Charles River Laboratories International (CRL) 10-K 11 Feb 20 2019 FY Annual report Financial data

Cover Page

Cover Page - USD ($)	12 Months Ended
	Dec. 28, 2019	Jan. 24, 2020	Jun. 29, 2019
Cover page.
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 28, 2019
Document Transition Report	false
Entity File Number	001-15943
Entity Registrant Name	CHARLES RIVER LABORATORIES INTERNATIONAL, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	06-1397316
Entity Address, Address Line One	251 Ballardvale Street
Entity Address, City or Town	Wilmington
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	01887
City Area Code	781
Local Phone Number	222-6000
Title of 12(b) Security	Common stock, $0.01 par value
Trading Symbol	CRL
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Smaller Reporting Company	false
Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 6,796,882,148
Entity Common Stock, Shares Outstanding		48,959,576
Documents Incorporated by Reference	Portions of the registrant’s definitive Proxy Statement for its 2020 Annual Meeting of Shareholders scheduled to be held on May 6, 2020 , which will be filed with the Securities and Exchange Commission (SEC) not later than 120 days after December 28, 2019 , are incorporated by reference into Part III of this Annual Report on Form 10-K. With the exception of the portions of the 2020 Proxy Statement expressly incorporated into this Annual Report on Form 10-K by reference, such document shall not be deemed filed as part of this Form 10-K.
Entity Central Index Key	0001100682
Current Fiscal Year End Date	--12-28
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Amendment Flag	false

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Total revenue	$ 2,621,226	$ 2,266,096	$ 1,857,601
Costs and expenses:
Selling, general and administrative	517,622	443,854	371,266
Amortization of intangible assets	89,538	64,830	41,370
Operating income	351,151	331,383	288,282
Other income (expense):
Interest income	1,522	812	690
Interest expense	(60,882)	(63,772)	(29,777)
Other income, net	12,293	13,258	37,760
Income from continuing operations, before income taxes	304,084	281,681	296,955
Provision for income taxes	50,023	54,463	171,369
Income from continuing operations, net of income taxes	254,061	227,218	125,586
Income (loss) from discontinued operations, net of income taxes	0	1,506	(137)
Net income	254,061	228,724	125,449
Less: Net income attributable to noncontrolling interests	2,042	2,351	2,094
Net income attributable to common shareholders	$ 252,019	$ 226,373	$ 123,355
Basic:
Continuing operations attributable to common shareholders (in dollars per share)	$ 5.17	$ 4.69	$ 2.60
Discontinued operations (in dollars per share)	0	0.03	0
Net income attributable to common shareholders (in dollars per share)	5.17	4.72	2.60
Diluted:
Continuing operations attributable to common shareholders (in dollars per share)	5.07	4.59	2.54
Discontinued operations (in dollars per share)	0	0.03	0
Net income attributable to common shareholders (in dollars per share)	$ 5.07	$ 4.62	$ 2.54
Weighted-average shares outstanding—Basic (in shares)	48,730	47,947	47,481
Weighted-average shares outstanding—Diluted (in shares)	49,693	49,018	48,564
Service
Total revenue	$ 2,029,371	$ 1,687,941	$ 1,298,298
Costs and expenses:
Cost of services provided and products sold	1,371,699	1,150,371	867,014
Product
Total revenue	591,855	578,155	559,303
Costs and expenses:
Cost of services provided and products sold	$ 291,216	$ 275,658	$ 289,669

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 254,061	$ 228,724	$ 125,449
Other comprehensive income (loss):
Foreign currency translation adjustment and other	14,224	(28,305)	78,084
Pension and other post-retirement benefit plans (Note 12):
Prior service cost and (losses) gains arising during the period	(25,165)	(1,659)	36,593
Amortization of net loss and prior service benefit included in net periodic cost for pension and other post-retirement benefit plans	1,772	2,477	3,344
Comprehensive income, before income taxes	244,892	201,237	243,470
Less: Income tax (benefit) expense related to items of other comprehensive income (Note 10)	(3,633)	(1,892)	7,954
Comprehensive income, net of income taxes	248,525	203,129	235,516
Less: Comprehensive income related to noncontrolling interests, net of income taxes	1,822	1,398	3,128
Comprehensive income attributable to common shareholders, net of income taxes	$ 246,703	$ 201,731	$ 232,388

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Current assets:
Cash and cash equivalents	$ 238,014	$ 195,442
Trade receivables, net	514,033	472,248
Inventories	160,660	127,892
Prepaid assets	52,588	53,447
Other current assets	56,030	48,807
Total current assets	1,021,325	897,836
Property, plant and equipment, net	1,044,128	932,877
Operating lease right-of-use assets, net	140,085
Goodwill	1,540,565	1,247,133
Client relationships and other intangible assets, net	689,413	610,888
Deferred tax assets	44,659	23,386
Other assets	212,615	143,759
Total assets	4,692,790	3,855,879
Current liabilities:
Current portion of long-term debt and finance leases	38,545	31,416
Accounts payable	111,498	66,250
Accrued compensation	158,617	137,212
Deferred revenue	171,805	145,139
Accrued liabilities	139,118	106,925
Other current liabilities	90,598	71,280
Total current liabilities	710,181	558,222
Long-term debt, net and finance leases	1,849,666	1,636,598
Operating lease right-of-use liabilities	116,252
Deferred tax liabilities	167,283	143,635
Other long-term liabilities	182,933	179,121
Total liabilities	3,026,315	2,517,576
Commitments and contingencies
Redeemable noncontrolling interests	28,647	18,525
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; 48,936 shares issued and 48,936 shares outstanding as of December 28, 2019 and 48,210 shares issued and 48,209 shares outstanding as of December 29, 2018	489	482
Additional paid-in capital	1,531,785	1,447,512
Retained earnings	280,329	42,096
Treasury stock, at cost, 0 and 1 share as of December 28, 2019 and December 29, 2018, respectively	0	(55)
Accumulated other comprehensive loss	(178,019)	(172,703)
Total equity attributable to common shareholders	1,634,584	1,317,332
Noncontrolling interest	3,244	2,446
Total equity	1,637,828	1,319,778
Total liabilities, redeemable noncontrolling interests and equity	4,692,790	3,855,879
Client relationships, net
Current assets:
Client relationships and other intangible assets, net	613,573	537,945
Other intangible assets, net
Current assets:
Client relationships and other intangible assets, net	$ 75,840	$ 72,943

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 28, 2019	Dec. 29, 2018
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	20,000,000	20,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	120,000,000	120,000,000
Common stock, shares issued (in shares)	48,936,000	48,210,000
Common Stock, shares outstanding (in shares)	48,936,000	48,209,000
Treasury stock, shares (in shares)	0	1,000

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Cash flows relating to operating activities
Net income	$ 254,061	$ 228,724	$ 125,449
Less: Income (loss) from discontinued operations, net of income taxes	0	1,506	(137)
Income from continuing operations, net of income taxes	254,061	227,218	125,586
Adjustments to reconcile net income from continuing operations to net cash provided by operating activities:
Depreciation and amortization	198,095	161,779	131,159
Stock-based compensation	57,271	47,346	44,003
Deferred income taxes	(21,895)	(9,702)	28,254
Gain on venture capital investments	(20,706)	(15,928)	(22,867)
Gain on divestiture	0	0	(10,577)
Impairment charges	0	0	17,239
Other, net	7,931	15,613	(666)
Changes in assets and liabilities:
Trade receivables, net	(8,323)	(21,196)	(48,279)
Inventories	(21,399)	(13,338)	(17,838)
Accounts payable	29,775	(12,732)	34
Accrued compensation	3,394	31,616	3,666
Long-term payable on Transition Tax (Notes 5 and 11)	0	(8,974)	61,038
Deferred revenue	(3,620)	36,072	(8,466)
Customer contract deposits	(10,898)	28,115	0
Other assets and liabilities, net	17,250	(24,749)	15,788
Net cash provided by operating activities	480,936	441,140	318,074
Cash flows relating to investing activities
Acquisition of businesses and assets, net of cash acquired	(515,701)	(824,868)	(25,012)
Capital expenditures	(140,514)	(140,054)	(82,431)
Purchases of investments and contributions to venture capital investments	(22,341)	(25,125)	(46,217)
Proceeds from sale of investments	942	35,849	9,128
Proceeds from divestiture	0	0	72,462
Other, net	(3,888)	(805)	(516)
Net cash used in investing activities	(681,502)	(955,003)	(72,586)
Cash flows relating to financing activities
Proceeds from long-term debt and revolving credit facility	3,358,461	2,755,028	236,856
Proceeds from exercises of stock options	34,546	37,657	38,870
Payments on long-term debt, revolving credit facility, and finance lease obligations	(3,124,588)	(2,201,003)	(372,435)
Payments on debt financing costs	(6,593)	(18,337)	0
Purchase of treasury stock	(18,087)	(13,846)	(106,909)
Other, net	(11,802)	(1,440)	(4,858)
Net cash provided by (used in) financing activities	231,937	558,059	(208,476)
Discontinued operations
Net cash used in operating activities from discontinued operations	0	(3,735)	(1,809)
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	11,357	(9,474)	11,234
Net change in cash, cash equivalents, and restricted cash	42,728	30,987	46,437
Cash, cash equivalents, and restricted cash, beginning of period	197,318	166,331	119,894
Cash, cash equivalents, and restricted cash, end of period	240,046	197,318	166,331
Supplemental cash flow information:
Cash, cash equivalents, and restricted cash, end of period	240,046	166,331	166,331
Cash paid for income taxes	54,060	67,600	60,377
Cash paid for interest	67,813	47,540	27,417
Non-cash investing and financing activities:
Additions to property, plant and equipment, net	21,447	18,212	38,199
Assets acquired under finance leases	$ 4,819	$ 1,473	$ 722

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock	Total Equity Attributable to Common Shareholders	Noncontrolling Interest
Beginning balance (in shares) at Dec. 31, 2016		86,301				38,938
Beginning balance at Dec. 31, 2016	$ 839,125	$ 863	$ 2,477,371	$ 165,303	$ (253,764)	$ (1,553,005)	$ 836,768	$ 2,357
Increase (Decrease) in Stockholders' Equity
Net income	124,534			123,355			123,355	1,179
Other comprehensive income (loss)	109,033				109,033		109,033
Dividends declared to noncontrolling interest	(1,209)							(1,209)
Issuance of stock under employee compensation plans (in shares)		1,194
Issuance of stock under employee compensation plans	38,830	$ 12	38,818				38,830
Acquisition of treasury shares (in shares)						1,155
Acquisition of treasury shares	(106,909)					$ (106,909)	(106,909)
Stock-based compensation	44,003		44,003				44,003
Ending balance (in shares) at Dec. 30, 2017		87,495				40,093
Ending balance at Dec. 30, 2017	1,047,407	$ 875	2,560,192	288,658	(144,731)	$ (1,659,914)	1,045,080	2,327
Increase (Decrease) in Stockholders' Equity
Net income	227,923			226,373			226,373	1,550
Other comprehensive income (loss)	(24,642)				(24,642)		(24,642)
Reclassification due to adoption of ASU 2018-02	3,330
Reclassification due to adoption of ASU 2018-02 | Accounting Standards Update 2018-02	0			3,330	(3,330)
Dividends declared to noncontrolling interest	(1,431)							(1,431)
Adjustment of redeemable noncontrolling interest to fair value	(2,069)		(2,069)				(2,069)
Issuance of stock under employee compensation plans (in shares)		936
Issuance of stock under employee compensation plans	37,666	$ 9	37,657				37,666
Acquisition of treasury shares (in shares)						129
Acquisition of treasury shares	$ (13,846)					$ (13,846)	(13,846)
Retirement of treasury shares (in shares)	(40,200)	(40,221)				(40,221)
Retirement of treasury shares	$ (1,700,000)	$ (402)	(1,195,614)	(477,689)		$ 1,673,705
Stock-based compensation	47,346		47,346				47,346
Ending balance (in shares) at Dec. 29, 2018		48,210				1
Ending balance at Dec. 29, 2018	1,319,778	$ 482	1,447,512	42,096	(172,703)	$ (55)	1,317,332	2,446
Increase (Decrease) in Stockholders' Equity
Net income	254,103			252,019			252,019	2,084
Other comprehensive income (loss)	(5,316)				(5,316)		(5,316)
Dividends declared to noncontrolling interest	(1,286)							(1,286)
Adjustment of redeemable noncontrolling interest to fair value	(1,451)		(1,451)				(1,451)
Purchase of additional equity interest in and modification of Vital River redeemable noncontrolling interest	(1,870)		(1,870)				(1,870)
Issuance of stock under employee compensation plans (in shares)		866
Issuance of stock under employee compensation plans	34,686	$ 8	34,678				34,686
Acquisition of treasury shares (in shares)						139
Acquisition of treasury shares	$ (18,087)					$ (18,087)	(18,087)
Retirement of treasury shares (in shares)	(100)	(140)				(140)
Retirement of treasury shares	$ (18,100)	$ (1)	(4,355)	(13,786)		$ 18,142
Stock-based compensation	57,271		57,271				57,271
Ending balance (in shares) at Dec. 28, 2019		48,936				0
Ending balance at Dec. 28, 2019	$ 1,637,828	$ 489	$ 1,531,785	$ 280,329	$ (178,019)	$ 0	$ 1,634,584	$ 3,244

DESCRIPTION OF BUSINESS AND SUM

DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 28, 2019
Organization, Consolidation and Presentation of Financial Statements [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, that enable the Company to support its clients from target identification through non-clinical 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 year is typically based on 52-week s , with each quarter comp osed of 13 weeks ending on the last Saturday on, or closest to, March 31, June 30, September 30, and December 31. Segment Reporting The Company reports its results in three reportable segments: Research Models and Services (RMS), Discovery and Safety Assessment (DSA), and Manufacturing Support (Manufacturing). The Company’s RMS reportable segment includes the Research Models and Research Model Services businesses. Research Models includes the commercial production and sale of small research models, as well as the supply of large research models. Research Model Services includes: Genetically Engineered Models and Services (GEMS), which performs contract breeding and other services associated with genetically engineered models; Research Animal Diagnostic Services (RADS), which provides health monitoring and diagnostics services related to research models; and Insourcing Solutions (IS), which provides colony management of its clients’ research operations (including recruitment, training, staffing, and management services). The Company’s DSA reportable segment includes services required to take a drug through the early development process including discovery services, which are non-regulated services to assist clients with the identification, screening, and selection of a lead compound for drug development, and regulated and non-regulated (GLP and non-GLP) safety assessment services. The Company’s Manufacturing reportable segment includes Microbial Solutions, which provides in vitro (non-animal) lot-release testing products, microbial detection products, and species identification services; Biologics Testing Services (Biologics), which performs specialized testing of biologics; Avian Vaccine Services (Avian), which supplies specific-pathogen-free chicken eggs and chickens; and contract development and manufacturing (CDMO) services, which, until the Company divested this business on February 10, 2017, allowed it to provide formulation design and development, manufacturing, and analytical and stability testing for small molecules. 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 make 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, Cash Equivalents, and Investments Cash equivalents include money market funds, time deposits and other investments with remaining maturities at the purchase date of three months or less. Time deposits with original maturities of greater than three months are reported as short term 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 in fiscal years 2019 , 2018 , or 2017 or trade receivables as of December 28, 2019 or December 29, 2018 . 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 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 and 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 market prices determined through third-party pricing services; • Foreign currency forward contracts - Valued using market observable inputs, such as forward foreign exchange points and foreign exchanges rates; • Life insurance policies - Valued at cash surrender value based on the fair value of underlying investments; • Debt instruments - The book value of the Company’s term and revolving loans, which are variable rate loans carried at amortized cost, approximates the fair value based on current market pricing of similar debt. The book value of the Company’s 5.5% Senior Notes due in 2026 and the 4.25% Senior Notes due in 2028 (Senior Notes), which are fixed rate debt, are carried at amortized cost. Fair value of the Senior Notes is based on quoted market prices and on borrowing rates available to the Company; and • Contingent consideration - Valued based on a probability weighting of the future cash flows associated with the potential outcomes. Inventories The Company’s inventories consist of raw materials, work in process and finished product related primarily to small models, large models, microbial solutions products, and avian related eggs and flocks. Inventories are stated at the lower of cost or net realizable value. Inventory value is generally based on the standard cost method for all businesses except for the Avian business, which is based on an average cost. Standard costs are trued-up to reflect actual cost . For small models inventory, costs include 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 models inventory, costs are primarily the external cost paid to acquire the model. For the microbial solutions inventory, costs include direct materials, cost of personnel directly involved in the manufacturing and assembly of products sold, and an allocation of facility overhead. For the avian related inventory, costs include direct materials, such as animal feed, cost of personnel directly involved with the care of the eggs and flocks, and an allocation of facility overhead. 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, 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 follow: 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. Finance lease assets are amortized over the lease term, however, if ownership is transferred by the end of the finance lease, or there is a bargain purchase option, such finance 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 The Company accounts for business combinations 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, which typically represents a significant portion of the purchase price. The determination of the fair value of intangible assets requires the use of significant judgment using management’s best estimates of inputs and assumptions that a market participant would use. Significant judgments include (i) the fair value; and (ii) whether such intangible assets are amortizable or non-amortizable and, if the former, the period and the method by which the intangible asset will be amortized. The Company utilizes commonly accepted valuation techniques, such as the income approach and the cost approach, as appropriate, in establishing the fair value of intangible assets. Typically, key assumptions include projections of cash flows that arise from identifiable intangible assets of acquired businesses as well as discount rates based on an analysis of the weighted average cost of capital, adjusted for specific risks associated with the assets. In recent acquisitions, customer relationship intangible assets (also referred to as client relationships) are the most significant identifiable asset acquired. To determine the fair value of the acquired client relationships, the Company typically utilizes the multiple period excess earnings model (a commonly accepted valuation technique), which relies on the following key assumptions: projections of cash flows from the acquired entities, which includes future revenue growth rates, operating income margins, and customer attrition rates; as well as discount rates based on an analysis of the acquired entities’ weighted average cost of capital. 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 the 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 7, “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 acquisition 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 amortized over the pattern in which the economic benefits of the intangible assets are utilized and 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. Venture Capital Investments The Company invests in several venture capital funds that invest in start-up companies, primarily in the life sciences industry. The Company’s ownership interest in these funds ranges from less than 1% to approximately 12% . The Company accounts for the investments in limited partnerships (LPs), which are variable interest entities, under the equity method of accounting. For publicly-held investments in the LPs, the Company adjusts for changes in fair market value based on reported share holdings at the end of each fiscal quarter. The Company is not the primary beneficiary because it has no power to direct the activities that most significantly affect the LPs’ economic performance. The Company accounts for the investments in limited liability companies, which are not variable interest entities, under the equity method of accounting. Under the equity method of accounting, the Company’s 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, net in the accompanying consolidated statements of income. 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 are based on information from the fund’s management team, market prices of known public holdings of the fund and other information. Other Investments The Company invests in equity of certain privately-held companies, primarily with minority positions. These investments are reported at fair value or under the equity method of accounting, as appropriate. Equity investments that do not have readily determinable fair values are generally recorded at cost, plus or minus certain adjustments. 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. The Company held 44 and 45 contracts at December 28, 2019 and December 29, 2018 , with a face value of $72.7 million and $65.2 million , respectively. Leases At inception of a contract, the Company determines if a contract meets the definition of a lease. A lease is a contract, or part of a contract, that conveys the right to control the use of identified property, plant, or equipment (an identified asset) for a period of time in exchange for consideration. The Company determines if the contract conveys the right to control the use of an identified asset for a period of time. The Company assesses throughout the period of use whether the Company has both of the following: (1) the right to obtain substantially all of the economic benefits from use of the identified asset, and (2) the right to direct the use of the identified asset. This determination is reassessed if the terms of the contract are changed. Leases are classified as operating or finance leases based on the terms of the lease agreement and certain characteristics of the identified asset. Right-of-use assets and lease liabilities are recognized at lease commencement date based on the present value of the minimum future lease payments. The Company leases laboratory, production, and office space (real estate), as well as land, vehicles and certain equipment under non-cancellable operating and finance leases. The carrying value of the Company’s right-of-use lease assets is substantially concentrated in its real estate leases, while the volume of lease agreements is primarily concentrated in vehicles and equipment leases. The Company’s policy is to not record leases with an original term of twelve months or less on the consolidated balance sheets. The Company recognizes lease expense for these short-term leases on a straight-line basis over the lease term. Certain lease agreements include rental payments that are adjusted periodically for inflation or other variables. In addition to rent, the leases may require the Company to pay additional amounts for taxes, insurance, maintenance and other expenses, which are generally referred to as non-lease components. Such adjustments to rental payments and variable non-lease components are treated as variable lease payments and recognized in the period in which the obligation for these payments was incurred. Variable lease components and variable non-lease components are not measured as part of the right-of-use asset and liability. Only when lease components and their associated non-lease components are fixed are they accounted for as a single lease component and are recognized as part of a right-of-use asset and liability. Total contract consideration is allocated to the combined fixed lease and non-lease component. This policy election applies consistently to all asset classes under lease agreements. Most leases contain clauses for renewal at the Company’s option with renewal terms that generally extend the lease term from 1 to 5 years . Certain lease agreements contain options to purchase the leased property and options to terminate the lease. Payments to be made in option periods are recognized as part of the right-of-use lease assets and lease liabilities when it is reasonably certain that the option to extend the lease will be exercised or the option to terminate the lease will not be exercised, or is not at the Company’s option. The Company determines whether the reasonably certain threshold is met by considering contract-, asset-, market-, and entity-based factors. A portfolio approach is applied to certain lease contracts with similar characteristics. The Company’s lease agreements do not contain any significant residual value guarantees or material restrictive covenants imposed by the leases. The Company subleases a limited number of lease arrangements. Sublease activity is not material to the consolidated financial statements. Stock-Based Compensation The Company may grant stock options, restricted stock, restricted stock units (RSUs), and performance share units (PSUs) to employees and stock options, restricted stock, and RSUs to non-employee directors under stock-based compensation plans. Stock-based compensation is recognized as an expense in the consolidated statements of income based on the grant date fair value, adjusted for forfeitures when they occur, over the requisite service period. For stock options, restricted stock and RSUs 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 and a portion of the award continues to vest after the employee’s eligible 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 RSUs is based on the market value of the Company’s common stock on the date of grant. Revenue Recognition Accounting Standard Codification Topic 606, “Revenue from Contracts with Customers” (ASC 606) became effective for the Company on December 31, 2017 and was adopted using the modified retrospective method for all contracts not completed as of the date of adoption. For contracts that were modified before the effective date, the Company reflected the aggregate effect of all modifications when identifying performance obligations and allocating transaction price in accordance with the practical expedient, which did not have a material effect on the cumulative impact of adopting ASC 606. The reported results for fiscal years 2019 and 2018 reflect the application of ASC 606 guidance while the historical results for fiscal year 2017 was prepared under the guidance of ASC 605, “Revenue Recognition” (ASC 605). There is no material difference in the reporting of revenue during fiscal years 2019 and 2018 in accordance with ASC 606 when compared to fiscal year 2017 in accordance with ASC 605. Revenue is recognized when, or as, obligations under the terms of a contract are satisfied, which occurs when control of the promised products or services is transferred to customers. Revenue is measured as the amount of consideration the Company expects to receive in exchange for transferring products or services to a customer (“transaction price”). To the extent the transaction price includes variable consideration, the Company estimates the amount of variable consideration that should be included in the transaction price utilizing the amount to which the Company expects to be entitled. Variable consideration is included in the transaction price if, in the Company’s judgment, it is probable that a significant future reversal of cumulative revenue under the contract will not occur. Estimates of variable consideration and determination of whether to include estimated amounts in the transaction price are based largely on an assessment of the Company’s anticipated performance and all information (historical, current and forecasted) that is reasonably available. Sales, value add, and other taxes collected on behalf of third parties are excluded from revenue. When determining the transaction price of a contract, an adjustment is made if payment from a customer occurs either significantly before or significantly after performance, resulting in a significant financing component. Generally, the Company does not extend payment terms beyond one year. Applying the practical expedient, the Company does not assess whether a significant financing component exists if the period between when the Company performs its obligations under the contract and when the customer pays is one year or less. The Company’s contracts do not generally contain significant financing components. Contracts with customers may contain multiple performance obligations. For such arrangements, the transaction price is allocated to each performance obligation based on the estimated relative standalone selling prices of the promised products or services underlying each performance obligation. The Company determines standalone selling prices based on the price at which the performance obligation is sold separately. If the standalone selling price is not observable through past transactions, the Company estimates the standalone selling price taking into account available information such as market conditions and internally approved pricing guidelines related to the performance obligations. Contracts are often modified to account for changes in contract specifications and requirements. Contract modifications exist when the modification either creates new, or changes existing, enforceable rights and obligations. Generally, when contract modifications create new performance obligations, the modification is considered to be a separate contract and revenue is recognized prospectively. When contract modifications change existing performance obligations, the existing transaction price and measure of progress for the performance obligation to which it relates is generally recognized as an adjustment to revenue (either as an increase in or a reduction of revenue) on a cumulative catch-up basis. Product revenue is generally recognized when the customer obtains control of the Company’s product, which occurs at a point in time, and may be upon shipment or upon delivery based on the contractual shipping terms of a contract. Service revenue is generally recognized over time as the services are delivered to the customer based on the extent of progress towards completion of the performance obligation. The selection of the method to measure progress towards completion requires judgment and is based on the nature of the products or services to be provided. Depending on which better depicts the transfer of value to the customer, the Company generally measures its progress using either cost-to-cost (input method) or right-to-invoice (output method). The Company uses the cost-to-cost measure of progress when it best depicts the transfer of value to the customer which occurs as the Company incurs costs on its contract, generally related to fixed fee service contracts. Under the cost-to-cost measure of progress, the extent of progress towards completion is measured based on the ratio of costs incurred to date to the total estimated costs at completion of the performance obligation. The costs calculation includes variables such as labor hours, allocation of overhead costs, research model costs, and subcontractor costs. Revenue is recorded proportionally as costs are incurred. The right-to-invoice measure of progress is generally related to rate per unit contracts, as the extent of progress towards completion is measured based on discrete service or time-based increments, such as samples tested or labor hours incurred. Revenue is recorded in the amount invoiced since that amount corresponds directly to the value of the Company’s perfo

BUSINESS COMBINATIONS AND DIVES

BUSINESS COMBINATIONS AND DIVESTITURE	12 Months Ended
	Dec. 28, 2019
Business Combinations [Abstract]
BUSINESS COMBINATIONS AND DIVESTITURE	BUSINESS COMBINATIONS AND DIVESTITURE HemaCare Corporation On January 3, 2020, the Company acquired HemaCare Corporation (HemaCare), a business specializing in the production of human-derived cellular products for the cell therapy market. The acquisition of HemaCare will expand the Company’s comprehensive portfolio of early-stage research and manufacturing support solutions to encompass the production and customization of high-quality, human derived cellular products to better support clients’ cell therapy programs. The preliminary purchase price of HemaCare was approximately $380 million in cash. The acquisition was funded through a combination of cash on hand and proceeds from the Company’s Credit Facility under the multi-currency revolving facility. See Note 9, “Long-Term Debt and Finance Leases.” This business will be reported as part of the Company’s RMS reportable segment. Due to the limited time between the acquisition date and the filing of this Annual Report on Form 10-K, it is not practicable for the Company to disclose the preliminary allocation of the purchase price to assets acquired and liabilities assumed. The Company incurred transaction and integration costs in connection with the acquisition of $3.3 million during fiscal year 2019, which were included in Selling, general and administrative expenses within the consolidated statements of income. Citoxlab On April 29, 2019 , the Company acquired Citoxlab, a non-clinical CRO, specializing in regulated safety assessment services, non-regulated discovery services, and medical device testing. With operations in Europe and North America, the acquisition of Citoxlab further strengthens the Company’s position as a leading, global, early-stage CRO by expanding its scientific portfolio and geographic footprint, which enhances the Company’s ability to partner with clients across the drug discovery and development continuum. The preliminary purchase price for Citoxlab was $527.7 million in cash, subject to certain post-closing adjustments that may change the purchase price. The acquisition was funded through a combination of cash on hand and proceeds from the Company’s Credit Facility under the multi-currency revolving facility. This business is reported as part of the Company’s DSA reportable segment. The preliminary purchase allocation of $491.0 million , net of $36.7 million of cash acquired was as follows: April 29, 2019 (in thousands) Trade receivables (contractual amount of $35,405) $ 35,405 Inventories 5,282 Other current assets (excluding cash) 13,917 Property, plant and equipment 88,605 Goodwill 280,711 Definite-lived intangible assets 162,400 Other long-term assets 20,163 Deferred revenue (15,278 ) Current liabilities (46,081 ) Deferred tax liabilities (27,458 ) Other long-term liabilities (22,624 ) Redeemable noncontrolling interest (4,035 ) Total purchase price allocation $ 491,007 The preliminary purchase price allocation is subject to change as additional information becomes available concerning the fair value and tax basis of the assets acquired and liabilities assumed, including certain contracts and obligations. 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. From the date of the acquisition through December 28, 2019 , the Company recorded measurement-period adjustments related to the acquisition that resulted in an immaterial change to the purchase price allocation on a consolidated basis. 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 $ 134,600 13 Developed technology 19,900 3 Backlog 7,900 1 Total definite-lived intangible assets $ 162,400 12 The goodwill resulting from the transaction, $7.2 million of which is deductible for tax purposes due to a prior asset acquisition, is primarily attributable to the potential growth of the Company’s DSA business from customers introduced through Citoxlab and the assembled workforce of the acquired business. The Company incurred transaction and integration costs in connection with the acquisition of $20.7 million during fiscal year 2019 , which were primarily included in Selling, general and administrative expenses within the consolidated statements of income. Beginning on April 29, 2019, Citoxlab has been included in the operating results of the Company. Citoxlab revenue and operating income from April 29, 2019 through December 28, 2019 was $123.7 million and $6.2 million , respectively. The following selected unaudited pro forma consolidated results of operations are presented as if the Citoxlab acquisition had occurred as of the beginning of the period immediately preceding the period of acquisition, which is December 31, 2017, after giving effect to certain adjustments. For fiscal year 2019 , these adjustments included additional amortization of intangible assets and depreciation of fixed assets of $5.7 million , additional interest expense on borrowings of $1.2 million , elimination of intercompany activity and other one-time costs, and the tax impacts of these adjustments. For fiscal year 2018 , these adjustments included additional amortization of intangible assets and depreciation of fixed assets of $9.4 million , additional interest expense on borrowings of $4.1 million , elimination of intercompany activity and other one-time costs, and the tax impacts of these adjustments. Fiscal Year 2019 2018 (in thousands) (unaudited) Revenue $ 2,683,610 $ 2,442,283 Net income attributable to common shareholders 268,995 233,288 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 dates indicated or that may result in the future. No effect has been given for synergies, if any, that may be realized through the acquisition. MPI Research On April 3, 2018 , the Company acquired MPI Research, a non-clinical CRO providing comprehensive testing services to biopharmaceutical and medical device companies worldwide. The acquisition enhances the Company’s position as a leading global early-stage CRO by strengthening its ability to partner with clients across the drug discovery and development continuum. The purchase price for MPI Research was $829.7 million in cash. The acquisition was funded by borrowings on the Credit Facility as well as the issuance of the Company’s 2026 Senior Notes. See Note 9, “Long-Term Debt and Finance Lease Obligations.” This business is reported as part of the Company’s DSA reportable segment. The purchase allocation of $800.8 million , net of $27.7 million of cash acquired and a final net working capital adjustment of $1.2 million , was as follows: April 3, 2018 (in thousands) Trade receivables (contractual amount of $35,073) $ 35,073 Inventories 4,463 Other current assets (excluding cash) 5,893 Property, plant and equipment 128,403 Goodwill 441,656 Definite-lived intangible assets 309,200 Other long-term assets 1,081 Deferred revenue (23,926 ) Current liabilities (32,885 ) Deferred tax liabilities (65,945 ) Other long-term liabilities (2,213 ) Total purchase price allocation $ 800,800 From the date of the acquisition through March 30, 2019, the Company recorded measurement-period adjustments related to the acquisition that resulted in an immaterial change to the purchase price allocation on a consolidated basis. No further adjustments will be made to the purchase price allocation. 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 $ 264,900 13 Developed technology 23,400 3 Backlog 20,900 1 Total definite-lived intangible assets $ 309,200 12 The goodwill resulting from the transaction, $4.1 million of which is deductible for tax purposes due to a prior asset acquisition, is primarily attributable to the potential growth of the Company’s DSA business from customers introduced through MPI Research and the assembled workforce of the acquired business. No significant integration costs were incurred in connection with the acquisition for fiscal year 2019 . The Company incurred transaction and integration costs in connection with the acquisition of $16.5 million during fiscal year 2018, which were primarily included in Selling, general and administrative expenses within the consolidated statements of income. MPI Research revenue and operating income from April 3, 2018 through December 29, 2018 was $209.5 million and $33.4 million , respectively. Beginning on April 3, 2018 , MPI Research 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 MPI Research acquisition had occurred as of the beginning of the period immediately preceding the period of acquisition, which is January 1, 2017, after giving effect to certain adjustments. For fiscal year 2018 , these adjustments included additional amortization of intangible assets and depreciation of fixed assets of $14.1 million , additional interest expense on borrowings of $2.8 million , elimination of intercompany activity and other one-time costs, and the tax impacts of these adjustments. For fisc al year 2017 , these adjustments included additional amortization of intangible assets and depreciation of fixed assets of $22.4 million , additional interest expense on borrowings of $27.1 million , elimination of intercompany activity and other one-time costs, and the tax impacts of these adjustments. Fiscal Year 2018 2017 (in thousands) (unaudited) Revenue $ 2,328,213 $ 2,095,385 Net income attributable to common shareholders 225,550 126,641 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 dates indicated or that may result in the future. No effect has been given for synergies, if any, that may be realized through the acquisition. KWS BioTest Limited On January 11, 2018 , the Company acquired KWS BioTest Limited (KWS BioTest), a CRO specializing in in vitro and in vivo discovery testing services for immuno-oncology, inflammatory and infectious diseases. The acquisition enhances the Company’s discovery expertise, with complementary offerings that provide the Company’s customers with additional tools in the active therapeutic research areas of oncology and immunology. The purchase price for KWS BioTest was $20.3 million in cash, and was funded by the Company’s various borrowings. In addition to the initial purchase price, the transaction included aggregate, undiscounted contingent payments of up to £ 3.0 million based on future performance. The terms of these contingent payments were amended during fiscal year 2018, resulting in a fixed payment of £ 2.0 million or $2.6 million , which was paid during the first quarter of fiscal year 2019. The KWS BioTest business is reported as part of the Company’s DSA reportable segment. The purchase price allocation of $21.5 million , net of $1.0 million of cash acquired and a final net working capital adjustment of $0.4 million , was as follows: January 11, 2018 (in thousands) Trade receivables (contractual amount of $1,309) $ 1,309 Other current assets (excluding cash) 99 Property, plant and equipment 1,136 Definite-lived intangible assets - client relationships 3,647 Goodwill 17,660 Current liabilities (1,575 ) Deferred revenue (151 ) Long-term liabilities (596 ) Total purchase price allocation $ 21,529 From the date of the acquisition through December 29, 2018, the Company recorded measurement-period adjustments related to the acquisition that resulted in an immaterial change to the purchase price allocation on a consolidated basis. No further adjustments will be made to the purchase price allocation. The only definite-lived intangible asset relates to client relationships, which will be amortized over a weighted average life of 12 years. The goodwill resulting from the transaction is primarily attributable to the potential growth of the Company’s DSA business from customers introduced through KWS BioTest and the assembled workforce of the acquired business. The goodwill attributable to KWS BioTest is not deductible for tax purposes. No significant integration costs were incurred in connection with the acquisition during fiscal year 2019 . The Company incurred transaction and integration costs in connection with the acquisition of $0.7 million during fiscal year 2018, which were included in Selling, general and administrative expenses within the consolidated statements of income. Pro forma financial information as well as actual revenue and operating income (loss) have not been included because KWS BioTest’s financial results are not significant when compared to the Company’s consolidated financial results. Brains On-Line On August 4, 2017 , the Company acquired Brains On-Line, a CRO providing critical data that advances novel therapeutics for the treatment of central nervous system (CNS) diseases. Brains On-Line strategically expands the Company’s existing CNS capabilities and establishes the Company as a single-source provider for a broad portfolio of discovery CNS services. The purchase price for Brains On-Line was $21.3 million in cash and was funded by the Company’s various borrowings. In addition to the initial purchase price, the transaction included aggregate, undiscounted contingent payments of up to €6.7 million based on future performance. During the first quarter of fiscal year 2019, the terms of these contingent payments were amended, resulting in a fixed payment of $2.6 million , which was paid during the three months ended June 29, 2019. The Brains On-Line business is reported as part of the Company’s DSA reportable segment. The purchase price allocation of $20.1 million , net of $0.6 million of cash acquired, was as follows: August 4, 2017 (in thousands) Trade receivables (contractual amount of $1,146) $ 1,146 Other current assets (excluding cash) 640 Property, plant and equipment 664 Other long-term assets 29 Definite-lived intangible assets 9,300 Goodwill 12,582 Current liabilities (1,683 ) Deferred revenue (405 ) Long-term liabilities (2,151 ) Total purchase price allocation $ 20,122 From the date of the acquisition through June 30, 2018, the Company recorded measurement-period adjustments related to the acquisition that resulted in an immaterial change to the purchase price allocation on a consolidated basis. No further adjustments will be made to the purchase price allocation. 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 $ 7,000 13 Other intangible assets 2,300 10 Total definite-lived intangible assets $ 9,300 12 The goodwill resulting from the transaction is primarily attributable to the potential growth of the Company’s DSA businesses from customers and technology introduced through Brains On-Line and the assembled workforce of the acquired business. The goodwill attributable to Brains On-Line is not deductible for tax purposes. No significant integration costs were incurred in connection with the acquisition during fiscal years 2019 or 2018. The Company incurred transaction and integration costs in connection with the acquisition of $2.6 million during fiscal year 2017, which were included in selling, general and administrative expenses within the consolidated statements of income. Pro forma financial information as well as actual revenue and operating income (loss) have not been included because Brains On-Line’s financial results are not significant when compared to the Company’s consolidated financial results. Other Acquisition On August 28, 2019 , the Company acquired an 80% ownership interest in a supplier that supports the Company’s DSA reportable segment. The remaining 20% interest is a redeemable non-controlling interest. See Note 10, “Equity and Noncontrolling Interests.” The preliminary purchase price was $23.4 million , net of a $4.0 million pre-existing relationship for a supply agreement settled upon acquisition, and subject to certain post-closing adjustments that may change the purchase price. The acquisition was funded through a combination of cash on hand and proceeds from the Company’s Credit Facility under the multi-currency revolving facility. The business is reported as part of the Company’s DSA reportable segment. The preliminary purchase allocation of $23.1 million , net of $0.3 million of cash acquired was as follows: August 28, 2019 (in thousands) Trade receivables (contractual amount of $189) $ 189 Inventories 7,644 Property, plant and equipment 1,462 Goodwill 12,669 Other long-term assets 11,849 Current liabilities (441 ) Deferred tax liabilities (1,331 ) Other long-term liabilities (238 ) Redeemable noncontrolling interest (8,740 ) Total purchase price allocation $ 23,063 The purchase price allocation is subject to change as additional information becomes available concerning the fair value and tax basis of the assets acquired and liabilities assumed, including certain contracts and obligations. 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. From the date of the acquisition through December 28, 2019 , the Company recorded measurement-period adjustments related to the acquisition that resulted in an immaterial change to the purchase price allocation on a consolidated basis. The Company incurred transaction and integration costs in connection with the acquisition of $3.6 million for fiscal year 2019 which are primarily included in Selling, general and administrative expenses within the consolidated statements of income. Pro forma financial information as well as the disclosure of actual results have not been included because these financial results are not significant when compared to the Company’s consolidated financial results. Contract Manufacturing On February 10, 2017, the Company sold its CDMO business to Quotient Clinical Ltd., based in London, England, for $75 million in proceeds, net of $0.6 million in cash and cash equivalents transferred in conjunction with the sale and $0.3 million of working capital adjustments. The CDMO business was acquired in April 2016 as part of the acquisition of WIL Research and was reported in the Company’s Manufacturing reportable segment. The Company determined that the CDMO business was not optimized within the Company’s portfolio at its current scale, and that the capital could be better deployed in other long-term growth opportunities. During the three months ended April 1, 2017, the Company recorded a gain on the divestiture of the CDMO business of $10.6 million , which was included in other income, net within the Company’s consolidated statements of income. The carrying amounts of the major classes of assets and liabilities associated with the divestiture of the CDMO business were as follows: February 10, 2017 (in thousands) Assets Current assets $ 5,505 Property, plant and equipment, net 11,174 Goodwill 35,857 Long-term assets 17,154 Total assets $ 69,690 Liabilities Deferred revenue $ 4,878 Other current liabilities 1,158 Total liabilities $ 6,036

REVENUE FROM CONTRACTS WITH CUS

REVENUE FROM CONTRACTS WITH CUSTOMERS	12 Months Ended
	Dec. 28, 2019
Revenue from Contract with Customer [Abstract]
REVENUE FROM CONTRACTS WITH CUSTOMERS	REVENUE FROM CONTRACTS WITH CUSTOMERS Disaggregation of Revenue The following tables disaggregate the Company’s revenue by major business line and timing of transfer of products or services: Major Products/Service Lines: 2019 2018 (in thousands) RMS $ 537,089 $ 519,682 DSA 1,618,995 1,316,854 Manufacturing 465,142 429,560 Total revenue $ 2,621,226 $ 2,266,096 Timing of Revenue Recognition: 2019 2018 (in thousands) RMS Services and products transferred over time $ 227,872 $ 202,872 Services and products transferred at a point in time 309,217 316,810 DSA Services and products transferred over time 1,618,281 1,316,005 Services and products transferred at a point in time 714 849 Manufacturing Services and products transferred over time 142,896 128,287 Services and products transferred at a point in time 322,246 301,273 Total revenue $ 2,621,226 $ 2,266,096 RMS The RMS business generates revenue through the commercial production and sale of research models and the provision of services related to the maintenance and monitoring of research models and management of clients’ research operations. Revenue from the sale of research models is recognized at a point in time when the customer obtains control of the product, which may be upon shipment or upon delivery based on the shipping terms of a contract. Revenue generated from research models services is recognized over time and is typically based on a right-to-invoice measure of progress (output method) as invoiced amounts correspond directly to the value of the Company’s performance to date. DSA The Discovery and Safety Assessment business provides a full suite of integrated drug discovery services directed at the identification, screening and selection of a lead compound for drug development and offers a full range of safety assessment services including bioanalysis, drug metabolism, pharmacokinetics, toxicology and pathology. Discovery and Safety Assessment services revenue is generally recognized over time using the cost-to-cost or right to invoice measures of progress, primarily representing fixed fee service contracts and per unit service contracts, respectively. Manufacturing The Manufacturing business includes Microbial Solutions, which provides in vitro (non-animal) lot-release testing products, microbial detection products, and species identification services; Biologics Testing Services (Biologics), which performs specialized testing of biologics; and Avian Vaccine Services (Avian), which supplies specific-pathogen-free chicken eggs and chickens. Species identification service revenue is generally recognized at a point in time as identifications are completed by the Company. Biologics service revenue is generally recognized over time using the cost-to-cost measure of progress. Microbial Solutions and Avian product sales are generally recognized at a point in time when the customer obtains control of the product, which may be upon shipment or upon delivery based on the contractual shipping terms of a contract. Transaction Price Allocated to Future Performance Obligations The Company discloses the aggregate amount of transaction price that is allocated to performance obligations that have not yet been satisfied as of December 28, 2019 . Excluded from the disclosure is the value of unsatisfied performance obligations for (i) contracts with an original expected length of one year or less and (ii) contracts for which revenue is recognized at the amount to which the Company has the right to invoice for services performed. The following table includes estimated revenue expected to be recognized in the future related to performance obligations that are unsatisfied (or partially satisfied) as of December 28, 2019 : Revenue Expected to be Recognized in Future Periods Less than 1 Year 1 to 3 Years 4 to 5 Years Beyond 5 Years Total (in thousands) DSA $ 156,125 $ 89,458 $ 5,965 $ 527 $ 252,075 Manufacturing 11,604 11,816 19 13 23,452 Total $ 167,729 $ 101,274 $ 5,984 $ 540 $ 275,527 Contract Balances from Contracts with Customers The timing of revenue recognition, billings and cash collections results in billed receivables (client receivables), contract assets (unbilled revenue), and contract liabilities (current and long-term deferred revenue and customer contract deposits) on the consolidated balance sheets. The Company’s payment terms are generally 30 days in the United States and consistent with prevailing practice in international markets. A contract asset is recorded when a right to consideration in exchange for goods or services transferred to a customer is conditioned other than the passage of time. Client receivables are recorded separately from contract assets since only the passage of time is required before consideration is due. A contract liability is recorded when consideration is received, or such consideration is unconditionally due, from a customer prior to transferring goods or services to the customer under the terms of a contract. Contract liabilities are recognized as revenue after control of the products or services is transferred to the customer and all revenue recognition criteria have been met. The following table provides information about client receivables, contract assets, and contract liabilities from contracts with customers: December 28, 2019 December 29, 2018 (in thousands) Balances from contracts with customers: Client receivables $ 395,740 $ 370,131 Contract assets (unbilled revenue) 121,957 105,216 Contract liabilities (current and long-term deferred revenue) 192,788 179,559 Contract liabilities (customer contract deposits) 33,080 38,245 When the Company does not have the unconditional right to advanced billings, both advanced client payments and unpaid advanced client billings are excluded from deferred revenue, with the advanced billings also being excluded from client receivables. The Company excluded approximately $27 million and $22 million of unpaid advanced client billings from both client receivables and deferred revenue in the accompanying consolidated balance sheets as of December 28, 2019 and December 29, 2018 , respectively. Advanced client payments of approximately $33 million and $38 million have been presented as customer contract deposits within other current liabilities in the accompanying consolidated balance sheets as of December 28, 2019 and December 29, 2018 . Other changes in the contract asset and the contract liability balances during fiscal year 2019 were as follows: (i) Changes due to business combinations: See Note 2. “Business Combinations and Divestiture” for client receivables, contract assets, and contract liabilities that were acquired as part of the Citoxlab acquisition on April 29, 2019. (ii) Cumulative catch-up adjustments to revenue that affect the corresponding contract asset or contract liability, including adjustments arising from a change in the measure of progress, a change in an estimate of the transaction price (including any changes in the assessment of whether an estimate of variable consideration is constrained), or a contract modification: During fiscal year 2019 , an immaterial cumulative catch-up adjustment to revenue was recorded. (iii) A change in the time frame for a right to consideration to become unconditional (that is, for a contract asset to be recorded as a client receivable): Approximately 95% of unbilled revenue as of December 29, 2018 was billed during fiscal year 2019 . (iv) A change in the time frame for a performance obligation to be satisfied (that is, for the recognition of revenue arising from a contract liability): Approximately 85% of contract liabilities as of December 29, 2018 were recognized as revenue during fiscal year 2019 .

SEGMENT AND GEOGRAPHIC INFORMAT

SEGMENT AND GEOGRAPHIC INFORMATION	12 Months Ended
	Dec. 28, 2019
Segment Reporting [Abstract]
SEGMENT AND GEOGRAPHIC INFORMATION	SEGMENT AND GEOGRAPHIC INFORMATION The Company’s three reportable segments are Research Models and Services (RMS), Discovery and Safety Assessment (DSA), and Manufacturing Support (Manufacturing). 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: 2019 2018 2017 (in thousands) RMS Revenue $ 537,089 $ 519,682 $ 493,615 Operating income 133,912 136,468 114,588 Depreciation and amortization 19,197 19,469 19,627 Capital expenditures 26,989 35,172 20,879 DSA Revenue $ 1,618,995 $ 1,316,854 $ 980,022 Operating income 258,903 227,577 182,796 Depreciation and amortization 151,139 112,976 79,355 Capital expenditures 86,843 73,425 36,616 Manufacturing Revenue $ 465,142 $ 429,560 $ 383,964 Operating income 145,420 136,212 123,898 Depreciation and amortization 23,584 22,529 22,893 Capital expenditures 23,617 23,323 15,188 The following tables present reconciliations of segment operating income, depreciation and amortization, and capital expenditures to the respective consolidated amounts: Operating Income Depreciation and Amortization 2019 2018 2017 2019 2018 2017 (in thousands) Total reportable segments $ 538,235 $ 500,257 $ 421,282 $ 193,920 $ 154,974 $ 121,875 Unallocated corporate (187,084 ) (168,874 ) (133,000 ) 4,175 6,805 9,284 Total consolidated $ 351,151 $ 331,383 $ 288,282 $ 198,095 $ 161,779 $ 131,159 Capital Expenditures 2019 2018 2017 (in thousands) Total reportable segments $ 137,449 $ 131,920 $ 72,683 Unallocated corporate 3,065 8,134 9,748 Total consolidated $ 140,514 $ 140,054 $ 82,431 Revenue for each significant product or service offering is as follows : 2019 2018 2017 (in thousands) RMS $ 537,089 $ 519,682 $ 493,615 DSA 1,618,995 1,316,854 980,022 Manufacturing 465,142 429,560 383,964 Total revenue $ 2,621,226 $ 2,266,096 $ 1,857,601 A summary of unallocated corporate expense consists of the following : 2019 2018 2017 (in thousands) Stock-based compensation $ 37,855 $ 32,068 $ 27,114 Compensation, benefits, and other employee-related expenses 73,893 69,191 46,920 External consulting and other service expenses 16,639 18,652 22,224 Information technology 16,080 12,463 11,997 Depreciation 4,175 6,805 9,284 Acquisition and integration 26,877 16,295 3,728 Other general unallocated corporate 11,565 13,400 11,733 Total unallocated corporate expense $ 187,084 $ 168,874 $ 133,000 Other general unallocated corporate expense consists of costs 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 Asia Pacific Other Consolidated (in thousands) 2019 Revenue $ 1,471,097 $ 726,421 $ 271,987 $ 146,218 $ 5,503 $ 2,621,226 Long-lived assets 602,654 253,665 127,495 60,213 101 1,044,128 2018 Revenue $ 1,267,620 $ 643,957 $ 206,382 $ 142,495 $ 5,642 $ 2,266,096 Long-lived assets 597,223 205,185 74,051 56,262 156 932,877 2017 Revenue $ 959,263 $ 569,812 $ 200,343 $ 126,462 $ 1,721 $ 1,857,601 Long-lived assets 446,574 203,911 82,228 49,020 240 781,973 Included in the Asia Pacific category above are operations located in China, Japan, South Korea, Australia, Singapore, and India. Included in the Other category above are operations located in Brazil and Israel. Revenue represents sales originating in entities physically located in the identified geographic area. Long-lived assets consist of property, plant, and equipment, net.

SUPPLEMENTAL BALANCE SHEET INFO

SUPPLEMENTAL BALANCE SHEET INFORMATOIN	12 Months Ended
	Dec. 28, 2019
Supplemental Balance Sheet Information [Abstract]
SUPPLEMENTAL BALANCE SHEET INFORMATION	SUPPLEMENTAL BALANCE SHEET INFORMATION The composition of trade receivables, net is as follows: December 28, 2019 December 29, 2018 (in thousands) Client receivables $ 395,740 $ 370,131 Unbilled revenue 121,957 105,216 Total 517,697 475,347 Less: Allowance for doubtful accounts (3,664 ) (3,099 ) Trade receivables, net $ 514,033 $ 472,248 Net provisions of $3.0 million , $2.1 million , and $0.9 million were recorded to the allowance for doubtful accounts in fiscal years 2019 , 2018 , and 2017 , respectively. The composition of inventories is as follows: December 28, 2019 December 29, 2018 (in thousands) Raw materials and supplies $ 24,613 $ 22,378 Work in process 35,852 21,732 Finished products 100,195 83,782 Inventories $ 160,660 $ 127,892 The composition of other current assets is as follows: December 28, 2019 December 29, 2018 (in thousands) Prepaid income tax $ 54,358 $ 47,157 Short-term investments 941 885 Restricted cash 431 465 Other 300 300 Other current assets $ 56,030 $ 48,807 The composition of property, plant and equipment, net is as follows: December 28, 2019 December 29, 2018 (in thousands) Land $ 63,077 $ 52,266 Buildings (1) 1,006,357 938,184 Machinery and equipment (1) 585,965 501,894 Leasehold improvements 84,630 59,854 Furniture and fixtures 28,304 26,700 Computer hardware and software (1) 179,865 166,398 Vehicles (1) 5,561 5,167 Construction in progress 67,939 56,549 Total 2,021,698 1,807,012 Less: Accumulated depreciation (977,570 ) (874,135 ) Property, plant and equipment, net $ 1,044,128 $ 932,877 (1) These balances include assets under finance leases. See Note 16, “Leases.” Depreciation expense in fiscal years 2019 , 2018 and 2017 was $108.6 million , $96.9 million and $89.8 million , respectively. The composition of other assets is as follows: December 28, 2019 December 29, 2018 (in thousands) Venture capital investments $ 108,983 $ 87,545 Other investments 13,996 1,046 Life insurance policies 38,207 32,340 Restricted cash 1,601 1,411 Other 49,828 21,417 Other assets $ 212,615 $ 143,759 The composition of other current liabilities is as follows: December 28, 2019 December 29, 2018 (in thousands) Current portion of operating lease right-of-use liabilities $ 20,357 $ — Accrued income taxes 26,066 24,120 Customer contract deposits 33,080 38,245 Other 11,095 8,915 Other current liabilities $ 90,598 $ 71,280 The composition of other long-term liabilities is as follows: December 28, 2019 December 29, 2018 (in thousands) U.S. Transition Tax $ 52,066 $ 52,064 Long-term pension liability 43,054 24,671 Accrued executive supplemental life insurance retirement plan and deferred compensation plan 37,779 36,086 Long-term deferred revenue 20,983 34,420 Other 29,051 31,880 Other long-term liabilities $ 182,933 $ 179,121

VENTURE CAPITAL INVESTMENTS AND

VENTURE CAPITAL INVESTMENTS AND OTHER INVESTMENTS	12 Months Ended
	Dec. 28, 2019
Marketable Securities and Equity-Method Affiliates [Abstract]
VENTURE CAPITAL INVESTMENTS AND OTHER INVESTMENTS	VENTURE CAPITAL AND OTHER INVESTMENTS Venture capital investments were $109.0 million and $87.5 million as of December 28, 2019 and December 29, 2018 , respectively. The Company’s total commitment to the venture capital funds as of December 28, 2019 was $128.4 million , of which the Company funded $80.3 million through that date. During fiscal years 2019 , 2018 , and 2017 , the Company received dividends totaling $11.4 million , $18.2 million , and $10.1 million , respectively. During fiscal years 2019 , 2018 , and 2017 , the Company recognized gains related to the venture capital investments of $20.7 million , $15.9 million and $22.9 million , respectively. As of December 28, 2019 and December 29, 2018 , the Company’s consolidated retained earnings included $20.6 million and $14.1 million , respectively, of the undistributed earnings related to these investments. Other investments were $14.0 million and $1.0 million as of December 28, 2019 and December 29, 2018 , respectively. The Company recognized an insignificant amount of gains and losses related to these investments for fiscal years 2019 and 2018 . Gains and losses from venture capital and other investments are recorded in Other income, net in the accompanying consolidated statements of income.

FAIR VALUE

FAIR VALUE	12 Months Ended
	Dec. 28, 2019
Fair Value Disclosures [Abstract]
FAIR VALUE	FAIR VALUE Assets and liabilities measured at fair value on a recurring basis are summarized below: December 28, 2019 Level 1 Level 2 Level 3 Total (in thousands) Cash equivalents $ — $ 55,278 $ — $ 55,278 Other assets: Life insurance policies — 30,454 — 30,454 Total assets measured at fair value $ — $ 85,732 $ — $ 85,732 Other current liabilities measured at fair value: Contingent consideration $ — $ — $ 712 $ 712 Foreign currency forward contract — 876 — 876 Total liabilities measured at fair value $ — $ 876 $ 712 $ 1,588 December 29, 2018 Level 1 Level 2 Level 3 Total (in thousands) Cash equivalents $ — $ 45,982 $ — $ 45,982 Other assets: Life insurance policies — 24,541 — 24,541 Total assets measured at fair value $ — $ 70,523 $ — $ 70,523 Other current liabilities: Contingent consideration $ — $ — $ 3,033 $ 3,033 Foreign currency forward contract — 1,319 — 1,319 Total liabilities measured at fair value $ — $ 1,319 $ 3,033 $ 4,352 During fiscal years 2019 and 2018 , there were no transfers between fair value levels. Contingent Consideration The following table provides a rollforward of the contingent consideration related to previous business acquisitions. See Note 2, “Business Combinations and Divestiture”. Fiscal Year 2019 2018 (in thousands) Beginning balance $ 3,033 $ 298 Additions 2,869 3,315 Payments (5,252 ) — Total gains or losses (realized/unrealized): Foreign currency translation 62 (298 ) Reversal of previously recorded contingent liability and change in fair value — (282 ) Ending balance $ 712 $ 3,033 The 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. Increases or decreases in any of the probabilities of success would result in a higher or lower fair value measurement, respectively. Increases or decreases in the discount rate would result in a 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 the 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 within the fair value hierarchy. The book value of the Company’s 2026 and 2028 Senior Notes is a fixed rate obligation carried at amortized cost. Fair value is based on quoted market prices as well as borrowing rates available to the Company. As the fair value is based on significant other observable outputs, it is deemed to be Level 2 within the fair value hierarchy. The book value and fair value of the Company’s 2026 and 2028 Senior Notes is summarized below: December 28, 2019 December 29, 2018 Book Value Fair Value Book Value Fair Value 2026 Senior Notes $ 500,000 $ 537,500 $ 500,000 $ 495,000 2028 Senior Notes 500,000 510,000 — —

GOODWILL AND INTANGIBLE ASSETS

GOODWILL AND INTANGIBLE ASSETS	12 Months Ended
	Dec. 28, 2019
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 30, 2017 Acquisitions Foreign Exchange December 29, 2018 Acquisitions Foreign Exchange December 28, 2019 (in thousands) RMS $ 58,122 $ — $ (1,154 ) $ 56,968 $ — $ (382 ) $ 56,586 DSA 1,610,176 460,223 (13,929 ) 2,056,470 293,380 373 2,350,223 Manufacturing 141,608 2,551 (5,464 ) 138,695 — 61 138,756 Gross carrying amount 1,809,906 462,774 (20,547 ) 2,252,133 293,380 52 2,545,565 Accumulated impairment loss - DSA (1,005,000 ) — — (1,005,000 ) — — (1,005,000 ) Goodwill $ 804,906 $ 1,247,133 $ 1,540,565 Based on the Company’s step one goodwill impairment test, which was performed in the fourth quarter for each of the fiscal years 2019 , 2018 and 2017 , the fair value of each reporting unit exceeded the reporting unit’s book value and, therefore, goodwill was not impaired. The increase in goodwill during fiscal year 2019 related primarily to the acquisition of Citoxlab in the DSA reportable segment. The increase in goodwill during fiscal year 2018 related primarily to the acquisitions of MPI Research and KWS BioTest in the DSA reportable segment, an immaterial acquisition of an Australian business in the Manufacturing reportable segment, and the impact of foreign exchange. Intangible Assets, Net The following table displays intangible assets, net by major class: December 28, 2019 December 29, 2018 Gross Accumulated Net Gross Accumulated Net (in thousands) Backlog $ 28,865 $ (26,895 ) $ 1,970 $ 20,900 $ (18,691 ) $ 2,209 Technology 122,106 (57,737 ) 64,369 101,506 (41,870 ) 59,636 Trademarks and trade names 8,430 (4,901 ) 3,529 8,331 (4,640 ) 3,691 Other 18,279 (12,307 ) 5,972 17,448 (10,041 ) 7,407 Other intangible assets 177,680 (101,840 ) 75,840 148,185 (75,242 ) 72,943 Client relationships 934,668 (321,095 ) 613,573 791,725 (253,780 ) 537,945 Intangible assets $ 1,112,348 $ (422,935 ) $ 689,413 $ 939,910 $ (329,022 ) $ 610,888 The increase in intangible assets, net during the fiscal year 2019 related primarily to the acquisition of Citoxlab. The increase in intangible assets, net during the fiscal year 2018 related primarily to the acquisitions of MPI Research and KWS BioTest. Amortization expense of definite-lived intangible assets, including client relationships, for fiscal years 2019 , 2018 and 2017 was $89.5 million , $64.8 million and $41.4 million , respectively. As of December 28, 2019 , 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) 2020 $ 97,024 2021 87,540 2022 76,204 2023 67,807 2024 60,918

LONG-TERM DEBT AND FINANCE LEAS

LONG-TERM DEBT AND FINANCE LEASE OBLIGATIONS	12 Months Ended
	Dec. 28, 2019
Debt Disclosure [Abstract]
LONG-TERM DEBT AND CAPITAL LEASE OBLIGATIONS	LONG-TERM DEBT AND FINANCE LEASE OBLIGATIONS Long-term debt, net and finance leases consists of the following: December 28, 2019 December 29, 2018 (in thousands) Term loans $ 193,750 $ 731,250 Revolving facility 676,134 397,452 2026 Senior Notes 500,000 500,000 2028 Senior Notes 500,000 — Other debt 5,781 26,286 Finance leases (Note 16) 30,527 29,240 Total debt and finance leases 1,906,192 1,684,228 Less: Current portion of long-term debt 35,548 28,228 Current portion of finance leases (Note 16) 2,997 3,188 Current portion of long-term debt and finance leases 38,545 31,416 Long-term debt and finance leases 1,867,647 1,652,812 Debt discount and debt issuance costs (17,981 ) (16,214 ) Long-term debt, net and finance leases $ 1,849,666 $ 1,636,598 The acquisition of HemaCare on January 3, 2020 for approximately $380 million was funded through a combination of cash on hand and proceeds from the Company’s Credit Facility under the multi-currency revolving facility. The increased borrowings occurred subsequent to December 28, 2019 and are not reflected in the table above. As of December 28, 2019 and December 29, 2018 , the weighted average interest rate on the Company’s debt was 3.46% and 4.24% , respectively. Term Loans and Revolving Facility On March 26, 2018, the Company amended and restated its $1.65 billion credit facility creating a $2.3 billion credit facility (Credit Facility). The amendment extended the maturity date and provided for a $750 million term loan and a $1.55 billion multi-currency revolving facility. The amendment was accounted for as a debt modification. In connection with the transaction, the Company capitalized $6.2 million within Long-term debt, net and finance leases in the accompanying consolidated balance sheets and expensed $1.0 million of debt issuance costs recorded within Interest expense in the accompanying consolidated statements of income for the year ended 2018. The term loan facility matures in 19 quarterly installments with the last installment due March 26, 2023. The revolving facility matures on March 26, 2023, and requires no scheduled payment before that date. On September 25, 2019, the Company amended and restated the Credit Facility for certain administrative matters. On October 23, 2019, the Company prepaid $500.0 million of the term loan with proceeds from a $500.0 million unregistered private offering (see 2028 Senior Notes Offering below) which was treated as a debt modification. Additionally, on November 4, 2019, the Company amended and restated the Credit Facility to increase the multi-currency revolving facility by $500.0 million , from $1.55 billion to $2.05 billion . In connection with these transactions, the Company capitalized $0.5 million within Long-term debt, net and finance leases in the accompanying consolidated balance sheets and expensed $1.6 million of debt issuance costs recorded within Interest expense in the accompanying consolidated statements of income for the year ended 2019. Under specified circumstances, the Company has the ability to increase the term loan and/or revolving facility by up to $1.0 billion in the aggregate. The interest rates applicable to the term loan and revolving facility under the Credit Facility are, at the Company’s option, equal to either the base rate (which is the higher of (1) the prime rate, (2) the federal funds rate plus 0.50% , or (3) the one-month adjusted LIBOR rate plus 1.0% ) or the adjusted LIBOR rate, plus an interest rate margin based upon the Company’s leverage ratio. The 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 3.50 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 4.00 to 1.0. As of December 28, 2019 , the Company was compliant with all covenants. The obligations of the Company under the Credit Facility are collateralized by substantially all of the assets of the Company. During fiscal years 2019 and 2018 , the Company had multiple U.S. dollar denominated loans borrowed by a non-U.S. Euro functional currency entity under the Company’s Credit Facility, which ranged from $300 million to $400 million each. This resulted in foreign currency losses recognized in Other income, net of $9.6 million and less than $0.1 million during fiscal years 2019 and 2018 , respectively, related to the remeasurement of the underlying debt. The Company entered into foreign exchange forward contracts to limit its foreign currency exposures related to these borrowings and recognized gains of $18.7 million and $1.5 million during fiscal years 2019 and 2018 , respectively, within Interest expense. As of December 28, 2019 , the Company did not have any outstanding borrowings in a currency different than its respective functional currency. See Note 14, “Foreign Currency Contracts”, for further discussion. Base Indenture for Senior Notes Offerings On April 3, 2018, the Company entered into an indenture (Base Indenture) with MUFG Union Bank, N.A., (Trustee). The purpose of the Indenture was to allow the Company the ability to issue senior notes. The Company has entered into two supplemental indentures in connection with two unregistered offerings, which are described below. The Indenture contains certain covenants including, but not limited to, limitations and restrictions on the ability of the Company and its U.S. subsidiaries to (i) create certain liens, (ii) enter into any Sale and Leaseback Transaction (as defined in the Indenture) with respect to any property, and (iii) merge, consolidate, sell or otherwise dispose of all or substantially all of their assets. These covenants are subject to a number of conditions, qualifications, exceptions and limitations. Any event of default, as defined, could result in the acceleration of the repayment of the obligations. 2026 Senior Notes Offering On April 3, 2018, the Company entered into the first supplemental indenture (First Supplemental Indenture) with the Trustee in connection with an offering of $500 million in aggregate principal amount of the Company’s 5.5% Senior Notes (2026 Senior Notes), due in 2026, in an unregistered offering. Under the terms of the First Supplemental Indenture, interest on the Senior Notes is payable semi-annually on April 1 and October 1, beginning on October 1, 2018. The 2026 Senior Notes are guaranteed fully and unconditionally, jointly and severally on a senior unsecured basis by the Company and certain of its U.S. subsidiaries. In connection with the transaction, the Company incurred $7.4 million of debt issuance costs, which the Company capitalized upon issuance on April 3, 2018 and recorded within Long-term debt, net and finance leases in the accompanying consolidated balance sheets. The Company may redeem all or part of the 2026 Senior Notes at any time prior to April 1, 2021, at its option, at a redemption price equal to 100.0% of the principal amount of such Senior Notes plus the Applicable Premium (as defined in the First Supplemental Indenture). The Company may also redeem up to 40.0% of the Senior Notes with the proceeds of certain equity offerings completed before April 1, 2021, at a redemption price equal to 105.5% of the principal amount of such 2026 Senior Notes. On or after April 1, 2021, the Company may on any one or more occasions redeem all or a part of the 2026 Senior Notes, at the redemption prices specified in the Indenture based on the applicable date of redemption. Upon the occurrence of a Change of Control Triggering Event (as defined in the Indenture), the Company will be required to offer to repurchase the 2026 Senior Notes at a purchase price equal to 101.0% of the aggregate principal amount of such 2026 Senior Notes. Any redemption of the 2026 Senior Notes would also require settlement of accrued and unpaid interest, if any, up to but excluding the redemption date. Net proceeds from the 2026 Senior Notes of $493.8 million were used to partially repay the outstanding revolving credit facility on April 3, 2018 as well as fund the acquisition of MPI Research. 2028 Senior Notes Offering On October 23, 2019, the Company entered into a second supplemental indenture (Second Supplemental Indenture) with the Trustee in connection with the offering of $500 million in aggregate principal amount of the Company’s 4.25% Senior Notes (2028 Senior Notes), due in 2028, in an unregistered offering. Under the terms of the Second Supplemental Indenture, interest on the 2028 Senior Notes is payable semi-annually on May 1 and November 1, beginning on May 1, 2020. The 2028 Senior Notes are guaranteed fully and unconditionally, jointly and severally on a senior unsecured basis by the Company and certain of its U.S. subsidiaries. In connection with the transaction, the Company incurred approximately $6 million of debt issuance costs, which were capitalized upon the 2028 Senior Notes issuance on October 23, 2019, and was recorded within Long-term debt, net and finance leases in the accompanying consolidated balance sheets. The Company may redeem all or part of the 2028 Senior Notes at any time prior to May 1, 2023, at its option, at a redemption price equal to 100% of the principal amount of such 2028 Senior Notes plus the Applicable Premium (as defined in the Indenture). The Company may also redeem up to 40% of the 2028 Senior Notes with the proceeds of certain equity offerings completed before May 1, 2023, at a redemption price equal to 104.25% of the principal amount of such 2028 Senior Notes. On or after May 1, 2023, the Company may on any one or more occasions redeem all or a part of the 2028 Senior Notes, at the redemption prices specified in the Indenture based on the applicable date of redemption. Upon the occurrence of a Change of Control Triggering Event (as defined in the Indenture), the Company will be required to offer to repurchase the Senior Notes at a purchase price equal to 101% of the aggregate principal amount of such Senior Notes. Any redemption of the Senior Notes would also require settlement of accrued and unpaid interest, if any, up to but excluding the redemption date. Net proceeds from the 2028 Senior Notes of approximately $494 million and available cash were used to prepay a portion of the term loan on October 23, 2019. Commitment Letter On February 12, 2018, the Company secured an $830 million commitment under a 364-day senior unsecured bridge loan facility (Bridge Facility) for the purpose of financing the acquisition of MPI Research. The Bridge Facility was terminated as of April 3, 2018 upon the successful acquisition of MPI Research. Debt issuance costs of $1.8 million , which were capitalized upon the execution of the Bridge Facility, were expensed upon termination of the agreement on April 3, 2018. In addition, the Company incurred and expensed $2.0 million of fees pertaining to a temporary backstop facility related to the negotiation of the Credit Facility during the three months ended March 31, 2018. These costs were included within Interest expense in the accompanying consolidated statements of income. Principal Maturities Principal maturities of existing debt for the periods set forth in the table below, are as follows: Principal (in thousands) 2020 $ 35,536 2021 61,151 2022 93,966 2023 682,602 2024 468 Thereafter 1,001,942 Total $ 1,875,665 Letters of Credit As of December 28, 2019 and December 29, 2018 , the Company had $7.5 million and $6.5 million , respectively, in outstanding letters of credit.

EQUITY AND NONCONTROLLING INTER

EQUITY AND NONCONTROLLING INTERESTS	12 Months Ended
	Dec. 28, 2019
Equity [Abstract]
EQUITY AND NONCONTROLLING INTERESTS	EQUITY AND NONCONTROLLING INTERESTS Earnings Per Share The following table reconciles the numerator and denominator in the computations of basic and diluted earnings per share: Fiscal Year 2019 2018 2017 (in thousands) Numerator: Income from continuing operations, net of income taxes $ 254,061 $ 227,218 $ 125,586 Income (loss) from discontinued operations, net of income taxes — 1,506 (137 ) Less: Net income attributable to noncontrolling interests 2,042 2,351 2,094 Net income attributable to common shareholders $ 252,019 $ 226,373 $ 123,355 Denominator: Weighted-average shares outstanding— Basic 48,730 47,947 47,481 Effect of dilutive securities: Stock options, restricted stock, restricted stock units and performance share units 963 1,071 1,083 Weighted-average shares outstanding—Diluted 49,693 49,018 48,564 Options to purchase 0.4 million shares, 0.5 million shares, and 0.6 million shares for fiscal years 2019 , 2018 and 2017 , respectively, as well as a non-significant number of restricted shares, RSUs, and performance share units (PSUs), were not included in computing diluted earnings per share because their inclusion would have been anti-dilutive. Basic weighted-average shares outstanding for fiscal years 2019 , 2018 and 2017 excluded the impact of 1.0 million shares, 1.0 million shares and 1.1 million shares, respectively, of non-vested restricted stock, RSUs 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 , $150.0 million in 2014, and $150.0 million in 2017, for an aggregate authorization of $1.3 billion . Under its authorized stock repurchase program, the Company did no t repurchase any shares in fiscal years 2019 and 2018 . The Company repurchased 1.0 million shares totaling $90.6 million in fiscal year 2017 . As of December 28, 2019 , the Company had $129.1 million remaining on the authorized stock repurchase program. The Company’s stock-based compensation plans permit the netting of common stock upon vesting of restricted stock, RSUs, and PSUs in order to satisfy individual statutory tax withholding requirements. The Company acquired 0.1 million shares for $18.1 million , 0.1 million shares for $13.8 million , and 0.2 million shares for $16.3 million in fiscal years 2019 , 2018 and 2017 , respectively, from such netting. In fiscal years 2019 and 2018 , the Company’s Board of Directors approved the cancellation and return to the Company’s authorized and unissued capital stock of 0.1 million treasury shares totaling $18.1 million and 40.2 million treasury shares totaling $1.7 billion , respectively, reducing treasury stock on the Company’s consolidated balance sheet. The Company allocated the excess of the repurchase price over the par value of shares acquired to reduce both retained earnings and additional paid-in capital for $13.8 million and $4.3 million , respectively, in fiscal 2019 and $0.5 billion and $1.2 billion , respectively, in fiscal year 2018 . 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 Adjustment and Other Pension and Other Post-Retirement Benefit Plans Total (in thousands) December 30, 2017 $ (77,545 ) $ (67,186 ) $ (144,731 ) Other comprehensive loss before reclassifications (1) (27,352 ) (1,659 ) (29,011 ) Amounts reclassified from accumulated other comprehensive income (loss) — 2,477 2,477 Net current period other comprehensive (loss) income (27,352 ) 818 (26,534 ) Amount reclassified from accumulated other comprehensive loss due to the adoption of ASU 2018-02 — 3,330 3,330 Income tax (benefit) expense (2,698 ) 806 (1,892 ) December 29, 2018 (102,199 ) (70,504 ) (172,703 ) Other comprehensive income (loss) before reclassifications (1) 14,444 (25,165 ) (10,721 ) Amounts reclassified from accumulated other comprehensive income (loss) — 1,772 1,772 Net current period other comprehensive income (loss) 14,444 (23,393 ) (8,949 ) Income tax (benefit) (177 ) (3,456 ) (3,633 ) December 28, 2019 $ (87,578 ) $ (90,441 ) $ (178,019 ) (1) The impact of the foreign currency translation adjustment to other comprehensive income (loss) before reclassifications was primarily due to the effect of changes in foreign currency exchange rates of the Euro, British Pound, and Canadian Dollar and to a lesser extent due to the impact of changes in the Chinese Yuan Renminbi and Japanese Yen. Nonredeemable Noncontrolling Interest The Company has an investment in an entity whose financial results are consolidated in the Company’s financial statements, as it has the ability to exercise control over this entity. The interest of the noncontrolling party in this entity has been recorded as noncontrolling interest within Equity in the accompanying consolidated balance sheets. The activity within the nonredeemable noncontrolling interest during fiscal years 2019 , 2018 , and 2017 was not significant. Redeemable Noncontrolling Interests In January 2013, the Company acquired a 75% ownership interest in 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. Concurrent with the acquisition, the Company entered into an agreement with the noncontrolling interest holders that provided the Company with the right to purchase, and the noncontrolling interest holders with the right to sell, the remaining 25% of the entity for cash at its fair value beginning in January 2016. As the noncontrolling interest holders have the ability to require the Company to purchase the remaining interest, the noncontrolling interest is classified in the mezzanine section of the consolidated balance sheets, which is presented above the equity section and below liabilities. The agreement does not limit the amount that the Company could be required to pay to purchase the remaining equity interest. During fiscal years 2016 through the 2019, the following transactions and amendments impacted the Vital River redeemable noncontrolling interest as follows: • On July 7, 2016, the Company purchased an additional 12% equity interest in Vital River for $10.8 million , resulting in total ownership of 87% . Concurrent with the transaction, the original agreement was amended providing the Company with the right to purchase, and the noncontrolling interest holders with the right to sell, the remaining 13% equity interest at a contractually defined redemption value, subject to a redemption floor, which represents a derivative embedded within the equity instrument. These rights are exercisable beginning in 2019 and are accelerated in certain events. Subsequent to the amendment during fiscal years 2016 through 2019, the redeemable noncontrolling interest was measured at the greater of the amount that would be paid if settlement occurred as of the balance sheet date based on the contractually defined redemption value ( $18.5 million as of December 29, 2018) and its carrying amount adjusted for net income (loss) attributable to the noncontrolling interest. • On June 13, 2019, the Company purchased an additional 5% equity interest in Vital River for $7.9 million , resulting in total ownership of 92% . The Company recorded a $0.8 million gain in equity equal to the excess fair value of the 5% equity interest over the purchase price. Concurrent with the transaction, the pre-existing agreement was further amended to provide the Company with the right to purchase, and the noncontrolling interest holders with the right to sell, the remaining 8% equity interest (redeemable noncontrolling interest) at a contractually defined redemption value, subject to a redemption floor, which represents a derivative embedded within the equity instrument. These rights are exercisable beginning in 2022 and are accelerated in certain events. The Company recorded a charge of $2.2 million in Selling, general and administrative expenses within the consolidated statements of income, equal to the excess fair value of the hybrid instrument (equity interest with embedded derivative) over the fair value of the 8% equity interest. The redeemable noncontrolling interest is measured at the greater of the amount that would be paid if settlement occurred as of the balance sheet date based on the contractually defined redemption value ( $15.5 million as of December 28, 2019 ) and the carrying amount adjusted for net income (loss) attributable to the noncontrolling interest. As the noncontrolling interest holders have the ability to require the Company to purchase the remaining 8% interest, the noncontrolling interest is classified in the mezzanine section of the consolidated balance sheets, which is presented above the equity section and below liabilities. The agreement does not limit the amount that the Company could be required to pay to purchase the remaining 8% equity interest. As part of the Citoxlab acquisition on April 29, 2019 , the Company acquired a less than wholly owned subsidiary that is fully consolidated under the voting interest model. The Company acquired an approximate 90% equity interest, which includes an approximate 10% redeemable noncontrolling interest. The noncontrolling interest holders have the ability to require the Company to purchase the remaining approximate 10% interest at certain dates in the future between 2021 through 2023. The noncontrolling interest is classified in the mezzanine section of the consolidated balance sheets and is approximately $4 million as of December 28, 2019 . On August 28, 2019 , the Company acquired an 80% equity interest in a supplier, which included a 20% redeemable noncontrolling interest. The contract provides the Company the right to purchase, and the noncontrolling interest holders with the right to sell, the remaining 20% equity interest at its appraised value. These rights are exercisable beginning in 2022. The redeemable noncontrolling interest is measured at the greater of the amount that would be paid if settlement occurred as of the balance sheet date based on the appraised value and the carrying amount adjusted for net income (loss) attributable to the noncontrolling interest or a pre-determined floor value. As the noncontrolling interest holders have the ability to require the Company to purchase the remaining 20% interest, the noncontrolling interest is classified in the mezzanine section of the consolidated balance sheets, which is presented above the equity section and below liabilities. The agreement does not limit the amount that the Company could be required to pay to purchase the remaining 20% equity interest. The following table provides a rollforward of the activity related to the Company’s redeemable noncontrolling interests: Fiscal Year 2019 2018 (in thousands) Beginning balance $ 18,525 $ 16,609 Adjustment to Vital River redemption value 1,451 2,069 Purchase of Vital River 5% equity interest (8,745 ) — Change in fair value of Vital River 8% equity interest, included in additional paid-in capital 2,708 — Modification of Vital River 8% purchase option 2,196 — Acquisition of an approximate 10% non-controlling interest through acquiring Citoxlab 4,035 — Acquisition of a 20% non-controlling interest through acquiring a supplier 8,740 — Net (loss) income attributable to noncontrolling interests (42 ) 800 Foreign currency translation (221 ) (953 ) Ending balance $ 28,647 $ 18,525

INCOME TAXES

INCOME TAXES	12 Months Ended
	Dec. 28, 2019
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 2019 2018 2017 (in thousands) Income from continuing operations before income taxes: U.S. $ 108,326 $ 95,062 $ 123,896 Non-U.S. 195,758 186,619 173,059 $ 304,084 $ 281,681 $ 296,955 Income tax provision (benefit): Current: Federal $ 18,101 $ 17,390 $ 93,871 Foreign 43,489 38,557 37,150 State 9,915 8,837 12,361 Total current 71,505 64,784 143,382 Deferred: Federal (3,226 ) (7,145 ) 9,416 Foreign (17,111 ) (4,104 ) 14,953 State (1,145 ) 928 3,618 Total deferred (21,482 ) (10,321 ) 27,987 $ 50,023 $ 54,463 $ 171,369 Included in the fiscal year 2019 tax expense of $50.0 million is a $20.6 million tax benefit for the recognition of $315.5 million of historical foreign net operating loss deferred tax assets, partially offset by a $294.9 million valuation allowance. Prior to 2019 , these deferred tax assets were not recognized as the Company believed the ability to utilize the net operating losses was remote. As a result of both U.S. Tax Reform and European tax legislation, the Company made changes in 2019 to its financing structure, resulting in the ability to utilize a portion of the net operating losses previously considered remote in nature. The Company’s accounting for the elements of U.S. Tax Reform is complete based on all published tax law and corresponding guidance. However, proposed and final clarifying guidance is anticipated for various aspects of U.S. Tax Reform which are relevant to the Company. The effects of any additional guidance will be recorded in the period such guidance is issued. Reconciliations of the statutory U.S. federal income tax rate to effective tax rates are as follows: Fiscal Year 2019 2018 2017 U.S. statutory income tax rate 21.0 % 21.0 % 35.0 % Foreign tax rate differences 2.7 0.5 (6.8 ) State income taxes, net of federal tax benefit 2.6 2.4 2.0 Non-deductible compensation 1.7 1.0 1.3 Research tax credits and enhanced deductions (4.4 ) (2.9 ) (2.4 ) Stock-based compensation (2.2 ) (2.1 ) (3.2 ) Enacted tax rate changes (0.7 ) (0.1 ) (4.2 ) Transition Tax — (0.3 ) 24.8 Impact of tax uncertainties (2.6 ) (1.1 ) (0.4 ) Tax on unremitted earnings 1.7 1.2 7.3 Impact of acquisitions and restructuring 2.7 0.3 3.8 Net operating loss deferred tax asset recognition, net of valuation allowance (NOL DTA) (6.8 ) — — Other 0.8 (0.6 ) 0.5 Effective income tax rate 16.5 % 19.3 % 57.7 % The components of deferred tax assets and liabilities are as follows: December 28, 2019 December 29, 2018 (in thousands) Deferred tax assets: Compensation $ 40,582 $ 36,724 Accruals and reserves 13,687 13,183 Net operating loss and credit carryforwards 367,269 35,679 Operating lease liability 33,785 — Other 7,181 5,060 Valuation allowance (309,962 ) (9,788 ) Total deferred tax assets 152,542 80,858 Deferred tax liabilities: Goodwill and other intangibles (174,847 ) (154,743 ) Depreciation related (29,317 ) (19,373 ) Venture capital investments (12,806 ) (10,557 ) Tax on unremitted earnings (17,282 ) (14,140 ) Right-of-use assets (34,953 ) — Other (5,961 ) (2,296 ) Total deferred tax liabilities (275,166 ) (201,109 ) Net deferred taxes $ (122,624 ) $ (120,251 ) The valuation allowance increased by $300.2 million from $9.8 million as of December 29, 2018 to $310.0 million as of December 28, 2019 . The increase is primarily related to the recognition of $315.5 million of net operating loss deferred tax assets due to changes in the Company’s financing structure, $294.9 million of which the Company does not believe is more likely than not to be utilized. As of December 28, 2019 , the Company had foreign net operating loss carryforwards of $337.3 million , as compared to $35.7 million as of December 29, 2018 . Of this amount, $23.3 million are definite-lived and begin to expire in 2020 , and the remainder of $314.0 million can be carried forward indefinitely. The Company has tax credit carryforwards of $30.1 million , which will begin to expire after 2035 and beyond. Additionally, the Company records a benefit to operating income for research and development and other credits in Quebec, France, the Netherlands, and the U.K. related to its DSA facilities. The Company has 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, certain capital losses, and fixed assets in the U.K. A reconciliation of the Company’s beginning and ending unrecognized income tax benefits is as follows: Fiscal Year 2019 2018 2017 (in thousands) Beginning balance $ 18,827 $ 24,710 $ 24,186 Additions to tax positions for current year 3,691 2,477 1,791 Additions to tax positions for prior years 5,234 — 1,428 Reductions to tax positions for prior years (1,033 ) (4,543 ) — Settlements (274 ) (3,380 ) (1,754 ) Expiration of statute of limitations (6,780 ) (437 ) (941 ) Ending balance $ 19,665 $ 18,827 $ 24,710 The $0.8 million increase in unrecognized income tax benefits during fiscal year 2019 as compared to the corresponding period in 2018 is primarily attributable to increases due to business combinations and an additional year of Canadian SR&ED credit, partially offset by expiration of statutes of limitations. The amount of unrecognized income tax benefits that, if recognized, would favorably impact the effective tax rate was $17.0 million as of December 28, 2019 and $17.6 million as of December 29, 2018 . The $0.6 million decrease is primarily attributable to expiration of statutes of limitations, partially offset by increases due to business combinations and an additional year of Federal Canadian SR&ED credit. It is reasonably possible as of December 28, 2019 that the liability for unrecognized tax benefits for the uncertain tax position will decrease by $ 4.0 million over the next twelve month period, primarily as a result of lapsing statutes of limitations. 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 28, 2019 and December 29, 2018 was $2.3 million and $2.7 million , respectively. There were no accrued penalties related to unrecognized income tax benefits as of December 28, 2019 or as of December 29, 2018 . 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., China, France, Germany, and Canada. With few exceptions, the Company is no longer subject to U.S. and international income tax examinations for years before 2016. The Company and certain of its subsidiaries have ongoing tax controversies in the U.S., France and Canada. The Company does not anticipate resolution of these audits will have a material impact on its financial statements.

EMPLOYEE BENEFIT PLANS

EMPLOYEE BENEFIT PLANS	12 Months Ended
	Dec. 28, 2019
Retirement Benefits [Abstract]
EMPLOYEE BENEFIT PLANS	EMPLOYEE BENEFIT PLANS Pension Plans The Charles River Laboratories, Inc. Pension Plan (U.S. Pension Plan) is a qualified, non-contributory defined benefit plan covering certain U.S. employees. Effective 2002, the U.S. Pension Plan was amended to exclude new participants from joining and in 2008 the accrual of benefits was frozen. On January 31, 2019, the Company commenced the process to terminate the U.S. Pension Plan and expects to complete the termination process during fiscal year 2020 . As part of the planned termination, the Company re-balanced assets to a target asset allocation (primarily fixed income investments) to better match our assets to the characteristics of the liabilities. At December 28, 2019 , the U.S Pension Plan has a benefit obligation of $94.4 million and plan assets of $91.2 million . The benefit obligation has been valued at the amount expected to be required to settle the obligations. Assumptions utilized considered the portion of obligations expected to be settled through participant acceptance of lump sum payments or annuities and the cost to purchase annuities, which are subject to change upon actual plan settlement. Increasing the U.S Pension Plan’s obligations to reflect the expected settlement value resulted in an actuarial loss of approximately $6 million , which was recorded to Other comprehensive income as part of the annual revaluation for fiscal year 2019. In the event that approvals are received and we proceed with effecting termination of this plan, settlement of the obligation is expected to occur in the second half of 2020. Upon settlement of the benefit obligation, the Company will reclassify the related pension losses, currently recorded within Accumulated other comprehensive loss on the consolidated balance sheet, to Other expense, net in the consolidated statements of income. As of December 28, 2019, the Company had unrecognized losses related to the U.S. Pension Plan of approximately $14 million . The Charles River Pension Plan (U.K. 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 U.K. Pension Plan was amended such that the members of the defined benefit section of the plan ceased to accrue additional benefits; however, their benefits 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 Canada, France, Germany, Japan, Italy, and the Netherlands. The net periodic benefit cost (income) associated with these plans for fiscal years 2019 , 2018 and 2017 totaled $1.5 million , $(1.5) million and $1.6 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 U.S. 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. In fiscal year 2019, one executive officer, who converted their ESLIRP benefit into the DCP, announced their intention to retire in May 2020 and therefore the DCP liability reflects the expected departure. The net periodic benefit cost associated with these plans for fiscal years 2019 , 2018 and 2017 totaled $2.5 million , $ 2.9 million and $2.3 million , respectively. The Company has invested in several corporate-owned key-person life insurance policies 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 28, 2019 and December 29, 2018 , the cash surrender value of these life insurance policies were $38.2 million and $32.3 million , respectively. The following table provides a reconciliation of benefit obligations and plan assets of the Company’s pension, DCP and ESLIRP plans: December 28, 2019 December 29, 2018 (in thousands) Change in projected benefit obligations: Benefit obligation at beginning of year $ 362,805 $ 392,964 Service cost 2,833 2,612 Interest cost 11,583 10,850 Other 850 1,499 Benefit payments (11,062 ) (8,886 ) Settlements (74 ) — Special/Contractual Termination Benefits 166 — Plan amendments — 104 Transfer in from acquisition 6,818 — Actuarial loss (gain) 66,432 (21,168 ) Administrative expenses paid (470 ) (195 ) Effect of foreign exchange 7,528 (14,975 ) Benefit obligation at end of year $ 447,409 $ 362,805 Change in fair value of plan assets: Fair value of plan assets at beginning of year $ 305,709 $ 304,325 Actual return on plan assets 53,741 (7,419 ) Employer contributions 2,105 31,174 Settlements (74 ) — Transfer in from acquisition 119 — Benefit payments (11,062 ) (8,886 ) Administrative expenses paid (470 ) (195 ) Effect of foreign exchange 7,113 (13,290 ) Fair value of plan assets at end of year $ 357,181 $ 305,709 Net balance sheet liability $ 90,228 $ 57,096 Amounts recognized in balance sheet: Noncurrent assets $ 1,742 $ 3,280 Current liabilities 12,788 1,095 Noncurrent liabilities 79,182 59,281 Amounts recognized in accumulated other comprehensive loss related to the Company’s pension, DCP and ESLIRP plans are as follows: Fiscal Year 2019 2018 (in thousands) Net actuarial loss $ 116,930 $ 93,483 Net prior service cost (credit) (2,096 ) (2,585 ) Net amount recognized $ 114,834 $ 90,898 The accumulated benefit obligation and fair value of plan assets for the Company’s pension, DCP and ESLIRP plans with accumulated benefit obligations in excess of plan assets are as follows: December 28, 2019 December 29, 2018 (in thousands) Accumulated benefit obligation $ 410,243 $ 254,138 Fair value of plan assets 337,344 207,538 The projected benefit obligation and fair value of plan assets for the Company’s pension, DCP and ESLIRP plans with projected benefit obligations in excess of plan assets are as follows: December 28, 2019 December 29, 2018 (in thousands) Projected benefit obligation $ 435,638 $ 273,625 Fair value of plan assets 343,688 213,249 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: December 28, 2019 (in thousands) Amortization of net actuarial loss $ 6,344 Amortization of net prior service credit (501 ) Components of net periodic benefit cost for the Company’s pension, DCP and ESLIRP plans are as follows: Fiscal Year 2019 2018 2017 (in thousands) Service cost $ 2,833 $ 2,612 $ 3,110 Interest cost 11,583 10,850 11,642 Expected return on plan assets (13,005 ) (15,516 ) (14,249 ) Amortization of prior service credit (489 ) (514 ) (496 ) Amortization of net loss 2,250 2,990 3,845 Other 850 910 — Net periodic cost (benefit) $ 4,022 $ 1,332 $ 3,852 Assumptions Weighted-average assumptions used to determine projected benefit obligations are as follows: December 28, 2019 December 29, 2018 Discount rate 2.14 % 3.21 % Rate of compensation increase 2.99 % 3.23 % 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. Specifically for the expected termination of the U.S. Pension Plan, estimated costs of lump sum payments and annuity purchases are reflected in the discount rate. A 25 basis point change across all discount rates changes the projected benefit obligation by approximately $20 million for all Company plans. Weighted-average assumptions used to determine net periodic benefit cost are as follows: December 28, 2019 December 29, 2018 December 30, 2017 Discount rate 3.21 % 2.82 % 3.01 % Expected long-term return on plan assets 4.28 % 5.18 % 5.41 % Rate of compensation increase 3.23 % 3.16 % 3.25 % A 0.5% decrease in the expected rate of return would increase annual pension expense by $1.8 million . In fiscal years 2019 and 2018 , new mortality improvement scales were issued in the U.S. and the United Kingdom (U.K.) reflecting a decline in longevity projection from previous releases the Company adopted, which decreased the Company’s benefit obligations by $2.8 million and $1.7 million as of December 28, 2019 and December 29, 2018 , respectively. 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 asset classes. Plan assets did not include any of the Company’s common stock as of December 28, 2019 or December 29, 2018 . The weighted-average target asset allocations are 24.0% to equity securities, 24.6% to fixed income securities and 51.4% to other securities. The fair value of the Company’s pension plan assets by asset category are as follows: December 28, 2019 December 29, 2018 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total (in thousands) Cash and cash equivalents $ 2,388 $ 1,022 $ — $ 3,410 $ 7,317 $ — $ — $ 7,317 Equity securities (1) 7,621 84,377 — 91,998 72,237 — — 72,237 Debt securities (2) 40,281 89,684 — 129,965 17,147 4,100 — 21,247 Mutual funds (3) 6,324 68,632 — 74,956 86,282 59,984 — 146,266 Other (4) 551 54,787 1,514 56,852 718 56,283 1,641 58,642 Total $ 57,165 $ 298,502 $ 1,514 $ 357,181 $ 183,701 $ 120,367 $ 1,641 $ 305,709 (1) This category comprises equity investments and 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. (2) This category comprises debt investments and securities held by U.S. and non-U.S. pension plans valued at the quoted closing price. For non-U.S. pension plans, the quoted closing price is translated into U.S. dollars using a foreign currency exchange rate at year end. Holdings primarily include investment-grade corporate bonds and U.S. treasuries at various durations. (3) This category comprises non-U.S. mutual funds valued at the net asset value of shares held at year end and translated into U.S. dollars using a foreign currency exchange rate at year end. (4) This category mainly comprises fixed income securities tied to various U.K. government bond yields held by non-US pension plans valued at the net asset value of shares held at year-end, and translated into U.S. dollars using a foreign currency exchange rate at year end. The activity within the Level 3 pension plan assets was non-significant during the periods presented. During fiscal year 2019 , the Company contributed $0.8 million to the pension plans and expects to contribute approximately $11.9 million in fiscal year 2020 . During fiscal year 2019 , the Company contributed $1.3 million directly to certain participants outside of plan assets. Expected benefit payments are estimated using the same assumptions used in determining the Company’s benefit obligation as of December 28, 2019 . 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 fiscal years 2025 through 2029, are as follows. Payments in fiscal year 2020 reflect the estimated payments of approximately $94 million to participants in connection with the U.S. Pension Plan termination and $8 million to an executive officer expected to retire: Fiscal Year Pension Plans (in thousands) 2020 $ 111,848 2021 9,420 2022 10,344 2023 40,911 2024 10,814 2025-2029 59,646 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 28, 2019 and December 29, 2018 , the accumulated benefit obligation related to the plan was $1.1 million and $1.5 million , respectively. The amounts included in other accumulated comprehensive income as well as expenses related to the plan were non-significant for fiscal years 2019 , 2018 and 2017 . 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 fiscal years 2019 , 2018 and 2017 , the costs associated with this defined contribution plan totaled $19.1 million , $13.4 million and $11.6 million , respectively.

STOCK-BASED COMPENSATION

STOCK-BASED COMPENSATION	12 Months Ended
	Dec. 28, 2019
Share-based Payment Arrangement [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 (RSUs), and performance share units (PSUs). During fiscal years 2019 , 2018 and 2017 , 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 years from date of grant. • RSUs, 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 RSUs, recipients are not entitled to cash dividends and have no voting rights on the stock during the vesting period. • 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, 2013 and 2015 (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, RSUs, and performance based stock awards count as 2.3 shares and stock options count as 1.0 share. 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. In May 2016, the Company’s shareholders approved the 2016 Incentive Plan (2016 Plan). The 2016 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 2016 Plan allows a maximum of 6.1 million shares to be awarded, of which restricted stock grants, RSUs, and performance based stock awards count as 2.3 shares and stock options count as 1.0 share. Any stock options and other share-based awards that were granted under prior plans and were outstanding in May 2016 continue in accordance with the terms of the respective plans. In May 2018, the Company’s shareholders approved the 2018 Incentive Plan (2018 Plan). The 2018 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 2018 Plan allows a maximum of 7.2 million shares to be awarded, of which restricted stock grants, RSUs, and performance based stock awards count as 2.3 shares and stock options count as 1.0 share. Any stock options and other share-based awards that were granted under prior plans and were outstanding in May 2018 continue in accordance with the terms of the respective plans. As of December 28, 2019 , approximately 5.8 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 stock-based compensation by the financial statement line item in which it is reflected: Fiscal Year 2019 2018 2017 (in thousands) Cost of revenue $ 9,038 $ 6,285 $ 6,509 Selling, general and administrative 48,233 41,061 37,494 Stock-based compensation, before income taxes 57,271 47,346 44,003 Provision for income taxes (9,465 ) (9,188 ) (13,428 ) Stock-based compensation, net of income taxes $ 47,806 $ 38,158 $ 30,575 No stock-based compensation related costs were capitalized in fiscal years 2019 , 2018 and 2017 . Stock Options The following table summarizes stock option activity under the Company’s stock-based compensation plans: Number of shares Weighted Average Weighted Average Aggregate (in thousands) (in years) (in thousands) Options outstanding as of December 29, 2018 1,556 $ 86.44 Options granted 454 $ 144.42 Options exercised (442 ) $ 78.49 Options canceled (61 ) $ 113.17 Options outstanding as of December 28, 2019 1,507 $ 105.19 2.7 $ 70,459 Options exercisable as of December 28, 2019 390 $ 77.87 1.5 $ 28,897 Options expected to vest as of December 28, 2019 1,117 $ 114.73 3.1 $ 41,562 The fair value of stock options granted was estimated using the Black-Scholes option-pricing model with the following weighted-average assumptions: Fiscal Year 2019 2018 2017 Expected life (in years) 3.6 3.7 3.6 Expected volatility 27 % 25 % 24 % Risk-free interest rate 2.4 % 2.4 % 1.6 % Expected dividend yield 0 % 0 % 0 % The weighted-average grant date fair value of stock options granted was $33.97 , $24.80 and $18.33 for fiscal years 2019 , 2018 and 2017 , respectively. As of December 28, 2019 , the unrecognized compensation cost related to unvested stock options expected to vest was $16.5 million . This unrecognized compensation will be recognized over an estimated weighted-average amortization period of 2.3 years . The total intrinsic value of options exercised during fiscal years 2019 , 2018 and 2017 was $27.0 million , $29.0 million and $30.0 million , respectively, with intrinsic value defined as the difference between the market price on the date of exercise and the exercise price. Restricted Stock Units The following table summarizes the restricted stock units activity for fiscal year 2019 : Restricted Stock Units Weighted (in thousands) December 29, 2018 490 $ 93.80 Granted 221 $ 142.85 Vested (185 ) $ 89.34 Canceled (30 ) $ 115.10 December 28, 2019 496 $ 116.07 As of December 28, 2019 , the unrecognized compensation cost related to shares of unvested RSUs expected to vest was $32.6 million , which is expected to be recognized over an estimated weighted-average amortization period of 2.3 years . The total fair value of RSU grants that vested during fiscal years 2019 , 2018 and 2017 was $16.5 million , $15.5 million and $13.6 million , respectively. Performance Based Stock Award Program The Company issues 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 2019 2018 2017 (shares in thousands) PSUs granted 160 200 198 Weighted average grant date fair value $ 164.47 $ 117.89 $ 99.96 Key Assumptions: Expected volatility 25 % 26 % 26 % Risk-free interest rate 2.4 % 2.4 % 1.3 % Expected dividend yield 0 % 0 % 0 % Total shareholder return of 20-trading day average stock price on grant date 17.7 % 2.9 % 17.7 % The maximum number of common shares to be issued upon vesting of PSUs is 0.3 million . For fiscal years 2019 , 2018 and 2017 , the Company recognized stock-based compensation related to PSUs of $25.3 million , $20.4 million and $18.9 million , respectively. The total fair value of PSUs that vested during fiscal years 2019 , 2018 and 2017 was $20.2 million , $18.3 million and $14.4 million , respectively. In fiscal years 2019 , 2018 and 2017 , the Company also issued approximately 15,000 , 17,000 and 15,000 PSUs using a weighted-average grant date fair value per share of $144.67 , $109.34 and $88.05

FOREIGN CURRENCY CONTRACTS

FOREIGN CURRENCY CONTRACTS	12 Months Ended
	Dec. 28, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
FOREIGN CURRENCY CONTRACTS	FOREIGN CURRENCY CONTRACTS Cross currency loans The Company entered into foreign exchange forward contracts during fiscal 2019 and 2018 to limit its foreign currency exposure related U.S. dollar denominated loans borrowed by a non-U.S. Euro functional currency entity under the Company’s Credit Facility. These contracts are not designated as hedging instruments. Any gains or losses on these forward contracts are recognized immediately within Interest expense in the consolidated statements of income. The Company had no open forward contracts related to a U.S. dollar denominated loan borrowed by a non-U.S. Euro functional currency as of December 28, 2019 . One contract remained open as of December 29, 2018 , which has a duration of approximately 3 months, and is recorded at fair value in the Company’s accompanying consolidated balance sheets. The notional amount and fair value of the open contract is summarized as follows: December 29, 2018 Notional Amount Fair Value Balance Sheet Location (in thousands) $ 343,300 $ (1,319 ) Other current liabilities The following table summarizes the effect of the foreign exchange forward contracts entered into to limit the Company’s foreign currency exposure related to U.S. dollar denominated loans borrowed by a non-U.S. Euro functional currency entity under the Credit Facility on the Company’s consolidated statements of income: Fiscal Year 2019 2018 Location of gain (loss) Financial statement caption amount Amount of gain (loss) Financial statement caption amount Amount of gain (loss) (in thousands) Interest expense $ 60,882 $ 18,672 $ 63,772 1,486 Intercompany loans The Company periodically enters into foreign exchange forward contracts to limit its foreign currency exposure related to certain intercompany loans. These contracts are not designated as hedging instruments. Any gains or losses on forward contracts associated with intercompany loans are recognized immediately in Other income, net and are largely offset by the remeasurement of the underlying intercompany loans. The Company entered into foreign currency forward contracts during 2019 . One contract remained open at December 28, 2019, which had a duration of less than one month and is recorded at fair value in the Company’s accompanying consolidated balance sheets. The Company did not have any significant foreign currency forward contracts related to certain intercompany loans during fiscal years 2018 and 2017 . The notional amount and fair value of the open contract is summarized as follows: December 28, 2019 Notional Amount Fair Value Balance Sheet Location (in thousands) $ 115,038 $ (876 ) Other current liabilities The following table summarizes the effect of the foreign exchange forward contracts in connection with certain intercompany loans on the Company’s consolidated statements of income: Fiscal Year 2019 Location of gain (loss) Financial statement caption amount Amount of gain (loss) (in thousands) Other income, net $ 12,293 $ (121 )

RESTRUCTURING AND ASSET IMPAIRM

RESTRUCTURING AND ASSET IMPAIRMENTS	12 Months Ended
	Dec. 28, 2019
Restructuring and Related Activities [Abstract]
RESTRUCTURING AND ASSET IMPAIRMENTS	RESTRUCTURING AND ASSET IMPAIRMENTS Global Restructuring Initiatives In recent fiscal years, the Company has undertaken productivity improvement initiatives within all reportable segments at various locations across the U.S., Canada, Europe, China, and Japan. This includes workforce right-sizing and scalability initiatives, resulting in severance and transition costs; and cost related to the consolidation of facilities, resulting in asset impairment and accelerated depreciation charges. The Company does not have any significant remaining lease obligations for facilities associated with restructuring activities. The following table presents a summary of restructuring costs related to these initiatives by classification within the consolidated statements of income: Severance and Transition Costs Asset Impairments and Other Costs Total (in thousands) December 28, 2019 Cost of services provided and products sold (excluding amortization of intangible assets) $ 4,348 $ 2,367 $ 6,715 Selling, general and administrative 7,106 18 7,124 Total $ 11,454 $ 2,385 $ 13,839 December 29, 2018 Cost of services provided and products sold (excluding amortization of intangible assets) $ 923 $ 27 $ 950 Selling, general and administrative 6,597 21 6,618 Total $ 7,520 $ 48 $ 7,568 December 30, 2017 Cost of services provided and products sold (excluding amortization of intangible assets) $ 1,944 $ 929 $ 2,873 Selling, general and administrative 1,905 — 1,905 Total $ 3,849 $ 929 $ 4,778 The following table presents restructuring costs by reportable segment for these productivity improvement initiatives: Fiscal Year 2019 2018 2017 (in thousands) RMS $ 3,110 $ — $ 291 DSA 7,307 1,063 1,604 Manufacturing 3,032 1,227 2,883 Unallocated corporate 390 5,278 — Total $ 13,839 $ 7,568 $ 4,778 2017 RMS Restructuring Initiative In the fourth quarter of fiscal year 2017, the Company committed to a plan to further reduce costs and improve operating efficiencies in its RMS reportable segment. The plan included ceasing production within the Company’s facility in Maryland and reducing its workforce at various global RMS facilities during 2018. On August 1, 2018, the Company’s Board of Directors approved a modification to the plan which repurposed the facility in Maryland to be used for alternative initiatives. The Company’s existing lease obligation continues through 2028 and the Company expects to remain in the facility for the duration of the lease term. The following table presents a summary of severance and transition costs, and asset impairments (referred to as restructuring costs) related to this initiative during fiscal years 2018 and 2017 by classification within the consolidated statements of income. The Company did not incur any restructuring costs during fiscal year December 28, 2019 . Severance and Transition Costs Asset Impairments and Other Costs Total (in thousands) December 29, 2018 Cost of services provided and products sold (excluding amortization of intangible assets) $ 847 $ 822 $ 1,669 Selling, general and administrative 314 — 314 Total $ 1,161 $ 822 $ 1,983 December 30, 2017 Cost of services provided and products sold (excluding amortization of intangible assets) $ 362 $ 17,716 $ 18,078 Selling, general and administrative 67 — 67 Total $ 429 $ 17,716 $ 18,145 Restructuring costs incurred during 2017 were $18.1 million , which primarily related to non-cash asset impairments and accelerated depreciation charges of $17.7 million . The costs incurred during 2018 were $2.0 million , which primarily related to cash payments for severance and transition costs of $1.2 million . All of the costs are recorded in the RMS reportable segment. All severance and transition costs have been paid as of December 28, 2019 and no further restructuring costs related to the 2017 RMS Restructuring Initiative are expected to be incurred. Rollforward of restructuring activities The following table provides a rollforward for all of the Company’s severance and transition costs, and certain lease obligation liabilities related to restructuring activities: Fiscal Year 2019 2018 2017 (in thousands) Beginning balance $ 2,921 $ 6,856 $ 8,102 Expense (excluding non-cash charges) 12,674 8,681 4,278 Payments / utilization (9,206 ) (12,341 ) (6,103 ) Foreign currency adjustments 17 (275 ) 579 Ending balance $ 6,406 $ 2,921 $ 6,856 As of December 28, 2019 and December 29, 2018 , $6.3 million and $2.4 million of severance and other personnel related costs liabilities and lease obligation liabilities, respectively, were included in accrued compensation and accrued liabilities within the Company’s consolidated balance sheets and $0.1 million and $0.5 million , respectively, were included in other long-term liabilities within the Company's consolidated balance sheets.

LEASES

LEASES	12 Months Ended
	Dec. 28, 2019
Leases [Abstract]
LEASES	LEASES Adoption of ASC Topic 842, “Leases” (ASC 842) ASC 842 became effective for the Company on December 30, 2018 and was adopted using the modified retrospective method for all leases that had commenced as of the effective date, along with certain available practical expedients. The Company elected to recognize any effects of applying the new standard as a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption, which there were none. In addition, the Company elected to adopt the package of practical expedients permitted under the transition guidance within the new standard. The practical expedient package applied to leases that commenced prior to the effective date of the new standard and permits a reporting entity not to: i) reassess whether any expired or existing contracts are or contain leases, ii) reassess the historical lease classification for any expired or existing leases, and iii) reassess initial direct costs for any existing leases. The reporting results for fiscal year 2019 reflect the application of ASC 842 guidance while the historical results for fiscal year 2018 were prepared under the guidance of ASC 840. The adoption of the new standard did not have a significant impact upon the Company’s consolidated statements of income and cash flows. The adoption of the new standard resulted in the following impact to the consolidated balance sheets: i) no significant change in the carrying values of assets and liabilities related to the Company’s finance leases, previously referred to as capital leases (See Note 9, “Long-Term Debt and Finance Lease Obligations”), ii) the derecognition of assets and related liabilities pertaining to certain build-to-suit arrangements previously accounted for under ASC 840 and recording them under the guidance of ASC 842, and iii) the recording of right-of-use assets and corresponding lease liabilities pertaining to the Company’s operating leases on the consolidated balance sheets, adjusted for existing balances of prepaid rent and deferred rent liabilities as of the transition date. The cumulative effect of applying ASC 842 to all leases that had commenced as of December 29, 2018 was as follows: Balance sheet captions impacted by ASC 842 December 30, 2018 (Prior to adoption of ASC 842) Effect of the adoption of ASC 842 December 30, 2018 (As adjusted) (in thousands) Prepaid assets $ 53,447 $ (4,413 ) (1) $ 49,034 Property, plant and equipment, net 932,877 (23,448 ) (2) 909,429 Operating lease right-of-use assets, net — 134,172 (3) 134,172 Other assets 143,759 (4,989 ) (4) 138,770 Other current liabilities 71,280 15,935 (5) 87,215 Operating lease right-of-use liabilities — 111,570 (6) 111,570 Long-term debt, net and finance leases 1,636,598 (26,183 ) (7) 1,610,415 ASC 842 adoption adjustments: (1) Short term prepaid rent reclassified from Prepaid assets to the Operating lease right-of-use assets, net. (2) Derecognition of approximately $26 million of leased properties, recorded in Property, plant and equipment, net, specifically Construction-in-process, that were recognized under the previously existing build-to-suit accounting (3) Recognition of Operating lease right-of-use assets, net, and adjusted for prepaid rent and deferred rent liability reclassification adjustments identified in adjustments (1) (4) (5) . (4) Long-term prepaid rent reclassified from Other assets to Operating lease right-of-use assets, net. (5) Recognition of short-term portion of the Operating lease right-of-use liabilities offset by reclassification of deferred rent liability to Operating lease right-of-use assets, net. (6) Recognition of long-term portion of the Operating lease right-of-use liabilities. (7) Derecognition of approximately $26 million of Other debt associated with leased properties that were recognized under the previously existing build-to-suit accounting rules. Operating and Finance Leases Right-of-use lease assets and lease liabilities are reported in the Company’s consolidated balance sheets as follows: December 28, 2019 (in thousands) Operating leases Operating lease right-of-use assets, net $ 140,085 Other current liabilities $ 20,357 Operating lease right-of-use liabilities 116,252 Total operating lease liabilities $ 136,609 Finance leases Property, plant and equipment, net $ 32,519 Current portion of long-term debt and finance leases $ 2,997 Long-term debt, net and finance leases 27,530 Total finance lease liabilities $ 30,527 The components of operating and finance lease costs for fiscal year 2019 were as follows: Fiscal Year December 28, 2019 (in thousands) Operating lease costs $ 30,885 Finance lease costs: Amortization of right-of-use assets 4,007 Interest on lease liabilities 1,349 Short-term lease costs 1,056 Variable lease costs 3,161 Sublease income (994 ) Total lease costs $ 39,464 Other information related to leases was as follows: Supplemental cash flow information Fiscal Year December 28, 2019 (in thousands) Cash flows included in the measurement of lease liabilities: Operating cash flows from operating leases $ 27,153 Operating cash flows from finance leases 1,406 Finance cash flows from finance leases 3,766 Non-cash leases activity: Right-of-use lease assets obtained in exchange for new operating lease liabilities $ 24,382 Right-of-use lease assets obtained in exchange for new finance lease liabilities 4,819 Lease term and discount rate As of December 28, 2019 Weighted-average remaining lease term (in years) Operating lease 8.23 Finance lease 12.97 Weighted-average discount rate Operating lease 4.36 Finance lease 4.58 At the lease commencement date, the discount rate implicit in the lease is used to discount the lease liability if readily determinable. If not readily determinable or leases do not contain an implicit rate, the Company’s incremental borrowing rate is used as the discount rate. As of December 28, 2019 , maturities of operating and finance lease liabilities for each of the following five years and a total thereafter were as follows: Operating Leases Finance Leases (in thousands) 2020 $ 25,955 $ 4,308 2021 25,028 3,832 2022 20,614 3,819 2023 16,853 2,929 2024 16,007 2,141 Thereafter 60,371 23,650 Total minimum future lease payments 164,828 40,679 Less: Imputed interest 28,219 10,152 Total lease liabilities $ 136,609 $ 30,527 Total minimum future lease payments (predominantly operating leases) of approximately $57 million for leases that have not commenced as of December 28, 2019 , as the Company does not yet control the underlying assets, are not included in the consolidated financial statements. These leases are expected to commence between fiscal years 2020 and 2024 with lease terms of approximately 4 to 15 years. As of December 29, 2018 , minimum future lease payments under non-cancellable leases for each of the following five years and a total thereafter were as follows: Operating Leases (1) Finance Leases (1) (in thousands) 2019 $ 25,411 $ 3,972 2020 22,400 3,759 2021 21,544 2,869 2022 18,535 2,967 2023 15,398 2,209 Thereafter 66,870 24,304 Total minimum future lease payments $ 170,158 $ 40,080 (1) Lease commitments are presented under the guidance of ASC 840 and includes approximately $14 million of minimum future lease payments for leases that had not commenced as of December 29, 2018. These commitments relate to existing leases for which the Company does not yet control certain expansion space.
LEASES	LEASES Adoption of ASC Topic 842, “Leases” (ASC 842) ASC 842 became effective for the Company on December 30, 2018 and was adopted using the modified retrospective method for all leases that had commenced as of the effective date, along with certain available practical expedients. The Company elected to recognize any effects of applying the new standard as a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption, which there were none. In addition, the Company elected to adopt the package of practical expedients permitted under the transition guidance within the new standard. The practical expedient package applied to leases that commenced prior to the effective date of the new standard and permits a reporting entity not to: i) reassess whether any expired or existing contracts are or contain leases, ii) reassess the historical lease classification for any expired or existing leases, and iii) reassess initial direct costs for any existing leases. The reporting results for fiscal year 2019 reflect the application of ASC 842 guidance while the historical results for fiscal year 2018 were prepared under the guidance of ASC 840. The adoption of the new standard did not have a significant impact upon the Company’s consolidated statements of income and cash flows. The adoption of the new standard resulted in the following impact to the consolidated balance sheets: i) no significant change in the carrying values of assets and liabilities related to the Company’s finance leases, previously referred to as capital leases (See Note 9, “Long-Term Debt and Finance Lease Obligations”), ii) the derecognition of assets and related liabilities pertaining to certain build-to-suit arrangements previously accounted for under ASC 840 and recording them under the guidance of ASC 842, and iii) the recording of right-of-use assets and corresponding lease liabilities pertaining to the Company’s operating leases on the consolidated balance sheets, adjusted for existing balances of prepaid rent and deferred rent liabilities as of the transition date. The cumulative effect of applying ASC 842 to all leases that had commenced as of December 29, 2018 was as follows: Balance sheet captions impacted by ASC 842 December 30, 2018 (Prior to adoption of ASC 842) Effect of the adoption of ASC 842 December 30, 2018 (As adjusted) (in thousands) Prepaid assets $ 53,447 $ (4,413 ) (1) $ 49,034 Property, plant and equipment, net 932,877 (23,448 ) (2) 909,429 Operating lease right-of-use assets, net — 134,172 (3) 134,172 Other assets 143,759 (4,989 ) (4) 138,770 Other current liabilities 71,280 15,935 (5) 87,215 Operating lease right-of-use liabilities — 111,570 (6) 111,570 Long-term debt, net and finance leases 1,636,598 (26,183 ) (7) 1,610,415 ASC 842 adoption adjustments: (1) Short term prepaid rent reclassified from Prepaid assets to the Operating lease right-of-use assets, net. (2) Derecognition of approximately $26 million of leased properties, recorded in Property, plant and equipment, net, specifically Construction-in-process, that were recognized under the previously existing build-to-suit accounting (3) Recognition of Operating lease right-of-use assets, net, and adjusted for prepaid rent and deferred rent liability reclassification adjustments identified in adjustments (1) (4) (5) . (4) Long-term prepaid rent reclassified from Other assets to Operating lease right-of-use assets, net. (5) Recognition of short-term portion of the Operating lease right-of-use liabilities offset by reclassification of deferred rent liability to Operating lease right-of-use assets, net. (6) Recognition of long-term portion of the Operating lease right-of-use liabilities. (7) Derecognition of approximately $26 million of Other debt associated with leased properties that were recognized under the previously existing build-to-suit accounting rules. Operating and Finance Leases Right-of-use lease assets and lease liabilities are reported in the Company’s consolidated balance sheets as follows: December 28, 2019 (in thousands) Operating leases Operating lease right-of-use assets, net $ 140,085 Other current liabilities $ 20,357 Operating lease right-of-use liabilities 116,252 Total operating lease liabilities $ 136,609 Finance leases Property, plant and equipment, net $ 32,519 Current portion of long-term debt and finance leases $ 2,997 Long-term debt, net and finance leases 27,530 Total finance lease liabilities $ 30,527 The components of operating and finance lease costs for fiscal year 2019 were as follows: Fiscal Year December 28, 2019 (in thousands) Operating lease costs $ 30,885 Finance lease costs: Amortization of right-of-use assets 4,007 Interest on lease liabilities 1,349 Short-term lease costs 1,056 Variable lease costs 3,161 Sublease income (994 ) Total lease costs $ 39,464 Other information related to leases was as follows: Supplemental cash flow information Fiscal Year December 28, 2019 (in thousands) Cash flows included in the measurement of lease liabilities: Operating cash flows from operating leases $ 27,153 Operating cash flows from finance leases 1,406 Finance cash flows from finance leases 3,766 Non-cash leases activity: Right-of-use lease assets obtained in exchange for new operating lease liabilities $ 24,382 Right-of-use lease assets obtained in exchange for new finance lease liabilities 4,819 Lease term and discount rate As of December 28, 2019 Weighted-average remaining lease term (in years) Operating lease 8.23 Finance lease 12.97 Weighted-average discount rate Operating lease 4.36 Finance lease 4.58 At the lease commencement date, the discount rate implicit in the lease is used to discount the lease liability if readily determinable. If not readily determinable or leases do not contain an implicit rate, the Company’s incremental borrowing rate is used as the discount rate. As of December 28, 2019 , maturities of operating and finance lease liabilities for each of the following five years and a total thereafter were as follows: Operating Leases Finance Leases (in thousands) 2020 $ 25,955 $ 4,308 2021 25,028 3,832 2022 20,614 3,819 2023 16,853 2,929 2024 16,007 2,141 Thereafter 60,371 23,650 Total minimum future lease payments 164,828 40,679 Less: Imputed interest 28,219 10,152 Total lease liabilities $ 136,609 $ 30,527 Total minimum future lease payments (predominantly operating leases) of approximately $57 million for leases that have not commenced as of December 28, 2019 , as the Company does not yet control the underlying assets, are not included in the consolidated financial statements. These leases are expected to commence between fiscal years 2020 and 2024 with lease terms of approximately 4 to 15 years. As of December 29, 2018 , minimum future lease payments under non-cancellable leases for each of the following five years and a total thereafter were as follows: Operating Leases (1) Finance Leases (1) (in thousands) 2019 $ 25,411 $ 3,972 2020 22,400 3,759 2021 21,544 2,869 2022 18,535 2,967 2023 15,398 2,209 Thereafter 66,870 24,304 Total minimum future lease payments $ 170,158 $ 40,080 (1) Lease commitments are presented under the guidance of ASC 840 and includes approximately $14 million of minimum future lease payments for leases that had not commenced as of December 29, 2018. These commitments relate to existing leases for which the Company does not yet control certain expansion space.

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	12 Months Ended
	Dec. 28, 2019
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Insurance The Company maintains certain insurance policies that maintain large deductibles up to approximately $1.0 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. 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. Purchase Obligations The Company enters into unconditional purchase obligations, in the ordinary course of business, that include agreements to purchase goods or services that are enforceable and legally binding and that specify all significant terms including: fixed or minimum quantities to be purchased; fixed, minimum or variable price provisions; and the approximate timing of the transaction. Purchase obligations exclude agreements that are cancellable at any time without penalty. The aggregate amount of the Company’s unconditional purchase obligations totaled $154.0 million as of December 28, 2019 and is expected to be paid as follows: Payments Due by Period Less than 1 - 3 Years 3 - 5 Years Total (in millions) Unconditional purchase obligations $ 106.1 $ 45.0 $ 2.9 $ 154.0

SELECTED QUARTERLY FINANCIAL DA

SELECTED QUARTERLY FINANCIAL DATA (unaudited)	12 Months Ended
	Dec. 28, 2019
Quarterly Financial Information Disclosure [Abstract]
SELECTED QUARTERLY FINANCIAL DATA (unaudited)	SELECTED QUARTERLY FINANCIAL DATA (unaudited) The following table contains quarterly financial information for fiscal years 2019 and 2018 . The operating results for any quarter are not necessarily indicative of future period results. First Quarter Second Quarter Third Quarter Fourth Quarter (in thousands, except per share amounts) Fiscal Year 2019 Total revenue $ 604,569 $ 657,568 $ 667,951 $ 691,138 Gross profit (1) 211,777 238,104 246,116 262,314 Operating income 69,792 79,768 92,802 108,789 Net income attributable to common shareholders 55,133 43,728 72,810 80,348 Earnings per common share Basic: Continuing operations attributable to common shareholders $ 1.14 $ 0.90 $ 1.49 $ 1.64 Discontinued operations $ — $ — $ — $ — Net income attributable to common shareholders $ 1.14 $ 0.90 $ 1.49 $ 1.64 Diluted: Continuing operations attributable to common shareholders $ 1.11 $ 0.88 $ 1.46 $ 1.61 Discontinued operations $ — $ — $ — $ — Net income attributable to common shareholders $ 1.11 $ 0.88 $ 1.46 $ 1.61 Fiscal Year 2018 Total revenue $ 493,970 $ 585,301 $ 585,295 $ 601,530 Gross profit (1) 181,469 215,981 216,200 226,417 Operating income 67,829 76,710 84,362 102,482 Net income attributable to common shareholders 52,631 53,709 60,368 59,665 Earnings per common share Basic: Continuing operations attributable to common shareholders $ 1.10 $ 1.08 $ 1.25 $ 1.24 Discontinued operations $ — $ 0.03 $ — $ — Net income attributable to common shareholders $ 1.10 $ 1.11 $ 1.25 $ 1.24 Diluted: Continuing operations attributable to common shareholders $ 1.08 $ 1.06 $ 1.22 $ 1.21 Discontinued operations $ — $ 0.03 $ — $ — Net income attributable to common shareholders $ 1.08 $ 1.10 $ 1.22 $ 1.21 (1) Gross profit is calculated as total revenue minus cost of revenue (excluding amortization of intangible assets). Full-year amounts may not sum due to rounding.

DESCRIPTION OF BUSINESS AND S_2

DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 28, 2019
Organization, Consolidation and Presentation of Financial Statements [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 year is typically based on 52-week s , with each quarter comp osed of 13 weeks ending on the last Saturday on, or closest to, March 31, June 30, September 30, and December 31.
Segment Reporting	Segment Reporting The Company reports its results in three reportable segments: Research Models and Services (RMS), Discovery and Safety Assessment (DSA), and Manufacturing Support (Manufacturing). The Company’s RMS reportable segment includes the Research Models and Research Model Services businesses. Research Models includes the commercial production and sale of small research models, as well as the supply of large research models. Research Model Services includes: Genetically Engineered Models and Services (GEMS), which performs contract breeding and other services associated with genetically engineered models; Research Animal Diagnostic Services (RADS), which provides health monitoring and diagnostics services related to research models; and Insourcing Solutions (IS), which provides colony management of its clients’ research operations (including recruitment, training, staffing, and management services). The Company’s DSA reportable segment includes services required to take a drug through the early development process including discovery services, which are non-regulated services to assist clients with the identification, screening, and selection of a lead compound for drug development, and regulated and non-regulated (GLP and non-GLP) safety assessment services. The Company’s Manufacturing reportable segment includes Microbial Solutions, which provides in vitro (non-animal) lot-release testing products, microbial detection products, and species identification services; Biologics Testing Services (Biologics), which performs specialized testing of biologics; Avian Vaccine Services (Avian), which supplies specific-pathogen-free chicken eggs and chickens; and contract development and manufacturing (CDMO) services, which, until the Company divested this business on February 10, 2017, allowed it to provide formulation design and development, manufacturing, and analytical and stability testing for small molecules.
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 make 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, Cash Equivalents, and 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 in fiscal years 2019 , 2018 , or 2017 or trade receivables as of December 28, 2019 or December 29, 2018 .
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 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 and 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 market prices determined through third-party pricing services; • Foreign currency forward contracts - Valued using market observable inputs, such as forward foreign exchange points and foreign exchanges rates; • Life insurance policies - Valued at cash surrender value based on the fair value of underlying investments; • Debt instruments - The book value of the Company’s term and revolving loans, which are variable rate loans carried at amortized cost, approximates the fair value based on current market pricing of similar debt. The book value of the Company’s 5.5% Senior Notes due in 2026 and the 4.25% Senior Notes due in 2028 (Senior Notes), which are fixed rate debt, are carried at amortized cost. Fair value of the Senior Notes is based on quoted market prices and on borrowing rates available to the Company; and • Contingent consideration - Valued based on a probability weighting of the future cash flows associated with the potential outcomes.
Inventories	Inventories The Company’s inventories consist of raw materials, work in process and finished product related primarily to small models, large models, microbial solutions products, and avian related eggs and flocks. Inventories are stated at the lower of cost or net realizable value. Inventory value is generally based on the standard cost method for all businesses except for the Avian business, which is based on an average cost. Standard costs are trued-up to reflect actual cost . For small models inventory, costs include 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 models inventory, costs are primarily the external cost paid to acquire the model. For the microbial solutions inventory, costs include direct materials, cost of personnel directly involved in the manufacturing and assembly of products sold, and an allocation of facility overhead. For the avian related inventory, costs include direct materials, such as animal feed, cost of personnel directly involved with the care of the eggs and flocks, and an allocation of facility overhead. 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, net, 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 follow: 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. Finance lease assets are amortized over the lease term, however, if ownership is transferred by the end of the finance lease, or there is a bargain purchase option, such finance 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 Combinations The Company accounts for business combinations 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, which typically represents a significant portion of the purchase price. The determination of the fair value of intangible assets requires the use of significant judgment using management’s best estimates of inputs and assumptions that a market participant would use. Significant judgments include (i) the fair value; and (ii) whether such intangible assets are amortizable or non-amortizable and, if the former, the period and the method by which the intangible asset will be amortized. The Company utilizes commonly accepted valuation techniques, such as the income approach and the cost approach, as appropriate, in establishing the fair value of intangible assets. Typically, key assumptions include projections of cash flows that arise from identifiable intangible assets of acquired businesses as well as discount rates based on an analysis of the weighted average cost of capital, adjusted for specific risks associated with the assets. In recent acquisitions, customer relationship intangible assets (also referred to as client relationships) are the most significant identifiable asset acquired. To determine the fair value of the acquired client relationships, the Company typically utilizes the multiple period excess earnings model (a commonly accepted valuation technique), which relies on the following key assumptions: projections of cash flows from the acquired entities, which includes future revenue growth rates, operating income margins, and customer attrition rates; as well as discount rates based on an analysis of the acquired entities’ weighted average cost of capital. 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 the 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 7, “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 acquisition 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 amortized over the pattern in which the economic benefits of the intangible assets are utilized and 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.
Venture Capital Investments	Venture Capital Investments The Company invests in several venture capital funds that invest in start-up companies, primarily in the life sciences industry. The Company’s ownership interest in these funds ranges from less than 1% to approximately 12% . The Company accounts for the investments in limited partnerships (LPs), which are variable interest entities, under the equity method of accounting. For publicly-held investments in the LPs, the Company adjusts for changes in fair market value based on reported share holdings at the end of each fiscal quarter. The Company is not the primary beneficiary because it has no power to direct the activities that most significantly affect the LPs’ economic performance. The Company accounts for the investments in limited liability companies, which are not variable interest entities, under the equity method of accounting. Under the equity method of accounting, the Company’s 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, net in the accompanying consolidated statements of income. 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 are 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
Leases	Leases At inception of a contract, the Company determines if a contract meets the definition of a lease. A lease is a contract, or part of a contract, that conveys the right to control the use of identified property, plant, or equipment (an identified asset) for a period of time in exchange for consideration. The Company determines if the contract conveys the right to control the use of an identified asset for a period of time. The Company assesses throughout the period of use whether the Company has both of the following: (1) the right to obtain substantially all of the economic benefits from use of the identified asset, and (2) the right to direct the use of the identified asset. This determination is reassessed if the terms of the contract are changed. Leases are classified as operating or finance leases based on the terms of the lease agreement and certain characteristics of the identified asset. Right-of-use assets and lease liabilities are recognized at lease commencement date based on the present value of the minimum future lease payments. The Company leases laboratory, production, and office space (real estate), as well as land, vehicles and certain equipment under non-cancellable operating and finance leases. The carrying value of the Company’s right-of-use lease assets is substantially concentrated in its real estate leases, while the volume of lease agreements is primarily concentrated in vehicles and equipment leases. The Company’s policy is to not record leases with an original term of twelve months or less on the consolidated balance sheets. The Company recognizes lease expense for these short-term leases on a straight-line basis over the lease term. Certain lease agreements include rental payments that are adjusted periodically for inflation or other variables. In addition to rent, the leases may require the Company to pay additional amounts for taxes, insurance, maintenance and other expenses, which are generally referred to as non-lease components. Such adjustments to rental payments and variable non-lease components are treated as variable lease payments and recognized in the period in which the obligation for these payments was incurred. Variable lease components and variable non-lease components are not measured as part of the right-of-use asset and liability. Only when lease components and their associated non-lease components are fixed are they accounted for as a single lease component and are recognized as part of a right-of-use asset and liability. Total contract consideration is allocated to the combined fixed lease and non-lease component. This policy election applies consistently to all asset classes under lease agreements. Most leases contain clauses for renewal at the Company’s option with renewal terms that generally extend the lease term from 1 to 5 years . Certain lease agreements contain options to purchase the leased property and options to terminate the lease. Payments to be made in option periods are recognized as part of the right-of-use lease assets and lease liabilities when it is reasonably certain that the option to extend the lease will be exercised or the option to terminate the lease will not be exercised, or is not at the Company’s option. The Company determines whether the reasonably certain threshold is met by considering contract-, asset-, market-, and entity-based factors. A portfolio approach is applied to certain lease contracts with similar characteristics. The Company’s lease agreements do not contain any significant residual value guarantees or material restrictive covenants imposed by the leases. The Company subleases a limited number of lease arrangements. Sublease activity is not material to the consolidated financial statements.
Stock-Based Compensation	Stock-Based Compensation The Company may grant stock options, restricted stock, restricted stock units (RSUs), and performance share units (PSUs) to employees and stock options, restricted stock, and RSUs to non-employee directors under stock-based compensation plans. Stock-based compensation is recognized as an expense in the consolidated statements of income based on the grant date fair value, adjusted for forfeitures when they occur, over the requisite service period. For stock options, restricted stock and RSUs 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 and a portion of the award continues to vest after the employee’s eligible 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 RSUs is based on the market value of the Company’s common stock on the date of grant.
Revenue Recognition	Revenue Recognition Accounting Standard Codification Topic 606, “Revenue from Contracts with Customers” (ASC 606) became effective for the Company on December 31, 2017 and was adopted using the modified retrospective method for all contracts not completed as of the date of adoption. For contracts that were modified before the effective date, the Company reflected the aggregate effect of all modifications when identifying performance obligations and allocating transaction price in accordance with the practical expedient, which did not have a material effect on the cumulative impact of adopting ASC 606. The reported results for fiscal years 2019 and 2018 reflect the application of ASC 606 guidance while the historical results for fiscal year 2017 was prepared under the guidance of ASC 605, “Revenue Recognition” (ASC 605). There is no material difference in the reporting of revenue during fiscal years 2019 and 2018 in accordance with ASC 606 when compared to fiscal year 2017 in accordance with ASC 605. Revenue is recognized when, or as, obligations under the terms of a contract are satisfied, which occurs when control of the promised products or services is transferred to customers. Revenue is measured as the amount of consideration the Company expects to receive in exchange for transferring products or services to a customer (“transaction price”). To the extent the transaction price includes variable consideration, the Company estimates the amount of variable consideration that should be included in the transaction price utilizing the amount to which the Company expects to be entitled. Variable consideration is included in the transaction price if, in the Company’s judgment, it is probable that a significant future reversal of cumulative revenue under the contract will not occur. Estimates of variable consideration and determination of whether to include estimated amounts in the transaction price are based largely on an assessment of the Company’s anticipated performance and all information (historical, current and forecasted) that is reasonably available. Sales, value add, and other taxes collected on behalf of third parties are excluded from revenue. When determining the transaction price of a contract, an adjustment is made if payment from a customer occurs either significantly before or significantly after performance, resulting in a significant financing component. Generally, the Company does not extend payment terms beyond one year. Applying the practical expedient, the Company does not assess whether a significant financing component exists if the period between when the Company performs its obligations under the contract and when the customer pays is one year or less. The Company’s contracts do not generally contain significant financing components. Contracts with customers may contain multiple performance obligations. For such arrangements, the transaction price is allocated to each performance obligation based on the estimated relative standalone selling prices of the promised products or services underlying each performance obligation. The Company determines standalone selling prices based on the price at which the performance obligation is sold separately. If the standalone selling price is not observable through past transactions, the Company estimates the standalone selling price taking into account available information such as market conditions and internally approved pricing guidelines related to the performance obligations. Contracts are often modified to account for changes in contract specifications and requirements. Contract modifications exist when the modification either creates new, or changes existing, enforceable rights and obligations. Generally, when contract modifications create new performance obligations, the modification is considered to be a separate contract and revenue is recognized prospectively. When contract modifications change existing performance obligations, the existing transaction price and measure of progress for the performance obligation to which it relates is generally recognized as an adjustment to revenue (either as an increase in or a reduction of revenue) on a cumulative catch-up basis. Product revenue is generally recognized when the customer obtains control of the Company’s product, which occurs at a point in time, and may be upon shipment or upon delivery based on the contractual shipping terms of a contract. Service revenue is generally recognized over time as the services are delivered to the customer based on the extent of progress towards completion of the performance obligation. The selection of the method to measure progress towards completion requires judgment and is based on the nature of the products or services to be provided. Depending on which better depicts the transfer of value to the customer, the Company generally measures its progress using either cost-to-cost (input method) or right-to-invoice (output method). The Company uses the cost-to-cost measure of progress when it best depicts the transfer of value to the customer which occurs as the Company incurs costs on its contract, generally related to fixed fee service contracts. Under the cost-to-cost measure of progress, the extent of progress towards completion is measured based on the ratio of costs incurred to date to the total estimated costs at completion of the performance obligation. The costs calculation includes variables such as labor hours, allocation of overhead costs, research model costs, and subcontractor costs. Revenue is recorded proportionally as costs are incurred. The right-to-invoice measure of progress is generally related to rate per unit contracts, as the extent of progress towards completion is measured based on discrete service or time-based increments, such as samples tested or labor hours incurred. Revenue is recorded in the amount invoiced since that amount corresponds directly to the value of the Company’s performance to date.
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 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 and Translation of Foreign Currencies	Foreign Currency Contracts Foreign currency contracts are recorded at fair value in the Company’s consolidated balance sheets and are not designated as hedging instruments. Any gains or losses on forward contracts associated with intercompany loans are recognized immediately in Other income, net and are largely offset by the remeasurement of the underlying intercompany loan. Any gains or losses on forward contracts associated with the Company’s U.S. dollar denominated loan borrowed by a non-U.S. entity under the Company’s Credit Facility are recognized immediately in Interest expense. Gains or losses incurred on the remeasurement of the Company’s U.S. dollar denominated loan borrowed by a non-U.S. entity with a different functional currency is recorded in Other income, 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 as of 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 the Company’s foreign operations into U.S. dollars are excluded from the determination of net income and are recorded in accumulated other comprehensive 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 a 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. 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. The Company records the service cost component of the net periodic benefit cost within Cost of services provided and Selling, general, and administrative expenses (within Operating income) and all other components of net periodic benefit cost within Other income, net in the consolidated statements of income. The Company recognizes pension settlement gains or losses in the period when all of the following settlement criteria are met: there is an irrevocable action, the Company is relieved of primary responsibility for a benefit obligation, and significant risks related to the obligation and the assets used to effect the settlement are eliminated. Refer to Note 12. “Employee Benefit Plans” for further discussion of the U.S. Pension Plan termination and expected settlement in fiscal 2020.
Earnings Per Share	Earnings Per Share Basic earnings per share is 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, RSUs, or PSUs, as well as their related income tax effects.
Treasury Shares	Treasury Shares The Company periodically retires treasury shares acquired through share repurchases and returns those shares to the status of authorized but unissued. The Company accounts for treasury stock transactions under the cost method. For each reacquisition of common stock, the number of shares and the acquisition price for those shares is added to the existing treasury stock count and total value. Thus, the average cost per share is re-averaged each time shares are acquired. When treasury shares are retired, the Company allocates the excess of the repurchase price over the par value of shares acquired to both retained earnings and additional paid-in-capital. The portion allocated to additional paid-in-capital is determined by applying a percentage, determined by dividing the number of shares to be retired by the number of shares issued, to the balance of additional paid-in-capital as of the retirement date.
Newly Adopted and Newly Issued Accounting Pronouncements	. Treasury Shares The Company periodically retires treasury shares acquired through share repurchases and returns those shares to the status of authorized but unissued. The Company accounts for treasury stock transactions under the cost method. For each reacquisition of common stock, the number of shares and the acquisition price for those shares is added to the existing treasury stock count and total value. Thus, the average cost per share is re-averaged each time shares are acquired. When treasury shares are retired, the Company allocates the excess of the repurchase price over the par value of shares acquired to both retained earnings and additional paid-in-capital. The portion allocated to additional paid-in-capital is determined by applying a percentage, determined by dividing the number of shares to be retired by the number of shares issued, to the balance of additional paid-in-capital as of the retirement date. Newly Adopted Accounting Pronouncements In June 2018, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2018-07, “Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting.” ASU 2018-07 aligns the accounting for share-based payment awards issued to employees and nonemployees as well as improves financial reporting for share-based payments to nonemployees. The Company’s adoption of this standard in fiscal year 2019 did not have a significant impact on the consolidated financial statements and related disclosures. In August 2017, the FASB issued ASU 2017-12, “Derivatives and Hedging (Topic 815) Targeted Improvements to Accounting for Hedging Activities.” ASU 2017-12 refines and expands hedge accounting for both financial and commodity risks. It also creates more transparency around how economic results are presented, both on the face of the financial statements and in the disclosures. In addition, this ASU makes certain targeted improvements to simplify the application of hedge accounting guidance. The Company’s adoption of this standard in fiscal year 2019 did not have a significant impact on the consolidated financial statements and related disclosures. In February 2016, the FASB issued ASU 2016-02, “Leases.” The standard, including subsequently issued amendments, collectively referred to as Accounting Standards Codification (ASC) 842, “Leases”, established the principles that lessees and lessors will apply to report useful information to users of financial statements about the amount, timing and uncertainty of cash flows arising from a lease. The Company adopted this standard using the modified retrospective transition approach as applied to leases existing as of or entered into after the adoption date (December 30, 2018) in fiscal year 2019. See Note 16, “Leases” for a discussion of the Company’s adoption of this standard and its impact on the consolidated financial statements and related disclosures. Newly Issued Accounting Pronouncements In January 2020, the FASB issued ASU 2020-01, “Investments-Equity Securities (Topic 321), Investments-Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815).” ASU 2020-01 states any equity security transitioning from the alternative method of accounting under Topic 321 to the equity method, or vice versa, due to an observable transaction will be remeasured immediately before the transition. In addition, the ASU clarifies the accounting for certain non-derivative forward contracts or purchased call options to acquire equity securities stating such instruments will be measured using the fair value principles of Topic 321 before settlement or exercise. The ASU is effective for fiscal years beginning after December 15, 2020, and will be applied on a prospective basis. Early adoption is permitted. The Company is still evaluating the impact this standard will have on its consolidated financial statements and related disclosures, but does not believe there will be a material impact upon adoption. In December 2019, the FASB issued ASU 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes.” ASU 2019-12 simplifies the accounting for income taxes by removing exceptions within the general principles of Topic 740 regarding the calculation of deferred tax liabilities, the incremental approach for intraperiod tax allocation, and calculating income taxes in an interim period. In addition, the ASU adds clarifications to the accounting for franchise tax (or similar tax). which is partially based on income, evaluating tax basis of goodwill recognized from a business combination, and reflecting the effect of any enacted changes in tax laws or rates in the annual effective tax rate computation in the interim period that includes the enactment date. The ASU is effective for fiscal years beginning after December 15, 2020, and will be applied either retrospectively or prospectively based upon the applicable amendments. Early adoption is permitted. The adoption of this standard is not expected to have a material impact on the Company’s consolidated financial statements and related disclosures. In August 2018, the FASB issued ASU 2018-15, “Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computer Arrangement that is a Service Contract.” ASU 2018-15 aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The ASU is effective for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years and will be applied either retrospectively or prospectively. Early adoption is permitted. The adoption of this standard is not expected to have a material impact on the Company’s consolidated financial statements and related disclosures. In August 2018, the FASB issued ASU 2018-14, “Compensation Retirement Benefits - Defined Benefit Plans - General (Subtopic 715-20).” ASU 2018-14 removes the requirements to disclose the amounts in Accumulated other comprehensive income (loss) expected to be recognized as components of net periodic benefit cost over the next fiscal year and the related party disclosures about the amount of future annual benefits covered by insurance contracts. In addition, the ASU adds the requirement to disclose an explanation for any significant gains and losses related to changes in the benefit obligation for the period. The ASU is effective for fiscal years ending after December 15, 2020 and will be applied on a retrospective basis to all periods presented. Early adoption is permitted. The adoption of this standard is not expected to have a material impact on the Company’s consolidated financial statements and related disclosures. In August 2018, the FASB issued ASU 2018-13, “Fair Value Measurement (Topic 820) - Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement.” ASU 2018-13 removes the disclosure requirement for the amount and reasons for transfers between Level 1 and Level 2 fair value measurements as well as the process for Level 3 fair value measurements. In addition, the ASU adds the disclosure requirements for changes in unrealized gains and losses included in Other comprehensive income (loss) for recurring Level 3 fair value measurements held at the end of the reporting period as well as the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements. The ASU is effective for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years and will be applied on a retrospective basis to all periods presented. Early adoption is permitted. The adoption of this standard is not expected to have a material impact on the Company’s consolidated financial statements and related disclosures. In January 2017, the FASB issued ASU 2017-04, “Simplifying the Test for Goodwill Impairment.” The standard simplifies the accounting for goodwill impairment by removing Step 2 of the goodwill impairment test, which requires a hypothetical purchase price allocation. This standard is effective for annual or interim goodwill impairment tests in fiscal years beginning after December 15, 2019, and will be applied on a prospective basis. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The adoption of this standard is not expected to have a material impact on the Company’s consolidated financial statements and related disclosures. In June 2016, the FASB issued ASU 2016-13, “Financial Instruments - Credit Losses.” The standard, including subsequently issued amendments, requires a financial asset measured at amortized cost basis, such as accounts receivable and certain other financial assets, to be presented at the net amount expected to be collected based on relevant information about past events, including historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amount. This ASU is effective for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years, and requires the modified retrospective approach. Early adoption is permitted. Based on the composition of the Company’s trade receivables and other financial assets, current market conditions, and historical credit loss activity, the adoption of this standard is not expected to have a material impact on the Company’s consolidated financial statements and related disclosures.

DESCRIPTION OF BUSINESS AND S_3

DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	12 Months Ended
	Dec. 28, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Property, Plant, and Equipment Estimated 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 follow: 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 COMBINATIONS AND DIV_2

BUSINESS COMBINATIONS AND DIVESTITURE (Tables)	12 Months Ended
	Dec. 28, 2019
Business Combinations [Abstract]
Schedule of Business Acquisitions, by Acquisition	The purchase price allocation of $21.5 million , net of $1.0 million of cash acquired and a final net working capital adjustment of $0.4 million , was as follows: January 11, 2018 (in thousands) Trade receivables (contractual amount of $1,309) $ 1,309 Other current assets (excluding cash) 99 Property, plant and equipment 1,136 Definite-lived intangible assets - client relationships 3,647 Goodwill 17,660 Current liabilities (1,575 ) Deferred revenue (151 ) Long-term liabilities (596 ) Total purchase price allocation $ 21,529 The purchase allocation of $800.8 million , net of $27.7 million of cash acquired and a final net working capital adjustment of $1.2 million , was as follows: April 3, 2018 (in thousands) Trade receivables (contractual amount of $35,073) $ 35,073 Inventories 4,463 Other current assets (excluding cash) 5,893 Property, plant and equipment 128,403 Goodwill 441,656 Definite-lived intangible assets 309,200 Other long-term assets 1,081 Deferred revenue (23,926 ) Current liabilities (32,885 ) Deferred tax liabilities (65,945 ) Other long-term liabilities (2,213 ) Total purchase price allocation $ 800,800 The purchase price allocation of $20.1 million , net of $0.6 million of cash acquired, was as follows: August 4, 2017 (in thousands) Trade receivables (contractual amount of $1,146) $ 1,146 Other current assets (excluding cash) 640 Property, plant and equipment 664 Other long-term assets 29 Definite-lived intangible assets 9,300 Goodwill 12,582 Current liabilities (1,683 ) Deferred revenue (405 ) Long-term liabilities (2,151 ) Total purchase price allocation $ 20,122 The preliminary purchase allocation of $23.1 million , net of $0.3 million of cash acquired was as follows: August 28, 2019 (in thousands) Trade receivables (contractual amount of $189) $ 189 Inventories 7,644 Property, plant and equipment 1,462 Goodwill 12,669 Other long-term assets 11,849 Current liabilities (441 ) Deferred tax liabilities (1,331 ) Other long-term liabilities (238 ) Redeemable noncontrolling interest (8,740 ) Total purchase price allocation $ 23,063 The preliminary purchase allocation of $491.0 million , net of $36.7 million of cash acquired was as follows: April 29, 2019 (in thousands) Trade receivables (contractual amount of $35,405) $ 35,405 Inventories 5,282 Other current assets (excluding cash) 13,917 Property, plant and equipment 88,605 Goodwill 280,711 Definite-lived intangible assets 162,400 Other long-term assets 20,163 Deferred revenue (15,278 ) Current liabilities (46,081 ) Deferred tax liabilities (27,458 ) Other long-term liabilities (22,624 ) Redeemable noncontrolling interest (4,035 ) Total purchase price allocation $ 491,007
Schedule of Finite-Lived Intangible Assets Acquired	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 $ 134,600 13 Developed technology 19,900 3 Backlog 7,900 1 Total definite-lived intangible assets $ 162,400 12 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 $ 7,000 13 Other intangible assets 2,300 10 Total definite-lived intangible assets $ 9,300 12 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 $ 264,900 13 Developed technology 23,400 3 Backlog 20,900 1 Total definite-lived intangible assets $ 309,200 12
Schedule of Pro Forma Information	For fiscal year 2018 , these adjustments included additional amortization of intangible assets and depreciation of fixed assets of $9.4 million , additional interest expense on borrowings of $4.1 million , elimination of intercompany activity and other one-time costs, and the tax impacts of these adjustments. Fiscal Year 2019 2018 (in thousands) (unaudited) Revenue $ 2,683,610 $ 2,442,283 Net income attributable to common shareholders 268,995 233,288 For fiscal year 2018 , these adjustments included additional amortization of intangible assets and depreciation of fixed assets of $14.1 million , additional interest expense on borrowings of $2.8 million , elimination of intercompany activity and other one-time costs, and the tax impacts of these adjustments. For fisc al year 2017 , these adjustments included additional amortization of intangible assets and depreciation of fixed assets of $22.4 million , additional interest expense on borrowings of $27.1 million , elimination of intercompany activity and other one-time costs, and the tax impacts of these adjustments. Fiscal Year 2018 2017 (in thousands) (unaudited) Revenue $ 2,328,213 $ 2,095,385 Net income attributable to common shareholders 225,550 126,641
Schedule of Carrying Amounts of Assets and Liabilities	The carrying amounts of the major classes of assets and liabilities associated with the divestiture of the CDMO business were as follows: February 10, 2017 (in thousands) Assets Current assets $ 5,505 Property, plant and equipment, net 11,174 Goodwill 35,857 Long-term assets 17,154 Total assets $ 69,690 Liabilities Deferred revenue $ 4,878 Other current liabilities 1,158 Total liabilities $ 6,036

REVENUE FROM CONTRACTS WITH C_2

REVENUE FROM CONTRACTS WITH CUSTOMERS (Tables)	12 Months Ended
	Dec. 28, 2019
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following tables disaggregate the Company’s revenue by major business line and timing of transfer of products or services: Major Products/Service Lines: 2019 2018 (in thousands) RMS $ 537,089 $ 519,682 DSA 1,618,995 1,316,854 Manufacturing 465,142 429,560 Total revenue $ 2,621,226 $ 2,266,096 Timing of Revenue Recognition: 2019 2018 (in thousands) RMS Services and products transferred over time $ 227,872 $ 202,872 Services and products transferred at a point in time 309,217 316,810 DSA Services and products transferred over time 1,618,281 1,316,005 Services and products transferred at a point in time 714 849 Manufacturing Services and products transferred over time 142,896 128,287 Services and products transferred at a point in time 322,246 301,273 Total revenue $ 2,621,226 $ 2,266,096 Revenue for each significant product or service offering is as follows : 2019 2018 2017 (in thousands) RMS $ 537,089 $ 519,682 $ 493,615 DSA 1,618,995 1,316,854 980,022 Manufacturing 465,142 429,560 383,964 Total revenue $ 2,621,226 $ 2,266,096 $ 1,857,601
Schedule of Estimated Revenue Related to Performance Obligations	The following table includes estimated revenue expected to be recognized in the future related to performance obligations that are unsatisfied (or partially satisfied) as of December 28, 2019 : Revenue Expected to be Recognized in Future Periods Less than 1 Year 1 to 3 Years 4 to 5 Years Beyond 5 Years Total (in thousands) DSA $ 156,125 $ 89,458 $ 5,965 $ 527 $ 252,075 Manufacturing 11,604 11,816 19 13 23,452 Total $ 167,729 $ 101,274 $ 5,984 $ 540 $ 275,527
Schedule of Client Receivables, Contract Assets and Contract Liabilities	The following table provides information about client receivables, contract assets, and contract liabilities from contracts with customers: December 28, 2019 December 29, 2018 (in thousands) Balances from contracts with customers: Client receivables $ 395,740 $ 370,131 Contract assets (unbilled revenue) 121,957 105,216 Contract liabilities (current and long-term deferred revenue) 192,788 179,559 Contract liabilities (customer contract deposits) 33,080 38,245

SEGMENT AND GEOGRAPHIC INFORM_2

SEGMENT AND GEOGRAPHIC INFORMATION (Tables)	12 Months Ended
	Dec. 28, 2019
Segment Reporting [Abstract]
Revenue and Other Financial Information by Reportable Segment	The following table presents revenue and other financial information by reportable segment: 2019 2018 2017 (in thousands) RMS Revenue $ 537,089 $ 519,682 $ 493,615 Operating income 133,912 136,468 114,588 Depreciation and amortization 19,197 19,469 19,627 Capital expenditures 26,989 35,172 20,879 DSA Revenue $ 1,618,995 $ 1,316,854 $ 980,022 Operating income 258,903 227,577 182,796 Depreciation and amortization 151,139 112,976 79,355 Capital expenditures 86,843 73,425 36,616 Manufacturing Revenue $ 465,142 $ 429,560 $ 383,964 Operating income 145,420 136,212 123,898 Depreciation and amortization 23,584 22,529 22,893 Capital expenditures 23,617 23,323 15,188
Reconciliation of Segment Operating Income and Capital Expenditures to Respective Consolidated Amounts	The following tables present reconciliations of segment operating income, depreciation and amortization, and capital expenditures to the respective consolidated amounts: Operating Income Depreciation and Amortization 2019 2018 2017 2019 2018 2017 (in thousands) Total reportable segments $ 538,235 $ 500,257 $ 421,282 $ 193,920 $ 154,974 $ 121,875 Unallocated corporate (187,084 ) (168,874 ) (133,000 ) 4,175 6,805 9,284 Total consolidated $ 351,151 $ 331,383 $ 288,282 $ 198,095 $ 161,779 $ 131,159 Capital Expenditures 2019 2018 2017 (in thousands) Total reportable segments $ 137,449 $ 131,920 $ 72,683 Unallocated corporate 3,065 8,134 9,748 Total consolidated $ 140,514 $ 140,054 $ 82,431
Revenue for Each Significant Product or Service Offering	The following tables disaggregate the Company’s revenue by major business line and timing of transfer of products or services: Major Products/Service Lines: 2019 2018 (in thousands) RMS $ 537,089 $ 519,682 DSA 1,618,995 1,316,854 Manufacturing 465,142 429,560 Total revenue $ 2,621,226 $ 2,266,096 Timing of Revenue Recognition: 2019 2018 (in thousands) RMS Services and products transferred over time $ 227,872 $ 202,872 Services and products transferred at a point in time 309,217 316,810 DSA Services and products transferred over time 1,618,281 1,316,005 Services and products transferred at a point in time 714 849 Manufacturing Services and products transferred over time 142,896 128,287 Services and products transferred at a point in time 322,246 301,273 Total revenue $ 2,621,226 $ 2,266,096 Revenue for each significant product or service offering is as follows : 2019 2018 2017 (in thousands) RMS $ 537,089 $ 519,682 $ 493,615 DSA 1,618,995 1,316,854 980,022 Manufacturing 465,142 429,560 383,964 Total revenue $ 2,621,226 $ 2,266,096 $ 1,857,601
Summary of Unallocated Corporate Overhead	A summary of unallocated corporate expense consists of the following : 2019 2018 2017 (in thousands) Stock-based compensation $ 37,855 $ 32,068 $ 27,114 Compensation, benefits, and other employee-related expenses 73,893 69,191 46,920 External consulting and other service expenses 16,639 18,652 22,224 Information technology 16,080 12,463 11,997 Depreciation 4,175 6,805 9,284 Acquisition and integration 26,877 16,295 3,728 Other general unallocated corporate 11,565 13,400 11,733 Total unallocated corporate expense $ 187,084 $ 168,874 $ 133,000
Revenue and Long-Lived Assets by Geographic Area	Revenue and long-lived assets by geographic area are as follows: U.S. Europe Canada Asia Pacific Other Consolidated (in thousands) 2019 Revenue $ 1,471,097 $ 726,421 $ 271,987 $ 146,218 $ 5,503 $ 2,621,226 Long-lived assets 602,654 253,665 127,495 60,213 101 1,044,128 2018 Revenue $ 1,267,620 $ 643,957 $ 206,382 $ 142,495 $ 5,642 $ 2,266,096 Long-lived assets 597,223 205,185 74,051 56,262 156 932,877 2017 Revenue $ 959,263 $ 569,812 $ 200,343 $ 126,462 $ 1,721 $ 1,857,601 Long-lived assets 446,574 203,911 82,228 49,020 240 781,973

SUPPLEMENTAL BALANCE SHEET IN_2

SUPPLEMENTAL BALANCE SHEET INFORMATION (Tables)	12 Months Ended
	Dec. 28, 2019
Supplemental Balance Sheet Information [Abstract]
Composition of Trade Receivables, Net	The composition of trade receivables, net is as follows: December 28, 2019 December 29, 2018 (in thousands) Client receivables $ 395,740 $ 370,131 Unbilled revenue 121,957 105,216 Total 517,697 475,347 Less: Allowance for doubtful accounts (3,664 ) (3,099 ) Trade receivables, net $ 514,033 $ 472,248
Composition of Inventories	The composition of inventories is as follows: December 28, 2019 December 29, 2018 (in thousands) Raw materials and supplies $ 24,613 $ 22,378 Work in process 35,852 21,732 Finished products 100,195 83,782 Inventories $ 160,660 $ 127,892
Composition of Other Current Assets	The composition of other current assets is as follows: December 28, 2019 December 29, 2018 (in thousands) Prepaid income tax $ 54,358 $ 47,157 Short-term investments 941 885 Restricted cash 431 465 Other 300 300 Other current assets $ 56,030 $ 48,807
Composition of Property, Plant and Equipment, Net	The composition of property, plant and equipment, net is as follows: December 28, 2019 December 29, 2018 (in thousands) Land $ 63,077 $ 52,266 Buildings (1) 1,006,357 938,184 Machinery and equipment (1) 585,965 501,894 Leasehold improvements 84,630 59,854 Furniture and fixtures 28,304 26,700 Computer hardware and software (1) 179,865 166,398 Vehicles (1) 5,561 5,167 Construction in progress 67,939 56,549 Total 2,021,698 1,807,012 Less: Accumulated depreciation (977,570 ) (874,135 ) Property, plant and equipment, net $ 1,044,128 $ 932,877 (1) These balances include assets under finance leases. See Note 16, “Leases.”
Composition of Other Assets	The composition of other assets is as follows: December 28, 2019 December 29, 2018 (in thousands) Venture capital investments $ 108,983 $ 87,545 Other investments 13,996 1,046 Life insurance policies 38,207 32,340 Restricted cash 1,601 1,411 Other 49,828 21,417 Other assets $ 212,615 $ 143,759
Composition of Other Current Liabilities	The composition of other current liabilities is as follows: December 28, 2019 December 29, 2018 (in thousands) Current portion of operating lease right-of-use liabilities $ 20,357 $ — Accrued income taxes 26,066 24,120 Customer contract deposits 33,080 38,245 Other 11,095 8,915 Other current liabilities $ 90,598 $ 71,280
Schedule of Other Long-Term Liabilities	The composition of other long-term liabilities is as follows: December 28, 2019 December 29, 2018 (in thousands) U.S. Transition Tax $ 52,066 $ 52,064 Long-term pension liability 43,054 24,671 Accrued executive supplemental life insurance retirement plan and deferred compensation plan 37,779 36,086 Long-term deferred revenue 20,983 34,420 Other 29,051 31,880 Other long-term liabilities $ 182,933 $ 179,121

FAIR VALUE (Tables)

FAIR VALUE (Tables)	12 Months Ended
	Dec. 28, 2019
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis	Assets and liabilities measured at fair value on a recurring basis are summarized below: December 28, 2019 Level 1 Level 2 Level 3 Total (in thousands) Cash equivalents $ — $ 55,278 $ — $ 55,278 Other assets: Life insurance policies — 30,454 — 30,454 Total assets measured at fair value $ — $ 85,732 $ — $ 85,732 Other current liabilities measured at fair value: Contingent consideration $ — $ — $ 712 $ 712 Foreign currency forward contract — 876 — 876 Total liabilities measured at fair value $ — $ 876 $ 712 $ 1,588 December 29, 2018 Level 1 Level 2 Level 3 Total (in thousands) Cash equivalents $ — $ 45,982 $ — $ 45,982 Other assets: Life insurance policies — 24,541 — 24,541 Total assets measured at fair value $ — $ 70,523 $ — $ 70,523 Other current liabilities: Contingent consideration $ — $ — $ 3,033 $ 3,033 Foreign currency forward contract — 1,319 — 1,319 Total liabilities measured at fair value $ — $ 1,319 $ 3,033 $ 4,352
Rollforward of Contingent Consideration	The following table provides a rollforward of the contingent consideration related to previous business acquisitions. See Note 2, “Business Combinations and Divestiture”. Fiscal Year 2019 2018 (in thousands) Beginning balance $ 3,033 $ 298 Additions 2,869 3,315 Payments (5,252 ) — Total gains or losses (realized/unrealized): Foreign currency translation 62 (298 ) Reversal of previously recorded contingent liability and change in fair value — (282 ) Ending balance $ 712 $ 3,033
Schedule of Book and Fair Values of Debt	The book value and fair value of the Company’s 2026 and 2028 Senior Notes is summarized below: December 28, 2019 December 29, 2018 Book Value Fair Value Book Value Fair Value 2026 Senior Notes $ 500,000 $ 537,500 $ 500,000 $ 495,000 2028 Senior Notes 500,000 510,000 — —

GOODWILL AND INTANGIBLE ASSETS

GOODWILL AND INTANGIBLE ASSETS (Tables)	12 Months Ended
	Dec. 28, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Rollforward of Goodwill	The following table provides a rollforward of the Company’s goodwill: Adjustments to Goodwill Adjustments to Goodwill December 30, 2017 Acquisitions Foreign Exchange December 29, 2018 Acquisitions Foreign Exchange December 28, 2019 (in thousands) RMS $ 58,122 $ — $ (1,154 ) $ 56,968 $ — $ (382 ) $ 56,586 DSA 1,610,176 460,223 (13,929 ) 2,056,470 293,380 373 2,350,223 Manufacturing 141,608 2,551 (5,464 ) 138,695 — 61 138,756 Gross carrying amount 1,809,906 462,774 (20,547 ) 2,252,133 293,380 52 2,545,565 Accumulated impairment loss - DSA (1,005,000 ) — — (1,005,000 ) — — (1,005,000 ) Goodwill $ 804,906 $ 1,247,133 $ 1,540,565
Schedule of Intangible Assets, Net by Class	The following table displays intangible assets, net by major class: December 28, 2019 December 29, 2018 Gross Accumulated Net Gross Accumulated Net (in thousands) Backlog $ 28,865 $ (26,895 ) $ 1,970 $ 20,900 $ (18,691 ) $ 2,209 Technology 122,106 (57,737 ) 64,369 101,506 (41,870 ) 59,636 Trademarks and trade names 8,430 (4,901 ) 3,529 8,331 (4,640 ) 3,691 Other 18,279 (12,307 ) 5,972 17,448 (10,041 ) 7,407 Other intangible assets 177,680 (101,840 ) 75,840 148,185 (75,242 ) 72,943 Client relationships 934,668 (321,095 ) 613,573 791,725 (253,780 ) 537,945 Intangible assets $ 1,112,348 $ (422,935 ) $ 689,413 $ 939,910 $ (329,022 ) $ 610,888
Schedule of Estimated Amortization Expense	As of December 28, 2019 , 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) 2020 $ 97,024 2021 87,540 2022 76,204 2023 67,807 2024 60,918

LONG-TERM DEBT AND FINANCE LE_2

LONG-TERM DEBT AND FINANCE LEASE OBLIGATIONS (Tables)	12 Months Ended
	Dec. 28, 2019
Debt Disclosure [Abstract]
Schedule of Long-term Debt, Net	Long-term debt, net and finance leases consists of the following: December 28, 2019 December 29, 2018 (in thousands) Term loans $ 193,750 $ 731,250 Revolving facility 676,134 397,452 2026 Senior Notes 500,000 500,000 2028 Senior Notes 500,000 — Other debt 5,781 26,286 Finance leases (Note 16) 30,527 29,240 Total debt and finance leases 1,906,192 1,684,228 Less: Current portion of long-term debt 35,548 28,228 Current portion of finance leases (Note 16) 2,997 3,188 Current portion of long-term debt and finance leases 38,545 31,416 Long-term debt and finance leases 1,867,647 1,652,812 Debt discount and debt issuance costs (17,981 ) (16,214 ) Long-term debt, net and finance leases $ 1,849,666 $ 1,636,598
Schedule of Principal Maturities of Existing Debt	Principal maturities of existing debt for the periods set forth in the table below, are as follows: Principal (in thousands) 2020 $ 35,536 2021 61,151 2022 93,966 2023 682,602 2024 468 Thereafter 1,001,942 Total $ 1,875,665

EQUITY AND NONCONTROLLING INT_2

EQUITY AND NONCONTROLLING INTERESTS (Tables)	12 Months Ended
	Dec. 28, 2019
Equity [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 2019 2018 2017 (in thousands) Numerator: Income from continuing operations, net of income taxes $ 254,061 $ 227,218 $ 125,586 Income (loss) from discontinued operations, net of income taxes — 1,506 (137 ) Less: Net income attributable to noncontrolling interests 2,042 2,351 2,094 Net income attributable to common shareholders $ 252,019 $ 226,373 $ 123,355 Denominator: Weighted-average shares outstanding— Basic 48,730 47,947 47,481 Effect of dilutive securities: Stock options, restricted stock, restricted stock units and performance share units 963 1,071 1,083 Weighted-average shares outstanding—Diluted 49,693 49,018 48,564
Changes to Each Component of Accumulated Other Comprehensive Income (Loss), Net of Income Taxes	Changes to each component of accumulated other comprehensive income (loss), net of income taxes, are as follows: Foreign Currency Translation Adjustment and Other Pension and Other Post-Retirement Benefit Plans Total (in thousands) December 30, 2017 $ (77,545 ) $ (67,186 ) $ (144,731 ) Other comprehensive loss before reclassifications (1) (27,352 ) (1,659 ) (29,011 ) Amounts reclassified from accumulated other comprehensive income (loss) — 2,477 2,477 Net current period other comprehensive (loss) income (27,352 ) 818 (26,534 ) Amount reclassified from accumulated other comprehensive loss due to the adoption of ASU 2018-02 — 3,330 3,330 Income tax (benefit) expense (2,698 ) 806 (1,892 ) December 29, 2018 (102,199 ) (70,504 ) (172,703 ) Other comprehensive income (loss) before reclassifications (1) 14,444 (25,165 ) (10,721 ) Amounts reclassified from accumulated other comprehensive income (loss) — 1,772 1,772 Net current period other comprehensive income (loss) 14,444 (23,393 ) (8,949 ) Income tax (benefit) (177 ) (3,456 ) (3,633 ) December 28, 2019 $ (87,578 ) $ (90,441 ) $ (178,019 ) (1) The impact of the foreign currency translation adjustment to other comprehensive income (loss) before reclassifications was primarily due to the effect of changes in foreign currency exchange rates of the Euro, British Pound, and Canadian Dollar and to a lesser extent due to the impact of changes in the Chinese Yuan Renminbi and Japanese Yen.
Rollforward of Redeemable Noncontrolling Interest	The following table provides a rollforward of the activity related to the Company’s redeemable noncontrolling interests: Fiscal Year 2019 2018 (in thousands) Beginning balance $ 18,525 $ 16,609 Adjustment to Vital River redemption value 1,451 2,069 Purchase of Vital River 5% equity interest (8,745 ) — Change in fair value of Vital River 8% equity interest, included in additional paid-in capital 2,708 — Modification of Vital River 8% purchase option 2,196 — Acquisition of an approximate 10% non-controlling interest through acquiring Citoxlab 4,035 — Acquisition of a 20% non-controlling interest through acquiring a supplier 8,740 — Net (loss) income attributable to noncontrolling interests (42 ) 800 Foreign currency translation (221 ) (953 ) Ending balance $ 28,647 $ 18,525

INCOME TAXES (Tables)

INCOME TAXES (Tables)	12 Months Ended
	Dec. 28, 2019
Income Tax Disclosure [Abstract]
Components of Income 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 2019 2018 2017 (in thousands) Income from continuing operations before income taxes: U.S. $ 108,326 $ 95,062 $ 123,896 Non-U.S. 195,758 186,619 173,059 $ 304,084 $ 281,681 $ 296,955 Income tax provision (benefit): Current: Federal $ 18,101 $ 17,390 $ 93,871 Foreign 43,489 38,557 37,150 State 9,915 8,837 12,361 Total current 71,505 64,784 143,382 Deferred: Federal (3,226 ) (7,145 ) 9,416 Foreign (17,111 ) (4,104 ) 14,953 State (1,145 ) 928 3,618 Total deferred (21,482 ) (10,321 ) 27,987 $ 50,023 $ 54,463 $ 171,369
Reconciliations of the 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 2019 2018 2017 U.S. statutory income tax rate 21.0 % 21.0 % 35.0 % Foreign tax rate differences 2.7 0.5 (6.8 ) State income taxes, net of federal tax benefit 2.6 2.4 2.0 Non-deductible compensation 1.7 1.0 1.3 Research tax credits and enhanced deductions (4.4 ) (2.9 ) (2.4 ) Stock-based compensation (2.2 ) (2.1 ) (3.2 ) Enacted tax rate changes (0.7 ) (0.1 ) (4.2 ) Transition Tax — (0.3 ) 24.8 Impact of tax uncertainties (2.6 ) (1.1 ) (0.4 ) Tax on unremitted earnings 1.7 1.2 7.3 Impact of acquisitions and restructuring 2.7 0.3 3.8 Net operating loss deferred tax asset recognition, net of valuation allowance (NOL DTA) (6.8 ) — — Other 0.8 (0.6 ) 0.5 Effective income tax rate 16.5 % 19.3 % 57.7 %
Components of Deferred Tax Assets and Liabilities	The components of deferred tax assets and liabilities are as follows: December 28, 2019 December 29, 2018 (in thousands) Deferred tax assets: Compensation $ 40,582 $ 36,724 Accruals and reserves 13,687 13,183 Net operating loss and credit carryforwards 367,269 35,679 Operating lease liability 33,785 — Other 7,181 5,060 Valuation allowance (309,962 ) (9,788 ) Total deferred tax assets 152,542 80,858 Deferred tax liabilities: Goodwill and other intangibles (174,847 ) (154,743 ) Depreciation related (29,317 ) (19,373 ) Venture capital investments (12,806 ) (10,557 ) Tax on unremitted earnings (17,282 ) (14,140 ) Right-of-use assets (34,953 ) — Other (5,961 ) (2,296 ) Total deferred tax liabilities (275,166 ) (201,109 ) Net deferred taxes $ (122,624 ) $ (120,251 )
Reconciliation of the Company's Beginning and Ending Unrecognized Income Tax Benefits	A reconciliation of the Company’s beginning and ending unrecognized income tax benefits is as follows: Fiscal Year 2019 2018 2017 (in thousands) Beginning balance $ 18,827 $ 24,710 $ 24,186 Additions to tax positions for current year 3,691 2,477 1,791 Additions to tax positions for prior years 5,234 — 1,428 Reductions to tax positions for prior years (1,033 ) (4,543 ) — Settlements (274 ) (3,380 ) (1,754 ) Expiration of statute of limitations (6,780 ) (437 ) (941 ) Ending balance $ 19,665 $ 18,827 $ 24,710

EMPLOYEE BENEFIT PLANS (Tables)

EMPLOYEE BENEFIT PLANS (Tables)	12 Months Ended
	Dec. 28, 2019
Retirement Benefits [Abstract]
Reconciliation of Benefit Obligations and Plans Assets of the Company's Pension Plans	The following table provides a reconciliation of benefit obligations and plan assets of the Company’s pension, DCP and ESLIRP plans: December 28, 2019 December 29, 2018 (in thousands) Change in projected benefit obligations: Benefit obligation at beginning of year $ 362,805 $ 392,964 Service cost 2,833 2,612 Interest cost 11,583 10,850 Other 850 1,499 Benefit payments (11,062 ) (8,886 ) Settlements (74 ) — Special/Contractual Termination Benefits 166 — Plan amendments — 104 Transfer in from acquisition 6,818 — Actuarial loss (gain) 66,432 (21,168 ) Administrative expenses paid (470 ) (195 ) Effect of foreign exchange 7,528 (14,975 ) Benefit obligation at end of year $ 447,409 $ 362,805 Change in fair value of plan assets: Fair value of plan assets at beginning of year $ 305,709 $ 304,325 Actual return on plan assets 53,741 (7,419 ) Employer contributions 2,105 31,174 Settlements (74 ) — Transfer in from acquisition 119 — Benefit payments (11,062 ) (8,886 ) Administrative expenses paid (470 ) (195 ) Effect of foreign exchange 7,113 (13,290 ) Fair value of plan assets at end of year $ 357,181 $ 305,709 Net balance sheet liability $ 90,228 $ 57,096 Amounts recognized in balance sheet: Noncurrent assets $ 1,742 $ 3,280 Current liabilities 12,788 1,095 Noncurrent liabilities 79,182 59,281
Amounts Recognized in Accumulated Other Comprehensive Loss Related to the Company's Pensions Plans	Amounts recognized in accumulated other comprehensive loss related to the Company’s pension, DCP and ESLIRP plans are as follows: Fiscal Year 2019 2018 (in thousands) Net actuarial loss $ 116,930 $ 93,483 Net prior service cost (credit) (2,096 ) (2,585 ) Net amount recognized $ 114,834 $ 90,898
Accumulated Benefit Obligation and Fair of Plan Assets	The accumulated benefit obligation and fair value of plan assets for the Company’s pension, DCP and ESLIRP plans with accumulated benefit obligations in excess of plan assets are as follows: December 28, 2019 December 29, 2018 (in thousands) Accumulated benefit obligation $ 410,243 $ 254,138 Fair value of plan assets 337,344 207,538
Projected Benefit Obligation and Fair Value of Plan Assets	The projected benefit obligation and fair value of plan assets for the Company’s pension, DCP and ESLIRP plans with projected benefit obligations in excess of plan assets are as follows: December 28, 2019 December 29, 2018 (in thousands) Projected benefit obligation $ 435,638 $ 273,625 Fair value of plan assets 343,688 213,249
Amounts in Accumulated Other Comprehensive Income 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: December 28, 2019 (in thousands) Amortization of net actuarial loss $ 6,344 Amortization of net prior service credit (501 )
Components of Net Periodic Benefit Costs for the Company's Pension Plans	Components of net periodic benefit cost for the Company’s pension, DCP and ESLIRP plans are as follows: Fiscal Year 2019 2018 2017 (in thousands) Service cost $ 2,833 $ 2,612 $ 3,110 Interest cost 11,583 10,850 11,642 Expected return on plan assets (13,005 ) (15,516 ) (14,249 ) Amortization of prior service credit (489 ) (514 ) (496 ) Amortization of net loss 2,250 2,990 3,845 Other 850 910 — Net periodic cost (benefit) $ 4,022 $ 1,332 $ 3,852
Weighted-average Assumptions	Weighted-average assumptions used to determine projected benefit obligations are as follows: December 28, 2019 December 29, 2018 Discount rate 2.14 % 3.21 % Rate of compensation increase 2.99 % 3.23 % 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. Specifically for the expected termination of the U.S. Pension Plan, estimated costs of lump sum payments and annuity purchases are reflected in the discount rate. A 25 basis point change across all discount rates changes the projected benefit obligation by approximately $20 million for all Company plans. Weighted-average assumptions used to determine net periodic benefit cost are as follows: December 28, 2019 December 29, 2018 December 30, 2017 Discount rate 3.21 % 2.82 % 3.01 % Expected long-term return on plan assets 4.28 % 5.18 % 5.41 % Rate of compensation increase 3.23 % 3.16 % 3.25 %
Fair Value of the Company's Pension Plan Assets by Asset Category	The fair value of the Company’s pension plan assets by asset category are as follows: December 28, 2019 December 29, 2018 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total (in thousands) Cash and cash equivalents $ 2,388 $ 1,022 $ — $ 3,410 $ 7,317 $ — $ — $ 7,317 Equity securities (1) 7,621 84,377 — 91,998 72,237 — — 72,237 Debt securities (2) 40,281 89,684 — 129,965 17,147 4,100 — 21,247 Mutual funds (3) 6,324 68,632 — 74,956 86,282 59,984 — 146,266 Other (4) 551 54,787 1,514 56,852 718 56,283 1,641 58,642 Total $ 57,165 $ 298,502 $ 1,514 $ 357,181 $ 183,701 $ 120,367 $ 1,641 $ 305,709 (1) This category comprises equity investments and 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. (2) This category comprises debt investments and securities held by U.S. and non-U.S. pension plans valued at the quoted closing price. For non-U.S. pension plans, the quoted closing price is translated into U.S. dollars using a foreign currency exchange rate at year end. Holdings primarily include investment-grade corporate bonds and U.S. treasuries at various durations. (3) This category comprises non-U.S. mutual funds valued at the net asset value of shares held at year end and translated into U.S. dollars using a foreign currency exchange rate at year end. (4) This category mainly comprises fixed income securities tied to various U.K. government bond yields held by non-US pension plans valued at the net asset value of shares held at year-end, and translated into U.S. dollars using a foreign currency exchange rate at year end.
Estimated Future Benefit Payments Over the Next Five Years	to participants in connection with the U.S. Pension Plan termination and $8 million to an executive officer expected to retire: Fiscal Year Pension Plans (in thousands) 2020 $ 111,848 2021 9,420 2022 10,344 2023 40,911 2024 10,814 2025-2029 59,646

STOCK-BASED COMPENSATION (Table

STOCK-BASED COMPENSATION (Tables)	12 Months Ended
	Dec. 28, 2019
Share-based Payment Arrangement [Abstract]
Financial Statement Line Items in Which Stock-based Compensation is Reflected	The following table provides stock-based compensation by the financial statement line item in which it is reflected: Fiscal Year 2019 2018 2017 (in thousands) Cost of revenue $ 9,038 $ 6,285 $ 6,509 Selling, general and administrative 48,233 41,061 37,494 Stock-based compensation, before income taxes 57,271 47,346 44,003 Provision for income taxes (9,465 ) (9,188 ) (13,428 ) Stock-based compensation, net of income taxes $ 47,806 $ 38,158 $ 30,575
Summary of Stock Option Activity	The following table summarizes stock option activity under the Company’s stock-based compensation plans: Number of shares Weighted Average Weighted Average Aggregate (in thousands) (in years) (in thousands) Options outstanding as of December 29, 2018 1,556 $ 86.44 Options granted 454 $ 144.42 Options exercised (442 ) $ 78.49 Options canceled (61 ) $ 113.17 Options outstanding as of December 28, 2019 1,507 $ 105.19 2.7 $ 70,459 Options exercisable as of December 28, 2019 390 $ 77.87 1.5 $ 28,897 Options expected to vest as of December 28, 2019 1,117 $ 114.73 3.1 $ 41,562
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 2019 2018 2017 Expected life (in years) 3.6 3.7 3.6 Expected volatility 27 % 25 % 24 % Risk-free interest rate 2.4 % 2.4 % 1.6 % Expected dividend yield 0 % 0 % 0 %
Summary of Restricted Stock and Restricted Stock Unit Activity	The following table summarizes the restricted stock units activity for fiscal year 2019 : Restricted Stock Units Weighted (in thousands) December 29, 2018 490 $ 93.80 Granted 221 $ 142.85 Vested (185 ) $ 89.34 Canceled (30 ) $ 115.10 December 28, 2019 496 $ 116.07
Information about PSUs and Related 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 2019 2018 2017 (shares in thousands) PSUs granted 160 200 198 Weighted average grant date fair value $ 164.47 $ 117.89 $ 99.96 Key Assumptions: Expected volatility 25 % 26 % 26 % Risk-free interest rate 2.4 % 2.4 % 1.3 % Expected dividend yield 0 % 0 % 0 % Total shareholder return of 20-trading day average stock price on grant date 17.7 % 2.9 % 17.7 %

FOREIGN CURRENCY CONTRACTS (Tab

FOREIGN CURRENCY CONTRACTS (Tables)	12 Months Ended
	Dec. 28, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Notional and Fair Value of Foreign Currency Contracts	The notional amount and fair value of the open contract is summarized as follows: December 28, 2019 Notional Amount Fair Value Balance Sheet Location (in thousands) $ 115,038 $ (876 ) Other current liabilities The notional amount and fair value of the open contract is summarized as follows: December 29, 2018 Notional Amount Fair Value Balance Sheet Location (in thousands) $ 343,300 $ (1,319 ) Other current liabilities
Schedule of Derivative Instruments on Statements of Income	The following table summarizes the effect of the foreign exchange forward contracts in connection with certain intercompany loans on the Company’s consolidated statements of income: Fiscal Year 2019 Location of gain (loss) Financial statement caption amount Amount of gain (loss) (in thousands) Other income, net $ 12,293 $ (121 ) The following table summarizes the effect of the foreign exchange forward contracts entered into to limit the Company’s foreign currency exposure related to U.S. dollar denominated loans borrowed by a non-U.S. Euro functional currency entity under the Credit Facility on the Company’s consolidated statements of income: Fiscal Year 2019 2018 Location of gain (loss) Financial statement caption amount Amount of gain (loss) Financial statement caption amount Amount of gain (loss) (in thousands) Interest expense $ 60,882 $ 18,672 $ 63,772 1,486

RESTRUCTURING AND ASSET IMPAI_2

RESTRUCTURING AND ASSET IMPAIRMENTS (Tables)	12 Months Ended
	Dec. 28, 2019
Restructuring and Related Activities [Abstract]
Schedule of Restructuring Costs	The following table presents a summary of restructuring costs related to these initiatives by classification within the consolidated statements of income: Severance and Transition Costs Asset Impairments and Other Costs Total (in thousands) December 28, 2019 Cost of services provided and products sold (excluding amortization of intangible assets) $ 4,348 $ 2,367 $ 6,715 Selling, general and administrative 7,106 18 7,124 Total $ 11,454 $ 2,385 $ 13,839 December 29, 2018 Cost of services provided and products sold (excluding amortization of intangible assets) $ 923 $ 27 $ 950 Selling, general and administrative 6,597 21 6,618 Total $ 7,520 $ 48 $ 7,568 December 30, 2017 Cost of services provided and products sold (excluding amortization of intangible assets) $ 1,944 $ 929 $ 2,873 Selling, general and administrative 1,905 — 1,905 Total $ 3,849 $ 929 $ 4,778 The following table presents restructuring costs by reportable segment for these productivity improvement initiatives: Fiscal Year 2019 2018 2017 (in thousands) RMS $ 3,110 $ — $ 291 DSA 7,307 1,063 1,604 Manufacturing 3,032 1,227 2,883 Unallocated corporate 390 5,278 — Total $ 13,839 $ 7,568 $ 4,778 The following table presents a summary of severance and transition costs, and asset impairments (referred to as restructuring costs) related to this initiative during fiscal years 2018 and 2017 by classification within the consolidated statements of income. The Company did not incur any restructuring costs during fiscal year December 28, 2019 . Severance and Transition Costs Asset Impairments and Other Costs Total (in thousands) December 29, 2018 Cost of services provided and products sold (excluding amortization of intangible assets) $ 847 $ 822 $ 1,669 Selling, general and administrative 314 — 314 Total $ 1,161 $ 822 $ 1,983 December 30, 2017 Cost of services provided and products sold (excluding amortization of intangible assets) $ 362 $ 17,716 $ 18,078 Selling, general and administrative 67 — 67 Total $ 429 $ 17,716 $ 18,145
Rollforward of Company's Severance and Retention Costs Liability	The following table provides a rollforward for all of the Company’s severance and transition costs, and certain lease obligation liabilities related to restructuring activities: Fiscal Year 2019 2018 2017 (in thousands) Beginning balance $ 2,921 $ 6,856 $ 8,102 Expense (excluding non-cash charges) 12,674 8,681 4,278 Payments / utilization (9,206 ) (12,341 ) (6,103 ) Foreign currency adjustments 17 (275 ) 579 Ending balance $ 6,406 $ 2,921 $ 6,856

LEASES (Tables)

LEASES (Tables)	12 Months Ended
	Dec. 28, 2019
Leases [Abstract]
Schedule of Cumulative Effect of Adoption of ASC 842	The cumulative effect of applying ASC 842 to all leases that had commenced as of December 29, 2018 was as follows: Balance sheet captions impacted by ASC 842 December 30, 2018 (Prior to adoption of ASC 842) Effect of the adoption of ASC 842 December 30, 2018 (As adjusted) (in thousands) Prepaid assets $ 53,447 $ (4,413 ) (1) $ 49,034 Property, plant and equipment, net 932,877 (23,448 ) (2) 909,429 Operating lease right-of-use assets, net — 134,172 (3) 134,172 Other assets 143,759 (4,989 ) (4) 138,770 Other current liabilities 71,280 15,935 (5) 87,215 Operating lease right-of-use liabilities — 111,570 (6) 111,570 Long-term debt, net and finance leases 1,636,598 (26,183 ) (7) 1,610,415 ASC 842 adoption adjustments: (1) Short term prepaid rent reclassified from Prepaid assets to the Operating lease right-of-use assets, net. (2) Derecognition of approximately $26 million of leased properties, recorded in Property, plant and equipment, net, specifically Construction-in-process, that were recognized under the previously existing build-to-suit accounting (3) Recognition of Operating lease right-of-use assets, net, and adjusted for prepaid rent and deferred rent liability reclassification adjustments identified in adjustments (1) (4) (5) . (4) Long-term prepaid rent reclassified from Other assets to Operating lease right-of-use assets, net. (5) Recognition of short-term portion of the Operating lease right-of-use liabilities offset by reclassification of deferred rent liability to Operating lease right-of-use assets, net. (6) Recognition of long-term portion of the Operating lease right-of-use liabilities. (7) Derecognition of approximately $26 million of Other debt associated with leased properties that were recognized under the previously existing build-to-suit accounting rules.
Schedule of Right-of-Use Lease Assets and Lease Liabilities in Condensed Financial Statements	Right-of-use lease assets and lease liabilities are reported in the Company’s consolidated balance sheets as follows: December 28, 2019 (in thousands) Operating leases Operating lease right-of-use assets, net $ 140,085 Other current liabilities $ 20,357 Operating lease right-of-use liabilities 116,252 Total operating lease liabilities $ 136,609 Finance leases Property, plant and equipment, net $ 32,519 Current portion of long-term debt and finance leases $ 2,997 Long-term debt, net and finance leases 27,530 Total finance lease liabilities $ 30,527
Schedule of Operating and Finance Lease Costs and Supplemental Cash Flow Information	The components of operating and finance lease costs for fiscal year 2019 were as follows: Fiscal Year December 28, 2019 (in thousands) Operating lease costs $ 30,885 Finance lease costs: Amortization of right-of-use assets 4,007 Interest on lease liabilities 1,349 Short-term lease costs 1,056 Variable lease costs 3,161 Sublease income (994 ) Total lease costs $ 39,464 Other information related to leases was as follows: Supplemental cash flow information Fiscal Year December 28, 2019 (in thousands) Cash flows included in the measurement of lease liabilities: Operating cash flows from operating leases $ 27,153 Operating cash flows from finance leases 1,406 Finance cash flows from finance leases 3,766 Non-cash leases activity: Right-of-use lease assets obtained in exchange for new operating lease liabilities $ 24,382 Right-of-use lease assets obtained in exchange for new finance lease liabilities 4,819 Lease term and discount rate As of December 28, 2019 Weighted-average remaining lease term (in years) Operating lease 8.23 Finance lease 12.97 Weighted-average discount rate Operating lease 4.36 Finance lease 4.58
Schedule of Future Minimum Lease Payments Under Non-Cancellable Operating Leases After Adoption	As of December 28, 2019 , maturities of operating and finance lease liabilities for each of the following five years and a total thereafter were as follows: Operating Leases Finance Leases (in thousands) 2020 $ 25,955 $ 4,308 2021 25,028 3,832 2022 20,614 3,819 2023 16,853 2,929 2024 16,007 2,141 Thereafter 60,371 23,650 Total minimum future lease payments 164,828 40,679 Less: Imputed interest 28,219 10,152 Total lease liabilities $ 136,609 $ 30,527
Schedule of Future Minimum Lease Payments Under Non-Cancellable Finance Leases After Adoption	As of December 28, 2019 , maturities of operating and finance lease liabilities for each of the following five years and a total thereafter were as follows: Operating Leases Finance Leases (in thousands) 2020 $ 25,955 $ 4,308 2021 25,028 3,832 2022 20,614 3,819 2023 16,853 2,929 2024 16,007 2,141 Thereafter 60,371 23,650 Total minimum future lease payments 164,828 40,679 Less: Imputed interest 28,219 10,152 Total lease liabilities $ 136,609 $ 30,527
Schedule of Future Minimum Lease Payments, Non-Cancellable Operating Leases Before Adoption	As of December 29, 2018 , minimum future lease payments under non-cancellable leases for each of the following five years and a total thereafter were as follows: Operating Leases (1) Finance Leases (1) (in thousands) 2019 $ 25,411 $ 3,972 2020 22,400 3,759 2021 21,544 2,869 2022 18,535 2,967 2023 15,398 2,209 Thereafter 66,870 24,304 Total minimum future lease payments $ 170,158 $ 40,080 (1) Lease commitments are presented under the guidance of ASC 840 and includes approximately $14 million of minimum future lease payments for leases that had not commenced as of December 29, 2018. These commitments relate to existing leases for which the Company does not yet control certain expansion space.
Schedule of Future Minimum Lease Payments, Non-Cancellable Capital Leases Before Adoption	As of December 29, 2018 , minimum future lease payments under non-cancellable leases for each of the following five years and a total thereafter were as follows: Operating Leases (1) Finance Leases (1) (in thousands) 2019 $ 25,411 $ 3,972 2020 22,400 3,759 2021 21,544 2,869 2022 18,535 2,967 2023 15,398 2,209 Thereafter 66,870 24,304 Total minimum future lease payments $ 170,158 $ 40,080 (1) Lease commitments are presented under the guidance of ASC 840 and includes approximately $14 million of minimum future lease payments for leases that had not commenced as of December 29, 2018. These commitments relate to existing leases for which the Company does not yet control certain expansion space.

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Tables)	12 Months Ended
	Dec. 28, 2019
Commitments and Contingencies Disclosure [Abstract]
Schedule of Unconditional Purchase Obligations	The aggregate amount of the Company’s unconditional purchase obligations totaled $154.0 million as of December 28, 2019 and is expected to be paid as follows: Payments Due by Period Less than 1 - 3 Years 3 - 5 Years Total (in millions) Unconditional purchase obligations $ 106.1 $ 45.0 $ 2.9 $ 154.0

SELECTED QUARTERLY FINANCIAL _2

SELECTED QUARTERLY FINANCIAL DATA (unaudited) (Tables)	12 Months Ended
	Dec. 28, 2019
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Data	The following table contains quarterly financial information for fiscal years 2019 and 2018 . The operating results for any quarter are not necessarily indicative of future period results. First Quarter Second Quarter Third Quarter Fourth Quarter (in thousands, except per share amounts) Fiscal Year 2019 Total revenue $ 604,569 $ 657,568 $ 667,951 $ 691,138 Gross profit (1) 211,777 238,104 246,116 262,314 Operating income 69,792 79,768 92,802 108,789 Net income attributable to common shareholders 55,133 43,728 72,810 80,348 Earnings per common share Basic: Continuing operations attributable to common shareholders $ 1.14 $ 0.90 $ 1.49 $ 1.64 Discontinued operations $ — $ — $ — $ — Net income attributable to common shareholders $ 1.14 $ 0.90 $ 1.49 $ 1.64 Diluted: Continuing operations attributable to common shareholders $ 1.11 $ 0.88 $ 1.46 $ 1.61 Discontinued operations $ — $ — $ — $ — Net income attributable to common shareholders $ 1.11 $ 0.88 $ 1.46 $ 1.61 Fiscal Year 2018 Total revenue $ 493,970 $ 585,301 $ 585,295 $ 601,530 Gross profit (1) 181,469 215,981 216,200 226,417 Operating income 67,829 76,710 84,362 102,482 Net income attributable to common shareholders 52,631 53,709 60,368 59,665 Earnings per common share Basic: Continuing operations attributable to common shareholders $ 1.10 $ 1.08 $ 1.25 $ 1.24 Discontinued operations $ — $ 0.03 $ — $ — Net income attributable to common shareholders $ 1.10 $ 1.11 $ 1.25 $ 1.24 Diluted: Continuing operations attributable to common shareholders $ 1.08 $ 1.06 $ 1.22 $ 1.21 Discontinued operations $ — $ 0.03 $ — $ — Net income attributable to common shareholders $ 1.08 $ 1.10 $ 1.22 $ 1.21 (1) Gross profit is calculated as total revenue minus cost of revenue (excluding amortization of intangible assets).

DESCRIPTION OF BUSINESS AND S_4

DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Details) $ in Millions	Dec. 28, 2019USD ($)contract	Dec. 29, 2018USD ($)contract
Debt Instrument [Line Items]
Number of life insurance contracts | contract	44	45
Face value of life insurance contracts | $	$ 72.7	$ 65.2
Minimum
Debt Instrument [Line Items]
Company's ownership percentage	1.00%
Renewal term for leases	1 year
Maximum
Debt Instrument [Line Items]
Company's ownership percentage	12.00%
Renewal term for leases	5 years

DESCRIPTION OF BUSINESS AND S_5

DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Property, Plant and Equipment, Net (Details)	12 Months Ended
	Dec. 28, 2019
Minimum | Buildings
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	20 years
Minimum | Machinery and equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	3 years
Minimum | Furniture and fixtures
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	5 years
Minimum | Computer hardware and software
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	3 years
Minimum | Vehicles
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	3 years
Maximum | Buildings
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	40 years
Maximum | Machinery and equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	20 years
Maximum | Furniture and fixtures
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	10 years
Maximum | Computer hardware and software
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	8 years
Maximum | Vehicles
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	5 years

BUSINESS COMBINATIONS AND DIV_3

BUSINESS COMBINATIONS AND DIVESTITURE - Additional Information (Details) € in Millions, £ in Millions

Jan. 03, 2020USD ($)

Aug. 28, 2019USD ($)

Apr. 29, 2019USD ($)

Apr. 03, 2018USD ($)

Jan. 11, 2018USD ($)

Aug. 04, 2017USD ($)

Jun. 29, 2019USD ($)

Apr. 01, 2017USD ($)

Dec. 28, 2019USD ($)

Dec. 29, 2018USD ($)

Dec. 28, 2019USD ($)

Dec. 29, 2018USD ($)

Dec. 30, 2017USD ($)

Sep. 29, 2018EUR (€)

Sep. 29, 2018USD ($)

Jan. 11, 2018GBP (£)

Aug. 04, 2017EUR (€)

Aug. 04, 2017USD ($)

Feb. 10, 2017USD ($)

Business Acquisition [Line Items]

Gain on divestiture

$ 0

$ 0

$ 10,577,000

CDMO Business | Disposal Group, Disposed of by Sale, Not Discontinued Operations

Business Acquisition [Line Items]

Cash received from divestiture

$ 75,000,000

Cash and cash equivalents transferred

600,000

Working capital adjustments

$ 300,000

Gain on divestiture

$ 10,600,000

Citoxlab

Business Acquisition [Line Items]

Purchase price

$ 527,700,000

Transaction and integration costs

$ 20,700,000

Purchase price allocation

491,007,000

Cash acquired

36,700,000

Goodwill resulting from transaction

$ 7,200,000

Revenue since acquisition

123,700,000

Operating income (loss) since acquisition

$ 6,200,000

Weighted average life

12 years

Citoxlab | Client relationships

Business Acquisition [Line Items]

Weighted average life

13 years

Citoxlab | Depreciation and Amortization Expense

Business Acquisition [Line Items]

Adjustments to purchase price

5,700,000

9,400,000

Citoxlab | Interest expense

Business Acquisition [Line Items]

Adjustments to purchase price

1,200,000

4,100,000

MPI Research

Business Acquisition [Line Items]

Purchase price

$ 829,700,000

Transaction and integration costs

0

16,500,000

Purchase price allocation

800,800,000

Cash acquired

27,700,000

Goodwill resulting from transaction

4,100,000

Revenue since acquisition

$ 209,500,000

Operating income (loss) since acquisition

$ 33,400,000

Adjustments to purchase price

$ 1,200,000

Weighted average life

12 years

MPI Research | Client relationships

Business Acquisition [Line Items]

Weighted average life

13 years

MPI Research | Depreciation and Amortization Expense

Business Acquisition [Line Items]

Adjustments to purchase price

14,100,000

22,400,000

MPI Research | Interest expense

Business Acquisition [Line Items]

Adjustments to purchase price

2,800,000

27,100,000

KWS BioTest Limited

Business Acquisition [Line Items]

Purchase price

$ 20,300,000

Transaction and integration costs

$ 0

700,000

Purchase price allocation

21,529,000

Cash acquired

1,000,000

Adjustments to purchase price

$ 400,000

Contingent consideration

€ 2

$ 2,600,000

£ 3

KWS BioTest Limited | Client relationships

Business Acquisition [Line Items]

Weighted average life

12 years

Brains On-Line

Business Acquisition [Line Items]

Purchase price

$ 21,300,000

Transaction and integration costs

$ 0

$ 0

$ 2,600,000

Purchase price allocation

$ 20,122,000

Cash acquired

$ 600,000

Contingent consideration | €

€ 6.7

Weighted average life

12 years

Contingent consideration paid

$ 2,600,000

Brains On-Line | Client relationships

Business Acquisition [Line Items]

Weighted average life

13 years

Other Acquisitions

Business Acquisition [Line Items]

Purchase price

$ 23,400,000

Transaction and integration costs

$ 3,600,000

Purchase price allocation

23,063,000

Cash acquired

300,000

Amount of pre-existing relationship for supply agreement

$ 4,000,000

Supplier

Business Acquisition [Line Items]

Ownership percentage

80.00%

Remaining ownership interest

20.00%

20.00%

Supplier | Other Acquisitions

Business Acquisition [Line Items]

Ownership percentage

80.00%

Remaining ownership interest

20.00%

Subsequent Event | HemaCare Corporation

Business Acquisition [Line Items]

Purchase price

$ 380,000,000

Transaction and integration costs

$ 3,300,000

BUSINESS COMBINATIONS AND DIV_4

BUSINESS COMBINATIONS AND DIVESTITURE - Purchase Price Allocations (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Aug. 28, 2019	Apr. 29, 2019	Dec. 29, 2018	Apr. 03, 2018	Jan. 11, 2018	Dec. 30, 2017	Aug. 04, 2017
Business Acquisition [Line Items]
Goodwill	$ 1,540,565			$ 1,247,133			$ 804,906
Citoxlab
Business Acquisition [Line Items]
Acquired trade receivables, contractual amount			$ 35,405
Trade receivables			35,405
Inventories			5,282
Other current assets (excluding cash)			13,917
Property, plant and equipment			88,605
Goodwill			280,711
Definite-lived intangible assets			162,400
Other long-term assets			20,163
Deferred revenue			(15,278)
Current liabilities			(46,081)
Deferred tax liabilities			(27,458)
Other long-term liabilities			(22,624)
Redeemable noncontrolling interest			(4,035)
Total purchase price allocation			$ 491,007
MPI Research
Business Acquisition [Line Items]
Acquired trade receivables, contractual amount					$ 35,073
Trade receivables					35,073
Inventories					4,463
Other current assets (excluding cash)					5,893
Property, plant and equipment					128,403
Goodwill					441,656
Definite-lived intangible assets					309,200
Other long-term assets					1,081
Deferred revenue					(23,926)
Current liabilities					(32,885)
Deferred tax liabilities					(65,945)
Other long-term liabilities					(2,213)
Total purchase price allocation					$ 800,800
KWS BioTest Limited
Business Acquisition [Line Items]
Acquired trade receivables, contractual amount						$ 1,309
Trade receivables						1,309
Other current assets (excluding cash)						99
Property, plant and equipment						1,136
Goodwill						17,660
Definite-lived intangible assets						3,647
Deferred revenue						(151)
Current liabilities						(1,575)
Other long-term liabilities						(596)
Total purchase price allocation						$ 21,529
Brains On-Line
Business Acquisition [Line Items]
Acquired trade receivables, contractual amount								$ 1,146
Trade receivables								1,146
Other current assets (excluding cash)								640
Property, plant and equipment								664
Goodwill								12,582
Definite-lived intangible assets								9,300
Other long-term assets								29
Deferred revenue								(405)
Current liabilities								(1,683)
Other long-term liabilities								(2,151)
Total purchase price allocation								$ 20,122
Other Acquisitions
Business Acquisition [Line Items]
Acquired trade receivables, contractual amount		$ 189
Trade receivables		189
Inventories		7,644
Property, plant and equipment		1,462
Goodwill		12,669
Other long-term assets		11,849
Current liabilities		(441)
Deferred tax liabilities		(1,331)
Other long-term liabilities		(238)
Redeemable noncontrolling interest		(8,740)
Total purchase price allocation		$ 23,063

BUSINESS COMBINATIONS AND DIV_5

BUSINESS COMBINATIONS AND DIVESTITURE - Definite Lived Intangible Assets (Details) - USD ($) $ in Thousands	Apr. 29, 2019	Apr. 03, 2018	Aug. 04, 2017
Citoxlab
Business Acquisition [Line Items]
Definite-Lived Intangible Assets	$ 162,400
Weighted Average Amortization Life	12 years
MPI Research
Business Acquisition [Line Items]
Definite-Lived Intangible Assets		$ 309,200
Weighted Average Amortization Life		12 years
Brains On-Line
Business Acquisition [Line Items]
Definite-Lived Intangible Assets			$ 9,300
Weighted Average Amortization Life			12 years
Client relationships | Citoxlab
Business Acquisition [Line Items]
Definite-Lived Intangible Assets	$ 134,600
Weighted Average Amortization Life	13 years
Client relationships | MPI Research
Business Acquisition [Line Items]
Definite-Lived Intangible Assets		$ 264,900
Weighted Average Amortization Life		13 years
Client relationships | Brains On-Line
Business Acquisition [Line Items]
Definite-Lived Intangible Assets			$ 7,000
Weighted Average Amortization Life			13 years
Developed technology | Citoxlab
Business Acquisition [Line Items]
Definite-Lived Intangible Assets	$ 19,900
Weighted Average Amortization Life	3 years
Developed technology | MPI Research
Business Acquisition [Line Items]
Definite-Lived Intangible Assets		$ 23,400
Weighted Average Amortization Life		3 years
Developed technology | Brains On-Line
Business Acquisition [Line Items]
Definite-Lived Intangible Assets			$ 2,300
Weighted Average Amortization Life			10 years
Backlog | Citoxlab
Business Acquisition [Line Items]
Definite-Lived Intangible Assets	$ 7,900
Weighted Average Amortization Life	1 year
Backlog | MPI Research
Business Acquisition [Line Items]
Definite-Lived Intangible Assets		$ 20,900
Weighted Average Amortization Life		1 year

BUSINESS COMBINATIONS AND DIV_6

BUSINESS COMBINATIONS AND DIVESTITURE - Pro Forma Financial Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Citoxlab
Business Acquisition [Line Items]
Revenue	$ 2,683,610	$ 2,442,283
Net income attributable to common shareholders	$ 268,995	233,288
MPI Research
Business Acquisition [Line Items]
Revenue		2,328,213	$ 2,095,385
Net income attributable to common shareholders		$ 225,550	$ 126,641

BUSINESS COMBINATIONS AND DIV_7

BUSINESS COMBINATIONS AND DIVESTITURE - Contract Manufacturing, Schedule of Assets and Liabilities Disposed (Details) - CDMO Business - Disposal Group, Disposed of by Sale, Not Discontinued Operations $ in Thousands	Feb. 10, 2017USD ($)
Assets
Current assets	$ 5,505
Property, plant and equipment, net	11,174
Goodwill	35,857
Long-term assets	17,154
Total assets	69,690
Liabilities
Deferred revenue	4,878
Other current liabilities	1,158
Total liabilities	$ 6,036

REVENUE FROM CONTRACTS WITH C_3

REVENUE FROM CONTRACTS WITH CUSTOMERS - Disaggregation of Revenues by Major Business Line (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Disaggregation of Revenue [Line Items]
Revenue	$ 691,138	$ 667,951	$ 657,568	$ 604,569	$ 601,530	$ 585,295	$ 585,301	$ 493,970	$ 2,621,226	$ 2,266,096	$ 1,857,601
RMS
Disaggregation of Revenue [Line Items]
Revenue									537,089	519,682	493,615
RMS | Services and products transferred over time
Disaggregation of Revenue [Line Items]
Revenue									227,872	202,872
RMS | Services and products transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenue									309,217	316,810
DSA
Disaggregation of Revenue [Line Items]
Revenue									1,618,995	1,316,854	980,022
DSA | Services and products transferred over time
Disaggregation of Revenue [Line Items]
Revenue									1,618,281	1,316,005
DSA | Services and products transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenue									714	849
Manufacturing
Disaggregation of Revenue [Line Items]
Revenue									465,142	429,560	$ 383,964
Manufacturing | Services and products transferred over time
Disaggregation of Revenue [Line Items]
Revenue									142,896	128,287
Manufacturing | Services and products transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenue									$ 322,246	$ 301,273

REVENUE FROM CONTRACTS WITH C_4

REVENUE FROM CONTRACTS WITH CUSTOMERS - Schedule of Estimated Revenue Related to Performance Obligations (Details) $ in Thousands	Dec. 28, 2019USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-12-29
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 167,729
Performance obligations expected to be satisfied, expected timing	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 101,274
Performance obligations expected to be satisfied, expected timing	2 years
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 5,984
Performance obligations expected to be satisfied, expected timing	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 540
Performance obligations expected to be satisfied, expected timing
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 275,527
DSA | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-12-29
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	156,125
DSA | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	89,458
DSA | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	5,965
DSA | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	527
DSA | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	252,075
Manufacturing | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-12-29
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	11,604
Manufacturing | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	11,816
Manufacturing | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	19
Manufacturing | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	13
Manufacturing | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 23,452

REVENUE FROM CONTRACTS WITH C_5

REVENUE FROM CONTRACTS WITH CUSTOMERS - Schedule of Client Receivables, Contract Assets and Contract Liabilities (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Revenue from Contract with Customer [Abstract]
Client receivables	$ 395,740	$ 370,131
Contract assets (unbilled revenue)	121,957	105,216
Contract liabilities (current and long-term deferred revenue)	192,788	179,559
Contract liabilities (customer contract deposits)	$ 33,080	$ 38,245

REVENUE FROM CONTRACTS WITH C_6

REVENUE FROM CONTRACTS WITH CUSTOMERS - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018
Revenue from Contract with Customer [Abstract]
Payment terms	30 days
Unpaid advanced client billings	$ 27,000	$ 22,000
Contract liabilities (customer contract deposits)	$ 33,080	$ 38,245
Percentage of unbilled revenue billed during period	95.00%
Percentage of contract liabilities recognized as revenue during period	85.00%

SEGMENT AND GEOGRAPHIC INFORM_3

SEGMENT AND GEOGRAPHIC INFORMATION - Financial Information by Reportable Business Segment (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019USD ($)	Sep. 28, 2019USD ($)	Jun. 29, 2019USD ($)	Mar. 30, 2019USD ($)	Dec. 29, 2018USD ($)	Sep. 29, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 28, 2019USD ($)segments	Dec. 29, 2018USD ($)	Dec. 30, 2017USD ($)
Segment Reporting [Abstract]
Number of reportable segments | segments									3
Segment Reporting Information [Line Items]
Revenue	$ 691,138	$ 667,951	$ 657,568	$ 604,569	$ 601,530	$ 585,295	$ 585,301	$ 493,970	$ 2,621,226	$ 2,266,096	$ 1,857,601
Operating income	$ 108,789	$ 92,802	$ 79,768	$ 69,792	$ 102,482	$ 84,362	$ 76,710	$ 67,829	351,151	331,383	288,282
Depreciation and amortization									198,095	161,779	131,159
Capital expenditures									140,514	140,054	82,431
RMS
Segment Reporting Information [Line Items]
Revenue									537,089	519,682	493,615
Operating income									133,912	136,468	114,588
Depreciation and amortization									19,197	19,469	19,627
Capital expenditures									26,989	35,172	20,879
DSA
Segment Reporting Information [Line Items]
Revenue									1,618,995	1,316,854	980,022
Operating income									258,903	227,577	182,796
Depreciation and amortization									151,139	112,976	79,355
Capital expenditures									86,843	73,425	36,616
Manufacturing
Segment Reporting Information [Line Items]
Revenue									465,142	429,560	383,964
Operating income									145,420	136,212	123,898
Depreciation and amortization									23,584	22,529	22,893
Capital expenditures									$ 23,617	$ 23,323	$ 15,188

SEGMENT AND GEOGRAPHIC INFORM_4

SEGMENT AND GEOGRAPHIC INFORMATION - Reconciliation of Segment Operating Income, Depreciation, Amortization and Capital Expenditures (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Segment Reporting Information [Line Items]
Operating income	$ 108,789	$ 92,802	$ 79,768	$ 69,792	$ 102,482	$ 84,362	$ 76,710	$ 67,829	$ 351,151	$ 331,383	$ 288,282
Depreciation and Amortization									198,095	161,779	131,159
Capital Expenditures									140,514	140,054	82,431
Total reportable segments
Segment Reporting Information [Line Items]
Operating income									538,235	500,257	421,282
Depreciation and Amortization									193,920	154,974	121,875
Capital Expenditures									137,449	131,920	72,683
Unallocated corporate
Segment Reporting Information [Line Items]
Operating income									(187,084)	(168,874)	(133,000)
Depreciation and Amortization									4,175	6,805	9,284
Capital Expenditures									$ 3,065	$ 8,134	$ 9,748

SEGMENT AND GEOGRAPHIC INFORM_5

SEGMENT AND GEOGRAPHIC INFORMATION - Revenue by Product and Service Offering (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Segment Reporting Information [Line Items]
Revenue	$ 691,138	$ 667,951	$ 657,568	$ 604,569	$ 601,530	$ 585,295	$ 585,301	$ 493,970	$ 2,621,226	$ 2,266,096	$ 1,857,601
RMS
Segment Reporting Information [Line Items]
Revenue									537,089	519,682	493,615
DSA
Segment Reporting Information [Line Items]
Revenue									1,618,995	1,316,854	980,022
Manufacturing
Segment Reporting Information [Line Items]
Revenue									$ 465,142	$ 429,560	$ 383,964

SEGMENT AND GEOGRAPHIC INFORM_6

SEGMENT AND GEOGRAPHIC INFORMATION - Unallocated Corporate Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Segment Reporting Information [Line Items]
Stock-based compensation	$ 57,271	$ 47,346	$ 44,003
Depreciation	108,600	96,900	89,800
Unallocated corporate
Segment Reporting Information [Line Items]
Stock-based compensation	37,855	32,068	27,114
Compensation, benefits, and other employee-related expenses	73,893	69,191	46,920
External consulting and other service expenses	16,639	18,652	22,224
Information technology	16,080	12,463	11,997
Depreciation	4,175	6,805	9,284
Acquisition and integration	26,877	16,295	3,728
Other general unallocated corporate	11,565	13,400	11,733
Total unallocated corporate expense	$ 187,084	$ 168,874	$ 133,000

SEGMENT AND GEOGRAPHIC INFORM_7

SEGMENT AND GEOGRAPHIC INFORMATION - Revenue and Long-Lived Assets by Geographic Segment (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Segment Reporting Information [Line Items]
Revenue	$ 691,138	$ 667,951	$ 657,568	$ 604,569	$ 601,530	$ 585,295	$ 585,301	$ 493,970	$ 2,621,226	$ 2,266,096	$ 1,857,601
Long-lived assets	1,044,128				932,877				1,044,128	932,877	781,973
U.S.
Segment Reporting Information [Line Items]
Revenue									1,471,097	1,267,620	959,263
Long-lived assets	602,654				597,223				602,654	597,223	446,574
Europe
Segment Reporting Information [Line Items]
Revenue									726,421	643,957	569,812
Long-lived assets	253,665				205,185				253,665	205,185	203,911
Canada
Segment Reporting Information [Line Items]
Revenue									271,987	206,382	200,343
Long-lived assets	127,495				74,051				127,495	74,051	82,228
Asia Pacific
Segment Reporting Information [Line Items]
Revenue									146,218	142,495	126,462
Long-lived assets	60,213				56,262				60,213	56,262	49,020
Other
Segment Reporting Information [Line Items]
Revenue									5,503	5,642	1,721
Long-lived assets	$ 101				$ 156				$ 101	$ 156	$ 240

SUPPLEMENTAL BALANCE SHEET IN_3

SUPPLEMENTAL BALANCE SHEET INFORMATION - Composition of Trade Receivables, Net (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Supplemental Balance Sheet Information [Abstract]
Client receivables	$ 395,740	$ 370,131
Unbilled revenue	121,957	105,216
Total	517,697	475,347
Less: Allowance for doubtful accounts	(3,664)	(3,099)
Trade receivables, net	$ 514,033	$ 472,248

SUPPLEMENTAL BALANCE SHEET IN_4

SUPPLEMENTAL BALANCE SHEET INFORMATION - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Provisions to allowance for doubtful accounts	$ 3	$ 2.1	$ 0.9
Depreciation	$ 108.6	$ 96.9	$ 89.8

SUPPLEMENTAL BALANCE SHEET IN_5

SUPPLEMENTAL BALANCE SHEET INFORMATION - Composition of Inventories (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Supplemental Balance Sheet Information [Abstract]
Raw materials and supplies	$ 24,613	$ 22,378
Work in process	35,852	21,732
Finished products	100,195	83,782
Inventories	$ 160,660	$ 127,892

SUPPLEMENTAL BALANCE SHEET IN_6

SUPPLEMENTAL BALANCE SHEET INFORMATION - Composition of Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Supplemental Balance Sheet Information [Abstract]
Prepaid income tax	$ 54,358	$ 47,157
Short-term investments	941	885
Restricted cash	431	465	$ 592
Other	300	300
Other current assets	$ 56,030	$ 48,807

SUPPLEMENTAL BALANCE SHEET IN_7

SUPPLEMENTAL BALANCE SHEET INFORMATION - Composition of Property, Plant and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 30, 2018	Dec. 29, 2018
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 2,021,698		$ 1,807,012
Less: Accumulated depreciation	(977,570)		(874,135)
Property, plant and equipment, net	1,044,128	$ 909,429	932,877
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	63,077		52,266
Buildings
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	1,006,357		938,184
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	585,965		501,894
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	84,630		59,854
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	28,304		26,700
Computer hardware and software
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	179,865		166,398
Vehicles
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	5,561		5,167
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 67,939		$ 56,549

SUPPLEMENTAL BALANCE SHEET IN_8

SUPPLEMENTAL BALANCE SHEET INFORMATION - Composition of Other Assets (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 30, 2018	Dec. 29, 2018	Dec. 30, 2017
Supplemental Balance Sheet Information [Abstract]
Venture capital investments	$ 108,983		$ 87,545
Other investments	13,996		1,046
Life insurance policies	38,207		32,340
Restricted cash	1,601		1,411	$ 1,945
Other	49,828		21,417
Other assets	$ 212,615	$ 138,770	$ 143,759

SUPPLEMENTAL BALANCE SHEET IN_9

SUPPLEMENTAL BALANCE SHEET INFORMATION - Composition of Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 30, 2018	Dec. 29, 2018
Supplemental Balance Sheet Information [Abstract]
Current portion of operating lease right-of-use liabilities	$ 20,357
Accrued income taxes	26,066		$ 24,120
Customer contract deposits	33,080		38,245
Other	11,095		8,915
Other current liabilities	$ 90,598	$ 87,215	$ 71,280

SUPPLEMENTAL BALANCE SHEET I_10

SUPPLEMENTAL BALANCE SHEET INFORMATION - Composition of Other Long-Term Liabilities (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Supplemental Balance Sheet Information [Abstract]
U.S. Transition Tax	$ 52,066	$ 52,064
Long-term pension liability	43,054	24,671
Accrued executive supplemental life insurance retirement plan and deferred compensation plan	37,779	36,086
Long-term deferred revenue	20,983	34,420
Other	29,051	31,880
Other long-term liabilities	$ 182,933	$ 179,121

VENTURE CAPITAL INVESTMENTS A_2

VENTURE CAPITAL INVESTMENTS AND OTHER INVESTMENTS - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Marketable Securities and Equity-Method Affiliates [Abstract]
Venture capital investments	$ 108,983	$ 87,545
Total commitment	128,400
Amount funded for venture capital investments	80,300
Dividends received	11,400	18,200	$ 10,100
Gains related to venture capital investments	(20,706)	(15,928)	$ (22,867)
Consolidated retained earnings	20,600	14,100
Other investments	$ 13,996	$ 1,046

FAIR VALUE - Assets and Liabili

FAIR VALUE - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	$ 55,278	$ 45,982
Other assets:
Life insurance policies	30,454	24,541
Total assets measured at fair value	85,732	70,523
Other current liabilities measured at fair value:
Contingent consideration	712	3,033
Foreign currency forward contract	876	1,319
Total liabilities measured at fair value	1,588	4,352
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Other assets:
Life insurance policies	0	0
Total assets measured at fair value	0	0
Other current liabilities measured at fair value:
Contingent consideration	0	0
Foreign currency forward contract	0	0
Total liabilities measured at fair value	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	55,278	45,982
Other assets:
Life insurance policies	30,454	24,541
Total assets measured at fair value	85,732	70,523
Other current liabilities measured at fair value:
Contingent consideration	0	0
Foreign currency forward contract	876	1,319
Total liabilities measured at fair value	876	1,319
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Other assets:
Life insurance policies	0	0
Total assets measured at fair value	0	0
Other current liabilities measured at fair value:
Contingent consideration	712	3,033
Foreign currency forward contract	0	0
Total liabilities measured at fair value	$ 712	$ 3,033

FAIR VALUE - Rollforward of Con

FAIR VALUE - Rollforward of Contingent Consideration (Details) - Contingent Consideration - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 3,033	$ 298
Additions	2,869	3,315
Payments	(5,252)	0
Total gains or losses (realized/unrealized):
Foreign currency translation	62	(298)
Reversal of previously recorded contingent liability and change in fair value	0	(282)
Ending balance	$ 712	$ 3,033

FAIR VALUE - Debt Instruments (

FAIR VALUE - Debt Instruments (Details) - Senior Notes - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
2026 Senior Notes | Book Value
Debt Instrument [Line Items]
Value of debt instruments	$ 500,000	$ 500,000
2026 Senior Notes | Fair Value
Debt Instrument [Line Items]
Value of debt instruments	537,500	495,000
2028 Senior Notes | Book Value
Debt Instrument [Line Items]
Value of debt instruments	500,000	0
2028 Senior Notes | Fair Value
Debt Instrument [Line Items]
Value of debt instruments	$ 510,000	$ 0

GOODWILL AND INTANGIBLE ASSET_2

GOODWILL AND INTANGIBLE ASSETS - Rollforward of Company's Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Goodwill [Roll Forward]
Gross carrying amount, beginning balance	$ 2,252,133	$ 1,809,906
Adjustments to goodwill, acquisitions	293,380	462,774
Adjustments to goodwill, foreign exchange	52	(20,547)
Gross carrying amount, ending balance	2,545,565	2,252,133
Accumulated impairment loss - DSA	(1,005,000)	(1,005,000)	$ (1,005,000)
Goodwill	1,540,565	1,247,133	$ 804,906
RMS
Goodwill [Roll Forward]
Gross carrying amount, beginning balance	56,968	58,122
Adjustments to goodwill, acquisitions	0	0
Adjustments to goodwill, foreign exchange	(382)	(1,154)
Gross carrying amount, ending balance	56,586	56,968
DSA
Goodwill [Roll Forward]
Gross carrying amount, beginning balance	2,056,470	1,610,176
Adjustments to goodwill, acquisitions	293,380	460,223
Adjustments to goodwill, foreign exchange	373	(13,929)
Gross carrying amount, ending balance	2,350,223	2,056,470
Manufacturing
Goodwill [Roll Forward]
Gross carrying amount, beginning balance	138,695	141,608
Adjustments to goodwill, acquisitions	0	2,551
Adjustments to goodwill, foreign exchange	61	(5,464)
Gross carrying amount, ending balance	$ 138,756	$ 138,695

GOODWILL AND INTANGIBLE ASSET_3

GOODWILL AND INTANGIBLE ASSETS - Intangible Assets, Net by Major Class (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Finite-lived intangible assets
Gross	$ 1,112,348	$ 939,910
Accumulated Amortization	(422,935)	(329,022)
Net	689,413	610,888
Backlog
Finite-lived intangible assets
Gross	28,865	20,900
Accumulated Amortization	(26,895)	(18,691)
Net	1,970	2,209
Technology
Finite-lived intangible assets
Gross	122,106	101,506
Accumulated Amortization	(57,737)	(41,870)
Net	64,369	59,636
Trademarks and trade names
Finite-lived intangible assets
Gross	8,430	8,331
Accumulated Amortization	(4,901)	(4,640)
Net	3,529	3,691
Other
Finite-lived intangible assets
Gross	18,279	17,448
Accumulated Amortization	(12,307)	(10,041)
Net	5,972	7,407
Other intangible assets
Finite-lived intangible assets
Gross	177,680	148,185
Accumulated Amortization	(101,840)	(75,242)
Net	75,840	72,943
Client relationships
Finite-lived intangible assets
Gross	934,668	791,725
Accumulated Amortization	(321,095)	(253,780)
Net	$ 613,573	$ 537,945

GOODWILL AND INTANGIBLE ASSET_4

GOODWILL AND INTANGIBLE ASSETS - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill impairment	$ 0	$ 0	$ 0
Amortization of intangible assets	$ 89,538,000	$ 64,830,000	$ 41,370,000

GOODWILL AND INTANGIBLE ASSET_5

GOODWILL AND INTANGIBLE ASSETS - Estimated Amortization Expense for Intangible Assets for Next Five Fiscal Years (Details) $ in Thousands	Dec. 28, 2019USD ($)
Estimated amortization expense for each of the next five fiscal years
2020	$ 97,024
2021	87,540
2022	76,204
2023	67,807
2024	$ 60,918

LONG-TERM DEBT AND FINANCE LE_3

LONG-TERM DEBT AND FINANCE LEASE OBLIGATIONS - Long-term Debt, Net (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 30, 2018	Dec. 29, 2018
Debt Instrument [Line Items]
Long-term debt, gross	$ 1,875,665
Finance leases (Note 16)	30,527
Finance leases (Note 16)			$ 29,240
Total debt and finance leases	1,906,192		1,684,228
Current portion of long-term debt and finance leases	35,548		28,228
Current portion of finance leases (Note 16)	2,997
Current portion of finance leases (Note 16)			3,188
Current portion of long-term debt and finance leases	38,545		31,416
Long-term debt and finance leases	1,867,647		1,652,812
Debt discount and debt issuance costs	(17,981)		(16,214)
Long-term debt, net and finance leases	1,849,666	$ 1,610,415	1,636,598
Term loans
Debt Instrument [Line Items]
Long-term debt, gross	193,750		731,250
Revolving facility
Debt Instrument [Line Items]
Long-term debt, gross	676,134		397,452
2026 Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross	500,000		500,000
2028 Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross	500,000		0
Other debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 5,781		$ 26,286

LONG-TERM DEBT AND FINANCE LE_4

LONG-TERM DEBT AND FINANCE LEASE OBLIGATIONS - Additional Information (Details)	Jan. 03, 2020USD ($)	Oct. 23, 2019USD ($)	Apr. 03, 2018USD ($)	Mar. 26, 2018USD ($)payment	Mar. 31, 2018USD ($)	Dec. 28, 2019USD ($)	Dec. 29, 2018USD ($)	Nov. 04, 2019USD ($)	Sep. 29, 2018USD ($)	Feb. 12, 2018USD ($)
Debt Instrument [Line Items]
Weighted average interest rate						3.46%	4.24%
Bridge Facility
Debt Instrument [Line Items]
Amount of credit facility										$ 830,000,000
Capitalized debt issuance costs									$ 1,800,000
Fees paid for temporary backstop facility					$ 2,000,000
Letter of Credit
Debt Instrument [Line Items]
Amount outstanding under letters of credit						$ 7,500,000	$ 6,500,000
Credit facility | $1.65 Billion Credit Facility
Debt Instrument [Line Items]
Amount of credit facility				$ 1,650,000,000
Credit facility | $2.3 Billion Credit Facility
Debt Instrument [Line Items]
Amount of credit facility				2,300,000,000
Capitalized debt issuance costs							6,200,000
Expensed debt issuance costs				1,600,000			1,000,000
Credit facility | Term Loan Facility
Debt Instrument [Line Items]
Amount of credit facility				$ 750,000,000
Number of quarterly installment payments | payment				19
Pre-payments of long-term debt		$ 500,000,000
Credit facility | $1.55 Billion Credit Facility | Multi-currency Revolving Facility
Debt Instrument [Line Items]
Amount of credit facility								$ 1,550,000,000
Credit facility | $2.5 Billion Credit Facility
Debt Instrument [Line Items]
Minimum EBITDA less capital expenditures to consolidated cash interest expense				3.50
Credit facility | $2.5 Billion Credit Facility | Federal Funds Rate
Debt Instrument [Line Items]
Interest rate				0.50%
Credit facility | $2.5 Billion Credit Facility | LIBOR
Debt Instrument [Line Items]
Interest rate				1.00%
Credit facility | $2.5 Billion Credit Facility | Multi-currency Revolving Facility
Debt Instrument [Line Items]
Amount of credit facility								2,050,000,000
Maximum increase to the term loan and/or revolving line of credit								1,000,000,000
Senior Notes | 2028 Senior Notes
Debt Instrument [Line Items]
Capitalized debt issuance costs		6,000,000				$ 500,000
Proceeds from private offering of debt		500,000,000
Aggregate principal amount		$ 500,000,000						$ 500,000,000
Maximum consolidated indebtedness to consolidated EBITDA, with step downs								4
Stated interest rate						4.25%
Redemption price percentage, conditional upon equity offerings		40.00%
Redemption price percentage in the event of a change of control		101.00%
Net proceeds from debt		$ 494,000,000
Senior Notes | 2028 Senior Notes | Redemption Period One
Debt Instrument [Line Items]
Redemption price percentage		100.00%
Senior Notes | 2028 Senior Notes | Redemption Period Two
Debt Instrument [Line Items]
Redemption price percentage		104.25%
Senior Notes | 2026 Senior Notes
Debt Instrument [Line Items]
Capitalized debt issuance costs			$ 7,400,000
Aggregate principal amount			$ 500,000,000
Stated interest rate						5.50%
Redemption price percentage, conditional upon equity offerings			40.00%
Redemption price percentage in the event of a change of control			101.00%
Net proceeds from debt			$ 493,800,000
Senior Notes | 2026 Senior Notes | Redemption Period One
Debt Instrument [Line Items]
Redemption price percentage			100.00%
Senior Notes | 2026 Senior Notes | Redemption Period Two
Debt Instrument [Line Items]
Redemption price percentage			105.50%
Minimum | Foreign Exchange Forward
Debt Instrument [Line Items]
Foreign exchange forward contract amount						$ 300,000,000
Maximum | Foreign Exchange Forward
Debt Instrument [Line Items]
Foreign exchange forward contract amount						400,000,000
HemaCare Corporation | Subsequent Event
Debt Instrument [Line Items]
Purchase price	$ 380,000,000
Other income, net | Foreign Exchange Forward
Debt Instrument [Line Items]
Foreign currency translation loss recognized						9,600,000	100,000
Amount of gain (loss)						(121,000)
Interest expense | Foreign Exchange Forward
Debt Instrument [Line Items]
Amount of gain (loss)						$ 18,672,000	$ 1,486,000

LONG-TERM DEBT AND FINANCE LE_5

LONG-TERM DEBT AND FINANCE LEASE OBLIGATIONS - Principal Maturities of Long Term Debt (Details) $ in Thousands	Dec. 28, 2019USD ($)
Debt Disclosure [Abstract]
2020	$ 35,536
2021	61,151
2022	93,966
2023	682,602
2024	468
Thereafter	1,001,942
Total debt	$ 1,875,665

EQUITY AND NONCONTROLLING INT_3

EQUITY AND NONCONTROLLING INTERESTS - Reconciliation of Numerator and Denominator in the Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Numerator:
Income from continuing operations, net of income taxes									$ 254,061	$ 227,218	$ 125,586
Income (loss) from discontinued operations, net of income taxes									0	1,506	(137)
Less: Net income attributable to noncontrolling interests									2,042	2,351	2,094
Net income attributable to common shareholders	$ 80,348	$ 72,810	$ 43,728	$ 55,133	$ 59,665	$ 60,368	$ 53,709	$ 52,631	$ 252,019	$ 226,373	$ 123,355
Denominator:
Weighted-average shares outstanding—Basic (in shares)									48,730	47,947	47,481
Effect of dilutive securities:
Stock options, restricted stock, restricted stock units and performance share units (in shares)									963	1,071	1,083
Weighted-average shares outstanding—Diluted (in shares)									49,693	49,018	48,564

EQUITY AND NONCONTROLLING INT_4

EQUITY AND NONCONTROLLING INTERESTS - Earnings Per Share, Additional Information (Details) - shares shares in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average shares outstanding—Diluted (in shares)	49,693	49,018	48,564
Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	400	500	600
Restricted Stock, Restricted Stock Units, and PSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average shares outstanding—Diluted (in shares)	1,000	1,000	1,100

EQUITY AND NONCONTROLLING INT_5

EQUITY AND NONCONTROLLING INTERESTS - Treasury Shares, Additional Information (Details) - USD ($)	1 Months Ended	12 Months Ended
	Jul. 31, 2010	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017	Dec. 27, 2014	Dec. 28, 2013	Dec. 25, 2010
Treasury Shares and Accelerated Stock Repurchase Program (ASR) [Line Items]
Value of shares repurchased		$ 18,087,000	$ 13,846,000	$ 106,909,000
Shares acquired for individual minimum statutory tax withholding (in shares)		100,000	100,000	200,000
Value of shares acquired for individual minimum statutory tax withholding		$ 18,100,000	$ 13,800,000	$ 16,300,000
Treasury shares retired (in shares)		100,000	40,200,000
Retirement of treasury shares		$ 18,100,000	$ 1,700,000,000
2010 Share Repurchase Program
Treasury Shares and Accelerated Stock Repurchase Program (ASR) [Line Items]
Authorized increases to share repurchase program	$ 500,000,000			150,000,000	$ 150,000,000	$ 250,000,000	$ 250,000,000
Aggregate authorization of share repurchase program				$ 1,300,000,000
Number of shares repurchased (in shares)		0	0	1,000,000
Value of shares repurchased		$ 0	$ 0	$ 90,600,000
Amount remaining on the authorized share repurchase program		129,100,000
Retained Earnings
Treasury Shares and Accelerated Stock Repurchase Program (ASR) [Line Items]
Retirement of treasury shares		13,786,000	477,689,000
Additional Paid-In Capital
Treasury Shares and Accelerated Stock Repurchase Program (ASR) [Line Items]
Retirement of treasury shares		$ 4,355,000	$ 1,195,614,000

EQUITY AND NONCONTROLLING INT_6

EQUITY AND NONCONTROLLING INTERESTS - Changes to Accumulated Other Comprehensive Income (Loss), Net of Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Increase (Decrease) in Stockholders' Equity
Beginning balance	$ 1,319,778	$ 1,047,407	$ 839,125
Other comprehensive income (loss) before reclassifications	(10,721)	(29,011)
Amounts reclassified from accumulated other comprehensive income (loss)	1,772	2,477
Net current period other comprehensive (loss) income	(8,949)	(26,534)
Amount reclassified from accumulated other comprehensive loss due to the adoption of ASU 2018-02 (See Note 1)		3,330
Income tax (benefit)	(3,633)	(1,892)	7,954
Ending balance	1,637,828	1,319,778	1,047,407
Foreign Currency Translation Adjustment and Other
Increase (Decrease) in Stockholders' Equity
Beginning balance	(102,199)	(77,545)
Other comprehensive income (loss) before reclassifications	14,444	(27,352)
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Net current period other comprehensive (loss) income	14,444	(27,352)
Amount reclassified from accumulated other comprehensive loss due to the adoption of ASU 2018-02 (See Note 1)		0
Income tax (benefit)	(177)	(2,698)
Ending balance	(87,578)	(102,199)	(77,545)
Pension and Other Post-Retirement Benefit Plans
Increase (Decrease) in Stockholders' Equity
Beginning balance	(70,504)	(67,186)
Other comprehensive income (loss) before reclassifications	(25,165)	(1,659)
Amounts reclassified from accumulated other comprehensive income (loss)	1,772	2,477
Net current period other comprehensive (loss) income	(23,393)	818
Amount reclassified from accumulated other comprehensive loss due to the adoption of ASU 2018-02 (See Note 1)		3,330
Income tax (benefit)	(3,456)	806
Ending balance	(90,441)	(70,504)	(67,186)
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity
Beginning balance	(172,703)	(144,731)	(253,764)
Ending balance	$ (178,019)	$ (172,703)	$ (144,731)

EQUITY AND NONCONTROLLING INT_7

EQUITY AND NONCONTROLLING INTERESTS - Nonredeemable and Redeemable Noncontrolling Interest, Additional Information (Details) - USD ($) $ in Thousands	Jun. 13, 2019	Apr. 29, 2019	Jul. 07, 2016	Jan. 01, 2013	Dec. 28, 2019	Aug. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Schedule of Investments [Line Items]
Redeemable noncontrolling interests					$ 28,647		$ 18,525	$ 16,609
Citoxlab
Schedule of Investments [Line Items]
Purchase price		$ 527,700
Cash acquired		$ 36,700
Redeemable noncontrolling interest, contractually defined redemption value					4,000
Vital River
Schedule of Investments [Line Items]
Purchase price				$ 24,200
Cash acquired				$ 2,700
Purchase price of additional equity interest	$ 7,900		$ 10,800
Gain in equity equal to the excess fair value of additional equity interest purchased	800
Charge in other income, net equal to the excess fair value of the hybrid equity instrument	$ 2,200
Redeemable noncontrolling interests					$ 15,500		$ 18,500
Vital River
Schedule of Investments [Line Items]
Additional equity interest percentage purchased	5.00%		12.00%	75.00%
Remaining ownership interest	8.00%		13.00%	25.00%
Ownership percentage	92.00%		87.00%
Citoxlab
Schedule of Investments [Line Items]
Remaining ownership interest		10.00%
Ownership percentage		90.00%
Supplier
Schedule of Investments [Line Items]
Remaining ownership interest		20.00%				20.00%
Ownership percentage						80.00%

EQUITY AND NONCONTROLLING INT_8

EQUITY AND NONCONTROLLING INTERESTS - Rollforward of Redeemable Noncontrolling Interest (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Aug. 28, 2019	Jun. 13, 2019	Apr. 29, 2019	Jul. 07, 2016	Jan. 01, 2013
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance	$ 18,525	$ 16,609
Adjustment to Vital River redemption value	1,451	2,069
Purchase of 12% equity	(1,870)
Net (loss) income attributable to noncontrolling interests	(42)	800
Foreign currency translation	(221)	(953)
Ending balance	28,647	18,525
Supplier
Increase (Decrease) in Temporary Equity [Roll Forward]
Acquisition of non-controlling interest	8,740	0
Remaining ownership interest			20.00%		20.00%
Vital River
Increase (Decrease) in Temporary Equity [Roll Forward]
Purchase of 12% equity	(8,745)	0
Change in fair value, included in additional paid-in capital	2,708	0
Modification of Vital River 8% purchase option	2,196	0
Additional equity interest percentage purchased				5.00%		12.00%	75.00%
Remaining ownership interest				8.00%		13.00%	25.00%
Citoxlab
Increase (Decrease) in Temporary Equity [Roll Forward]
Acquisition of non-controlling interest	$ 4,035	$ 0
Remaining ownership interest					10.00%

INCOME TAXES - Components of I

INCOME TAXES - Components of Income from Continuing Operations Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Income from continuing operations before income taxes:
U.S.	$ 108,326	$ 95,062	$ 123,896
Non-U.S.	195,758	186,619	173,059
Income from continuing operations, before income taxes	304,084	281,681	296,955
Current:
Federal	18,101	17,390	93,871
Foreign	43,489	38,557	37,150
State	9,915	8,837	12,361
Total current	71,505	64,784	143,382
Deferred:
Federal	(3,226)	(7,145)	9,416
Foreign	(17,111)	(4,104)	14,953
State	(1,145)	928	3,618
Total deferred	(21,482)	(10,321)	27,987
Provision for income taxes	$ 50,023	$ 54,463	$ 171,369

INCOME TAXES - Additional Info

INCOME TAXES - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Income Tax Contingency [Line Items]
Tax expense	$ 50,023,000	$ 54,463,000	$ 171,369,000
Tax benefit recognized for operating loss carryforwards previously not likely to be utilized	20,600,000
Operating loss carryforwards	315,500,000
Amount of operating loss carryforward, valuation allowance unlikely to be utilized	294,900,000
Increase in valuation allowance	300,200,000
Valuation allowance	309,962,000	9,788,000
Increase in unrecognized income tax benefits	800,000
Unrecognized tax benefits that would impact effective tax rate	17,000,000	17,600,000
Decrease in unrecognized income tax benefits that would impact tax rate	600,000
Decrease in unrecognized tax benefits that is reasonably possible	4,000,000
Accrued interest related to unrecognized income tax benefits	2,300,000	2,700,000
Accrued penalties related to unrecognized income tax benefits	0	0
Foreign Tax Authority
Income Tax Contingency [Line Items]
Operating loss carryforwards	337,300,000	$ 35,700,000
Foreign Tax Authority | Tax Credit Carryforwards, Expiring in 2028 and Beyond
Income Tax Contingency [Line Items]
Tax credit carryforward	30,100,000
Foreign Tax Authority | Net Operating Loss Carryforward, Expiring after 2018
Income Tax Contingency [Line Items]
Operating loss carryforwards	23,300,000
Foreign Tax Authority | Net Operating Loss Carryforward, Carried Forward Indefinitely
Income Tax Contingency [Line Items]
Operating loss carryforwards	$ 314,000,000

INCOME TAXES - Reconciliation

INCOME TAXES - Reconciliation of US Statutory Tax Rate and Effective Tax Rate (Details)	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Income Tax Disclosure [Abstract]
U.S. statutory income tax rate	21.00%	21.00%	35.00%
Foreign tax rate differences	2.70%	0.50%	(6.80%)
State income taxes, net of federal tax benefit	2.60%	2.40%	2.00%
Non-deductible compensation	1.70%	1.00%	1.30%
Research tax credits and enhanced deductions	(4.40%)	(2.90%)	(2.40%)
Stock-based compensation	(2.20%)	(2.10%)	(3.20%)
Enacted tax rate changes	(0.70%)	(0.10%)	(4.20%)
Transition Tax	0.00%	(0.30%)	24.80%
Impact of tax uncertainties	(2.60%)	(1.10%)	(0.40%)
Tax on unremitted earnings	1.70%	1.20%	7.30%
Impact of acquisitions and restructuring	2.70%	0.30%	3.80%
Net operating loss deferred tax asset recognition, net of valuation allowance (NOL DTA)	(6.80%)	0.00%	0.00%
Other	0.80%	(0.60%)	0.50%
Effective income tax rate	16.50%	19.30%	57.70%

INCOME TAXES - Deferred Taxes

INCOME TAXES - Deferred Taxes (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Deferred tax assets:
Compensation	$ 40,582	$ 36,724
Accruals and reserves	13,687	13,183
Net operating loss and credit carryforwards	367,269	35,679
Operating lease liability	33,785
Other	7,181	5,060
Valuation allowance	(309,962)	(9,788)
Total deferred tax assets	152,542	80,858
Deferred tax liabilities:
Goodwill and other intangibles	(174,847)	(154,743)
Depreciation related	(29,317)	(19,373)
Venture capital investments	(12,806)	(10,557)
Tax on unremitted earnings	(17,282)	(14,140)
Right-of-use assets	(34,953)
Other	(5,961)	(2,296)
Total deferred tax liabilities	(275,166)	(201,109)
Net deferred taxes	$ (122,624)	$ (120,251)

INCOME TAXES - Change in Tax P

INCOME TAXES - Change in Tax Positions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Reconciliation of Unrecognized Tax Benefits
Beginning balance	$ 18,827	$ 24,710	$ 24,186
Additions to tax positions for current year	3,691	2,477	1,791
Additions to tax positions for prior years	5,234	0	1,428
Reductions to tax positions for prior years	(1,033)	(4,543)	0
Settlements	(274)	(3,380)	(1,754)
Expiration of statute of limitations	(6,780)	(437)	(941)
Ending balance	$ 19,665	$ 18,827	$ 24,710

EMPLOYEE BENEFIT PLANS - Addit

EMPLOYEE BENEFIT PLANS - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Defined Benefit Plan Disclosure [Line Items]
Benefit obligations	$ 447,409	$ 362,805	$ 392,964
Plan assets	357,181	305,709	304,325
Net periodic benefit cost (income)	$ 4,022	1,332	3,852
Deferral period	3 years
Maximum annual contributions per employee, percent	10.00%
Period of highest consecutive years of compensation	5 years
Costs associated with deferred compensation plan and executive supplemental life insurance retirement plans	$ 2,500	2,900	2,300
Life insurance policies	38,207	32,340
Change in projected benefit obligation based on sensitivity	$ 20,000
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	$ 1,800
Decrease in benefit obligations from new morality improvement scales	2,800	1,700
Employer contributions to participants within plan assets	2,105	31,174
Expected employer contributions in next fiscal year	11,900
Accumulated benefit obligation	1,100	1,500
Costs associated with employee savings plan	19,100	13,400	11,600
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Benefit obligations	94,400
Plan assets	91,200
Actuarial loss	6,000
Unrecognized losses	14,000
Net periodic benefit cost (income)	1,500	(1,500)	$ 1,600
Employer contributions to participants within plan assets	800
Employer contributions to participants outside of plan assets	1,300
Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Plan assets	$ 91,998	72,237
Target asset allocation percentage	24.00%
Fixed Income Securities
Defined Benefit Plan Disclosure [Line Items]
Plan assets	$ 129,965	21,247
Target asset allocation percentage	24.60%
Other Securities
Defined Benefit Plan Disclosure [Line Items]
Plan assets	$ 56,852	$ 58,642
Target asset allocation percentage	51.40%
Executive Officer | Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Benefit obligations	$ 8,000

STOCK-BASED COMPENSATION - Add

STOCK-BASED COMPENSATION - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017	May 31, 2018	May 31, 2016	May 31, 2007
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares to be awarded (in shares)	5,800,000
Capitalized stock-based compensation related costs	$ 0	$ 0	$ 0
Weighted-average grant date fair value of stock options granted (in dollars per share)	$ 33.97	$ 24.80	$ 18.33
Stock-based compensation	$ 57,271,000	$ 47,346,000	$ 44,003,000
2007 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equivalent shares (in shares)						1
2016 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equivalent shares (in shares)					1
2018 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equivalent shares (in shares)				1
Maximum | 2007 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares to be awarded (in shares)						18,700,000
Maximum | 2016 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares to be awarded (in shares)					6,100,000
Maximum | 2018 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares to be awarded (in shares)				7,200,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, expiration period	5 years	5 years	5 years
Unrecognized compensation cost related to unvested stock options expected to vest	$ 16,500,000
Weighted average vesting period of unvested stock options expected to vest	2 years 3 months 18 days
Intrinsic value of options exercised	$ 27,000,000	$ 29,000,000	$ 30,000,000
Stock Options | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years	4 years	4 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average vesting period of unvested stock options expected to vest	2 years 3 months 18 days
Unrecognized compensation cost related to unvested restricted stock units expected to vest	$ 32,600,000
Fair value of awards vested	$ 16,500,000	$ 15,500,000	$ 13,600,000
Restricted Stock | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		2 years	2 years
Restricted Stock | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years	4 years
Restricted Stock Units | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years
Restricted Stock Units | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Fair value of awards vested	$ 20,200,000	$ 18,300,000	$ 14,400,000
Maximum number of common shares to be issued upon vesting of PSUs (in shares)	300,000
Stock-based compensation	$ 25,300,000	$ 20,400,000	$ 18,900,000
PSUs | Performance Shares Grantee Group Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PSUs granted (in shares)	15,000	17,000	15,000
Weighted average per share fair value (in dollars per share)	$ 144.67	$ 109.34	$ 88.05
PSUs | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years	3 years	3 years
Number of shares employee is entitled to receive at no cost (in shares)	0	0	0
Restricted Stock, Restricted Stock Units, and PSUs | 2007 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equivalent shares (in shares)						2.3
Restricted Stock, Restricted Stock Units, and PSUs | 2016 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equivalent shares (in shares)					2.3
Restricted Stock, Restricted Stock Units, and PSUs | 2018 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equivalent shares (in shares)				2.3

EMPLOYEE BENEFIT PLANS - Recon

EMPLOYEE BENEFIT PLANS - Reconciliation of Benefit Obligations and Plan Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Change in projected benefit obligations:
Benefit obligation at beginning of year	$ 362,805	$ 392,964
Service cost	2,833	2,612	$ 3,110
Interest cost	11,583	10,850	11,642
Other	850	1,499
Benefit payments	(11,062)	(8,886)
Settlements	(74)	0
Special/Contractual Termination Benefits	166	0
Plan amendments	0	104
Transfer in from acquisition	6,818	0
Actuarial loss (gain)	66,432	(21,168)
Administrative expenses paid	(470)	(195)
Effect of foreign exchange	7,528	(14,975)
Benefit obligation at end of year	447,409	362,805	392,964
Change in fair value of plan assets:
Fair value of plan assets at beginning of year	305,709	304,325
Actual return on plan assets	53,741	(7,419)
Employer contributions	2,105	31,174
Settlements	(74)	0
Transfer in from acquisition	119	0
Benefit payments	(11,062)	(8,886)
Administrative expenses paid	(470)	(195)
Effect of foreign exchange	7,113	(13,290)
Fair value of plan assets at end of year	357,181	305,709	$ 304,325
Net balance sheet liability	90,228	57,096
Amounts recognized in balance sheet:
Noncurrent assets	1,742	3,280
Current liabilities	12,788	1,095
Noncurrent liabilities	$ 79,182	$ 59,281

STOCK-BASED COMPENSATION - Fin

STOCK-BASED COMPENSATION - Financial Statement Line Items in Which Stock-Based Compensation is Located (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation, before income taxes	$ 57,271	$ 47,346	$ 44,003
Provision for income taxes	(9,465)	(9,188)	(13,428)
Stock-based compensation, net of income taxes	47,806	38,158	30,575
Cost of revenue
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation, before income taxes	9,038	6,285	6,509
Selling, general and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation, before income taxes	$ 48,233	$ 41,061	$ 37,494

EMPLOYEE BENEFIT PLANS - Amoun

EMPLOYEE BENEFIT PLANS - Amounts Recognized in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Amounts recognized in accumulated other comprehensive income (loss)
Net actuarial loss	$ 116,930	$ 93,483
Net prior service cost (credit)	(2,096)	(2,585)
Net amount recognized	$ 114,834	$ 90,898

STOCK-BASED COMPENSATION - Sto

STOCK-BASED COMPENSATION - Stock Option Activities (Details) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 28, 2019USD ($)$ / sharesshares
Number of shares
Options outstanding, balance at the beginning of the period (in shares) | shares	1,556
Options granted (in shares) | shares	454
Options exercised (in shares) | shares	(442)
Options canceled (in shares) | shares	(61)
Options outstanding, balance at the end of the period (in shares) | shares	1,507
Weighted Average Exercise Price
Options outstanding, balance at the beginning of the period (in dollars per share) | $ / shares	$ 86.44
Options granted (in dollars per share) | $ / shares	144.42
Options exercised (in dollars per share) | $ / shares	78.49
Options canceled (in dollars per share) | $ / shares	113.17
Options outstanding, balance at the end of the period (in dollars per share) | $ / shares	$ 105.19
Other Disclosures
Options outstanding weighted average remaining contractual life	2 years 8 months 12 days
Options outstanding, aggregate intrinsic value | $	$ 70,459
Options exercisable (in shares) | shares	390
Options exercisable (in dollars per share) | $ / shares	$ 77.87
Options exercisable, weighted average remaining contractual life	1 year 6 months
Options exercisable, aggregate intrinsic value | $	$ 28,897
Options expected to vest (in shares) | shares	1,117
Options expected to vest (in dollars per share) | $ / shares	$ 114.73
Options expected to vest, weighted average remaining contractual life	3 years 1 month 6 days
Options expected to vest, aggregate intrinsic value | $	$ 41,562

EMPLOYEE BENEFIT PLANS - Accum

EMPLOYEE BENEFIT PLANS - Accumulated Benefit Obligation and Fair Value of Plan Assets for Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Plans with Accumulated Benefit Obligations in Excess of Plan Assets
Accumulated benefit obligation	$ 410,243	$ 254,138
Fair value of plan assets	$ 337,344	$ 207,538

STOCK-BASED COMPENSATION - S_2

STOCK-BASED COMPENSATION - Stock Options, Weighted Average Assumptions (Details)	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Share-based Payment Arrangement [Abstract]
Expected life (in years)	3 years 7 months 6 days	3 years 8 months 12 days	3 years 7 months 6 days
Expected volatility	27.00%	25.00%	24.00%
Risk-free interest rate	2.40%	2.40%	1.60%
Expected dividend yield	0.00%	0.00%	0.00%

EMPLOYEE BENEFIT PLANS - Proje

EMPLOYEE BENEFIT PLANS - Projected Benefit Obligation and Fair Value of Plan Assets for Pension Plans with Projected Benefit Obligations in Excess of Plan Assets (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Retirement Benefits [Abstract]
Projected benefit obligation	$ 435,638	$ 273,625
Fair value of plan assets	$ 343,688	$ 213,249

STOCK-BASED COMPENSATION - Res

STOCK-BASED COMPENSATION - Restricted Stock and Restricted Stock Units Activity (Details) - Restricted Stock Units shares in Thousands	12 Months Ended
	Dec. 28, 2019$ / sharesshares
Restricted Stock Units
Balance at the beginning of the period (in shares) | shares	490
Granted (in shares) | shares	221
Vested (in shares) | shares	(185)
Canceled (in shares) | shares	(30)
Balance at the end of the period (in shares) | shares	496
Weighted Average Grant Date Fair Value
Balance at the beginning of the period (in dollars per share) | $ / shares	$ 93.80
Granted (in dollars per share) | $ / shares	142.85
Vested (in dollars per share) | $ / shares	89.34
Canceled (in dollars per share) | $ / shares	115.10
Balance at the end of the period (in dollars per share) | $ / shares	$ 116.07

EMPLOYEE BENEFIT PLANS - Amo_2

EMPLOYEE BENEFIT PLANS - Amounts in Accumulated Other Comprehensive Income Expected to be Recognized as Components of Net Periodic Benefit Cost Over the Next Fiscal Year (Details) $ in Thousands	Dec. 28, 2019USD ($)
Retirement Benefits [Abstract]
Amortization of net actuarial loss	$ 6,344
Amortization of net prior service credit	$ (501)

STOCK-BASED COMPENSATION - Per

STOCK-BASED COMPENSATION - Performance Based Stock Award Program (Details) - $ / shares shares in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Key Assumptions:
Expected volatility	27.00%	25.00%	24.00%
Risk-free interest rate	2.40%	2.40%	1.60%
Expected dividend yield	0.00%	0.00%	0.00%
Trading day average stock price on grant date	20 days
PSU Grantee Group One | PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PSUs granted (in shares)	160	200	198
Key Assumptions:
Expected volatility	25.00%	26.00%	26.00%
Risk-free interest rate	2.40%	2.40%	1.30%
Expected dividend yield	0.00%	0.00%	0.00%
Total shareholder return of 20-trading day average stock price on grant date	17.70%	2.90%	17.70%
PSU Grantee Group One | 2007 Incentive Plan | PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average per share fair value (in dollars per share)	$ 164.47	$ 117.89	$ 99.96

EMPLOYEE BENEFIT PLANS - Compo

EMPLOYEE BENEFIT PLANS - Components of Net Period Benefit Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Retirement Benefits [Abstract]
Service cost	$ 2,833	$ 2,612	$ 3,110
Interest cost	11,583	10,850	11,642
Expected return on plan assets	(13,005)	(15,516)	(14,249)
Amortization of prior service credit	(489)	(514)	(496)
Amortization of net loss	2,250	2,990	3,845
Other	850	910	0
Net periodic cost (benefit)	$ 4,022	$ 1,332	$ 3,852

EMPLOYEE BENEFIT PLANS - Weigh

EMPLOYEE BENEFIT PLANS - Weighted-average Assumptions (Details)	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Weighted-average assumptions used to determine projected benefit obligations
Discount rate	2.14%	3.21%
Rate of compensation increase	2.99%	3.23%
Weighted-average assumptions used to determine net periodic benefit cost
Discount rate	3.21%	2.82%	3.01%
Expected long-term return on plan assets	4.28%	5.18%	5.41%
Rate of compensation increase	3.23%	3.16%	3.25%

EMPLOYEE BENEFIT PLANS - Fair

EMPLOYEE BENEFIT PLANS - Fair Value of Company's Pension Plan Assets by Asset Category (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 357,181	$ 305,709	$ 304,325
Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,410	7,317
Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	91,998	72,237
Debt securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	129,965	21,247
Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	74,956	146,266
Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	56,852	58,642
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	57,165	183,701
Level 1 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,388	7,317
Level 1 | Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7,621	72,237
Level 1 | Debt securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	40,281	17,147
Level 1 | Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6,324	86,282
Level 1 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	551	718
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	298,502	120,367
Level 2 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,022	0
Level 2 | Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	84,377	0
Level 2 | Debt securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	89,684	4,100
Level 2 | Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	68,632	59,984
Level 2 | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	54,787	56,283
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,514	1,641
Level 3 | Cash and cash equivalents
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	$ 1,514	$ 1,641

EMPLOYEE BENEFIT PLANS - Estim

EMPLOYEE BENEFIT PLANS - Estimated Future Benefit Payments (Details) - Pension Plans $ in Thousands	Dec. 28, 2019USD ($)
Defined Benefit Plan Disclosure [Line Items]
2020	$ 111,848
2021	9,420
2022	10,344
2023	40,911
2024	10,814
2025-2029	$ 59,646

FOREIGN CURRENCY CONTRACTS - Sc

FOREIGN CURRENCY CONTRACTS - Schedule of Notional and Fair Value of Foreign Currency Contracts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018
Derivatives, Fair Value [Line Items]
Current Fiscal Year End Date	--12-28
Not Designated as Hedging Instrument | Other Current Liabilities | Foreign Exchange Forward
Derivatives, Fair Value [Line Items]
Notional Amount		$ 343,300
Fair Value		$ (1,319)
Not Designated as Hedging Instrument | Other Current Liabilities | Foreign Exchange Forward | Affiliated Entity
Derivatives, Fair Value [Line Items]
Notional Amount	$ 115,038
Fair Value	$ (876)

FOREIGN CURRENCY CONTRACTS - _2

FOREIGN CURRENCY CONTRACTS - Schedule of Derivative Instruments on Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Derivatives, Fair Value [Line Items]
Interest expense	$ 60,882	$ 63,772	$ 29,777
Other income, net	12,293	13,258	$ 37,760
Interest expense | Foreign Exchange Forward
Derivatives, Fair Value [Line Items]
Amount of gain (loss)	18,672	$ 1,486
Other income, net | Foreign Exchange Forward
Derivatives, Fair Value [Line Items]
Amount of gain (loss)	$ (121)

RESTRUCTURING AND ASSET IMPAI_3

RESTRUCTURING AND ASSET IMPAIRMENTS - Severance and Retention Costs By Classification on the Consolidated Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 13,839	$ 7,568	$ 4,778
Cost of services provided and products sold (excluding amortization of intangible assets)
Restructuring Cost and Reserve [Line Items]
Restructuring costs	6,715	950	2,873
Selling, general and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring costs	7,124	6,618	1,905
Severance and Transition Costs
Restructuring Cost and Reserve [Line Items]
Restructuring costs	11,454	7,520	3,849
Severance and Transition Costs | Cost of services provided and products sold (excluding amortization of intangible assets)
Restructuring Cost and Reserve [Line Items]
Restructuring costs	4,348	923	1,944
Severance and Transition Costs | Selling, general and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring costs	7,106	6,597	1,905
Asset Impairments and Other Costs
Restructuring Cost and Reserve [Line Items]
Restructuring costs	2,385	48	929
Asset Impairments and Other Costs | Cost of services provided and products sold (excluding amortization of intangible assets)
Restructuring Cost and Reserve [Line Items]
Restructuring costs	2,367	27	929
Asset Impairments and Other Costs | Selling, general and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 18	$ 21	$ 0

RESTRUCTURING AND ASSET IMPAI_4

RESTRUCTURING AND ASSET IMPAIRMENTS - Severance and Retention Costs by Reportable Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Segment Reporting Information [Line Items]
Restructuring costs	$ 13,839	$ 7,568	$ 4,778
Total reportable segments | RMS
Segment Reporting Information [Line Items]
Restructuring costs	3,110	0	291
Total reportable segments | DSA
Segment Reporting Information [Line Items]
Restructuring costs	7,307	1,063	1,604
Total reportable segments | Manufacturing
Segment Reporting Information [Line Items]
Restructuring costs	3,032	1,227	2,883
Unallocated corporate
Segment Reporting Information [Line Items]
Restructuring costs	$ 390	$ 5,278	$ 0

RESTRUCTURING AND ASSET IMPAI_5

RESTRUCTURING AND ASSET IMPAIRMENTS - Severance and Retention Costs For RMS Facility by Classification on the Consolidated Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 13,839	$ 7,568	$ 4,778
Cost of services provided and products sold (excluding amortization of intangible assets)
Restructuring Cost and Reserve [Line Items]
Restructuring costs	6,715	950	2,873
Selling, general and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring costs	7,124	6,618	1,905
Severance and Transition Costs
Restructuring Cost and Reserve [Line Items]
Restructuring costs	11,454	7,520	3,849
Severance and Transition Costs | Cost of services provided and products sold (excluding amortization of intangible assets)
Restructuring Cost and Reserve [Line Items]
Restructuring costs	4,348	923	1,944
Severance and Transition Costs | Selling, general and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring costs	7,106	6,597	1,905
Asset Impairments and Other Costs
Restructuring Cost and Reserve [Line Items]
Restructuring costs	2,385	48	929
Asset Impairments and Other Costs | Cost of services provided and products sold (excluding amortization of intangible assets)
Restructuring Cost and Reserve [Line Items]
Restructuring costs	2,367	27	929
Asset Impairments and Other Costs | Selling, general and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 18	21	0
2017 RMS Restructuring | RMS
Restructuring Cost and Reserve [Line Items]
Restructuring costs		1,983	18,145
2017 RMS Restructuring | RMS | Cost of services provided and products sold (excluding amortization of intangible assets)
Restructuring Cost and Reserve [Line Items]
Restructuring costs		1,669	18,078
2017 RMS Restructuring | RMS | Selling, general and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring costs		314	67
2017 RMS Restructuring | RMS | Severance and Transition Costs
Restructuring Cost and Reserve [Line Items]
Restructuring costs		1,161	429
2017 RMS Restructuring | RMS | Severance and Transition Costs | Cost of services provided and products sold (excluding amortization of intangible assets)
Restructuring Cost and Reserve [Line Items]
Restructuring costs		847	362
2017 RMS Restructuring | RMS | Severance and Transition Costs | Selling, general and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring costs		314	67
2017 RMS Restructuring | RMS | Asset Impairments and Other Costs
Restructuring Cost and Reserve [Line Items]
Restructuring costs		822	17,716
2017 RMS Restructuring | RMS | Asset Impairments and Other Costs | Cost of services provided and products sold (excluding amortization of intangible assets)
Restructuring Cost and Reserve [Line Items]
Restructuring costs		822	17,716
2017 RMS Restructuring | RMS | Asset Impairments and Other Costs | Selling, general and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring costs		$ 0	$ 0

RESTRUCTURING AND ASSET IMPAI_6

RESTRUCTURING AND ASSET IMPAIRMENTS - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 13,839	$ 7,568	$ 4,778
Severance and retention costs liability	6,406	2,921	6,856	$ 8,102
Asset Impairments and Other Costs
Restructuring Cost and Reserve [Line Items]
Restructuring costs	2,385	48	929
Severance and Transition Costs
Restructuring Cost and Reserve [Line Items]
Restructuring costs	11,454	7,520	3,849
Severance and Transition Costs | Accrued Compensation
Restructuring Cost and Reserve [Line Items]
Severance and retention costs liability	6,300	2,400
Severance and Transition Costs | Other Long-Term Liabilities
Restructuring Cost and Reserve [Line Items]
Severance and retention costs liability	100	500
Cost of revenue
Restructuring Cost and Reserve [Line Items]
Restructuring costs	6,715	950	2,873
Cost of revenue | Asset Impairments and Other Costs
Restructuring Cost and Reserve [Line Items]
Restructuring costs	2,367	27	929
Cost of revenue | Severance and Transition Costs
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 4,348	923	1,944
2017 RMS Restructuring | RMS
Restructuring Cost and Reserve [Line Items]
Restructuring costs		1,983	18,145
2017 RMS Restructuring | Asset Impairments and Other Costs | RMS
Restructuring Cost and Reserve [Line Items]
Restructuring costs		822	17,716
2017 RMS Restructuring | Severance and Transition Costs | RMS
Restructuring Cost and Reserve [Line Items]
Restructuring costs		1,161	429
2017 RMS Restructuring | Cost of revenue | RMS
Restructuring Cost and Reserve [Line Items]
Restructuring costs		1,669	18,078
2017 RMS Restructuring | Cost of revenue | Asset Impairments and Other Costs | RMS
Restructuring Cost and Reserve [Line Items]
Restructuring costs		822	17,716
2017 RMS Restructuring | Cost of revenue | Severance and Transition Costs | RMS
Restructuring Cost and Reserve [Line Items]
Restructuring costs		$ 847	$ 362

RESTRUCTURING AND ASSET IMPAI_7

RESTRUCTURING AND ASSET IMPAIRMENTS - Rollforward of Severance and Transition and Lease Obligation Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Restructuring Reserve [Roll Forward]
Beginning balance	$ 2,921	$ 6,856	$ 8,102
Expense	12,674	8,681	4,278
Payments / utilization	(9,206)	(12,341)	(6,103)
Foreign currency adjustments	17	(275)	579
Ending balance	$ 6,406	$ 2,921	$ 6,856

LEASES - Schedule of Cumulative

LEASES - Schedule of Cumulative Effect of Adoption of ASC 842 (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 30, 2018	Dec. 29, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Prepaid assets	$ 52,588	$ 49,034	$ 53,447
Property, plant and equipment, net	1,044,128	909,429	932,877
Operating lease right-of-use assets, net	140,085	134,172
Other assets	212,615	138,770	143,759
Other current liabilities	90,598	87,215	71,280
Operating lease right-of-use liabilities	116,252	111,570
Long-term debt, net and finance leases	$ 1,849,666	1,610,415	$ 1,636,598
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Prepaid assets		(4,413)
Property, plant and equipment, net		(23,448)
Operating lease right-of-use assets, net		134,172
Other assets		(4,989)
Other current liabilities		15,935
Operating lease right-of-use liabilities		111,570
Long-term debt, net and finance leases		$ (26,183)

LEASES - Additional Information

LEASES - Additional Information (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 30, 2018	Dec. 29, 2018
Lessor, Lease, Description [Line Items]
Derecognition of leased properties recorded in property, plant and equipment	$ (1,044,128)	$ (909,429)	$ (932,877)
Derecognition of other debt associated with leased properties	(1,849,666)	(1,610,415)	$ (1,636,598)
Future minimum lease payments for leases that have not yet commenced	$ 57,000
Minimum
Lessor, Lease, Description [Line Items]
Terms for leases that have not yet commenced	4 years
Maximum
Lessor, Lease, Description [Line Items]
Terms for leases that have not yet commenced	15 years
Accounting Standards Update 2016-02
Lessor, Lease, Description [Line Items]
Derecognition of leased properties recorded in property, plant and equipment		23,448
Derecognition of other debt associated with leased properties		26,183
Build-To-Suit Lease | Accounting Standards Update 2016-02
Lessor, Lease, Description [Line Items]
Derecognition of leased properties recorded in property, plant and equipment		26,000
Derecognition of other debt associated with leased properties		$ 26,000

LEASES - Right-of-Use Lease Ass

LEASES - Right-of-Use Lease Assets and Lease Liabilities in Condensed Consolidated Financial Statements (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 30, 2018
Leases [Abstract]
Operating lease right-of-use assets, net	$ 140,085	$ 134,172
Other current liabilities	20,357
Operating lease right-of-use liabilities	116,252	$ 111,570
Total operating lease liabilities	136,609
Property, plant and equipment, net	32,519
Current portion of long-term debt and finance leases	2,997
Long-term debt, net and finance leases	27,530
Total finance lease liabilities	$ 30,527

LEASES - Components of Operatin

LEASES - Components of Operating and Finance Lease Costs (Details) $ in Thousands	12 Months Ended
	Dec. 28, 2019USD ($)
Leases [Abstract]
Operating lease costs	$ 30,885
Amortization of right-of-use assets	4,007
Interest on lease liabilities	1,349
Short-term lease costs	1,056
Variable lease costs	3,161
Sublease income	(994)
Total lease costs	$ 39,464

LEASES - Supplemental Cash Flow

LEASES - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Cash flows included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 27,153
Operating cash flows from finance leases	1,406
Finance cash flows from finance leases	3,766
Non-cash leases activity:
Right-of-use lease assets obtained in exchange for new operating lease liabilities	24,382
Right-of-use lease assets obtained in exchange for new finance lease liabilities	$ 4,819	$ 1,473	$ 722

LEASES - Weighted Average Remai

LEASES - Weighted Average Remaining Lease Term and Discount Rates (Details)	Dec. 28, 2019
Weighted-average remaining lease term (in years)
Operating lease	8 years 2 months 23 days
Finance lease	12 years 11 months 19 days
Weighted-average discount rate
Operating lease	4.36%
Finance lease	4.58%

LEASES - Schedule of Future Min

LEASES - Schedule of Future Minimum Lease Payments Under Non-Cancellable Leases After Adoption (Details) $ in Thousands	Dec. 28, 2019USD ($)
Operating Leases, After Adoption of 842
2020	$ 25,955
2021	25,028
2022	20,614
2023	16,853
2024	16,007
Thereafter	60,371
Total minimum future lease payments	164,828
Less: Imputed interest	28,219
Total lease liabilities	136,609
Finance Leases, After Adoption of 842
2020	4,308
2021	3,832
2022	3,819
2023	2,929
2024	2,141
Thereafter	23,650
Total minimum future lease payments	40,679
Less: Imputed interest	10,152
Total lease liabilities	$ 30,527

LEASES - Schedule of Future M_2

LEASES - Schedule of Future Minimum Lease Payments, Non-Cancellable Operating Leases Before Adoption (Details) $ in Thousands	Dec. 28, 2019USD ($)
Operating Leases, Before Adoption of 842
2019	$ 25,411
2020	22,400
2021	21,544
2022	18,535
2023	15,398
Thereafter	66,870
Total minimum future lease payments	170,158
Finance Leases, Before Adoption of 842
2019	3,972
2020	3,759
2021	2,869
2022	2,967
2023	2,209
Thereafter	24,304
Total minimum future lease payments	40,080
Minimum future lease payments for leases that have not yet commenced	$ 14,000

COMMITMENTS AND CONTINGENCIES -

COMMITMENTS AND CONTINGENCIES - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 28, 2019USD ($)
Commitments and Contingencies Disclosure [Abstract]
Deductible amount under insurance policies	$ 1
Maximum insurance deductibles	5
Unconditional purchase obligations	$ 154

COMMITMENTS AND CONTINGENCIES_2

COMMITMENTS AND CONTINGENCIES - Schedule of Unconditional Purchase Obligations (Details) $ in Millions	Dec. 28, 2019USD ($)
Unconditional purchase obligations
Less than 1 Year	$ 106.1
1 - 3 Years	45
3 - 5 Years	2.9
Total	$ 154

SELECTED QUARTERLY FINANCIAL _3

SELECTED QUARTERLY FINANCIAL DATA (unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 691,138	$ 667,951	$ 657,568	$ 604,569	$ 601,530	$ 585,295	$ 585,301	$ 493,970	$ 2,621,226	$ 2,266,096	$ 1,857,601
Gross profit	262,314	246,116	238,104	211,777	226,417	216,200	215,981	181,469
Operating income	108,789	92,802	79,768	69,792	102,482	84,362	76,710	67,829	351,151	331,383	288,282
Net income attributable to common shareholders	$ 80,348	$ 72,810	$ 43,728	$ 55,133	$ 59,665	$ 60,368	$ 53,709	$ 52,631	$ 252,019	$ 226,373	$ 123,355
Basic:
Continuing operations attributable to common shareholders (in dollars per share)	$ 1.64	$ 1.49	$ 0.90	$ 1.14	$ 1.24	$ 1.25	$ 1.08	$ 1.10	$ 5.17	$ 4.69	$ 2.60
Discontinued operations (in dollars per share)	0	0	0	0	0	0	0.03	0	0	0.03	0
Net income attributable to common shareholders (in dollars per share)	1.64	1.49	0.90	1.14	1.24	1.25	1.11	1.10	5.17	4.72	2.60
Diluted:
Continuing operations attributable to common shareholders (in dollars per share)	1.61	1.46	0.88	1.11	1.21	1.22	1.06	1.08	5.07	4.59	2.54
Discontinued operations (in dollars per share)	0	0	0	0	0	0	0.03	0	0	0.03	0
Net income attributable to common shareholders (in dollars per share)	$ 1.61	$ 1.46	$ 0.88	$ 1.11	$ 1.21	$ 1.22	$ 1.10	$ 1.08	$ 5.07	$ 4.62	$ 2.54

Uncategorized Items - crl122820

Label	Element	Value
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ 1,424,000
Accounting Standards Update 2016-01 [Member] | Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	1,424,000
Accounting Standards Update 2016-01 [Member] | Total Equity Attributable to Common Shareholders [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ 1,424,000