47 % 2.63 % Expected long-term return on plan assets 6.24 % 6.41 % 6.27 % — — — Rate of compensation increase 3.19 % 3.39 % 3.04 % 3.00 % 3.00 % 2.50 %
Defined benefit plan, additional disclosures about plan assets	The fair value of the Company’s pension plan assets by asset category are as follows: December 26, 2015 December 27, 2014 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total (in thousands) Cash $ 92 $ — $ — $ 92 $ 1 $ — $ — $ 1 Equity securities (a) 65,890 5,941 — 71,831 80,692 5,126 — 85,818 Debt securities (b) 68,489 2,822 — 71,311 69,716 3,232 — 72,948 Mutual funds (c) 63,689 65,725 — 129,414 67,079 53,330 — 120,409 Other 1,021 49 1,762 2,832 297 46 1,771 2,114 Total $ 199,181 $ 74,537 $ 1,762 $ 275,480 $ 217,785 $ 61,734 $ 1,771 $ 281,290 (a) This category comprises equity securities held by non-U.S. pension plans valued at the quoted closing price, and translated into U.S. dollars using a foreign currency exchange rate at year end. (b) This category comprises debt securities held by non-U.S. pension plans valued at the quoted closing price, and translated into U.S. dollars using a foreign currency exchange rate at year end. (c) This category comprises mutual funds valued at the net asset value of shares held at year end.
Schedule of estimated future benefit payments	Estimated future benefit payments during the next five years and in the aggregate for the fiscal years thereafter, are as follows: Pension Plans Other Post-Retirement Benefit Plans (in thousands) 2016 $ 7,561 $ 6,087 2017 7,914 747 2018 8,361 734 2019 8,926 722 2020 9,379 709 Thereafter 52,917 24,480

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 26, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of stock-based compensation expense	The following table provides the financial statement line items in which stock-based compensation is reflected: Fiscal Year 2015 2014 2013 (in thousands) Cost of revenue (excluding amortization of intangible assets) $ 6,511 $ 5,382 $ 5,381 Selling, general and administrative 33,611 25,653 19,161 Stock-based compensation expense, before income taxes 40,122 31,035 24,542 Provision for income taxes (14,225 ) (11,006 ) (8,658 ) Stock-based compensation, net of income taxes $ 25,897 $ 20,029 $ 15,884
Summary of stock option activity in equity incentive plans	The following table summarizes stock option activities under the Company’s stock-based compensation plans: Number of shares Weighted Average Weighted Average Aggregate (in thousands, except per share amounts) Options outstanding as of December 27, 2014 2,553 $ 43.39 Options granted 474 $ 76.33 Options exercised (909 ) $ 43.34 Options canceled (52 ) $ 55.78 Options outstanding as of December 26, 2015 2,066 $ 50.62 3.7 $ 60,846 Options exercisable as of December 26, 2015 834 $ 37.88 2.6 $ 35,200 Options expected to vest at December 26, 2015 1,219 $ 59.21 4.4 $ 25,448
Schedule of stock option weighted-average assumptions	The fair value of stock options granted was estimated using the Black-Scholes option-pricing model with the following weighted-average assumptions: Fiscal Year 2015 2014 2013 Expected life (in years) 3.6 4.2 4.2 Expected volatility 28 % 30 % 33 % Risk-free interest rate 1.1 % 1.5 % 0.8 % Expected dividend yield 0 % 0 % 0 %
Summary of restricted stock activity	The following table summarizes the restricted stock and restricted stock units activity for the fiscal year 2015 : Restricted Stock and Restricted Stock Units Weighted (in thousands) December 27, 2014 803 $ 44.67 Granted 198 76.16 Vested (365 ) 42.95 Canceled (29 ) 54.08 December 26, 2015 607 $ 55.52
PSU activity and weighted average assumptions	The Company utilizes a Monte Carlo simulation valuation model to value these awards. Information pertaining to the Company’s PSUs and the related estimated weighted-average assumptions used to calculate their fair value were as follows: Fiscal Year 2015 2014 2013 PSUs granted 148,900 214,823 163,847 Weighted average per share fair value $88.62 $67.82 $44.47 Key Assumptions: Expected volatility 23 % 29 % 32 % Risk-free interest rate 0.96 % 0.63 % 0.38 % Expected dividend yield — % — % — % 20 trading day average stock price on grant date 20.6 % 13.1 % 6.9 %

Foreign Currency Contracts (Tab

Foreign Currency Contracts (Tables)	12 Months Ended
	Dec. 26, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair Value and Notational Value of Foreign Currency Contracts	The notional amount and fair value of the Company’s foreign currency forward contracts is summarized as follows: December 26, 2015 Notional Amount Fair Value Balance Sheet Location (in thousands) $ 88,483 $ 15 Other current assets
Derivative Instruments, Gain (Loss)	The following table summarizes the effect of foreign exchange forward contracts on the Company’s consolidated statement of income: Fiscal Year 2015 Location of Gain (Loss) Gain (Loss) Recognized (in thousands) Other income (expense), net $ (4,917 )

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 26, 2015
Commitments and Contingencies Disclosure [Abstract]
Schedule of future minimum payments under noncancellable operating leases	As of December 26, 2015 , minimum rental commitments under non-cancelable leases, net of income from subleases, for each of the next five years and total thereafter were as follows: Minimum Lease Payments (in thousands) 2016 $ 19,702 2017 17,841 2018 12,009 2019 9,783 2020 7,969 Thereafter 18,086 Total $ 85,390

Business Segment and Geographic

Business Segment and Geographic Information (Tables)	12 Months Ended
	Dec. 26, 2015
Segment Reporting [Abstract]
Schedule of sales and other financial information by business segment	The following table presents revenue and other financial information by reportable segment: Fiscal Year 2015 2014 2013 (in thousands) RMS Revenue $ 473,230 $ 507,327 $ 511,350 Operating income 121,447 121,376 116,737 Depreciation and amortization 22,688 27,512 41,837 Capital expenditures 17,398 18,749 16,717 DSA Revenue $ 612,173 $ 538,218 $ 432,378 Operating income 121,981 69,749 47,413 Depreciation and amortization 46,812 47,138 37,720 Capital expenditures 30,333 19,759 12,561 Manufacturing Revenue $ 277,899 $ 252,117 $ 221,800 Operating income 74,201 78,620 61,227 Depreciation and amortization 17,967 14,092 17,079 Capital expenditures 9,814 15,541 9,876
Reconciliation of segment operating income to consolidated operating income	For the fiscal years ended 2015 , 2014 and 2013 , reconciliations of segment operating income and capital expenditures to the respective consolidated amounts are as follows: Operating Income Capital Expenditures Fiscal Year Fiscal Year 2015 2014 2013 2015 2014 2013 (in thousands) Total reportable segments $ 317,629 $ 269,745 $ 225,377 $ 57,545 $ 54,049 $ 39,154 Unallocated corporate (111,180 ) (92,075 ) (73,976 ) 5,707 2,876 — Total consolidated $ 206,449 $ 177,670 $ 151,401 $ 63,252 $ 56,925 $ 39,154
Schedule of net sales for each significant service area	Revenue for each significant product or service offering is as follows : Fiscal Year 2015 2014 2013 (in thousands) RMS $ 473,230 $ 507,327 $ 511,350 DSA 612,173 538,218 432,378 Manufacturing 277,899 252,117 221,800 Total revenue $ 1,363,302 $ 1,297,662 $ 1,165,528
Summary of unallocated corporate overhead	A summary of unallocated corporate overhead consists of the following : Fiscal Year 2015 2014 2013 (in thousands) Stock-based compensation expense $ 25,751 $ 18,474 $ 13,411 Salary, bonus and fringe 33,026 30,838 23,446 Consulting, audit and professional services 15,418 13,431 8,666 IT related expenses 8,400 6,528 11,646 Depreciation expense 7,414 7,703 6,334 Acquisition related adjustments 11,644 6,285 1,752 Other general unallocated corporate expenses 9,527 8,816 8,721 Total unallocated corporate overhead costs $ 111,180 $ 92,075 $ 73,976
Schedule of sales and other financial information by geographic regions	Revenue and long-lived assets by geographic area are as follows: U.S. Europe Canada Japan Other Non-U.S. Consolidated (in thousands) 2015 Revenue $ 659,466 $ 435,491 $ 172,349 $ 40,520 $ 55,476 $ 1,363,302 Long-lived assets 402,238 159,445 77,535 22,348 16,393 677,959 2014 Revenue $ 588,531 $ 446,263 $ 163,490 $ 49,921 $ 49,457 $ 1,297,662 Long-lived assets 386,624 153,203 95,272 23,896 17,802 676,797 2013 Revenue $ 551,340 $ 353,688 $ 162,404 $ 59,370 $ 38,726 $ 1,165,528 Long-lived assets 447,829 130,855 109,811 30,589 19,062 738,146

Selected Quarterly Financial 39

Selected Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 26, 2015
Selected Quarterly Financial Data [Abstract]
Selected Quarterly Financial Data	The following table contains quarterly financial information for fiscal years 2015 and 2014 . The operating results for any quarter are not necessarily indicative of future period results: First Quarter Second Quarter Third Quarter Fourth Quarter Fiscal Year 2015 (in thousands, except per share amounts) Total revenue $ 320,414 $ 339,573 $ 349,465 $ 353,850 Gross profit (1) 119,660 132,783 138,075 140,574 Operating income 43,005 55,735 55,440 52,269 Net income attributable to common shareholders 31,541 48,509 37,379 31,884 Earnings (loss) per common share: Basic: Continuing operations attributable to common shareholders $ 0.67 $ 1.04 $ 0.81 $ 0.71 Discontinued operations — — — (0.02 ) Net income attributable to common shareholders $ 0.67 $ 1.04 $ 0.81 $ 0.69 Diluted: Continuing operations attributable to common shareholders $ 0.66 $ 1.02 $ 0.79 $ 0.69 Discontinued operations — — — (0.02 ) Net income attributable to common shareholders $ 0.66 $ 1.02 $ 0.79 $ 0.67 Fiscal Year 2014 Total revenue $ 299,368 $ 341,179 $ 327,567 $ 329,548 Gross profit (1) 108,813 125,634 118,268 119,945 Operating income 39,706 51,025 46,172 40,767 Net income attributable to common shareholders 32,232 35,264 32,036 27,166 Earnings (loss) per common share: Basic: Continuing operations attributable to common shareholders $ 0.69 $ 0.76 $ 0.70 $ 0.60 Discontinued operations (0.01 ) (0.01 ) — (0.02 ) Net income attributable to common shareholders $ 0.68 $ 0.75 $ 0.70 $ 0.58 Diluted: Continuing operations attributable to common shareholders $ 0.67 $ 0.75 $ 0.68 $ 0.59 Discontinued operations (0.01 ) (0.01 ) — (0.02 ) Net income attributable to common shareholders $ 0.67 $ 0.74 $ 0.68 $ 0.57 (1) Gross profit is calculated as total revenues minus cost of revenue, excluding amortization of intangible assets.

Description of Business and S40

Description of Business and Summary of Significant Accounting Policies Reportable segments (Details)	Jun. 27, 2014	Dec. 26, 2015
Segment Reporting [Abstract]
Number of reportable segments	2	3

Description of Business and S41

Description of Business and Summary of Significant Accounting Policies Cash and Cash Equivalents, Trade Receivables and Concentrations of Credit Risk (Details) - Client Concentration Risk	12 Months Ended
	Dec. 26, 2015customers
Composition of trade receivables
Number of clients representing large percentage of sales or trade receivables	0
Max percentage, clients representing large percentage of sales or trade receivables	5.00%

Description of Business and S42

Description of Business and Summary of Significant Accounting Policies Property, Plant and Equipment (Details)	12 Months Ended
	Dec. 26, 2015
Minimum | Buildings
Property, Plant and Equipment [Line Items]
Useful life	20 years
Minimum | Machinery and equipment
Property, Plant and Equipment [Line Items]
Useful life	3 years
Minimum | Furniture and fixtures
Property, Plant and Equipment [Line Items]
Useful life	5 years
Minimum | Computer hardware and software
Property, Plant and Equipment [Line Items]
Useful life	3 years
Minimum | Vehicles
Property, Plant and Equipment [Line Items]
Useful life	3 years
Maximum | Buildings
Property, Plant and Equipment [Line Items]
Useful life	40 years
Maximum | Machinery and equipment
Property, Plant and Equipment [Line Items]
Useful life	20 years
Maximum | Furniture and fixtures
Property, Plant and Equipment [Line Items]
Useful life	10 years
Maximum | Computer hardware and software
Property, Plant and Equipment [Line Items]
Useful life	8 years
Maximum | Vehicles
Property, Plant and Equipment [Line Items]
Useful life	5 years

Description of Business and S43

Description of Business and Summary of Significant Accounting Policies Limited Partnership (Details)	Dec. 26, 2015
Minimum
Schedule of Equity Method Investments [Line Items]
Limited partnerships, ownership percentage	3.60%
Maximum
Schedule of Equity Method Investments [Line Items]
Limited partnerships, ownership percentage	12.00%

Description of Business and S44

Description of Business and Summary of Significant Accounting Policies Life Insurance Contracts (Details) $ in Millions	Dec. 26, 2015USD ($)contract	Dec. 27, 2014USD ($)contract
Description of Business and Summary of Significant Accounting Policies [Abstract]
Life insurance contracts, number of contracts | contract	42	40
Life insurance contracts, face value | $	$ 60.5	$ 68.2

Description of Business and S45

Description of Business and Summary of Significant Accounting Policies Revenue Recognition (Details)	Dec. 26, 2015milestone
Description of Business and Summary of Significant Accounting Policies [Abstract]
Revenue recognition, number of milestones achieved	0

Description of Business and S46

Description of Business and Summary of Significant Accounting Policies Advertising Costs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Description of Business and Summary of Significant Accounting Policies [Abstract]
Advertising Expense	$ 1.2	$ 1.3	$ 1.1

Description of Business and S47

Description of Business and Summary of Significant Accounting Policies Pension and Other Post-Retirement Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014
Change in Discount Rate Methodology
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Increase (decrease) in pension and postretirement obligations		$ 5.5
US Pension Plan | Change in Mortality Tables
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Increase (decrease) in pension and postretirement obligations	$ 3.3	$ 7.9

Description of Business and S48

Description of Business and Summary of Significant Accounting Policies Newly Adopted Accounting Pronouncements (Details) $ in Millions	12 Months Ended
	Dec. 27, 2014USD ($)
Other Current Assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change resulting from newly adopted accounting pronouncements	$ 27.6
Other Current Liabilities
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change resulting from newly adopted accounting pronouncements	1.5
Noncurrent Deferred Tax Liabilities
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change resulting from newly adopted accounting pronouncements	7.7
Noncurrent Deferred Tax Assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change resulting from newly adopted accounting pronouncements	18.4
Deferred Debt Issuance Costs
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Change resulting from newly adopted accounting pronouncements	$ 5.4

Business Acquisitions Oncotest

Business Acquisitions Oncotest Additional Information (Details) - Oncotest $ in Thousands, € in Millions	Nov. 18, 2015USD ($)	Dec. 26, 2015USD ($)	Dec. 26, 2015EUR (€)	Dec. 26, 2015USD ($)
Business Acquisition [Line Items]
Purchase price	$ 36,000
Maximum contingent consideration			€ 2	$ 2,200
Contingent consideration, liability	300
Total purchase price allocation	35,431
Cash acquired in excess of payments to acquire business	$ 600
Transaction and integration costs		$ 2,100

Business Acquisitions Oncotes50

Business Acquisitions Oncotest Purchase Price Allocation (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Nov. 18, 2015	Dec. 27, 2014	Dec. 28, 2013
Business Acquisition [Line Items]
Goodwill	$ 438,829		$ 321,077	$ 230,701
Oncotest
Business Acquisition [Line Items]
Trade receivables		$ 3,520
Inventories		129
Other current assets (excluding cash)		706
Property, plant and equipment		2,528
Definite-lived intangible assets		13,330
Goodwill		22,894
Other long-term assets		250
Current liabilities		(3,456)
Long-term liabilities		(4,470)
Total purchase price allocation		35,431
Acquired receivables, contractual amount		$ 3,546

Business Acquisitions Oncotes51

Business Acquisitions Oncotest Definite-Lived Intangible Assets (Details) - Oncotest $ in Thousands	Nov. 18, 2015USD ($)
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 13,330
Client relationships, net
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 7,146
Weighted average amortization life	19 years
Developed technology
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 5,960
Weighted average amortization life	19 years
Other intangible assets
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 224
Weighted average amortization life	3 years

Business Acquisitions Celsis, A

Business Acquisitions Celsis, Additional Information (Details) - Celsis Group Limited - USD ($) $ in Thousands	Jul. 24, 2015	Dec. 26, 2015	Dec. 27, 2014
Business Acquisition [Line Items]
Purchase price	$ 214,500
Total purchase price allocation	10,300
Total purchase price allocation	212,236
Cash acquired in excess of payments to acquire business	$ 2,300
Transaction and integration costs		$ 8,800
Pro forma information, revenue of acquiree since acquisition date		11,100
Pro forma information, earnings or loss of acquiree since acquisition date		6,100
Pro forma adjustments, acquisitions		$ 600	$ 13,100

Business Acquisitions Celsis Pu

Business Acquisitions Celsis Purchase Price Acquisitions (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Nov. 18, 2015	Jul. 24, 2015	May. 05, 2015	Dec. 27, 2014	Dec. 28, 2013
Business Acquisition [Line Items]
Goodwill	$ 438,829				$ 321,077	$ 230,701
Celsis Group Limited
Business Acquisition [Line Items]
Trade receivables			$ 5,288
Inventories			10,103
Other current assets (excluding cash)			13,432
Property, plant and equipment			4,639
Definite-lived intangible assets			118,140
Goodwill			105,380
Other long-term assets			614
Short-term debt			(9,766)
Current liabilities			(7,448)
Long-term liabilities			(28,146)
Total purchase price allocation			212,236
Acquired receivables, contractual amount			$ 5,410
Sunrise
Business Acquisition [Line Items]
Trade receivables				$ 981
Inventories				1,518
Other current assets (excluding cash)				973
Property, plant and equipment				13,698
Definite-lived intangible assets				3,400
Acquired receivables, contractual amount				$ 995
Oncotest
Business Acquisition [Line Items]
Trade receivables		$ 3,520
Inventories		129
Other current assets (excluding cash)		706
Property, plant and equipment		2,528
Definite-lived intangible assets		13,330
Goodwill		22,894
Other long-term assets		250
Current liabilities		(3,456)
Long-term liabilities		(4,470)
Total purchase price allocation		35,431
Acquired receivables, contractual amount		$ 3,546

Business Acquisitions Celsis De

Business Acquisitions Celsis Definite-Lived Intangible Assets (Details) - Celsis Group Limited $ in Thousands	Jul. 24, 2015USD ($)
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 118,140
Client relationships
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 71,000
Weighted average amortization life	16 years
Developed technology
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 39,140
Weighted average amortization life	14 years
Trademark and trade names
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 5,200
Weighted average amortization life	14 years
Non-compete
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 2,800
Weighted average amortization life	5 years

Business Acquisitions Celsis Pr

Business Acquisitions Celsis Pro Forma Results (Details) - Celsis Group Limited - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014
Business Acquisition [Line Items]
Revenue	$ 1,380,493	$ 1,329,025
Net income attributable to common shareholders	$ 162,672	$ 110,387
Earnings per share, basic (in usd per share)	$ 3.50	$ 2.37
Earnings per share, diluted (in usd per share)	$ 3.42	$ 2.32

Business Acquisitions Sunrise,

Business Acquisitions Sunrise, Additional Information (Details) - USD ($) $ in Thousands	May. 05, 2015	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Business Acquisition [Line Items]
Gain on bargain purchase		$ 9,837	$ 0	$ 0
Sunrise
Business Acquisition [Line Items]
Total purchase price allocation	$ 9,558
Gain on bargain purchase	9,837
Cash acquired in excess of payments to acquire business	$ 100
Purchase price allocation, period of adjustment, maximum		1 year
Transaction and integration costs		$ 1,500
Client relationships | Sunrise
Business Acquisition [Line Items]
Finite-lived intangible asset, useful life		15 years

Business Acquisitions Sunrise P

Business Acquisitions Sunrise Purchase Price Allocation (Details) - USD ($) $ in Thousands	May. 05, 2015	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Business Acquisition [Line Items]
Bargain purchase gain		$ 9,837	$ 0	$ 0
Sunrise
Business Acquisition [Line Items]
Trade receivables	$ 981
Inventories	1,518
Other current assets (excluding cash)	973
Property, plant and equipment	13,698
Definite-lived intangible assets	3,400
Current liabilities	(925)
Long-term liabilities	(250)
Total purchase price allocation	19,395
Bargain purchase gain	9,837
Total purchase price allocation	9,558
Acquired receivables, contractual amount	$ 995

Business Acquisitions ChanTest,

Business Acquisitions ChanTest, Additional Information (Details) - USD ($)	Oct. 29, 2014	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Business Acquisition [Line Items]
Consideration, net of cash acquired		$ 247,651,000	$ 234,267,000	$ 29,218,000
ChanTest
Business Acquisition [Line Items]
Consideration, gross	$ 59,200,000
Contingent consideration, liability	300,000
Contingent consideration	2,000,000
Consideration, net of cash acquired	52,000,000
Cash acquired from acquisition	$ 7,200,000
ChanTest
Business Acquisition [Line Items]
Contingent consideration, gain		$ 300,000
Transaction and integration costs			$ 1,100,000

Business Acquisitions ChanTest

Business Acquisitions ChanTest Preliminary Purchase Price (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014	Oct. 29, 2014	Dec. 28, 2013
Business Acquisition [Line Items]
Goodwill	$ 438,829	$ 321,077		$ 230,701
ChanTest
Business Acquisition [Line Items]
Current assets (excluding cash)			$ 4,669
Property, plant and equipment			1,637
Definite-lived intangible assets			23,920
Goodwill			34,775
Current liabilities			(3,486)
Long-term liabilities			(9,486)
Total purchase price allocation			$ 52,029

Business Acquisitions ChanTes60

Business Acquisitions ChanTest Breakout of Definite-Lived Intangible Assets Acquired (Details) - ChanTest $ in Thousands	Oct. 29, 2014USD ($)
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 23,920
Client relationships
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 19,000
Weighted average amortization life	13 years
Other intangible assets
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 4,920
Weighted average amortization life	9 years

Business Acquisitions VivoPath

Business Acquisitions VivoPath (Details) - VivoPath - USD ($)	Jun. 16, 2014	Dec. 26, 2015
Business Acquisition [Line Items]
Consideration, gross	$ 2,300,000
Contingent consideration, liability	1,600,000
Maximum contingent consideration	$ 2,400,000	$ 400,000
Business Combination, Contingent Consideration Arrangements, Earn Out Period		3 years
Contingent consideration, settlement		$ 600,000
Contingent consideration, change in amount		$ 800,000

Business Acquisitions Early Dis

Business Acquisitions Early Discovery, Additional Information (Details) - Early Discovery UK € in Millions, $ in Millions	Apr. 01, 2015USD ($)	Apr. 01, 2014USD ($)	Dec. 27, 2014USD ($)	Dec. 26, 2015EUR (€)	Dec. 26, 2015USD ($)
Business Acquisition [Line Items]
Percentage of voting interests acquired		100.00%
Purchase price		$ 191.8
Contingent consideration, liability		0.9
Contingent consideration, change in amount	$ (0.8)
Maximum contingent consideration				€ 5	$ 5.5
Total purchase price allocation		183.6
Cash acquired from business acquisition		8.2
Acquisition related adjustments			$ 5.3
Pro forma information, revenue of acquiree since acquisition date			71.4
Pro forma information, earnings or loss of acquiree since acquisition date			$ 1.8
Pro forma adjustments, acquisitions		$ 3.7

Business Acquisitions Early D63

Business Acquisitions Early Discovery Purchase Price Allocation (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014	Apr. 01, 2014	Dec. 28, 2013
Business Acquisition [Line Items]
Goodwill	$ 438,829	$ 321,077		$ 230,701
Early Discovery UK
Business Acquisition [Line Items]
Current assets (excluding cash)			$ 31,682
Property, plant and equipment			21,008
Other long-term assets			11,140
Definite-lived intangible assets			104,470
Goodwill			65,235
Current liabilities			(13,139)
Long-term liabilities			(36,802)
Total purchase price allocation			$ 183,594

Business Acquisitions Early D64

Business Acquisitions Early Discovery Breakout of Definite-Lived Intangible Assets Acquired (Details) - Early Discovery UK $ in Thousands	Apr. 01, 2014USD ($)
Business Acquisition [Line Items]
Total purchase price allocation	$ 104,470
Client relationships
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 94,000
Weighted average amortization life	18 years
Backlog
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 5,900
Weighted average amortization life	1 year
Trademark and trade names
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 1,170
Weighted average amortization life	3 years
Leasehold interests
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 1,000
Weighted average amortization life	13 years
Other intangible assets
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 2,400
Weighted average amortization life	19 years

Business Acquisitions Early D65

Business Acquisitions Early Discovery Pro Forma Information (Details) - Early Discovery UK - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 27, 2014	Dec. 28, 2013
Business Acquisition [Line Items]
Revenue	$ 1,322,771	$ 1,249,649
Net income attributable to common shareholders	$ 128,195	$ 98,508
Earnings per share, basic (in usd per share)	$ 2.75	$ 2.06
Earnings per share, diluted (in usd per share)	$ 2.70	$ 2.03

Business Acquisitions EMD Singa

Business Acquisitions EMD Singapore, Additional Information (Details) - EMD Singapore $ in Millions	Oct. 04, 2013USD ($)
Business Acquisition [Line Items]
Percentage of voting interests acquired	100.00%
Consideration, gross	$ 4.9

Business Acquisitions EMD Sin67

Business Acquisitions EMD Singapore Purchase Price Allocation (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013	Oct. 04, 2013
Business Acquisition [Line Items]
Goodwill	$ 438,829	$ 321,077	$ 230,701
EMD Singapore
Business Acquisition [Line Items]
Current assets (excluding cash)				$ 300
Property, plant and equipment				154
Definite-lived intangible assets				1,885
Goodwill				2,659
Current liabilities				(64)
Total purchase price allocation				$ 4,934

Business Acquisitions EMD Sin68

Business Acquisitions EMD Singapore Breakout of Definite-Lived Intangible Assets (Details) - EMD Singapore $ in Thousands	Oct. 04, 2013USD ($)
Business Acquisition [Line Items]
Weighted average amortization life	8 years
Total purchase price allocation	$ 1,885
Client relationships
Business Acquisition [Line Items]
Definite-lived intangible assets	1,870
Other intangible assets
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 15
Weighted average amortization life	2 years

Business Acquisitions Vital Riv

Business Acquisitions Vital River, Additional Information (Details) $ in Thousands	Jan. 04, 2013USD ($)
Business Acquisition [Line Items]
Noncontrolling interest, ownership percentage by parent	75.00%
Redeemable noncontrolling interest percentage to acquire	25.00%
Vital River
Business Acquisition [Line Items]
Fair value of net assets acquired	$ 24,219
Cash acquired from acquisition	$ 2,700

Business Acquisitions Vital R70

Business Acquisitions Vital River Purchase Price Allocation (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013	Jan. 04, 2013
Business Acquisition [Line Items]
Goodwill	$ 438,829	$ 321,077	$ 230,701
Vital River
Business Acquisition [Line Items]
Current assets (excluding cash)				$ 3,092
Property, plant and equipment				10,468
Other long-term assets				2,242
Definite-lived intangible assets				16,954
Goodwill				16,989
Current liabilities				(11,303)
Long-term liabilities				(5,260)
Redeemable noncontrolling interest				(8,963)
Total purchase price allocation				$ 24,219

Business Acquisitions Vital R71

Business Acquisitions Vital River Breakout of Definite Lived Intangible Assets (Details) - Vital River $ in Thousands	Jan. 04, 2013USD ($)
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 16,954
Client relationships
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 14,741
Weighted average amortization life	12 years
Reacquired rights
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 2,053
Weighted average amortization life	1 year
Other intangible assets
Business Acquisition [Line Items]
Definite-lived intangible assets	$ 160
Weighted average amortization life	3 years

Supplemental Balance Sheet In72

Supplemental Balance Sheet Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Provision for doubtful accounts	$ 1.8	$ 0.5	$ 1.3
Depreciation expense	$ 70.7	$ 70.5	$ 78.8

Supplemental Balance Sheet In73

Supplemental Balance Sheet Information Trade Receivables, Net (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014
Trade Receivables, Net [Abstract]
Client receivables	$ 230,010	$ 219,118
Unbilled revenue	45,996	43,780
Total	276,006	262,898
Less: Allowance for doubtful accounts	5,938	4,907
Trade receivables, net	$ 270,068	$ 257,991

Supplemental Balance Sheet In74

Supplemental Balance Sheet Information Inventories (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014
Inventory Disclosure [Abstract]
Raw materials and supplies	$ 15,998	$ 15,416
Work in process	12,101	11,802
Finished products	65,636	61,825
Inventories	$ 93,735	$ 89,043

Supplemental Balance Sheet In75

Supplemental Balance Sheet Information Other Assets, Current (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Investments	$ 20,516	$ 16,167
Prepaid income tax	26,350	26,287
Restricted cash	271	2,552
Other	149	291
Other current assets	$ 47,286	$ 45,297

Supplemental Balance Sheet In76

Supplemental Balance Sheet Information Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014
Other Assets, Current [Line Items]
Gross property, plant and equipment	$ 1,322,772	$ 1,331,780
Less accumulated depreciation	(644,813)	(654,983)
Property, plant and equipment, net	677,959	676,797
Land
Other Assets, Current [Line Items]
Gross property, plant and equipment	39,846	40,314
Buildings
Other Assets, Current [Line Items]
Gross property, plant and equipment	713,841	682,495
Machinery and equipment
Other Assets, Current [Line Items]
Gross property, plant and equipment	362,695	384,713
Leasehold improvements
Other Assets, Current [Line Items]
Gross property, plant and equipment	41,477	37,270
Furniture and fixtures
Other Assets, Current [Line Items]
Gross property, plant and equipment	21,783	22,577
Vehicles
Other Assets, Current [Line Items]
Gross property, plant and equipment	3,819	3,967
Computer hardware and software
Other Assets, Current [Line Items]
Gross property, plant and equipment	113,466	119,474
Construction in progress
Other Assets, Current [Line Items]
Gross property, plant and equipment	$ 25,845	$ 40,970

Supplemental Balance Sheet In77

Supplemental Balance Sheet Information Other Assets, Noncurrent (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014
Other Assets, Noncurrent [Abstract]
Life insurance policies	$ 27,554	$ 27,603
Investment in limited partnerships	32,730	27,047
Restricted cash	1,745	0
Other	9,614	18,301
Other assets	$ 71,643	$ 72,951

Supplemental Balance Sheet In78

Supplemental Balance Sheet Information Other Liabilities, Current (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014
Other Liabilities, Current [Abstract]
Accrued income taxes	$ 12,168	$ 9,362
Other	376	233
Other current liabilities	$ 12,544	$ 9,595

Supplemental Balance Sheet In79

Supplemental Balance Sheet Information Other Liabilities, Noncurrent (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014
Other Liabilities Disclosure [Abstract]
Long-term pension liability	$ 34,604	$ 45,135
Accrued executive supplemental life insurance retirement plan and deferred compensation plan	30,188	33,007
Other	24,270	21,403
Other long-term liabilities	$ 89,062	$ 99,545

Investments in Limited Partne80

Investments in Limited Partnerships and Marketable Securities (Details) - USD ($)	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Marketable Securities and Equity-Method Affiliates [Abstract]
Income (loss) from limited partnerships	$ 3,823,000	$ 9,301,000	$ 5,864,000
Limited partnership, committed contribution	65,000,000
Limited partnership, committed funding	28,800,000
Limited partner, dividends	7,300,000	7,400,000	$ 0
Limited partnership, retained earnings	2,400,000	$ 4,600,000
Sales of available for sale securities	$ 0

Investments in Limited Partne81

Investments in Limited Partnerships and Marketable Securities Summary of Marketable Securities (Details)	12 Months Ended
	Dec. 26, 2015USD ($)
Schedule of Available-for-sale Securities [Line Items]
Sales of available for sale securities	$ 0
Amortized Cost	4,650,000
Gross Unrealized Gains	0
Gross Unrealized Losses	141,000
Fair Value	4,509,000
Mutual fund
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	4,650,000
Gross Unrealized Gains	0
Gross Unrealized Losses	141,000
Fair Value	$ 4,509,000

Fair Value Schedule of Fair Val

Fair Value Schedule of Fair Value (Details) - USD ($)	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers between fair value levels	$ 0	$ 0
Cash equivalents	190,000	1,934,000
Other current assets:
Marketable securities	4,509,000
Foreign currency forward contracts	15,000
Other assets:
Life insurance policies	20,364,000	20,520,000
Total assets measured at fair value	25,078,000	22,454,000
Other current liabilities:
Contingent consideration	1,172,000	1,583,000
Other long-term liabilities:
Contingent consideration	198,000	1,245,000
Redeemable noncontrolling interest	28,008,000	28,419,000
Total liabilities and redeemable noncontrolling interest measured at fair value	29,378,000	31,247,000
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Other current assets:
Marketable securities	4,509,000
Foreign currency forward contracts	0
Other assets:
Life insurance policies	0	0
Total assets measured at fair value	4,509,000	0
Other current liabilities:
Contingent consideration	0
Other long-term liabilities:
Contingent consideration	0	0
Redeemable noncontrolling interest	0	0
Total liabilities and redeemable noncontrolling interest measured at fair value	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	190,000	1,934,000
Other current assets:
Marketable securities	0
Foreign currency forward contracts	15,000
Other assets:
Life insurance policies	20,364,000	20,520,000
Total assets measured at fair value	20,569,000	22,454,000
Other current liabilities:
Contingent consideration	0
Other long-term liabilities:
Contingent consideration	0	0
Redeemable noncontrolling interest	0	0
Total liabilities and redeemable noncontrolling interest measured at fair value	0	0
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Other current assets:
Marketable securities	0
Foreign currency forward contracts	0
Other assets:
Life insurance policies	0	0
Total assets measured at fair value	0	0
Other current liabilities:
Contingent consideration	1,172,000	1,583,000
Other long-term liabilities:
Contingent consideration	198,000	1,245,000
Redeemable noncontrolling interest	28,008,000	28,419,000
Total liabilities and redeemable noncontrolling interest measured at fair value	$ 29,378,000	$ 31,247,000

Fair Value (Details)

Fair Value (Details) - USD ($)	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014
Fair Value Disclosures [Abstract]
Transfers between fair value levels	$ 0	$ 0
Fair value inputs, discount rate	18.00%
Percentage change in discount rate	1.00%
Change in fair value resulting from a 1% increase in discount rate	$ 1,700,000

Fair Value Schedule of Redeemab

Fair Value Schedule of Redeemable Noncontrolling Interest (Details) - Redeemable Noncontrolling Interest - Fair Value, Inputs, Level 3 - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Beginning balance	$ 28,419	$ 20,581
Additions	0	0
Total gains or losses (realized/unrealized):
Net income attributable to noncontrolling interest	838	855
Foreign currency translation	(1,066)	(442)
Change in fair value included in additional paid-in capital	(183)	7,425
Ending balance	$ 28,008	$ 28,419

Fair Value Schedule of Continge

Fair Value Schedule of Contingent Consideration (Details) - Contingent Consideration - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Beginning balance	$ 2,828	$ 0
Additions	973	2,678
Payments	(600)	0
Total gains or losses (realized/unrealized):
Reversal of previously recorded contingent liability and change in fair value	(1,831)	150
Ending balance	$ 1,370	$ 2,828

Goodwill and Other Intangible86

Goodwill and Other Intangible Assets Gross Carrying Amount and Accumulated Amoritzation of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Goodwill [Line Items]
Goodwill, gross	$ 1,443,829	$ 1,326,077	$ 1,235,701
Acquisitions
Transfers
Foreign Exchange
Goodwill	$ 438,829	$ 321,077	230,701
RMS
Goodwill [Line Items]
Goodwill, gross	58,167	59,196	83,551
Acquisitions	0	0
Transfers		(23,172)
Foreign Exchange	(1,029)	(1,183)
DSA
Goodwill [Line Items]
Goodwill, gross	1,252,050	1,234,302	1,152,150
Acquisitions	22,146	102,171
Transfers		(9,196)
Foreign Exchange	(4,398)	(10,823)
Accumulated impairment loss	(1,005,000)	(1,005,000)	(1,005,000)
Manufacturing
Goodwill [Line Items]
Goodwill, gross	133,612	32,579	$ 0
Acquisitions	105,567	0
Transfers		32,368
Foreign Exchange	$ (4,534)	$ 211

Goodwill and Other Intangible87

Goodwill and Other Intangible Assets Schedule of Intangible Assets, Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014
Finite-lived intangible assets
Gross	$ 137,124	$ 33,974
Accumulated Amortization	(69,694)	(19,938)
Net	67,430	14,036
Indefinite-lived intangibles	0	3,438
Total other intangible assets, net	67,430	17,474
Total intangible assets, net	280,804	178,875
Intangible assets previously assigned indefinite lives	$ 3,400
Useful life	20 years
Backlog
Finite-lived intangible assets
Gross	$ 50,568	8,728
Accumulated Amortization	(50,554)	(6,636)
Net	14	2,092
Technology
Finite-lived intangible assets
Gross	60,350	13,474
Accumulated Amortization	(5,911)	(4,166)
Net	54,439	9,308
Trademarks and trade names
Finite-lived intangible assets
Gross	11,495	6,603
Accumulated Amortization	(5,944)	(5,314)
Net	5,551	1,289
Other identifiable intangible assets
Finite-lived intangible assets
Gross	14,711	5,169
Accumulated Amortization	(7,285)	(3,822)
Net	7,426	1,347
Client relationships
Finite-lived intangible assets
Gross	396,537	379,339
Accumulated Amortization	(183,163)	(217,938)
Net	213,374	161,401
Total intangible assets, net	$ 213,374	$ 161,401

Goodwill and Other Intangible88

Goodwill and Other Intangible Assets (Amortization Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of intangible assets	$ 24,229	$ 25,957	$ 17,806
Estimated amortization expense for each of the next five fiscal years
2,016	26,835
2,017	26,678
2,018	24,434
2,019	21,617
2,020	$ 21,293

Long-Term Debt and Capital Le89

Long-Term Debt and Capital Lease Obligations (Long-Term Debt) (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014
Debt Instrument
Total debt	$ 836,234	$ 753,750
Less: current portion of long-term debt	(15,193)	(31,714)
Long-term debt	821,041	722,036
Debt discount and debt issuance costs	(6,805)	(5,401)
Long-term debt, net	814,236	716,635
Term loans
Debt Instrument
Total debt	390,000	378,000
Revolving credit facility
Debt Instrument
Total debt	446,041	375,536
Other long-term debt
Debt Instrument
Total debt	$ 193	$ 214

Long-Term Debt and Capital Le90

Long-Term Debt and Capital Lease Obligations (Additional Disclosures) (Details)	12 Months Ended
	Dec. 26, 2015USD ($)	Apr. 30, 2015USD ($)payment	Mar. 31, 2015USD ($)	Dec. 27, 2014USD ($)
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 1,300,000,000	$ 1,300,000,000	$ 970,000,000
Term loan facility		400,000,000
Line of credit facility, maximum borrowing facility		$ 900,000,000
Number of quarterly installment payments | payment		20
Debt, weighted average interest rate	1.33%			1.42%
EBITDA less capital expenditures to cash interest expense covenant ratio	3.5
Indebtedness to EBITDA covenant ratio	3.5
Capital lease obligations	$ 33,600,000			$ 1,000,000
Argenta and BioFocus UK | Financing Obligation
Debt Instrument [Line Items]
Capital lease obligations	35,800,000
Letter of Credit
Debt Instrument [Line Items]
Outstanding under letters of credit	$ 4,900,000			$ 5,000,000
Federal Funds Effective Swap Rate
Debt Instrument [Line Items]
Interest rate margin (as a percent)	0.50%
LIBOR
Debt Instrument [Line Items]
Interest rate margin (as a percent)	1.00%

Long-Term Debt and Capital Le91

Long-Term Debt and Capital Lease Obligations Principal Maturities of Long Term Debt (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014
Debt Disclosure [Abstract]
2,016	$ 15,193
2,017	22,500
2,018	32,500
2,019	50,000
2,020	716,041
Total	$ 836,234	$ 753,750

Equity and Redeemable Noncont92

Equity and Redeemable Noncontrolling Interest Earnings Per Share (Details) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Numerator:
Net income from continuing operations attributable to common shareholders	$ 150,263	$ 128,424	$ 104,093
Loss from discontinued operations, net of income taxes	(950)	(1,726)	(1,265)
Net income attributable to common shareholders	$ 149,313	$ 126,698	$ 102,828
Denominator:
Weighted-average shares outstanding—Basic	46,496	46,627	47,740
Effect of dilutive securities:
Stock options, restricted stock units, performance share units and restricted stock	1,138	931	749
Weighted-average shares outstanding—Diluted	47,634	47,558	48,489

Equity and Redeemable Noncont93

Equity and Redeemable Noncontrolling Interest Earnings Per Share, Additional Information (Details) - Employee Stock Option - shares shares in Millions	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	0.5	0.6	2.3
Weighted average number of shares outstanding, diluted	1.1	1.2	1.1

Equity and Redeemable Noncont94

Equity and Redeemable Noncontrolling Interest Treasury Stock (Details) - USD ($) shares in Millions	1 Months Ended	12 Months Ended
	Jul. 31, 2010	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013	Dec. 25, 2010
Treasury Shares and Accelerated Stock Repurchase Program (ASR)
Number of shares of common stock repurchased		0.1	0.1	0.1
Stock repurchase program, remaining authorized repurchase amount		$ 69,700,000
Purchase of treasury stock		117,478,000	$ 122,018,000	$ 165,932,000
2010 Share Repurchase Program
Treasury Shares and Accelerated Stock Repurchase Program (ASR)
Stock repurchase program, authorized amount increase (decrease)	$ 500,000,000		$ 150,000,000	$ 250,000,000	$ 250,000,000
Authorized amount of stock repurchase		$ 1,150,000,000
Open market repurchases
Treasury Shares and Accelerated Stock Repurchase Program (ASR)
Number of shares of common stock repurchased		1.5	2.1	3.5
Total cost of repurchase of treasury shares		$ 108,800,000	$ 110,600,000	$ 165,700,000
Purchase of treasury stock		$ 8,700,000	$ 6,800,000	$ 4,600,000

Equity and Redeemable Noncont95

Equity and Redeemable Noncontrolling Interest Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Stockholders' Equity Note [Abstract]
Accumulated other comprehensive income (loss), foreign currency translation adjustment, beginning balance	$ (19,891)	$ 28,503
Accumulated other comprehensive income (loss), pension and other post-retirement benefit plans, beginning balance	(54,356)	(23,146)
Other comprehensive loss before reclassifications, foreign currency translation and other	(60,745)	(48,499)
Other comprehensive loss, pension and other post-retirement benefit plans	(302)	(42,236)
Other comprehensive loss, total	(61,047)	(90,735)
Amounts reclassified from accumulated other comprehensive income (loss), foreign current translation and other	(2,341)	0
Amounts reclassified from accumulated other comprehensive income (loss), pension and other post-retirement benefit plans	2,617	1,234
Amounts reclassified from accumulated other comprehensive income (loss), total	276	1,234
Net current period other comprehensive income (loss), foreign currency translation and other	(63,086)	(48,499)
Net current period other comprehensive income (loss), pension and other post-retirement benefit plans	2,315	(41,002)
Net current period other comprehensive income (loss), total	(60,771)	(89,501)
Income tax benefit (expense), pension and other post-retirement benefit plans	0	105
Income tax benefit (expense), foreign currency translation and other	(530)	9,792
Income tax benefit (expense), total	(530)	9,897
Accumulated other comprehensive income (loss), foreign currency translation adjustment, ending balance	(82,977)	(19,891)
Accumulated other comprehensive income (loss), pension and other post-retirement benefit plans, ending balance	(52,571)	(54,356)
Accumulated other comprehensive income (Loss)	$ (135,548)	$ (74,247)	$ 5,357

Income Taxes Components of Inco

Income Taxes Components of Income from Continuing Operations Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Income from continuing operations before income taxes:
U.S.	$ 76,157	$ 71,002	$ 39,900
Non-U.S.	119,271	106,593	98,427
Income from continuing operations, before income taxes	195,428	177,595	138,327
Current:
Federal	23,687	13,733	10,832
Foreign	8,572	20,364	18,370
State	6,819	4,746	4,240
Total current	39,078	38,843	33,442
Deferred:
Federal	1,790	12,982	5,468
Foreign	3,064	(4,672)	(6,431)
State	(541)	518	432
Total deferred	4,313	8,828	(531)
Provision for income taxes	$ 43,391	$ 47,671	$ 32,911

Income Taxes Deferred Taxes (De

Income Taxes Deferred Taxes (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014
Deferred tax assets:
Compensation	$ 55,259	$ 49,702
Accruals and reserves	8,941	7,061
Inventory reserves and valuations	2,022	1,940
Financing related	902	993
Net operating loss and credit carryforwards	35,233	39,927
Other	2,593	4,426
Valuation allowance	(6,112)	(5,866)
Total deferred tax assets	98,838	98,183
Deferred tax liabilities:
Goodwill and other intangibles	(73,208)	(52,029)
Depreciation related	(23,664)	(23,549)
Investments in limited partnerships	(3,570)	(4,067)
Foreign withholding taxes	(6,590)	0
Total deferred tax liabilities:	(107,032)	(79,645)
Net deferred taxes	$ (8,194)
Net deferred taxes		$ 18,538

Income Taxes Reconciliation of

Income Taxes Reconciliation of US Statutory Tax Rate and Effective Tax Rate (Details)	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Income Tax Disclosure [Abstract]
U.S. statutory income tax rate	35.00%	35.00%	35.00%
Foreign tax rate differences	(8.60%)	(9.40%)	(8.00%)
State income taxes, net of Federal tax benefit	1.90%	1.90%	1.60%
Research tax credits and enhanced deductions	(2.60%)	(4.10%)	(6.60%)
Enacted tax rate changes	(1.50%)	0.00%	(0.40%)
Impact of tax uncertainties	(5.20%)	(0.70%)	1.00%
Foreign withholding taxes	3.40%	0.00%	0.00%
Impact of acquisitions and restructuring	(2.00%)	1.60%	0.20%
Other	1.80%	2.50%	1.00%
Effective tax rate	22.20%	26.80%	23.80%

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014
Income Tax Contingency [Line Items]
Unrecognized tax benefits, decrease resulting from acquisition	$ 10,400
Unrecognized tax benefits, increase resulting from acquisition	9,800
Valuation allowance, deferred tax asset, change	(200)
Valuation allowance, deferred tax asset	6,112	$ 5,866
Unrecognized tax benefits, period increase (decrease)	(11,300)
Unrecognized tax benefits that would impact effective tax rate	20,100	32,300
Change unrecognized tax benefits that, if recognized, would affect the effective tax rate.	12,200
Decrease in unrecognized tax benefits that is reasonably possible	1,900
Unrecognized tax benefits, interest on income taxes accrued	1,000	1,400
Undistributed earnings of foreign subsidiaries	547,600
Foreign withholding taxes, consolidated appropriations act	6,600
Foreign Tax Authority
Income Tax Contingency [Line Items]
Operating loss carryforwards	34,600	$ 39,800
Foreign Tax Authority | Net Operating Loss Carryforward, Expiring after 2015
Income Tax Contingency [Line Items]
Operating loss carryforwards	4,300
Foreign Tax Authority | Net Operating Loss Carryforward, Carried Forward Indefinitely
Income Tax Contingency [Line Items]
Operating loss carryforwards	11,600
Canada | Tax Credit Carryforwards,Expiring in 2030
Income Tax Contingency [Line Items]
Tax credit carryforward	$ 18,700

Income Taxes Change in Tax Posi

Income Taxes Change in Tax Positions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Reconciliation of unrecognized tax benefits
Beginning balance	$ 34,627	$ 18,475	$ 30,996
Additions to tax positions for current year	2,362	1,700	2,009
Additions to tax positions for prior years	3,028	18,502	1,709
Reductions to tax positions for current year	0	0	0
Reductions to tax positions for prior years	(3,991)	(3,722)	(732)
Settlements	(1,946)	(308)	(15,246)
Expiration of statute of limitations	(10,742)	(20)	(261)
Ending balance	$ 23,338	$ 34,627	$ 18,475

Employee Benefit Plans (Details

Employee Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Defined Contribution Plans Disclosure [Line Items]
Minimum deferral requirement	3 years
Maximum annual contributions per employee, percent	10.00%
Life insurance policies	$ 27,554	$ 27,603
Accumulated benefit obligation	$ 900	1,200
Sensitivity of expected rate of return on plan assets, percent change	0.50%
Sensitivity of change in expected rate of return, annual pension expense amount	$ 1,400
Employer contributions	5,900
Estimated future employer contributions	$ 4,500
Consecutive years of compensation for annual benefits under the ESLIRP plan	5 years
Equity Securities
Defined Contribution Plans Disclosure [Line Items]
Defined benefit plan, target plan asset allocations	44.30%
Fixed Income Securities
Defined Contribution Plans Disclosure [Line Items]
Defined benefit plan, target plan asset allocations	31.10%
Other Securities
Defined Contribution Plans Disclosure [Line Items]
Defined benefit plan, target plan asset allocations	24.60%
Pension Plans
Defined Contribution Plans Disclosure [Line Items]
Costs associated with defined contribution plan	$ 5,300	4,900	$ 4,700
Deferred Compensation Plan and Executive Supplemental Life Insurance Retirement Plan
Defined Contribution Plans Disclosure [Line Items]
Costs associated with defined contribution plan	$ 2,600	$ 3,300	$ 3,300

Employee Benefit Plans (Obligat

Employee Benefit Plans (Obligations and Funded Status) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Change in fair value of plan assets:
Employer contributions	$ 5,900
Pension Plans
Change in projected benefit obligations:
Benefit obligation at beginning of year	326,884	$ 286,212
Service cost	3,437	3,397	$ 3,368
Interest cost	11,912	12,822	11,273
Benefit payments	(7,517)	(9,002)
Actuarial loss (gain)	(11,783)	50,550
Administrative expenses paid	(411)	(459)
Effect of foreign exchange	(12,213)	(16,636)
Benefit obligation at end of year	310,309	326,884	286,212
Change in fair value of plan assets:
Fair value of plan assets at beginning of year	281,290	272,659
Actual return on plan assets	6,263	25,630
Employer contributions	6,088	6,874
Premiums paid	(411)	(459)
Effect of foreign exchange	(10,233)	(14,412)
Fair value of plan assets at end of year	275,480	281,290	272,659
Net balance sheet liability	34,829	45,594
Amounts recognized in balance sheet:
Noncurrent assets	261	61
Current liabilities	149	169
Noncurrent liabilities	34,941	45,486
Other Post-Retirement Benefit Plans
Change in projected benefit obligations:
Benefit obligation at beginning of year	32,246	29,498
Service cost	856	758	643
Interest cost	1,062	1,009	708
Benefit payments	(674)	(722)
Actuarial loss (gain)	1,421	1,703
Administrative expenses paid	0	0
Effect of foreign exchange	0	0
Benefit obligation at end of year	34,911	32,246	29,498
Change in fair value of plan assets:
Fair value of plan assets at beginning of year	0	0
Actual return on plan assets	0	0
Employer contributions	674	722
Premiums paid	0	0
Effect of foreign exchange	0	0
Fair value of plan assets at end of year	0	0	$ 0
Net balance sheet liability	34,911	32,246
Amounts recognized in balance sheet:
Noncurrent assets	0	0
Current liabilities	5,984	744
Noncurrent liabilities	$ 28,927	$ 31,502

Employee Benefit Plans (Accumul

Employee Benefit Plans (Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014
Pension Plans
Amounts recognized in accumulated other comprehensive income (loss)
Net actuarial loss	$ 66,499	$ 73,433
Net prior service cost (credit)	(4,584)	(5,388)
Net amount recognized	61,915	68,045
Other Post-Retirement Benefit Plans
Amounts recognized in accumulated other comprehensive income (loss)
Net actuarial loss	6,913	5,761
Net prior service cost (credit)	0	0
Net amount recognized	$ 6,913	$ 5,761

Employee Benefit Plans Benefit

Employee Benefit Plans Benefit Plan Obligations Compared to Plan Assets (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014
Pension Plans
Plans with Accumulated Benefit Obligations in Excess of Plan Assets
Accumulated benefit obligation	$ 275,849	$ 299,127
Fair value of plan assets	253,225	267,026
Other Post-Retirement Benefit Plans
Plans with Accumulated Benefit Obligations in Excess of Plan Assets
Accumulated benefit obligation	30,584	29,994
Fair value of plan assets	$ 0	$ 0

Employee Benefit Plans Projecte

Employee Benefit Plans Projected Benefit Obligation and Fair Value of Plan Assets (Details) - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ 301,244	$ 326,731
Fair value of plan assets	266,154	281,075
Other Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	34,911	32,246
Fair value of plan assets	$ 0	$ 0

Employee Benefit Plans Amounts

Employee Benefit Plans Amounts in Accumulated Other Comprehensive Income Expected to be Recognized as Components of Net Periodic Benefit Cost in Next Year (Details) $ in Thousands	12 Months Ended
	Dec. 26, 2015USD ($)
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Amortization of net actuarial loss	$ 1,931
Amortization of net prior service credit	(576)
Other Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Amortization of net actuarial loss	251
Amortization of net prior service credit	$ 0

Employee Benefit Plans (Compone

Employee Benefit Plans (Components of Net Period Benefit Cost) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 3,437	$ 3,397	$ 3,368
Interest cost	11,912	12,822	11,273
Expected return on plan assets	(16,987)	(17,444)	(14,672)
Amortization of prior service cost (credit)	(581)	961	2,711
Amortization of net loss (gain)	2,929	(637)	(603)
Net periodic cost (benefit)	710	(901)	2,077
Other Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	856	758	643
Interest cost	1,062	1,009	708
Expected return on plan assets	0	0	0
Amortization of prior service cost (credit)	0	250	249
Amortization of net loss (gain)	269	660	660
Net periodic cost (benefit)	$ 2,187	$ 2,677	$ 2,260

Employee Benefit Plans (Assumpt

Employee Benefit Plans (Assumptions) (Details)	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Pension Plans
Weighted-average assumptions used to determine benefit obligations
Discount rate	3.93%	3.79%
Rate of compensation increase	3.19%	3.19%
Weighted-average assumptions used to determine net periodic benefit cost
Discount rate	3.79%	4.54%	4.13%
Expected long-term return on plan assets	6.24%	6.41%	6.27%
Rate of compensation increase	3.19%	3.39%	3.04%
Other Post-Retirement Benefit Plans
Weighted-average assumptions used to determine benefit obligations
Discount rate	3.56%	3.34%
Rate of compensation increase	3.00%	3.00%
Weighted-average assumptions used to determine net periodic benefit cost
Discount rate	3.34%	3.47%	2.63%
Expected long-term return on plan assets	0.00%	0.00%	0.00%
Rate of compensation increase	3.00%	3.00%	2.50%

Employee Benefit Plans (Plan As

Employee Benefit Plans (Plan Assets) (Details) - Pension Plans - USD ($) $ in Thousands	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 275,480	$ 281,290	$ 272,659
Cash
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	92	1
Equity securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	71,831	85,818
Debt securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	71,311	72,948
Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	129,414	120,409
Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,832	2,114
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	199,181	217,785
Level 1 | Cash
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	92	1
Level 1 | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	65,890	80,692
Level 1 | Debt securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	68,489	69,716
Level 1 | Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	63,689	67,079
Level 1 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,021	297
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	74,537	61,734
Level 2 | Cash
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Level 2 | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5,941	5,126
Level 2 | Debt securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,822	3,232
Level 2 | Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	65,725	53,330
Level 2 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	49	46
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,762	1,771
Level 3 | Cash
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Level 3 | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Level 3 | Debt securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Level 3 | Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Level 3 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 1,762	$ 1,771

Employee Benefit Plans (Estimat

Employee Benefit Plans (Estimated Future Benefit Payments) (Details) $ in Thousands	Dec. 26, 2015USD ($)
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
2,016	$ 7,561
2,017	7,914
2,018	8,361
2,019	8,926
2,020	9,379
Thereafter	52,917
Other Post-Retirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
2,016	6,087
2,017	747
2,018	734
2,019	722
2,020	709
Thereafter	$ 24,480

Stock-Based Compensation (Detai

Stock-Based Compensation (Details) - USD ($)	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under plan	6,300,000
Shares based compensation, shares equivalent	1
Share based compensation, plan modification, incremental compensation cost	$ 4,500,000
Capitalized share-based compensation related costs	0	$ 0	$ 0
Pool of excess tax benefits	22,300,000	10,800,000	$ 7,300,000
Adjustments to additional paid in capital, income tax deficiency from share-based compensation	$ 10,600,000	4,300,000
Windfall tax benefit		$ 1,600,000
Weighted-average grant date fair value of stock options granted (in dollars per share)	$ 17.24	$ 15.19	$ 11.17
Stock-based compensation related to PSUs	$ 40,122,000	$ 31,035,000	$ 24,542,000
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under plan	18,700,000
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to unvested stock options expected to vest	11,200,000
Weighted average vesting period of unvested stock options expected to vest	2 years 2 months
Intrinsic value of options exercised	$ 28,300,000	$ 30,500,000	$ 24,700,000
Employee Stock Option | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting period	4 years	4 years	4 years
Stock options, expiration period	5 years	5 years	5 years
Employee Stock Option | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, expiration period	7 years	7 years	7 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares based compensation, shares equivalent	2.3
Weighted average vesting period of unvested stock options expected to vest	1 year 1 month
Unrecognized compensation cost related to unvested restricted stock units expected to vest	$ 20,200,000
Fair value of restricted stock and stock units vested	$ 15,700,000	$ 13,900,000	$ 15,100,000
Restricted Stock | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting period	2 years	2 years	2 years
Restricted Stock | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting period	4 years	4 years	4 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of restricted stock and stock units vested	$ 6,600,000
Maximum number of common shares to be issued upon vesting of PSUs	800,000
Stock-based compensation related to PSUs	$ 14,700,000	$ 8,500,000	$ 2,200,000
Weighted average per share fair value (in dollars per share)	$ 76.67
Performance Shares | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting period	3 years	3 years	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Per Employee Available to Purchase	0	0	0
Performance condition only | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PSUs granted (in shares)	15,000

Stock based Compensation Expens

Stock based Compensation Expense Allocation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation	$ 40,122	$ 31,035	$ 24,542
Provision for income taxes	(14,225)	(11,006)	(8,658)
Stock-based compensation, net of income taxes	25,897	20,029	15,884
Cost of revenue (excluding amortization of intangible assets)
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation	6,511	5,382	5,381
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation	$ 33,611	$ 25,653	$ 19,161

Stock-Based Compensation Stock

Stock-Based Compensation Stock Options (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
trading day average stock price on grant date	20 days
2007 Incentive Plan | Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding, balance at the beginning of the period (in shares)	2,553
Options outstanding, weighted average exercise price (in dollars per share)	$ 50.62	$ 43.39
Options granted (in shares)	474
Options granted (in dollars per share)	$ 76.33
Options exercised (in shares)	(909)
Options exercised (in dollars per share)	$ 43.34
Options canceled (in shares)	(52)
Options canceled (in dollars per share)	$ 55.78
Options outstanding, balance at the end of the period (in shares)	2,066	2,553
Options outstanding weighted average remaining contractual life	3 years 8 months
Options outstanding, aggregate intrinsic value	$ 60,846
Options exercisable, balance at the end of the period (in shares)	834
Options exercisable, balance at the end of the period (in dollars per share)	$ 37.88
Options exercisable, weighted average remaining contractual life	2 years 7 months
Options exercisable, aggregate intrinsic value	$ 35,200
Options expected to vest (in shares)	1,219
Options expected to vest (in dollars per share)	$ 59.21
Options expected to vest, weighted average remaining contractual life	4 years 5 months
Options expected to vest, aggregate intrinsic value	$ 25,448

Stock-Based Compensation Sto114

Stock-Based Compensation Stock Options, Assumptions Used in Calculation of Fair Value (Details)	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Expected life (in years)	3 years 7 months	4 years 2 months	4 years 2 months 12 days
Expected volatility	28.00%	29.50%	32.70%
Risk-free interest rate	1.10%	1.50%	0.80%
Expected dividend yield	0.00%	0.00%	0.00%

Stock-Based Compensation Restri

Stock-Based Compensation Restricted Stock and Restricted Stock Units (Details) - 2007 Incentive Plan - Restricted Stock and Restricted Stock Units - $ / shares shares in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Balance at the beginning of the period (in shares)	803
Balance, weighted average grant date fair value (in dollars per share)	$ 55.52	$ 44.67
PSUs granted (in shares)	198
Weighted average per share fair value (in dollars per share)	$ 76.16
Vested (in shares)	(365)
Vested (in dollars per share)	$ 42.95
Canceled (in shares)	(29)
Canceled (in dollars per share)	$ 54.08
Balance at the end of the period (in shares)	607	803

Stock-Based Compensation Perfor

Stock-Based Compensation Performance Based Stock Award Program (Details) - $ / shares	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Key Assumptions:
Expected volatility	28.00%	29.50%	32.70%
Risk-free interest rate	1.10%	1.50%	0.80%
Expected dividend yield	0.00%	0.00%	0.00%
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average per share fair value (in dollars per share)	$ 76.67
Key Assumptions:
Expected volatility	23.00%	29.00%	32.00%
Risk-free interest rate	0.96%	0.63%	0.38%
Expected dividend yield	0.00%	0.00%	0.00%
20 trading day average stock price on grant date	$ 0.206	$ 0.131	$ 0.069
2007 Incentive Plan | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average per share fair value (in dollars per share)	$ 88.62	$ 67.82	$ 44.47
Performance and Market conditions | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PSUs granted (in shares)	148,900	214,823	163,847

Foreign Currency Contracts- Not

Foreign Currency Contracts- Notational Amount and Fair Value Disclosure (Details) - Foreign Exchange Contract $ in Thousands	Dec. 26, 2015USD ($)
Derivative [Line Items]
Other current assets, notational value	$ 88,483
Other Current Assets
Derivative [Line Items]
Other current assets, fair value	$ 15

Foreign Currency Contracts Effe

Foreign Currency Contracts Effect on Statement of Income (Details) $ in Thousands	12 Months Ended
	Dec. 26, 2015USD ($)
Derivatives, Fair Value [Line Items]
Derivative, maturity	3 months
Other income (expense), net | Foreign Exchange Contract
Derivatives, Fair Value [Line Items]
Gain (Loss) Recognized	$ (4,917)

Commitments and Contingencie119

Commitments and Contingencies (Details) $ in Millions	1 Months Ended	12 Months Ended
	Jul. 31, 2015patent	Dec. 26, 2015USD ($)	Dec. 27, 2014USD ($)	Dec. 28, 2013USD ($)
Commitments and Contingencies Disclosure [Abstract]
Rent expense from operating leases		$ 23.4	$ 14.2	$ 16.7
Maximum insurance deductibles		5
Government Billing
Litigation [Line Items]
Loss contingency, estimate of possible loss		$ 1.5
Pending Litigation | Idexx
Litigation [Line Items]
Patents allegedly infringed, number | patent	3

Commitments and Contingencies M

Commitments and Contingencies Minimum Rental Commitments Under Non-Cancelable Leases (Details) $ in Thousands	Dec. 26, 2015USD ($)
Commitments and Contingencies Disclosure [Abstract]
2,016	$ 19,702
2,017	17,841
2,018	12,009
2,019	9,783
2,020	7,969
Thereafter	18,086
Total	$ 85,390

Segment and Geographic Infor121

Segment and Geographic Information Financial Information by Reportable Business Segment (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 26, 2015	Sep. 26, 2015	Jun. 27, 2015	Mar. 28, 2015	Dec. 27, 2014	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Segment Reporting Information [Line Items]
Revenue	$ 353,850	$ 349,465	$ 339,573	$ 320,414	$ 329,548	$ 327,567	$ 341,179	$ 299,368	$ 1,363,302	$ 1,297,662	$ 1,165,528
Operating income	$ 52,269	$ 55,440	$ 55,735	$ 43,005	$ 40,767	$ 46,172	$ 51,025	$ 39,706	206,449	177,670	151,401
Depreciation and amortization									94,881	96,445	96,636
Capital expenditures									63,252	56,925	39,154
RMS
Segment Reporting Information [Line Items]
Revenue									473,230	507,327	511,350
Operating income									121,447	121,376	116,737
Depreciation and amortization									22,688	27,512	41,837
Capital expenditures									17,398	18,749	16,717
DSA
Segment Reporting Information [Line Items]
Revenue									612,173	538,218	432,378
Operating income									121,981	69,749	47,413
Depreciation and amortization									46,812	47,138	37,720
Capital expenditures									30,333	19,759	12,561
Manufacturing
Segment Reporting Information [Line Items]
Revenue									277,899	252,117	221,800
Operating income									74,201	78,620	61,227
Depreciation and amortization									17,967	14,092	17,079
Capital expenditures									$ 9,814	$ 15,541	$ 9,876

Segment and Geographic Infor122

Segment and Geographic Information Reconciliation of Segment Operating Income and Capital Expenditures (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 26, 2015	Sep. 26, 2015	Jun. 27, 2015	Mar. 28, 2015	Dec. 27, 2014	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Segment Reporting Information [Line Items]
Operating Income	$ 52,269	$ 55,440	$ 55,735	$ 43,005	$ 40,767	$ 46,172	$ 51,025	$ 39,706	$ 206,449	$ 177,670	$ 151,401
Capital expenditures									63,252	56,925	39,154
Total reportable segments
Segment Reporting Information [Line Items]
Operating Income									317,629	269,745	225,377
Capital expenditures									57,545	54,049	39,154
Unallocated corporate
Segment Reporting Information [Line Items]
Operating Income									(111,180)	(92,075)	(73,976)
Capital expenditures									$ 5,707	$ 2,876	$ 0

Segment and Geographic Infor123

Segment and Geographic Information Revenue by Product and Service Offering (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 26, 2015	Sep. 26, 2015	Jun. 27, 2015	Mar. 28, 2015	Dec. 27, 2014	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Segment Reporting Information [Line Items]
Total revenue	$ 353,850	$ 349,465	$ 339,573	$ 320,414	$ 329,548	$ 327,567	$ 341,179	$ 299,368	$ 1,363,302	$ 1,297,662	$ 1,165,528
RMS
Segment Reporting Information [Line Items]
Total revenue									473,230	507,327	511,350
DSA
Segment Reporting Information [Line Items]
Total revenue									612,173	538,218	432,378
Manufacturing
Segment Reporting Information [Line Items]
Total revenue									$ 277,899	$ 252,117	$ 221,800

Segment and Geographic Infor124

Segment and Geographic Information Unallocated Corporate Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Segment Reporting Information [Line Items]
Stock-based compensation	$ 40,122	$ 31,035	$ 24,542
Depreciation expense	70,700	70,500	78,800
Corporate
Segment Reporting Information [Line Items]
Stock-based compensation	25,751	18,474	13,411
Salary, bonus and fringe	33,026	30,838	23,446
Consulting, audit and professional services	15,418	13,431	8,666
IT related expenses	8,400	6,528	11,646
Depreciation expense	7,414	7,703	6,334
Acquisition related adjustments	11,644	6,285	1,752
Other general unallocated corporate expenses	9,527	8,816	8,721
Total unallocated corporate overhead costs	$ 111,180	$ 92,075	$ 73,976

Segment and Geographic Infor125

Segment and Geographic Information Revenue and Capital Assets by Geographic Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Segment Reporting Information [Line Items]
Revenue	$ 1,363,302	$ 1,297,662	$ 1,165,528
Long-lived assets	677,959	676,797	738,146
U.S.
Segment Reporting Information [Line Items]
Revenue	659,466	588,531	551,340
Long-lived assets	402,238	386,624	447,829
Europe
Segment Reporting Information [Line Items]
Revenue	435,491	446,263	353,688
Long-lived assets	159,445	153,203	130,855
Canada
Segment Reporting Information [Line Items]
Revenue	172,349	163,490	162,404
Long-lived assets	77,535	95,272	109,811
Japan
Segment Reporting Information [Line Items]
Revenue	40,520	49,921	59,370
Long-lived assets	22,348	23,896	30,589
Other Non-U.S.
Segment Reporting Information [Line Items]
Revenue	55,476	49,457	38,726
Long-lived assets	$ 16,393	$ 17,802	$ 19,062

Selected Quarterly Financial126

Selected Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 26, 2015	Sep. 26, 2015	Jun. 27, 2015	Mar. 28, 2015	Dec. 27, 2014	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Selected Quarterly Financial Data [Abstract]
Total revenue	$ 353,850	$ 349,465	$ 339,573	$ 320,414	$ 329,548	$ 327,567	$ 341,179	$ 299,368	$ 1,363,302	$ 1,297,662	$ 1,165,528
Gross profit	140,574	138,075	132,783	119,660	119,945	118,268	125,634	108,813
Operating income	52,269	55,440	55,735	43,005	40,767	46,172	51,025	39,706	206,449	177,670	151,401
Net income attributable to common shareholders	$ 31,884	$ 37,379	$ 48,509	$ 31,541	$ 27,166	$ 32,036	$ 35,264	$ 32,232	$ 149,313	$ 126,698	$ 102,828
Basic:
Continuing operations attributable to common shareholders (in dollars per share)	$ 0.71	$ 0.81	$ 1.04	$ 0.67	$ 0.60	$ 0.70	$ 0.76	$ 0.69	$ 3.23	$ 2.76	$ 2.18
Discontinued operations (in dollars per share)	(0.02)	0	0	0	(0.02)	0	(0.01)	(0.01)	(0.02)	(0.04)	(0.03)
Net income attributable to common shareowners (in dollars per share)	0.69	0.81	1.04	0.67	0.58	0.70	0.75	0.68	3.21	2.72	2.15
Diluted:
Continuing operations attributable to common shareowners (in dollars per share)	0.69	0.79	1.02	0.66	0.59	0.68	0.75	0.67	3.15	2.70	2.15
Discontinued operations (in dollars per share)	(0.02)	0	0	0	(0.02)	0	(0.01)	(0.01)	(0.02)	(0.04)	(0.03)
Net income attributable to common shareowners (in dollars per share)	$ 0.67	$ 0.79	$ 1.02	$ 0.66	$ 0.57	$ 0.68	$ 0.74	$ 0.67	$ 3.13	$ 2.66	$ 2.12

Subsequent Events (Details)

Subsequent Events (Details) - WIL Research - Subsequent Event $ in Millions	Jan. 06, 2016USD ($)
Subsequent Event [Line Items]
Total purchase price allocation	$ 585
Proceeds from Lines of Credit	350
Loss on contract termination	$ 17.5