Charles River Laboratories International (CRL) 10-Q 30 Oct 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	9 Months Ended	12 Months Ended
	Sep. 28, 2013	Dec. 28, 2013	Oct. 21, 2013
Document and Entity Information [Abstract]
Entity Registrant Name	CHARLES RIVER LABORATORIES INTERNATIONAL INC
Entity Central Index Key	1100682
Current Fiscal Year End Date		-16
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	28-Sep-13
Document Fiscal Year Focus		2013
Document Fiscal Period Focus	Q3
Amendment Flag	FALSE
Entity Common Stock, Shares Outstanding			48,117,860
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$2,300,514,887

CONDENSED_CONSOLIDATED_STATEME

CONDENSED CONSOLIDATED STATEMENTS OF INCOME (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
Net sales related to products	$116,732	$111,196	$364,877	$356,535
Net sales related to services	175,397	167,490	511,423	492,855
Net sales	292,129	278,686	876,300	849,390
Costs and expenses
Cost of products sold	70,294	63,649	202,954	190,629
Cost of services provided	121,909	121,778	366,639	357,705
Selling, general and administrative	54,903	51,047	167,021	156,924
Amortization of other intangibles	4,180	4,530	12,892	13,436
Operating income	40,843	37,682	126,794	130,696
Other income (expense)
Interest income	143	124	476	460
Interest expense	-2,319	-8,519	-18,143	-25,033
Other, net	4,059	-892	6,094	-2,582
Income from continuing operations, before income taxes	42,726	28,395	115,221	103,541
Provision (benefit) for income taxes	11,390	6,011	29,331	24,140
Income from continuing operations, net of income taxes	31,336	22,384	85,890	79,401
Income (loss) from discontinued operations, net of taxes	-113	-182	-1,183	-63
Net income	31,223	22,202	84,707	79,338
Less: Net income attributable to noncontrolling interests	-356	-230	-978	-459
Net income attributable to common shareowners	$30,867	$21,972	$83,729	$78,879
Basic:
Continuing operations attributable to common shareowners (in dollars per share)	$0.65	$0.47	$1.77	$1.64
Discontinued operations (in dollars per share)	$0	$0	($0.02)	$0
Net income attributable to common shareowners (in dollars per share)	$0.64	$0.46	$1.75	$1.64
Diluted:
Continuing operations attributable to common shareowners (in dollars per share)	$0.64	$0.46	$1.75	$1.63
Discontinued operations (in dollars per share)	$0	$0	($0.02)	$0
Net income attributable to common shareowners (in dollars per share)	$0.64	$0.46	$1.72	$1.63

CONDENSED_CONSOLIDATED_STATEME1

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
Net income	$31,223	$22,202	$84,707	$79,338
Foreign currency translation adjustment	16,371	12,962	-9,653	8,871
Unrealized gains (losses) on marketable securities:
Unrealized gains (losses) for the period	0	0	0	209
Less: reclassification adjustment for losses included in net income	0	0	0	712
Defined benefit plan gains (losses) and prior service costs not yet recognized as components of net periodic pension cost:
Amortization of prior service costs and net gains and losses	-752	-560	-2,249	-1,880
Comprehensive income, before tax	48,346	35,724	77,303	91,010
Income tax expense related to items of other comprehensive income	-326	156	874	701
Comprehensive income, net of tax	48,672	35,568	76,429	90,309
Less: comprehensive income related to noncontrolling interests	-454	-225	-1,260	-459
Comprehensive income attributable to common shareholders	$48,218	$35,343	$75,169	$89,850

CONDENSED_CONSOLIDATED_BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (USD $)	Sep. 28, 2013	Dec. 29, 2012
In Thousands, unless otherwise specified
Current assets
Cash and cash equivalents	$130,454	$109,685
Trade receivables, net	224,270	203,001
Inventories	87,146	88,470
Other current assets	105,153	83,601
Current assets of discontinued businesses	758	495
Total current assets	547,781	485,252
Property, plant and equipment, net	690,725	717,020
Goodwill	229,271	208,609
Other intangibles, net	87,245	84,922
Deferred tax asset	28,249	38,554
Other assets	57,170	48,659
Long-term assets of discontinued businesses	3,326	3,328
Total assets	1,643,767	1,586,344
Current liabilities
Current portion of long-term debt and capital leases	16,170	139,384
Accounts payable	29,675	31,218
Accrued compensation	57,414	46,951
Deferred revenue	55,357	56,422
Accrued liabilities	53,998	45,208
Other current liabilities	20,613	21,262
Current liabilities of discontinued businesses	1,944	1,802
Total current liabilities	235,171	342,247
Long-term debt and capital leases	624,310	527,136
Other long-term liabilities	101,724	104,966
Long-term liabilities of discontinued businesses	8,531	8,795
Total liabilities	969,736	983,144
Commitments and contingencies
Redeemable noncontrolling interest	14,577	0
Shareowners' equity
Preferred stock, $0.01 par value; 20,000,000 shares authorized; no shares issued and outstanding	0	0
Common stock, $0.01 par value; 120,000,000 shares authorized; 80,763,440 issued and 49,106,698 shares outstanding at March 30, 2013 and 79,607,981 issued and 48,220,037 shares outstanding at December 29, 2012	817	796
Capital in excess of par value	2,170,901	2,097,316
Accumulated deficit	-284,572	-368,301
Treasury stock, at cost, 31,656,742 shares and 31,387,944 shares at March 30, 2013 and December 29, 2012, respectively	-1,228,681	-1,135,609
Accumulated other comprehensive income	-1,957	6,603
Total shareowners' equity	656,508	600,805
Noncontrolling interests	2,946	2,395
Stockholder's Equity, Including Noncontrolling Interest and Redeemable Noncontrolling Interest	674,031	603,200
Total liabilities and equity	$1,643,767	$1,586,344

CONDENSED_CONSOLIDATED_BALANCE1

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Sep. 28, 2013	Dec. 29, 2012
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$0.01	$0.01
Preferred stock, shares authorized	20,000,000	20,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$0.01	$0.01
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	81,700,104,000	78,473,888,000
Common stock, shares outstanding	48,254,381,000	48,875,715,000
Treasury stock, shares	33,445,723,000	29,598,173,000

CONDENSED_CONSOLIDATED_STATEME2

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012
Cash flows relating to operating activities
Net income	$84,707	$79,338
Less: Income (loss) from discontinued operations	-1,183	-63
Income from continuing operations	85,890	79,401
Adjustments to reconcile net income from continuing operations to net cash provided by operating activities:
Depreciation and amortization	67,336	60,617
Amortization of debt issuance costs and discounts	9,124	13,136
Non-cash compensation	18,231	15,828
Deferred income taxes	8,675	-1,338
Other, net	-2,496	7,493
Changes in assets and liabilities:
Trade receivables	-22,663	-27,931
Inventories	1,445	-2,183
Other assets	-7,917	1,201
Accounts payable	-7,688	-6,743
Accrued compensation	10,500	6,287
Deferred revenue	-2,289	283
Accrued liabilities	3,285	-1,518
Taxes payable and prepaid taxes	-9,557	7,323
Other liabilities	-5,326	-8,177
Net cash provided by operating activities	146,550	143,679
Cash flows relating to investing activities
Payments to Acquire Businesses, Net of Cash Acquired	-24,218	-16,902
Capital expenditures	-25,319	-33,795
Purchases of investments	-15,341	-10,814
Proceeds from sale of investments	10,437	23,549
Other, net	108	2,746
Net cash used in investing activities	-54,333	-35,216
Cash flows relating to financing activities
Proceeds from long-term debt and revolving credit agreement	467,804	53,115
Proceeds from exercises of stock options and warrants	58,986	11,916
Payments on long-term debt, capital lease obligation and revolving credit agreement	-502,241	-112,731
Purchase of treasury stock	-91,703	-45,842
Other, net	-1,176	535
Net cash used in financing activities	-68,330	-93,007
Discontinued operations
Net cash used in operating activities	-1,533	-292
Net cash provided by discontinued operations	-1,533	-292
Effect of exchange rate changes on cash and cash equivalents	-1,585	-845
Net change in cash and cash equivalents	20,769	14,319
Cash and cash equivalents, beginning of period	109,685	68,905
Cash and cash equivalents, end of period	130,454	83,224
Supplemental cash flow information
Capitalized interest	$79	$472

CONDENSED_CONSOLIDATED_STATEME3

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (USD $)	Total	Accumulated (Deficit) Earnings	Accumulated Other Comprehensive Income	Common Stock	Capital in Excess of Par	Treasury Stock	Non-controlling Interest
In Thousands, unless otherwise specified
Balance at Dec. 29, 2012	$603,200	($368,301)	$6,603	$796	$2,097,316	($1,135,609)	$2,395
Components of comprehensive income, net of tax:
Net income	84,707	83,729					978
Other comprehensive income	-8,278		-8,560				282
Comprehensive income, net of tax	76,429						1,260
Noncontrolling Interest, Increase from Business Combination	8,963						8,963
Noncontrolling Interest, Change in Redemption Value					-4,905		4,905
Tax detriment associated with stock issued under employee compensation plans	1,362
Issuance of stock under employee compensation plans	58,918			21	58,897
Acquisition of treasury shares	-93,072				0	-93,072
Stock-based compensation	18,231				18,231
Stockholder's Equity, Including Noncontrolling Interest and Redeemable Noncontrolling Interest	674,031
Balance at Sep. 28, 2013		($284,572)	($1,957)	$817	$2,170,901	($1,228,681)	$17,523

Basis_of_Presentation

Basis of Presentation	9 Months Ended
	Sep. 28, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	BASIS OF PRESENTATION
	The condensed consolidated interim financial statements are unaudited, and certain information and footnote disclosures related thereto normally included in financial statements prepared in accordance with generally accepted accounting principles in the United States of America have been omitted in accordance with Rule 10-01 of Regulation S-X. In the opinion of management, the accompanying unaudited condensed consolidated financial statements were prepared following the same policies and procedures used in the preparation of the audited financial statements and reflect all adjustments (consisting of normal recurring adjustments) considered necessary to state fairly the financial position and results of operations of Charles River Laboratories International, Inc. The results of operations for the interim periods are not necessarily indicative of the results for the entire fiscal year. These condensed consolidated financial statements should be read in conjunction with our Annual Report on Form 10-K for the year ended December 29, 2012. Certain amounts in prior-year financial statements and related notes have been reclassified to conform with current period presentation.

Restructuring_Costs

Restructuring Costs	9 Months Ended
	Sep. 28, 2013
Restructuring and Related Activities [Abstract]
Restructuring and Contract Termination Costs	RESTRUCTURING COSTS
	Facilities
	In July 2013, management committed to a plan to consolidate production in its U.S. research model facilities and anticipates that these actions will result in the abandonment of certain long-lived assets, including a building at one of our facilities in California. During the quarter, the Company recorded to cost of sales accelerated depreciation of $6,766 related to the building based on its revised useful life. The Company anticipates that additional accelerated depreciation for the fourth quarter of 2013 will be up to approximately $7,000.
	Staffing Reductions
	We have implemented staffing reductions over the past few years to improve operating efficiency and profitability at various sites. As a result of these actions, for the nine months ended September 28, 2013 and September 29, 2012, we recorded severance and retention charges as shown below. As of September 28, 2013, $1,197 was included in accrued compensation and $1,413 in other long-term liabilities on our consolidated balance sheet.
	The following table rolls forward our severance and retention cost liability:
		Nine Months Ended
		September 28, 2013			September 29, 2012
	Balance, beginning of period	$	3,636		$	3,374
	Expense	1,058			1,881
	Payments/utilization	(2,084		)	(1,415		)
	Balance, end of period	$	2,610		$	3,840
	The following table presents severance and retention costs by classification on the income statement:
		Nine Months Ended
		September 28, 2013			September 29, 2012
	Severance charges included in cost of sales	$	989		$	936
	Severance charges included in selling, general and administrative expense	69			945
	Total expense	$	1,058		$	1,881
	The following table presents severance and retention cost by segment:
		Nine Months Ended
		September 28, 2013			September 29, 2012
	Research models and services	$	811		$	934
	Preclinical services	247			947
	Total expense	$	1,058		$	1,881

Supplemental_Balance_Sheet_Inf

Supplemental Balance Sheet Information	9 Months Ended
	Sep. 28, 2013
Supplemental Balance Sheet Information [Abstract]
Supplemental Balance Sheet Information	SUPPLEMENTAL BALANCE SHEET INFORMATION
	The composition of net trade receivables is as follows:
		28-Sep-13			29-Dec-12
	Client receivables	$	191,183		$	174,774
	Unbilled revenue	38,398			32,494
	Total	229,581			207,268
	Less allowance for doubtful accounts	(5,311		)	(4,267		)
	Net trade receivables	$	224,270		$	203,001
	The composition of inventories is as follows:
		September 28, 2013			December 29, 2012
	Raw materials and supplies	$	14,662		$	14,525
	Work in process	10,894			11,082
	Finished products	61,590			62,863
	Inventories	$	87,146		$	88,470
	The composition of other current assets is as follows:
		September 28, 2013			December 29, 2012
	Prepaid assets	$	28,860		$	20,404
	Deferred tax asset	29,832			30,018
	Marketable securities	11,084			6,781
	Prepaid income tax	35,148			26,169
	Restricted cash	229			229
	Other current assets	$	105,153		$	83,601
	The composition of net property, plant and equipment is as follows:
		September 28, 2013			December 29, 2012
	Land	$	40,638		$	40,812
	Buildings	704,262			697,547
	Machinery and equipment	373,431			356,960
	Leasehold improvements	36,907			34,916
	Furniture and fixtures	24,867			25,681
	Vehicles	4,028			3,736
	Computer hardware and software	111,025			107,171
	Construction in progress	33,396			46,186
	Total	1,328,554			1,313,009
	Less accumulated depreciation	(637,829		)	(595,989		)
	Net property, plant and equipment	$	690,725		$	717,020
	Depreciation is calculated for financial reporting purposes using the straight-line method based on the estimated useful lives of the assets. Depreciation expense for the nine months ended September 28, 2013 and September 29, 2012 was $54,444 and $47,181, respectively.
	The composition of other assets is as follows:
		September 28, 2013			December 29, 2012
	Deferred financing costs	$	7,563		$	6,424
	Cash surrender value of life insurance policies	25,625			26,071
	Equity-method affiliates	15,999			8,492
	Other assets	7,983			7,672
	Other assets	$	57,170		$	48,659
	The composition of other current liabilities is as follows:
		September 28, 2013			December 29, 2012
	Accrued income taxes	$	18,260		$	18,216
	Current deferred tax liability	469			410
	Accrued interest and other	1,884			2,636
	Other current liabilities	$	20,613		$	21,262
	The composition of other long-term liabilities is as follows:
		September 28, 2013			December 29, 2012
	Deferred tax liability	$	16,530		$	13,147
	Long-term pension liability	35,333			44,316
	Accrued Executive Supplemental Life Insurance Retirement Plan and Deferred Compensation Plan	28,518			26,663
	Other long-term liabilities	21,343			20,840
	Other long-term liabilities	$	101,724		$	104,966

Marketable_Securities_and_Equi

Marketable Securities and Equity-Method Affiliates	9 Months Ended
	Sep. 28, 2013
Marketable Securities and Equity-Method Affiliates [Abstract]
Marketable Securities and Equity-Method Affiliates	MARKETABLE SECURITIES AND EQUITY-METHOD AFFILIATES
	Marketable Securities
	Investments in marketable securities are reported at fair value and consist of time deposits. The carrying value for these time deposits approximates fair value. The amortized cost, gross unrealized gains, gross unrealized losses and fair value for marketable securities by major security type were as follows:
		September 28, 2013
		Amortized		Gross		Gross		Fair
		Cost		Unrealized		Unrealized		Value
				Gains		Losses
	Time deposits	$	11,084	$	—	$	—	$	11,084
		$	11,084	$	—	$	—	$	11,084
		December 29, 2012
		Amortized		Gross		Gross		Fair
		Cost		Unrealized		Unrealized		Value
				Gains		Losses
	Time deposits	$	6,781	$	—	$	—	$	6,781
		$	6,781	$	—	$	—	$	6,781
	Maturities of debt securities were as follows:
		September 28, 2013				December 29, 2012
		Amortized		Fair		Amortized		Fair
		Cost		Value		Cost		Value
	Due less than one year	$	11,084	$	11,084	$	6,781	$	6,781
	Due after one year through five years	—		—		—		—
	Due after ten years	—		—		—		—
		$	11,084	$	11,084	$	6,781	$	6,781
	Equity-Method Affiliates
	We have invested in two limited partnerships that are accounted for under the equity-method. In 2009, we entered into a limited partnership that invests in biotechnology and medical device companies. We committed $20,000, or approximately 12%, of the limited partnership's total committed capital. As of September 28, 2013, we have contributed $9,420 of our total committed capital of $20,000. During the first quarter of 2013, we entered into a second limited partnership that invests in technology and life sciences companies with an emphasis on early stage investments. We committed $10,000, or approximately 4% of the limited partnership's total committed capital. As of September 28, 2013, we have contributed $2,075 to the limited partnership.
	We recognized equity-method gains of $4,832 for the nine months ended September 28, 2013 related to these limited partnerships. These gains are reported within other income (expense). As of September 28, 2013, Equity Method Affiliates had a carrying value of $15,999, which is reported in Other Assets, Non-current, on the consolidated balance sheets.

Fair_Value

Fair Value	9 Months Ended
	Sep. 28, 2013
Fair Value Disclosures [Abstract]
Fair Value	FAIR VALUE
	Valuation methodologies used for assets and liabilities measured or disclosed at fair value are as follows:
	•	Time deposits—Valued at their ending balances as reported by the financial institutions that hold our securities, which approximates fair value.
	•	Life policies—Valued at cash surrender value based on fair value of underlying investments.
	•	Hedge contract—Valued at fair value by management based on our foreign exchange rates and forward points provided by banks.
	•	Redeemable noncontrolling interest—Valued using a weighted combination of a market-based approach, utilizing information about our company as well as publicly available industry information to determine revenue and earnings multiples, and an income approach based on estimated future cash flows based on projected financial data discounted by a weighted average cost of capital. Significant assumptions include a discount rate of 18% and a long-term pretax operating margin of 28% .
	Assets and liabilities measured at fair value on a recurring basis are summarized below:
		Fair Value Measurements at September 28, 2013
		Quoted Prices in Active Markets for Identical Assets Level 1		Significant Other Observable Inputs Level 2			Significant Unobservable Inputs Level 3		Assets and Liabilities at Fair Value
	Time deposits	$	—	$	11,084		$	—	$	11,084
	Life policies	—		18,893			—		18,893
	Total assets measured at fair value	$	—	$	29,977		$	—	$	29,977
	Redeemable noncontrolling interest	—		—			14,577		14,577
	Total liabilities measured at fair value	$	—	$	—		$	14,577	$	14,577
		Fair Value Measurements at December 29, 2012
		Quoted Prices in Active Markets for Identical Assets Level 1		Significant Other Observable Inputs Level 2			Significant Unobservable Inputs Level 3		Assets and Liabilities at Fair Value
	Time deposits	$	—	$	6,781		$	—	$	6,781
	Life policies	—		19,555			—		19,555
	Hedge contract	—		16			—		16
	Total assets measured at fair value	$	—	$	26,352		$	—	$	26,352
	Redeemable noncontrolling interest	—		—			—		—
	Total liabilities measured at fair value	$	—	$	—		$	—	$	—
	The book value of our term and revolving loans, which are variable rate loans carried at amortized cost, approximates fair value based current market pricing of similar debt.
		Fair Value Measurements
		Using Significant
		Unobservable Inputs
		(Level 3)
		Nine Months Ended
	Redeemable Noncontrolling Interest (Liability)	September 28, 2013		September 29, 2012
	Beginning balance	$	—	$	—
	Transfers in and/or out of Level 3	—		—
	Total gains or losses (realized/unrealized):
	Included in other income (expense)	476		—
	Included in other comprehensive income (CTA)	233		—
	Included in additional paid-in capital	4,905
	Purchases, issuances and settlements	8,963		—
	Ending balance	$	14,577	$	—
		Fair Value Measurements
		Using Significant
		Unobservable Inputs
		(Level 3)
		Nine Months Ended
	Auction rate securities (Asset)	September 28, 2013		September 29, 2012
	Beginning balance	$	—	$	11,051
	Transfers in and/or out of Level 3	—		—
	Total gains or losses (realized/unrealized):
	Included in other income (expense)	—		(712		)
	Included in other comprehensive income	—		921
	Purchases, issuances and settlements	—		(11,260		)
	Ending balance	$	—	$	—
	We enter into derivative instruments to hedge foreign currency exchange risk to reduce the impact of changes to foreign currency rates on our financial statements. During the nine months ended September 28, 2013, we recognized $289 of net hedge losses associated with forward currency contracts open during the period. As of September 28, 2013, there were no open forward currency contracts.

Goodwill_and_Other_Intangible_

Goodwill and Other Intangible Assets	9 Months Ended
	Sep. 28, 2013
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	GOODWILL AND OTHER INTANGIBLE ASSETS
	The following table displays the gross carrying amount and accumulated amortization of definite-lived intangible assets by major class:
		September 28, 2013							December 29, 2012
		Gross Carrying Amount				Accumulated Amortization & Impairment Loss			Gross Carrying Amount			Accumulated Amortization & Impairment Loss
	Backlog	$	2,899			$	(2,469	)	$	2,875		$	(2,375	)
	Client relationships	313,595				(238,245		)	305,178			(231,902		)
	Client contracts	15,339				(15,339		)	15,366			(15,366		)
	Trademarks and trade names	5,380				(4,949		)	5,326			(4,821		)
	Standard operating procedures	2,753				(1,339		)	2,751			(863		)
	Other identifiable intangible assets	10,384				(4,202		)	10,033			(4,718		)
	Total other intangible assets	$	350,350			$	(266,543	)	$	341,529		$	(260,045	)
	Additionally, as of both September 28, 2013 and December 29, 2012 , other intangible assets, net, included $3,438 of indefinite-lived intangible assets.
	The changes in the gross carrying amount and accumulated impairment loss of goodwill are as follows:
							Adjustments to Goodwill
			29-Dec-12				Acquisitions			Foreign Exchange			28-Sep-13
	Research Models and Services
	Gross carrying amount		$	63,139			$	19,273		$	361		$	82,773
	Preclinical Services
	Gross carrying amount		1,150,470				—			1,028			1,151,498
	Accumulated impairment loss		(1,005,000		)								(1,005,000		)
	Total
	Gross carrying amount		$	1,213,609			$	19,273		$	1,389		$	1,234,271
	Accumulated impairment loss		(1,005,000		)								(1,005,000		)
	Goodwill, net		$	208,609									$	229,271

LongTerm_Debt_and_Capital_Leas

Long-Term Debt and Capital Lease Obligations	9 Months Ended
	Sep. 28, 2013
Debt Disclosure [Abstract]
Long-Term Debt and Capital Lease Obligations	LONG-TERM DEBT AND CAPITAL LEASE OBLIGATIONS
	Long-Term Debt
	Long-term debt consists of the following:
		September 28, 2013			December 29, 2012
	2.25% Senior convertible debentures:
	Principal	$	—		$	349,995
	Unamortized debt discount	—			(6,726		)
	Net carrying amount of senior convertible debentures	—			343,269
	Term loan facilities	414,750			290,947
	Revolving credit facility	224,752			32,000
	Other long-term debt	237			232
	Total debt	639,739			666,448
	Less: current portion of long-term debt	(15,987		)	(139,373		)
	Long-term debt	$	623,752		$	527,075
	On May 29, 2013, we amended and restated our credit agreement dated September 23, 2011 to repay loans outstanding under the previous agreement, to retire our 2.25% Senior Convertible Debentures (2013 Notes), and to extend the maturity date of our credit agreement under a new $970,000 agreement (the $970M Credit Facility). The $970M Credit Facility provides for a $420,000 U.S. term loan facility and a $550,000 multi-currency revolving credit facility. The revolving credit facility may be drawn in U.S. Dollars, Euros, Pound Sterling, or Japanese Yen, subject to sub-limits by currency. Under specified circumstances, we have the ability to expand the term loan and/or revolving credit facility by up to $350,000 in the aggregate. Certain financing costs associated with the $970M Credit Facility were capitalized as deferred financing costs and will be amortized over the life of the agreement using the effective interest method. As a result of the refinancing and the associated modification and extinguishment of the previous debt agreement, we recognized an extinguishment loss of $389 of deferred financing costs associated with the previous credit agreement.
	The $420,000 U.S. term loan matures in quarterly installments through maturity on May 29, 2018. The revolving credit facility also matures on May 29, 2018 and requires no scheduled payment before this date. The interest rates applicable to the $970M Credit Facility are variable and are based on an applicable rate plus a spread determined by our leverage ratio. As of September 28, 2013, the interest rate spread for the adjusted LIBOR was 1.25%.
	The $970M Credit Facility includes certain customary representations and warranties, events of default, notices of material adverse changes to our business and negative and affirmative covenants. As of September 28, 2013, we were compliant with all financial covenants specified in the credit agreement.
	We had $4,855 outstanding under letters of credit as of September 28, 2013.
	Our $350,000 2013 Notes issued in June 2006 became due in June 2013 and were retired with funds provided by the $970M Credit Facility and available cash.
	Principal maturities of existing debt for the periods set forth in the table below, are as follows:
	Twelve Months Ending
	Sep-14	$	15,987
	Sep-15	42,000
	Sep-16	42,000
	Sep-17	63,000
	Sep-18	476,752
	Total	$	639,739
	We have capital leases for equipment. These leases are capitalized using interest rates considered appropriate at the inception of the lease. Capital lease obligations amounted to $741 and $72 at September 28, 2013 and December 29, 2012, respectively.

Equity

Equity	9 Months Ended
	Sep. 28, 2013
Stockholders' Equity Note [Abstract]
Equity	EQUITY
	Earnings Per Share
	Basic earnings per share for the three and nine months ended September 28, 2013 and September 29, 2012 was computed by dividing earnings available to common shareholders for these periods by the weighted average number of common shares outstanding in the respective periods adjusted for contingently issuable shares. The weighted average number of common shares outstanding for the three and nine months ended September 28, 2013 and September 29, 2012 have been adjusted to include common stock equivalents for the purpose of calculating diluted earnings per share for these periods.
	Options to purchase 2,652,660 shares and 4,667,739 shares were outstanding in each of the three months ended September 28, 2013 and September 29, 2012, respectively, but were not included in computing diluted earnings per share because their inclusion would have been anti-dilutive. Basic weighted average shares outstanding for the three and nine months ended September 28, 2013 and September 29, 2012 excluded the weighted average impact of 1,107,313 and 941,873 shares, respectively, of non-vested restricted stock awards. Options to purchase 2,363,878 shares and 4,590,418 shares were outstanding in each of the nine months ended September 28, 2013 and September 29, 2012, respectively, but were not included in computing diluted earnings per share because their inclusion would have been anti-dilutive.
	The following table illustrates the reconciliation of the numerator and denominator in the computations of the basic and diluted earnings per share:
		Three Months Ended						Nine Months Ended
		September 28, 2013			September 29, 2012			September 28, 2013			September 29, 2012
	Numerator:
	Income from continuing operations for purposes of calculating earnings per share	$	30,980		$	22,154		$	84,912		$	78,942
	Income (loss) from discontinued businesses	(113		)	$	(182	)	$	(1,183	)	$	(63	)
	Denominator:
	Weighted-average shares outstanding—Basic	47,910,649			47,625,806			47,950,018			48,028,602
	Effect of dilutive securities:
	2.25% senior convertible debentures	—			—			—			—
	Stock options and contingently issued restricted stock	530,516			482,808			704,118			447,544
	Weighted-average shares outstanding—Diluted	48,441,165			48,108,614			48,654,136			48,476,146
	Basic earnings per share from continuing operations attributable to common shareholders	$	0.65		$	0.47		$	1.77		$	1.64
	Basic earnings (loss) per share from discontinued operations attributable to common shareholders	$	—		$	—		$	(0.02	)	$	—
	Diluted earnings per share from continuing operations attributable to common shareholders	$	0.64		$	0.46		$	1.75		$	1.63
	Diluted earnings (loss) per share from discontinued operations attributable to common shareholders	$	—		$	—		$	(0.02	)	$	—
	Treasury Shares
	For the nine months ended September 28, 2013 and September 29, 2012, we repurchased 1,945,021 shares of common stock for $88,553 and 1,222,432 shares of common stock for $42,800, respectively, through open market purchases made in reliance on Rules 10b5-1 and 10b-18 of the Securities Exchange Act of 1934, as amended. Additionally, our 2007 Incentive Plan permits the netting of common stock upon vesting of restricted stock awards in order to satisfy individual tax withholding requirements. During the nine months ended September 28, 2013 and September 29, 2012, we acquired 112,748 shares for $4,519 and 84,086 shares for $3,042, respectively, as a result of such withholdings.
	Share repurchases for the nine months ended September 28, 2013 and September 29, 2012 were as follows:
		Nine Months Ended
		September 28, 2013			September 29, 2012
	Number of shares of common stock repurchased	2,057,769			1,306,518
	Total cost of repurchase	$	93,072		$	45,842
	On July 30, 2013, our Board of Directors increased the stock repurchase authorization to $850,000 from $750,000.
	Warrants
	Separately and concurrently with the pricing of our 2013 Notes in 2006, we issued warrants for approximately 7.2 million shares of common stock. The warrants give the holders the right to receive, for no additional consideration, cash or shares (at the Company's option) with a value equal to the appreciation in the price of the Company's shares above $59.93. The warrants expire over 90 equal installments between September 13, 2013 and January 22, 2014. As of September 28, 2013, approximately 6.3 million are outstanding.

Income_Taxes

Income Taxes	9 Months Ended
	Sep. 28, 2013
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES
	The following table provides a reconciliation of the provision for income taxes on the condensed consolidated statements of income:
		Three Months Ended						Nine Months Ended
		September 28, 2013			September 29, 2012			September 28, 2013			September 29, 2012
	Income from continuing operations before income taxes	$	42,726		$	28,395		$	115,221		$	103,541
	Effective tax rate	26.7		%	21.2		%	25.5		%	23.3		%
	Provision for income taxes	$	11,390		$	6,011		$	29,331		$	24,140
	Our overall effective tax rate was 26.7% in the third quarter of 2013 and 21.2% in the third quarter of 2012. The increase was primarily attributable to a $2,006 reduction of a tax asset related to the ongoing transfer pricing controversy with the Canadian Revenue Authority (CRA), a reduction in benefits from the U.K. research and development enhanced deduction regime due to the early adoption of the new refundable research and development credit that was enacted in the third quarter of 2013, and a French tax law change enacted in the first quarter of 2013 that limits the deductibility of interest by our French affiliates. These tax costs were partially offset in the third quarter of 2013 by a favorable mix of earnings, increased benefits from Canadian Scientific Research and Experimental Development credits (SR&ED), and an increased tax benefit from the U.S. domestic production deduction. The effective tax rate for the third quarter of 2012 reflects a tax benefit of $1,226 related to the settlement of a Canadian tax controversy for the SR&ED credits claimed in 2003 and 2004.
	The effective tax rate for the nine months ended September 28, 2013 reflects the items noted above as well as a discrete tax cost of $703 due to the retroactive impact of the French tax law change to 2012, a $525 discrete tax cost related to nondeductible transaction costs incurred in 2012 for the acquisition of Vital River, which closed in the first quarter of 2013, and a discrete tax benefit of $330 for the retroactive impact to 2012 of a change in U.S. Federal tax law enacted during the first quarter of 2013 related to the U.S. anti deferral regime. Additionally the effective tax rate for the nine months ended September 29, 2012 reflects an unbenefitted capital loss of $712 on the sale of auction rate securities recorded in the first quarter of 2012.
	In accordance with Canadian Federal tax law, we claim SR&ED credits on qualified research and development costs incurred by our preclinical services facility in Canada in the performance of projects for non-Canadian clients. Additionally, in accordance with the tax law of the United Kingdom, we claim enhanced deductions related to qualified research and development costs incurred by our preclinical services facility in Scotland, in the performance of certain client contracts. On July 17, 2013, the U.K. government enacted a tax law change that replaces the existing research and development enhanced deduction with a research and development credit. In the third quarter of 2013 we elected to adopt the tax law change with retroactive application to April 1, 2013. The benefit of the new refundable credit for the period April 1, 2013 through September 28, 2013 of $1,714 is reported in Cost of Services Provided in our Condensed Consolidated Statements of Income.
	During the third quarter of 2013, our unrecognized tax benefits recorded decreased by $13,325 to $18,782 due primarily to a settlement reached during the quarter with the CRA related to SR&ED credits claimed in 2005 through 2011. This reduction was partially offset with an increase from ongoing evaluation of uncertain tax positions in the current and prior periods and foreign exchange movement. The amount of unrecognized income tax benefits that would impact the effective tax rate favorably decreased by $8,628 to $17,268. The decrease was due primarily to the Canadian SR&ED settlement. The amount of accrued interest on unrecognized tax benefits decreased by $1,788 to $637 in the third quarter of 2013 primarily due to the Canadian SR&ED settlement. It is reasonably possible as of September 28, 2013 that the liability for unrecognized tax benefits for the uncertain tax position associated with an acquisition agreement termination fee could decrease within the next twelve months by approximately $11,000 due to the potential expiration of a statute of limitations.
	We conduct business in a number of tax jurisdictions. As a result, we are subject to tax audits in jurisdictions including, but not limited to, the United States, the United Kingdom, Japan, France, Germany and Canada. With few exceptions, we are no longer subject to U.S. and international income tax examinations for years before 2006.
	We are currently under audit by the CRA for the years 2006 through 2009. In the fourth quarter of 2012, we received a draft reassessment from the CRA related to the transfer pricing in our preclinical services operations in Montreal. We received revised draft reassessments in the second quarter of 2013. The CRA proposes to disallow certain deductions related to headquarter service charges for the years 2006 through 2009. We intend to file an objection with the CRA upon receipt of the Notice of Reassessment and apply to the Internal Revenue Service (IRS) and the CRA for relief pursuant to the competent authority procedure provided in the tax treaty between the U.S. and Canada. We believe that the controversy will likely be settled via the competent authority process. In the fourth quarter of 2012, we established a reserve for this uncertain tax position of $2,408 related to years 2006 through 2012 to reduce the tax benefit recognized for these deductions in Canada to the level that we believe will likely be realized upon the ultimate resolution of this controversy. Additionally, in the fourth quarter of 2012, we recognized a tax asset of $2,981, which is included in Other Assets, that represents the correlative relief that we believe would more likely than not be received in the U.S. via the competent authority process. In the third quarter of 2013 there was a U.S. tax court opinion issued that could impact our ability to recognize the full benefit of the correlative relief recorded in 2012. As a result, in the third quarter of 2013, the U.S. tax asset recorded in the fourth quarter of 2012 was reduced by $2,006 to $975. The actual amounts of the liability for Canadian taxes and the asset for the correlative relief in the U.S. could be different based upon the agreement reached between the IRS and CRA.
	On October 9, 2013 we were notified by the German Tax Office of an upcoming audit of our German operations for years 2008 through 2011. We do not believe that resolution of this audit will have a material impact on our financial position or results of operations.
	We believe we have appropriately provided for all uncertain tax positions.
	In the third quarter of 2013 the French government proposed a change to French tax law that, if enacted, could further reduce the deductibility of interest by our French affiliates in 2013 and beyond. We are currently analyzing the potential impact of the proposed law change.
	In accordance with our policy, the undistributed earnings of our non-U.S. subsidiaries remain indefinitely reinvested as of the end of the third quarter of 2013 as they are required to fund needs outside the U.S. and cannot be repatriated in a manner that is substantially tax free.
	The income tax expense (benefit) related to items of other comprehensive income are as follows:
		Three Months Ended						Nine Months Ended
		September 28, 2013			September 29, 2012			September 28, 2013			September 29, 2012
	Income tax expense (benefit) related to foreign currency translation adjustment	$	(615	)	$	(60	)	$	42		$	(98	)
	Income tax expense related to change in unrecognized pension gains, losses and prior service costs	289			216			832			799
	Income tax expense (benefit) related to items of other comprehensive income	$	(326	)	$	156		$	874		$	701

Employee_Benefits

Employee Benefits	9 Months Ended
	Sep. 28, 2013
Compensation and Retirement Disclosure [Abstract]
Employee Benefits	EMPLOYEE BENEFITS
	The following table provides the components of net periodic benefit cost for our defined benefit plans for the three month period ended:
		Pension Benefits						Supplemental
								Retirement Benefits
		September 28, 2013			September 29, 2012			September 28, 2013		September 29, 2012
	Service cost	$	822		$	922		$	160	$	160
	Interest cost	2,762			2,824			177		223
	Expected return on plan assets	(3,593		)	(3,459		)	—		—
	Amortization of prior service cost (credit)	(147		)	(256		)	165		165
	Amortization of net loss (gain)	671			586			63		65
	Net periodic benefit cost	$	515		$	617		$	565	$	613
	The following table provides the components of net periodic benefit cost for our defined benefit plans for the nine month period ended:
		Pension Benefits						Supplemental
								Retirement Benefits
		September 28, 2013			September 29, 2012			September 28, 2013		September 29, 2012
	Service cost	$	2,492		$	2,880		$	482	$	480
	Interest cost	8,334			8,445			531		669
	Expected return on plan assets	(10,842		)	(10,319		)	—		—
	Amortization of prior service cost (credit)	(444		)	(566		)	495		495
	Amortization of net loss (gain)	2,043			1,756			189		195
	Net periodic benefit cost	$	1,583		$	2,196		$	1,697	$	1,839
	During 2013, we expect to contribute $9,686 to our pension plans.

Stock_Plans_and_StockBased_Com

Stock Plans and Stock-Based Compensation	9 Months Ended
	Sep. 28, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Plans and Stock Based Compensation	STOCK PLANS AND STOCK-BASED COMPENSATION
	The estimated fair value of our stock-based awards, less expected forfeitures, is amortized over the awards' vesting period on a straight-line basis. The following table presents stock-based compensation included in our consolidated statement of income:
		Three Months Ended								Nine Months Ended
		September 28, 2013				September 29, 2012				September 28, 2013			September 29, 2012
	Stock-based compensation expense included in:
	Cost of sales	$	1,332			$	1,271			$	4,051		$	3,995
	Selling, general and administration	4,715				3,970				14,181			11,833
	Stock-based compensation, before income taxes	6,047				5,241				18,232			15,828
	Provision for income taxes	(2,103		)		(1,847		)		(6,422		)	(5,615		)
	Stock-based compensation, net of tax	$	3,944			$	3,394			$	11,810		$	10,213
	The fair value of stock-based awards granted during the first nine months of 2013 and 2012 was estimated on the grant date using the Black-Scholes option-pricing model with the following weighted-average assumptions:
		September 28, 2013				September 29, 2012
	Expected life (in years)	4.2 years				4.5 years
	Expected volatility	32.7		%		34.9		%
	Risk-free interest rate	0.8		%		0.84		%
	Expected dividend yield	0		%		0		%
	Weighted-average grant date fair value	$	11.17			$	10.94
	Stock Options
	The following table summarizes stock option activities under our plans:
		Shares			Weighted Average				Weighted Average		Aggregate
					Exercise Price				Remaining		Intrinsic
									Contractual Life		Value
									(in years)
	Options outstanding as of December 29, 2012	5,860,403			$	39.11
	Options granted	593,499			$	40.54
	Options exercised	(1,729,768	)		$	34.06
	Options canceled	(105,040	)		$	45.68
	Options outstanding as of September 28, 2013	4,619,094			$	41.04			3.25 years		$	30,997
	Options exercisable as of September 28, 2013	3,022,605			$	42.52			2.00 years		$	18,186
	As of September 28, 2013, the unrecognized compensation cost related to 1,596,489 unvested stock options expected to vest was $12,634. This unrecognized compensation will be recognized over an estimated weighted-average amortization period of 2.5 years.
	The total intrinsic value of options exercised during the nine months ended September 28, 2013 and September 29, 2012 was $17,629 and $2,769, respectively, with intrinsic value defined as the difference between the market price on the date of exercise and the grant date price. The total amount of cash received from the exercise of options during the nine months ended September 28, 2013 and September 29, 2012 was $58,986 and $12,304, respectively. The actual tax benefit realized for the tax deductions from option exercises totaled $6,436 for the nine months ended September 28, 2013. A charge of $1,362 was recorded in capital in excess of par value in the first nine months of 2013 for the excess of deferred tax assets over the actual tax benefits at option exercise. We settle stock option exercises with newly issued common shares.
	Restricted Stock
	Stock compensation expense associated with restricted common stock is charged for the market value on the date of grant, less estimated forfeitures, and is amortized over the awards' vesting period on a straight-line basis.
	The following table summarizes the restricted stock activity for the nine months ended September 28, 2013:
		Restricted Stock			Weighted
					Average
					Grant Date
					Fair Value
	Outstanding as of December 29, 2012	934,505			$	35.83
	Granted	565,699			40.52
	Vested	(371,458	)		40.37
	Canceled	(21,433	)		43.75
	Outstanding as of September 28, 2013	1,107,313			$	36.55
	As of September 28, 2013, the unrecognized compensation cost related to shares of unvested restricted stock expected to vest was $32,752. This unrecognized compensation will be recognized over an estimated weighted-average amortization period of 31.5 months. The total fair value of restricted stock grants that vested during the nine months ended September 28, 2013 and September 29, 2012 was $14,996 and $10,297, respectively. The actual tax benefit realized for the tax deductions from restricted stock grants that vested totaled $5,375 for the nine months ended September 28, 2013.
	Performance Based Stock Award Program
	On February 22, 2013, we granted 163,847 Performance Share Units (PSUs) to certain executive officers. The PSUs will be paid out in our common stock based upon the results of two metrics: (1) performance based on our earnings per share with certain defined adjustments and (2) our relative stock price market performance based on a 3-year relative Total Shareholder Return calculation. Accordingly, the actual total number of our shares into which the granted PSUs will convert can range from no shares to 327,694 shares. The PSUs will be fully vested in December 2015 and will be paid out in the form of our common stock in the first quarter of 2016. Compensation expense associated with the PSUs of $1,455 was recorded during the nine months ended September 28, 2013.

Commitments_and_Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 28, 2013
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES
	Various lawsuits, claims and proceedings of a nature considered normal to our business are pending against us. In the opinion of management, the outcome of such proceedings and litigation currently pending will not materially affect our consolidated financial statements.
	In early May 2013, the Company commenced an investigation into inaccurate billing with respect to certain government contracts.  The Company promptly reported these matters to the relevant government contracting officers, the Department of Health and Human Services' Office of the Inspector General, and the Department of Justice, and we are cooperating with these agencies to ensure the proper repayment and resolution of this matter. The Company identified approximately $1,500 in excess amounts billed on these contracts since January 1, 2007 and reserved such amount.  Because of the preliminary stage of discussions with the government and complex nature of this matter, the Company believes that it is reasonably possible that additional losses may be incurred. However, the Company cannot at this time estimate the potential range of loss beyond the current reserve of $1,500.
	On July 27, 2012, a Mauritius supplier of large animal models submitted an Application for Arbitration with The Permanent Secretariat, The Permanent Court of Arbitration, The Mauritius Chamber of Commerce and Industry in Port Louis, Mauritius.  The supplier asserted that the Company failed to pay certain invoices and the supplier was therefore permitted to terminate the supply agreement.  The Company filed a counterclaim asserting that the supplier had failed to meet its contractual obligations under the supply agreement.  The arbitration hearing relating to this contract dispute took place in Mauritius from August 13-15, 2013. While no prediction may be made as to the outcome of arbitration, the Company intends to defend against this proceeding vigorously and therefore an estimate of the possible loss or range of loss cannot be made.

Business_Segment_Information

Business Segment Information	3 Months Ended
	Sep. 28, 2013
Segment Reporting [Abstract]
Business Segment Information	BUSINESS SEGMENT INFORMATION
	We report two business segments, Research Models and Services (RMS) and Preclinical Services (PCS). Our RMS segment includes sales of Research Models, Genetically Engineered Models and Services (GEMS), Insourcing Solutions (IS), Research Animal Diagnostic Services (RADS), Discovery Research Services (DRS), Endotoxin and Microbial Detection (EMD) products and services, and Avian Vaccine products and services. Our PCS segment includes services required to take a drug through the development process, which includes discovery services, safety assessment and biopharmaceutical services.
	The following table presents sales and other financial information by business segment.
		Three Months Ended						Nine Months Ended
		September 28, 2013			September 29, 2012			September 28, 2013			September 29, 2012
	Research Models and Services
	Net sales	$	173,405		$	166,484		$	534,867		$	523,247
	Gross margin	65,710			65,902			221,916			224,364
	Operating income	40,260			43,389			145,193			158,398
	Depreciation and amortization	16,876			9,670			37,378			27,697
	Capital expenditures	6,110			7,423			16,464			27,892
	Preclinical Services
	Net sales	$	118,724		$	112,202		$	341,433		$	326,143
	Gross margin	34,216			27,358			84,791			76,693
	Operating income	18,636			10,975			37,631			25,958
	Depreciation and amortization	10,039			10,880			29,957			32,920
	Capital expenditures	2,986			2,819			8,855			5,903
	A reconciliation of segment operating income to consolidated operating income is as follows:
		Three Months Ended						Nine Months Ended
		September 28, 2013			September 29, 2012			September 28, 2013			September 29, 2012
	Total segment operating income	$	58,896		$	54,364		$	182,824		$	184,356
	Unallocated corporate overhead	(18,053		)	(16,682		)	(56,030		)	(53,660		)
	Consolidated operating income	$	40,843		$	37,682		$	126,794		$	130,696
	Net sales for each significant service area are as follows:
		Three Months Ended						Nine Months Ended
		September 28, 2013			September 29, 2012			September 28, 2013			September 29, 2012
	Research models	$	92,969		$	90,877		$	294,993		$	293,575
	Research model services	52,105			53,400			156,661			163,247
	EMD	28,331			22,207			83,213			66,425
	Total research models and services	173,405			166,484			534,867			523,247
	Total preclinical services	118,724			112,202			341,433			326,143
	Total sales	$	292,129		$	278,686		$	876,300		$	849,390
	A summary of unallocated corporate overhead consists of the following:
		Three Months Ended						Nine Months Ended
		September 28, 2013			September 29, 2012			September 28, 2013			September 29, 2012
	Stock-based compensation expense	$	3,260		$	2,827		$	9,927		$	8,512
	U.S. retirement plans	1,275			1,276			3,617			3,662
	Audit, tax and related expense	811			842			3,135			2,133
	Salary and bonus	5,831			4,813			16,057			14,602
	Global IT	3,002			3,285			8,448			9,501
	Employee health, long-term disability and fringe benefit expense	(1,470		)	(2,248		)	(898		)	(1,395		)
	Consulting and professional services	1,439			1,061			3,443			3,581
	Depreciation expense	1,570			1,554			4,712			4,693
	Other general unallocated corporate expenses	2,335			3,272			7,589			8,371
	Total unallocated corporate overhead costs	$	18,053		$	16,682		$	56,030		$	53,660
	Other general unallocated corporate expenses consist of various departmental costs including those associated with senior executives, corporate accounting, legal, tax, human resources and treasury.

Discontinued_Operations

Discontinued Operations	9 Months Ended
	Sep. 28, 2013
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	DISCONTINUED OPERATIONS
	On March 28, 2011, we disposed of our Phase I clinical business for a nominal amount. As part of the disposition we remained the guarantor of the Phase I facility lease. During the second quarter of 2011, we recognized the value of the guarantee net of the buyer's related indemnity as a liability of $2,994, which we are accreting ratably over the remaining term of the lease. The facility lease runs through January 2021 with remaining lease payments totaling $11,677 as of September 28, 2013.
	During the period ended December 29, 2012, we concluded that the decreasing financial viability of the lessee (the buyer of the Phase I clinical business) increased the probability that we will be required to make future lease payments as guarantor. As a result, we recorded an additional contingent loss for the guarantee, reflecting our estimate of the total future lease payments, which include real estate taxes passed on by the lessor, less estimated sublease income. Under the terms of the lease, if we were required to honor the guarantee due to default by the lessee, we had the right to obtain control of the leased property.
	On April 4, 2013, the buyer of our Phase I clinical business filed for Chapter 11 bankruptcy. As a result, we revised our estimate of the total future lease payments, less estimated sublease income, resulting in an additional charge of $1,316. In July 2013, the bankruptcy court approved the rejection of the lease, and effective July 1, 2013, we assumed control of the leased property and assumed obligations under the lease consistent with the guarantee. The total carrying amount of the liability for our obligation under the lease as of September 28, 2013 is $10,375 and is reflected on the consolidated balance sheet as a liability of discontinued operations.
	The consolidated financial statements classify, as discontinued operations, the assets and liabilities, operating results and cash flows, of businesses that are discontinued for all periods presented. Operating results from discontinued operations are as follows:
		Three Months Ended						Nine Months Ended
		September 28, 2013			September 29, 2012			September 28, 2013			September 29, 2012
	Net sales	$	—		$	—		$	—		$	—
	Income (loss) from operations of discontinued businesses, before income taxes	(172		)	49			(1,894		)	221
	Provision (benefit) for income taxes	(59		)	231			(711		)	284
	Income (loss) from operations of discontinued businesses, net of taxes	$	(113	)	$	(182	)	$	(1,183	)	$	(63	)
	Assets and liabilities of discontinued operations at September 28, 2013 and December 29, 2012 consisted of the following:
		September 28,			December 29,
		2013			2012
	Current assets	$	758		$	495
	Long-term assets	3,326			3,328
	Total assets	$	4,084		$	3,823
	Current liabilities	$	1,944		$	1,802
	Long-term liabilities	8,531			8,795
	Total liabilities	$	10,475		$	10,597
	Current and long-term assets include deferred tax assets. Current and long-term liabilities consist primarily of estimated lease payments, less sublease income, for the Phase I facility.

Business_Acquisitions_Notes

Business Acquisitions (Notes)	9 Months Ended
	Sep. 28, 2013
Business Combinations [Abstract]
Business Combination Disclosure [Text Block]	BUSINESS ACQUISITIONS
	Vital River
	In October 2012, we entered into an agreement to acquire a 75%- ownership interest of Vital River, a commercial provider of research models and related services in China, for $26,890 in cash, subject to certain closing adjustments. The acquisition closed in January 2013. Vital River's financial results are included in our RMS reportable business segment.
	The purchase price allocation, net of $2,671 of cash acquired, is as follows:
	Current assets (excluding cash)	$	3,092
	Property, plant and equipment	10,468
	Other long-term assets	2,242
	Definite-lived intangible assets	16,281
	Goodwill	19,096
	Current liabilities	(11,790		)
	Long term liabilities	(6,207		)
	Redeemable noncontrolling interest	(8,963		)
	Total purchase price allocation	$	24,219
	The breakout of definite-lived intangible assets acquired is as follows:
					Weighted average amortization life (in years)
	Client relationships	$	14,292		11.7 years
	Reacquired rights	1,829			1.3 years
	Other intangible assets	160			2.8 years
	Total definite-lived intangible assets	$	16,281
	The definite-lived intangibles are largely attributed to the expected cash flows related to customer relationships existing at the acquisition closing date. In addition, the Company reacquired a right previously granted to the entity related to a royalty agreement for the distribution of products in China. The value assigned to the reacquired right is being amortized over the remaining life of the existing royalty agreement. The goodwill resulting from the transaction is primarily attributed to the potential growth of the business in China. The goodwill is not deductible for tax purposes.
	Concurrent with the acquisition, the Company entered into a joint venture agreement with the noncontrolling interest holders that provide the Company with the right to purchase the remaining 25% of the entity for cash at its then appraised value beginning in January 2016. Additionally, the noncontrolling interest holders were granted the right to require the Company to purchase the remaining 25% of the entity at its then appraised value beginning in January 2016 for cash. These rights are accelerated in certain events. As the noncontrolling interest holders can require the Company to purchase for cash the remaining 25% interest, we classify the carrying amount of the noncontrolling interest above the equity section and below liabilities on the consolidated balance sheet and we adjust the carrying amount to fair value each quarter end. Adjustments to fair value are recorded through additional paid-in capital.
	EMD Singapore
	On October 4, 2013, we acquired an EMD products and service provider located in Singapore for approximately $5,000 in cash, subject to certain closing adjustments. The financial results of the acquired entity will be included in our RMS reportable business segment.

Fair_Value_Policies

Fair Value (Policies)	9 Months Ended
	Sep. 28, 2013
Fair Value Disclosures [Abstract]
Derivative Instruments	We enter into derivative instruments to hedge foreign currency exchange risk to reduce the impact of changes to foreign currency rates on our financial statements.

Restructuring_Costs_Tables

Restructuring Costs (Tables)	9 Months Ended
	Sep. 28, 2013
Restructuring and Related Activities [Abstract]
Schedule of Severance and Retention Costs	The following table rolls forward our severance and retention cost liability:
		Nine Months Ended
		September 28, 2013			September 29, 2012
	Balance, beginning of period	$	3,636		$	3,374
	Expense	1,058			1,881
	Payments/utilization	(2,084		)	(1,415		)
	Balance, end of period	$	2,610		$	3,840
	The following table presents severance and retention costs by classification on the income statement:
		Nine Months Ended
		September 28, 2013			September 29, 2012
	Severance charges included in cost of sales	$	989		$	936
	Severance charges included in selling, general and administrative expense	69			945
	Total expense	$	1,058		$	1,881
	The following table presents severance and retention cost by segment:
		Nine Months Ended
		September 28, 2013			September 29, 2012
	Research models and services	$	811		$	934
	Preclinical services	247			947
	Total expense	$	1,058		$	1,881

Supplemental_Balance_Sheet_Inf1

Supplemental Balance Sheet Information (Tables)	9 Months Ended
	Sep. 28, 2013
Supplemental Balance Sheet Information [Abstract]
Composition of Net Trade Receivables	The composition of net trade receivables is as follows:
		28-Sep-13			29-Dec-12
	Client receivables	$	191,183		$	174,774
	Unbilled revenue	38,398			32,494
	Total	229,581			207,268
	Less allowance for doubtful accounts	(5,311		)	(4,267		)
	Net trade receivables	$	224,270		$	203,001
Composition of Inventories	The composition of inventories is as follows:
		September 28, 2013			December 29, 2012
	Raw materials and supplies	$	14,662		$	14,525
	Work in process	10,894			11,082
	Finished products	61,590			62,863
	Inventories	$	87,146		$	88,470
Composition of Other Current Assets	The composition of other current assets is as follows:
		September 28, 2013			December 29, 2012
	Prepaid assets	$	28,860		$	20,404
	Deferred tax asset	29,832			30,018
	Marketable securities	11,084			6,781
	Prepaid income tax	35,148			26,169
	Restricted cash	229			229
	Other current assets	$	105,153		$	83,601
Composition of Net Property, Plant and Equipment	The composition of net property, plant and equipment is as follows:
		September 28, 2013			December 29, 2012
	Land	$	40,638		$	40,812
	Buildings	704,262			697,547
	Machinery and equipment	373,431			356,960
	Leasehold improvements	36,907			34,916
	Furniture and fixtures	24,867			25,681
	Vehicles	4,028			3,736
	Computer hardware and software	111,025			107,171
	Construction in progress	33,396			46,186
	Total	1,328,554			1,313,009
	Less accumulated depreciation	(637,829		)	(595,989		)
	Net property, plant and equipment	$	690,725		$	717,020
Composition of Other Assets	The composition of other assets is as follows:
		September 28, 2013			December 29, 2012
	Deferred financing costs	$	7,563		$	6,424
	Cash surrender value of life insurance policies	25,625			26,071
	Equity-method affiliates	15,999			8,492
	Other assets	7,983			7,672
	Other assets	$	57,170		$	48,659
Composition of Current Liabilities	The composition of other current liabilities is as follows:
		September 28, 2013			December 29, 2012
	Accrued income taxes	$	18,260		$	18,216
	Current deferred tax liability	469			410
	Accrued interest and other	1,884			2,636
	Other current liabilities	$	20,613		$	21,262
Composition of Other Long-Term Liabilities	The composition of other long-term liabilities is as follows:
		September 28, 2013			December 29, 2012
	Deferred tax liability	$	16,530		$	13,147
	Long-term pension liability	35,333			44,316
	Accrued Executive Supplemental Life Insurance Retirement Plan and Deferred Compensation Plan	28,518			26,663
	Other long-term liabilities	21,343			20,840
	Other long-term liabilities	$	101,724		$	104,966

Marketable_Securities_and_Equi1

Marketable Securities and Equity-Method Affiliates (Tables)	9 Months Ended
	Sep. 28, 2013
Marketable Securities and Equity-Method Affiliates [Abstract]
Schedule of Marketable Securities by Major Security Type	The amortized cost, gross unrealized gains, gross unrealized losses and fair value for marketable securities by major security type were as follows:
		September 28, 2013
		Amortized		Gross		Gross		Fair
		Cost		Unrealized		Unrealized		Value
				Gains		Losses
	Time deposits	$	11,084	$	—	$	—	$	11,084
		$	11,084	$	—	$	—	$	11,084
		December 29, 2012
		Amortized		Gross		Gross		Fair
		Cost		Unrealized		Unrealized		Value
				Gains		Losses
	Time deposits	$	6,781	$	—	$	—	$	6,781
		$	6,781	$	—	$	—	$	6,781
Schedule of Maturities of Debt Securities	Maturities of debt securities were as follows:
		September 28, 2013				December 29, 2012
		Amortized		Fair		Amortized		Fair
		Cost		Value		Cost		Value
	Due less than one year	$	11,084	$	11,084	$	6,781	$	6,781
	Due after one year through five years	—		—		—		—
	Due after ten years	—		—		—		—
		$	11,084	$	11,084	$	6,781	$	6,781

Fair_Value_Tables

Fair Value (Tables)	9 Months Ended
	Sep. 28, 2013
Fair Value Disclosures [Abstract]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]
		Fair Value Measurements
		Using Significant
		Unobservable Inputs
		(Level 3)
		Nine Months Ended
	Redeemable Noncontrolling Interest (Liability)	September 28, 2013		September 29, 2012
	Beginning balance	$	—	$	—
	Transfers in and/or out of Level 3	—		—
	Total gains or losses (realized/unrealized):
	Included in other income (expense)	476		—
	Included in other comprehensive income (CTA)	233		—
	Included in additional paid-in capital	4,905
	Purchases, issuances and settlements	8,963		—
	Ending balance	$	14,577	$	—
Summary of Assets and Liabilities Measured at Fair Value on a Recurring Basis	Assets and liabilities measured at fair value on a recurring basis are summarized below:
		Fair Value Measurements at September 28, 2013
		Quoted Prices in Active Markets for Identical Assets Level 1		Significant Other Observable Inputs Level 2			Significant Unobservable Inputs Level 3		Assets and Liabilities at Fair Value
	Time deposits	$	—	$	11,084		$	—	$	11,084
	Life policies	—		18,893			—		18,893
	Total assets measured at fair value	$	—	$	29,977		$	—	$	29,977
	Redeemable noncontrolling interest	—		—			14,577		14,577
	Total liabilities measured at fair value	$	—	$	—		$	14,577	$	14,577
		Fair Value Measurements at December 29, 2012
		Quoted Prices in Active Markets for Identical Assets Level 1		Significant Other Observable Inputs Level 2			Significant Unobservable Inputs Level 3		Assets and Liabilities at Fair Value
	Time deposits	$	—	$	6,781		$	—	$	6,781
	Life policies	—		19,555			—		19,555
	Hedge contract	—		16			—		16
	Total assets measured at fair value	$	—	$	26,352		$	—	$	26,352
	Redeemable noncontrolling interest	—		—			—		—
	Total liabilities measured at fair value	$	—	$	—		$	—	$	—
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]
		Fair Value Measurements
		Using Significant
		Unobservable Inputs
		(Level 3)
		Nine Months Ended
	Auction rate securities (Asset)	September 28, 2013		September 29, 2012
	Beginning balance	$	—	$	11,051
	Transfers in and/or out of Level 3	—		—
	Total gains or losses (realized/unrealized):
	Included in other income (expense)	—		(712		)
	Included in other comprehensive income	—		921
	Purchases, issuances and settlements	—		(11,260		)
	Ending balance	$	—	$	—

Goodwill_and_Other_Intangible_1

Goodwill and Other Intangible Assets (Tables)	9 Months Ended
	Sep. 28, 2013
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill and Other Intangible Assets not Subject to Amortization and Other Intangible Assets that Continue to be Subject to Amortization	The following table displays the gross carrying amount and accumulated amortization of definite-lived intangible assets by major class:
		September 28, 2013							December 29, 2012
		Gross Carrying Amount				Accumulated Amortization & Impairment Loss			Gross Carrying Amount			Accumulated Amortization & Impairment Loss
	Backlog	$	2,899			$	(2,469	)	$	2,875		$	(2,375	)
	Client relationships	313,595				(238,245		)	305,178			(231,902		)
	Client contracts	15,339				(15,339		)	15,366			(15,366		)
	Trademarks and trade names	5,380				(4,949		)	5,326			(4,821		)
	Standard operating procedures	2,753				(1,339		)	2,751			(863		)
	Other identifiable intangible assets	10,384				(4,202		)	10,033			(4,718		)
	Total other intangible assets	$	350,350			$	(266,543	)	$	341,529		$	(260,045	)
Schedule of Changes in the Gross Carrying Amount and Accumulated Amortization of Goodwill	The changes in the gross carrying amount and accumulated impairment loss of goodwill are as follows:
							Adjustments to Goodwill
			29-Dec-12				Acquisitions			Foreign Exchange			28-Sep-13
	Research Models and Services
	Gross carrying amount		$	63,139			$	19,273		$	361		$	82,773
	Preclinical Services
	Gross carrying amount		1,150,470				—			1,028			1,151,498
	Accumulated impairment loss		(1,005,000		)								(1,005,000		)
	Total
	Gross carrying amount		$	1,213,609			$	19,273		$	1,389		$	1,234,271
	Accumulated impairment loss		(1,005,000		)								(1,005,000		)
	Goodwill, net		$	208,609									$	229,271

LongTerm_Debt_and_Capital_Leas1

Long-Term Debt and Capital Lease Obligations (Tables)	9 Months Ended
	Sep. 28, 2013
Debt Disclosure [Abstract]
Components of Long-Term Debt	Long-term debt consists of the following:
		September 28, 2013			December 29, 2012
	2.25% Senior convertible debentures:
	Principal	$	—		$	349,995
	Unamortized debt discount	—			(6,726		)
	Net carrying amount of senior convertible debentures	—			343,269
	Term loan facilities	414,750			290,947
	Revolving credit facility	224,752			32,000
	Other long-term debt	237			232
	Total debt	639,739			666,448
	Less: current portion of long-term debt	(15,987		)	(139,373		)
	Long-term debt	$	623,752		$	527,075
Schedule of Principal Maturities of Existing Debt Excluding Unamortized Debt Discount	Principal maturities of existing debt for the periods set forth in the table below, are as follows:
	Twelve Months Ending
	Sep-14	$	15,987
	Sep-15	42,000
	Sep-16	42,000
	Sep-17	63,000
	Sep-18	476,752
	Total	$	639,739

Equity_Tables

Equity (Tables)	9 Months Ended
	Sep. 28, 2013
Stockholders' Equity Note [Abstract]
Reconciliation of the Numerator and Denominator in the Computations of the Basic and Diluted Earnings Per Share	The following table illustrates the reconciliation of the numerator and denominator in the computations of the basic and diluted earnings per share:
		Three Months Ended						Nine Months Ended
		September 28, 2013			September 29, 2012			September 28, 2013			September 29, 2012
	Numerator:
	Income from continuing operations for purposes of calculating earnings per share	$	30,980		$	22,154		$	84,912		$	78,942
	Income (loss) from discontinued businesses	(113		)	$	(182	)	$	(1,183	)	$	(63	)
	Denominator:
	Weighted-average shares outstanding—Basic	47,910,649			47,625,806			47,950,018			48,028,602
	Effect of dilutive securities:
	2.25% senior convertible debentures	—			—			—			—
	Stock options and contingently issued restricted stock	530,516			482,808			704,118			447,544
	Weighted-average shares outstanding—Diluted	48,441,165			48,108,614			48,654,136			48,476,146
	Basic earnings per share from continuing operations attributable to common shareholders	$	0.65		$	0.47		$	1.77		$	1.64
	Basic earnings (loss) per share from discontinued operations attributable to common shareholders	$	—		$	—		$	(0.02	)	$	—
	Diluted earnings per share from continuing operations attributable to common shareholders	$	0.64		$	0.46		$	1.75		$	1.63
	Diluted earnings (loss) per share from discontinued operations attributable to common shareholders	$	—		$	—		$	(0.02	)	$	—
Schedule of Number of Shares Repurchased and the Total Cost of Repurchase	Share repurchases for the nine months ended September 28, 2013 and September 29, 2012 were as follows:
		Nine Months Ended
		September 28, 2013			September 29, 2012
	Number of shares of common stock repurchased	2,057,769			1,306,518
	Total cost of repurchase	$	93,072		$	45,842
	On July 30, 2013, our Board of Directors increased the stock repurchase authorization to $850,000 from $750,000.

Income_Taxes_Tables

Income Taxes (Tables)	9 Months Ended
	Sep. 28, 2013
Income Tax Disclosure [Abstract]
Reconciliation of Provision for Income Taxes on Condensed Consolidated Statements of Operations	The following table provides a reconciliation of the provision for income taxes on the condensed consolidated statements of income:
		Three Months Ended						Nine Months Ended
		September 28, 2013			September 29, 2012			September 28, 2013			September 29, 2012
	Income from continuing operations before income taxes	$	42,726		$	28,395		$	115,221		$	103,541
	Effective tax rate	26.7		%	21.2		%	25.5		%	23.3		%
	Provision for income taxes	$	11,390		$	6,011		$	29,331		$	24,140

Employee_Benefits_Tables

Employee Benefits (Tables)	3 Months Ended
	Sep. 28, 2013
Compensation and Retirement Disclosure [Abstract]
Components of Net Periodic Benefit Cost for Defined Benefit Plans	The following table provides the components of net periodic benefit cost for our defined benefit plans for the three month period ended:
		Pension Benefits						Supplemental
								Retirement Benefits
		September 28, 2013			September 29, 2012			September 28, 2013		September 29, 2012
	Service cost	$	822		$	922		$	160	$	160
	Interest cost	2,762			2,824			177		223
	Expected return on plan assets	(3,593		)	(3,459		)	—		—
	Amortization of prior service cost (credit)	(147		)	(256		)	165		165
	Amortization of net loss (gain)	671			586			63		65
	Net periodic benefit cost	$	515		$	617		$	565	$	613

Stock_Plans_and_StockBased_Com1

Stock Plans and Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 28, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Stock-Based Compensation Expense	The following table presents stock-based compensation included in our consolidated statement of income:
		Three Months Ended								Nine Months Ended
		September 28, 2013				September 29, 2012				September 28, 2013			September 29, 2012
	Stock-based compensation expense included in:
	Cost of sales	$	1,332			$	1,271			$	4,051		$	3,995
	Selling, general and administration	4,715				3,970				14,181			11,833
	Stock-based compensation, before income taxes	6,047				5,241				18,232			15,828
	Provision for income taxes	(2,103		)		(1,847		)		(6,422		)	(5,615		)
	Stock-based compensation, net of tax	$	3,944			$	3,394			$	11,810		$	10,213
Schedule of Weighted-Average Assumptions	The fair value of stock-based awards granted during the first nine months of 2013 and 2012 was estimated on the grant date using the Black-Scholes option-pricing model with the following weighted-average assumptions:
		September 28, 2013				September 29, 2012
	Expected life (in years)	4.2 years				4.5 years
	Expected volatility	32.7		%		34.9		%
	Risk-free interest rate	0.8		%		0.84		%
	Expected dividend yield	0		%		0		%
	Weighted-average grant date fair value	$	11.17			$	10.94
Summary of Stock Option Activity in Equity Incentive Plans	The following table summarizes stock option activities under our plans:
		Shares			Weighted Average				Weighted Average		Aggregate
					Exercise Price				Remaining		Intrinsic
									Contractual Life		Value
									(in years)
	Options outstanding as of December 29, 2012	5,860,403			$	39.11
	Options granted	593,499			$	40.54
	Options exercised	(1,729,768	)		$	34.06
	Options canceled	(105,040	)		$	45.68
	Options outstanding as of September 28, 2013	4,619,094			$	41.04			3.25 years		$	30,997
	Options exercisable as of September 28, 2013	3,022,605			$	42.52			2.00 years		$	18,186
Summary of Restricted Stock Activity	The following table summarizes the restricted stock activity for the nine months ended September 28, 2013:
		Restricted Stock			Weighted
					Average
					Grant Date
					Fair Value
	Outstanding as of December 29, 2012	934,505			$	35.83
	Granted	565,699			40.52
	Vested	(371,458	)		40.37
	Canceled	(21,433	)		43.75
	Outstanding as of September 28, 2013	1,107,313			$	36.55

Business_Segment_Information_T

Business Segment Information (Tables)	3 Months Ended
	Sep. 28, 2013
Segment Reporting [Abstract]
Schedule of Sales and Other Financial Information by Business Segment	The following table presents sales and other financial information by business segment.
		Three Months Ended						Nine Months Ended
		September 28, 2013			September 29, 2012			September 28, 2013			September 29, 2012
	Research Models and Services
	Net sales	$	173,405		$	166,484		$	534,867		$	523,247
	Gross margin	65,710			65,902			221,916			224,364
	Operating income	40,260			43,389			145,193			158,398
	Depreciation and amortization	16,876			9,670			37,378			27,697
	Capital expenditures	6,110			7,423			16,464			27,892
	Preclinical Services
	Net sales	$	118,724		$	112,202		$	341,433		$	326,143
	Gross margin	34,216			27,358			84,791			76,693
	Operating income	18,636			10,975			37,631			25,958
	Depreciation and amortization	10,039			10,880			29,957			32,920
	Capital expenditures	2,986			2,819			8,855			5,903
Reconciliation of Segment Operating Income to Consolidated Operating Income	A reconciliation of segment operating income to consolidated operating income is as follows:
		Three Months Ended						Nine Months Ended
		September 28, 2013			September 29, 2012			September 28, 2013			September 29, 2012
	Total segment operating income	$	58,896		$	54,364		$	182,824		$	184,356
	Unallocated corporate overhead	(18,053		)	(16,682		)	(56,030		)	(53,660		)
	Consolidated operating income	$	40,843		$	37,682		$	126,794		$	130,696
Schedule of Net Sales for Each Significant Service Area	Net sales for each significant service area are as follows:
		Three Months Ended						Nine Months Ended
		September 28, 2013			September 29, 2012			September 28, 2013			September 29, 2012
	Research models	$	92,969		$	90,877		$	294,993		$	293,575
	Research model services	52,105			53,400			156,661			163,247
	EMD	28,331			22,207			83,213			66,425
	Total research models and services	173,405			166,484			534,867			523,247
	Total preclinical services	118,724			112,202			341,433			326,143
	Total sales	$	292,129		$	278,686		$	876,300		$	849,390
Summary of Unallocated Corporate Overhead	A summary of unallocated corporate overhead consists of the following:
		Three Months Ended						Nine Months Ended
		September 28, 2013			September 29, 2012			September 28, 2013			September 29, 2012
	Stock-based compensation expense	$	3,260		$	2,827		$	9,927		$	8,512
	U.S. retirement plans	1,275			1,276			3,617			3,662
	Audit, tax and related expense	811			842			3,135			2,133
	Salary and bonus	5,831			4,813			16,057			14,602
	Global IT	3,002			3,285			8,448			9,501
	Employee health, long-term disability and fringe benefit expense	(1,470		)	(2,248		)	(898		)	(1,395		)
	Consulting and professional services	1,439			1,061			3,443			3,581
	Depreciation expense	1,570			1,554			4,712			4,693
	Other general unallocated corporate expenses	2,335			3,272			7,589			8,371
	Total unallocated corporate overhead costs	$	18,053		$	16,682		$	56,030		$	53,660

Discontinued_Operations_Tables

Discontinued Operations (Tables)	9 Months Ended
	Sep. 28, 2013
Discontinued Operations and Disposal Groups [Abstract]
Schedule of Operating Results from Discontinued Operations	Operating results from discontinued operations are as follows:
		Three Months Ended						Nine Months Ended
		September 28, 2013			September 29, 2012			September 28, 2013			September 29, 2012
	Net sales	$	—		$	—		$	—		$	—
	Income (loss) from operations of discontinued businesses, before income taxes	(172		)	49			(1,894		)	221
	Provision (benefit) for income taxes	(59		)	231			(711		)	284
	Income (loss) from operations of discontinued businesses, net of taxes	$	(113	)	$	(182	)	$	(1,183	)	$	(63	)
Schedule of Assets and Liabilities of Discontinued Operations	Assets and liabilities of discontinued operations at September 28, 2013 and December 29, 2012 consisted of the following:
		September 28,			December 29,
		2013			2012
	Current assets	$	758		$	495
	Long-term assets	3,326			3,328
	Total assets	$	4,084		$	3,823
	Current liabilities	$	1,944		$	1,802
	Long-term liabilities	8,531			8,795
	Total liabilities	$	10,475		$	10,597

Business_Acquisitions_Tables

Business Acquisitions (Tables)	9 Months Ended
	Sep. 28, 2013
Business Combinations [Abstract]
Schedule of Purchase Price Allocation [Table Text Block]	The purchase price allocation, net of $2,671 of cash acquired, is as follows:
	Current assets (excluding cash)	$	3,092
	Property, plant and equipment	10,468
	Other long-term assets	2,242
	Definite-lived intangible assets	16,281
	Goodwill	19,096
	Current liabilities	(11,790		)
	Long term liabilities	(6,207		)
	Redeemable noncontrolling interest	(8,963		)
	Total purchase price allocation	$	24,219
Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table Text Block]	The breakout of definite-lived intangible assets acquired is as follows:
					Weighted average amortization life (in years)
	Client relationships	$	14,292		11.7 years
	Reacquired rights	1,829			1.3 years
	Other intangible assets	160			2.8 years
	Total definite-lived intangible assets	$	16,281
Redeemable Noncontrolling Interest [Table Text Block]	Concurrent with the acquisition, the Company entered into a joint venture agreement with the noncontrolling interest holders that provide the Company with the right to purchase the remaining 25% of the entity for cash at its then appraised value beginning in January 2016. Additionally, the noncontrolling interest holders were granted the right to require the Company to purchase the remaining 25% of the entity at its then appraised value beginning in January 2016 for cash. These rights are accelerated in certain events. As the noncontrolling interest holders can require the Company to purchase for cash the remaining 25% interest, we classify the carrying amount of the noncontrolling interest above the equity section and below liabilities on the consolidated balance sheet and we adjust the carrying amount to fair value each quarter end. Adjustments to fair value are recorded through additional paid-in capital.
	EMD Singapore
	On October 4, 2013, we acquired an EMD products and service provider located in Singapore for approximately $5,000 in cash, subject to certain closing adjustments. The financial results of the acquired entity will be included in our RMS reportable business segment.

Restructuring_Costs_Details

Restructuring Costs (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Dec. 28, 2013	Sep. 28, 2013	Sep. 28, 2013	Sep. 29, 2012
Restructuring Cost and Reserve [Line Items]
Accelerated depreciation estimate	$7,000	$6,766
Severance and Retention Costs
Balance, beginning of period	2,610		3,636	3,374
Expense			1,058	1,881
Payments for Restructuring			-2,084	-1,415
Balance, end of period		2,610	2,610	3,840
Severance and retention costs, current		1,197	1,197
Severance and retention costs, noncurrent		1,413	1,413
Severance and retention costs			1,058	1,881
Research Models and Services [Member]
Severance and Retention Costs
Severance and retention costs			811	934
Preclinical Services [Member]
Severance and Retention Costs
Severance and retention costs			247	947
Cost of Sales [Member]
Severance and Retention Costs
Severance and retention costs			989	936
General and Administrative Expense [Member]
Severance and Retention Costs
Severance and retention costs			$69	$945

Supplemental_Balance_Sheet_Inf2

Supplemental Balance Sheet Information (Details) (USD $)	Sep. 28, 2013	Dec. 29, 2012
In Thousands, unless otherwise specified
Composition of trade receivables
Client receivables	$191,183	$174,774
Unbilled revenue	38,398	32,494
Total	229,581	207,268
Less allowance for doubtful accounts	-5,311	-4,267
Net trade receivables	224,270	203,001
Composition of inventories
Raw materials and supplies	14,662	14,525
Work in process	10,894	11,082
Finished products	61,590	62,863
Inventories	87,146	88,470
Composition of other current assets
Prepaid assets	28,860	20,404
Deferred tax asset	29,832	30,018
Marketable securities	11,084	6,781
Prepaid income tax	35,148	26,169
Restricted cash	229	229
Other current assets	105,153	83,601
Composition of other assets
Deferred financing costs	7,563	6,424
Cash surrender value of life insurance policies	25,625	26,071
Long-term marketable securities	15,999	8,492
Other assets	7,983	7,672
Other assets	57,170	48,659
Composition of other current liabilities
Accrued income taxes	18,260	18,216
Current deferred tax liability	469	410
Accrued intereset and other	1,884	2,636
Other current liabilities	20,613	21,262
Composition of other long-term liabilities
Deferred tax liability	16,530	13,147
Long-term pension liability	35,333	44,316
Accrued Executive Supplemental Life Insurance Retirement Plan and Deferred Compensation Plan	28,518	26,663
Other long-term liabilities	21,343	20,840
Other long-term liabilities	$101,724	$104,966

Supplemental_Balance_Sheet_Inf3

Supplemental Balance Sheet Information (Long-lived Assets) (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Dec. 29, 2012
Net property, plant and equipment
Gross property, plant and equipment	$1,328,554		$1,313,009
Less accumulated depreciation	-637,829		-595,989
Net property, plant and equipment	690,725		717,020
Depreciation expense	54,444	47,181
Land [Member]
Net property, plant and equipment
Gross property, plant and equipment	40,638		40,812
Buildings [Member]
Net property, plant and equipment
Gross property, plant and equipment	704,262		697,547
Machinery and Equipment [Member]
Net property, plant and equipment
Gross property, plant and equipment	373,431		356,960
Leashold Improvements [Member]
Net property, plant and equipment
Gross property, plant and equipment	36,907		34,916
Furniture and Fixtures [Member]
Net property, plant and equipment
Gross property, plant and equipment	24,867		25,681
Vehicles [Member]
Net property, plant and equipment
Gross property, plant and equipment	4,028		3,736
Computer Hardware and Software [Member]
Net property, plant and equipment
Gross property, plant and equipment	111,025		107,171
Construction in Progress [Member]
Net property, plant and equipment
Gross property, plant and equipment	$33,396		$46,186

Marketable_Securities_and_Equi2

Marketable Securities and Equity-Method Affiliates (Marketable Securities) (Details) (USD $)	9 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Dec. 28, 2013	Dec. 29, 2012
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$11,084		$6,781
Gross Unrealized Gains	0		0
Gross Unrealized Losses	0	0
Fair Value	11,084		6,781
Maturities of debt securities, Amortized Cost
Due less than one year, Amortized Cost	11,084		6,781
Due after one year through five years, Amortized Cost	0		0
Due after ten years, Amortized Cost	0		0
Amortized Cost	11,084		6,781
Maturities of debt securities, Fair Value
Dus less than one year, Fair Value	11,084		6,781
Due after one year through five years, Fair Value	0		0
Due after ten years, Fair Value	0		0
Time Deposits [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	11,084		6,781
Gross Unrealized Gains	0		0
Gross Unrealized Losses	0		0
Fair Value	$11,084		$6,781

Marketable_Securities_and_Equi3

Marketable Securities and Equity-Method Affiliates (Equity-Method Affiliates) (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013
Schedule of Equity Method Investments [Line Items]
Number of Equity-Method Investees	2
Income (loss) from limited partnership	$4,832
Equity method affiliates, carrying value	15,999
Biotechnology and Medical Device Companies [Member]
Schedule of Equity Method Investments [Line Items]
Limited partnership, committed contribution	20,000
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	9,420
Limited partnership, ownership (as a percentage)	12.00%
technology and life sciences [Member] [Member]
Schedule of Equity Method Investments [Line Items]
Limited partnership, committed contribution	10,000
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	$2,075
Limited partnership, ownership (as a percentage)	4.00%

Fair_Value_Summary_of_Assets_a

Fair Value (Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Dec. 29, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	18.00%
Available-for-sale Securities, Fair Value Disclosure	$11,084	$6,781
Fair value of life policies	18,893	19,555
Hedge contract		16
Total assets measured at fair value	29,977	26,352
Redeemable Noncontrolling Interest, Equity, Fair Value	14,577	0
Total liabilities measured at fair value	14,577	0
Fair Value Inputs, Long-term Pre-tax Operating Margin, Percent	28.00%
Forward Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Hedge gains recorded	289
Outstanding forward contract, fair value	0
Quoted Prices in Active Markets for Identical Assets Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	0
Fair value of life policies	0	0
Hedge contract		0
Total assets measured at fair value	0	0
Redeemable Noncontrolling Interest, Equity, Fair Value	0	0
Total liabilities measured at fair value	0	0
Significant Other Observable Inputs Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	11,084	6,781
Fair value of life policies	18,893	19,555
Hedge contract		16
Total assets measured at fair value	29,977	26,352
Redeemable Noncontrolling Interest, Equity, Fair Value	0	0
Total liabilities measured at fair value	0	0
Significant Unobservable Inputs Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	0	0
Fair value of life policies	0	0
Hedge contract		0
Total assets measured at fair value	0	0
Redeemable Noncontrolling Interest, Equity, Fair Value	14,577	0
Total liabilities measured at fair value	$14,577	$0

Fair_Value_Level_3_Reconciliat

Fair Value Level 3 Reconciliation Liabilities (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Dec. 29, 2012	Dec. 31, 2011
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	$14,577		$0	$0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Transfers, Net	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	476	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Other Comprehensive Income (Loss)	233	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers out of Level 3	4,905
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases	$8,963	$0

Fair_Value_Level_3_Fair_Value_

Fair Value Level 3 Fair Value Reconciliation Assets (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Dec. 29, 2012	Dec. 31, 2011
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$0	$0	$0	$11,051
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0	-712
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	0	921
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	$0	($11,260)

Goodwill_and_Other_Intangible_2

Goodwill and Other Intangible Assets (Schedule of Goodwill and Other Intangible Assets) (Details) (USD $)	Sep. 28, 2013	Dec. 29, 2012
In Thousands, unless otherwise specified
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill, Gross Carrying Amount	$1,234,271	$1,213,609
Other intangible assets
Other intangible assets subject to amortization, Gross Carrying Amount	350,350	341,529
Other intangible assets subject to amortization, Accumulated Amortization & Impairment Loss	-266,543	-260,045
Backlog [Member]
Other intangible assets
Other intangible assets subject to amortization, Gross Carrying Amount	2,899	2,875
Other intangible assets subject to amortization, Accumulated Amortization & Impairment Loss	-2,469	-2,375
Client Relationships [Member]
Other intangible assets
Other intangible assets subject to amortization, Gross Carrying Amount	313,595	305,178
Other intangible assets subject to amortization, Accumulated Amortization & Impairment Loss	-238,245	-231,902
Client Contracts [Member]
Other intangible assets
Other intangible assets subject to amortization, Gross Carrying Amount	15,339	15,366
Other intangible assets subject to amortization, Accumulated Amortization & Impairment Loss	-15,339	-15,366
Trademarks and Trade Names [Member]
Other intangible assets
Other intangible assets subject to amortization, Gross Carrying Amount	5,380	5,326
Other intangible assets subject to amortization, Accumulated Amortization & Impairment Loss	-4,949	-4,821
Standard Operating Procedures [Member]
Other intangible assets
Other intangible assets subject to amortization, Gross Carrying Amount	2,753	2,751
Other intangible assets subject to amortization, Accumulated Amortization & Impairment Loss	-1,339	-863
Other Identifiable Intangible Assets [Member]
Other intangible assets
Other intangible assets subject to amortization, Gross Carrying Amount	10,384	10,033
Other intangible assets subject to amortization, Accumulated Amortization & Impairment Loss	-4,202	-4,718
Research Models [Member]
Other intangible assets
Other intangible assets not subject to amortization, Gross Carrying Amount	$3,438	$3,438

Goodwill_and_Other_Intangible_3

Goodwill and Other Intangible Assets (Gross Carrying Amount and Accumulated Amortization of Goodwill) (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Sep. 28, 2013	Jan. 04, 2013	Dec. 29, 2012
Changes in gross carrying amount and accumulated amortization of goodwill
Gross carrying amount, balance at the beginning of the period	$1,213,609	$1,234,271
Gross carrying amount, acquired during the period	19,273
Gross carrying amount, foreign exchange/impairment	1,389
Accumulated impairment loss, balance at the beginning of the period	-1,005,000	-1,005,000
Goodwill	229,271		19,096	208,609
Research Models and Services [Member]
Changes in gross carrying amount and accumulated amortization of goodwill
Gross carrying amount, balance at the beginning of the period	63,139	82,773
Gross carrying amount, acquired during the period	19,273
Gross carrying amount, foreign exchange/impairment	361
Preclinical Services [Member]
Changes in gross carrying amount and accumulated amortization of goodwill
Gross carrying amount, balance at the beginning of the period	1,150,470	1,151,498
Gross carrying amount, acquired during the period	0
Gross carrying amount, foreign exchange/impairment	1,028
Accumulated impairment loss, balance at the beginning of the period	($1,005,000)	($1,005,000)

LongTerm_Debt_and_Capital_Leas2

Long-Term Debt and Capital Lease Obligations (Long-Term Debt) (Details) (USD $)	Sep. 28, 2013	Dec. 29, 2012
In Thousands, unless otherwise specified
Debt Instrument
Principal	$639,739
Total debt	639,739	666,448
Less: current portion of long-term debt	-15,987	-139,373
Long-term debt	623,752	527,075
Interest rate on debt (as a percent)	2.25%
2.25% Senior convertible debentures
Debt Instrument
Principal	0	349,995
Unamortized debt discount	0	-6,726
Total debt	0	343,269
Interest rate on debt (as a percent)	2.25%
Term loan facilities
Debt Instrument
Total debt	414,750	290,947
Revolving credit facility
Debt Instrument
Total debt	224,752	32,000
Other long-term debt represents secured and unsecured promissory notes, interest rates ranging from 0% to 0.5%, 0% to 0.5% at both March 31, 2012 and December 31, 2011, respectively, maturing between 2012 and 2013
Debt Instrument
Total debt	$237	$232

LongTerm_Debt_and_Capital_Leas3

Long-Term Debt and Capital Lease Obligations (Additional Disclosures) (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Dec. 29, 2012
Debt Instrument [Line Items]
Maximum borrowing capacity, Term Loan and Line of Credit	$970,000
US Term Loan	420,000
Maximum borrowing capacity, Line of Credit	550,000
Credit Facility Borrowing Capacity Available Increase	350,000
Gains (Losses) on Extinguishment of Debt	389
Debt Instrument, Basis Spread on Variable Rate	1.25%
Outstanding under letters of credit	4,855
Debt Instrument, Face Amount	350,000
Interest rate on debt (as a percent)	2.25%
Long-term Debt, Excluding Current Maturities	623,752	527,075
Capital lease obligations	741	72
Principal maturities of existing debt excluding unamortized debt discount
Jun-14	15,987
Jun-15	42,000
Jun-16	42,000
Jun-17	63,000
Jun-18	476,752
Total	639,739
2.25% Senior convertible debentures
Debt Instrument [Line Items]
Interest rate on debt (as a percent)	2.25%
Unamortized debt discount	0	6,726
Principal maturities of existing debt excluding unamortized debt discount
Total	$0	$349,995

Equity_Earnings_Per_Share_Deta

Equity (Earnings Per Share) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
Numerator:
Income from continuing operations for purposes of calculating earnings per share	$30,980	$22,154	$84,912	$78,942
Income (loss) from discontinued operations	($113)	($182)	($1,183)	($63)
Denominator:
Weighted average shares outstanding-Basic (in shares)	47,910,649	47,625,806	47,950,018	48,028,602
Effect of dilutive securities:
2.25% senior convertible debentures (in shares)	0	0	0	0
Stock options and contingently issued restricted stock (in shares)	530,516	482,808	704,118	447,544
Weighted Average Number of Shares Outstanding, Diluted	48,441,165	48,108,614	48,654,136	48,476,146
Basic earnings per share from continuing operations attributable to common shareowners (in dollars per share)	$0.65	$0.47	$1.77	$1.64
Basic earnings (loss) per share from discontinued operations attributable to common shareowners (in dollars per share)	$0	$0	($0.02)	$0
Diluted earnings per share from continuing operations attributable to common shareowners (in dollars per share)	$0.64	$0.46	$1.75	$1.63
Diluted earnings (loss) per share from discontinued operations attributable to common shareowners (in dollars per share)	$0	$0	($0.02)	$0
Interest rate on debt (as a percent)	2.25%		2.25%
2.25% Senior convertible debentures
Effect of dilutive securities:
Interest rate on debt (as a percent)	2.25%		2.25%
Stock options [Member]
Antidilutive securities excluded from computation of earnings per share amount
Antidilutive securities excluded from computation of earnings per share amount (in shares)	2,652,660	4,667,739	2,363,878	4,590,418
Restricted Stock [Member]
Antidilutive securities excluded from computation of earnings per share amount
Antidilutive securities excluded from computation of earnings per share amount (in shares)	1,107,313	941,873

Equity_Treasury_Stock_Details

Equity (Treasury Stock) (Details) (USD $)	6 Months Ended	9 Months Ended				3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Jun. 29, 2013	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013
				Open market repurchases	Open market repurchases	2007 Incentive Plan	2007 Incentive Plan	2007 Incentive Plan
Treasury Shares and Accelerated Stock Repurchase Program (ASR)
Stock Repurchase Program, Authorized Amount	$750,000	$850,000
Number of shares of common stock repurchased (in shares)		2,057,769	1,306,518	1,945,021	1,222,432	84,086		112,748
Total cost of repurchase of treasury shares		$93,072	$45,842	$88,553	$42,800		$3,042	$4,519

Equity_Warrants_Details

Equity Warrants (Details)	12 Months Ended
In Millions, unless otherwise specified	Dec. 28, 2013	Sep. 28, 2013	Jun. 29, 2013	Jun. 12, 2006
	increments
Class of Warrant or Right [Line Items]
Class of Warrant or Right, Outstanding		6.3	7.2
Class of Warrant or Right, Exercise Price of Warrants or Rights				59.93
Class of Warrant or Right Expiration Period, Number of Equal Increments	90

Income_Taxes_Details

Income Taxes (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012	Dec. 29, 2012
Income Tax Disclosures [Line Items]
Liability for Uncertain Tax Positions, Current	$2,408		$2,408
Transaction Costs Not Deductible			525
Increase (decrease) in unrecognized tax benefits	13,325
Unrecognized tax benefits	18,782		18,782
Increase in unrecognized tax benefits, that if recognized would impact the effective tax rate	-8,628
Unrecognized tax benefits that would impact effective tax rate favorably, if recognized	17,268		17,268
Interest related to unrecognized income tax benefits	637		637
Change in accrued interest related to unrecognized income tax benefits	-1,788
US Tax Asset Correlative Relief	975		975		2,981
Change in US Tax Asset Correlative Relief	2,006
Income tax expense related to items of other comprehensive income	-326	156	874	701
Income tax expense (beneffit) related to foreign currency translation adjustments	-615	-60	42	-98
Income tax expense related to the change in unrecognized pension gains, losses and prior service costs	289	216	832	799
Income (loss) from continuing operations before income taxes
Income from continuing operations, before income taxes	42,726	28,395	115,221	103,541
Effective tax rate (as a percentage)	26.70%	21.20%	25.50%	23.30%
Provision (benefit) for income taxes	11,390	6,011	29,331	24,140
UNITED STATES
Income Tax Disclosures [Line Items]
Discrete Tax Cost or Benefit Due to Change in Tax Law			-330
UNITED KINGDOM
Income Tax Disclosures [Line Items]
Discrete Tax Cost or Benefit Due to Change in Tax Law			1,714
FRANCE
Income Tax Disclosures [Line Items]
Discrete Tax Cost or Benefit Due to Change in Tax Law			703
CANADA
Income Tax Disclosures [Line Items]
Increase (decrease) in unrecognized tax benefits	($1,000)

Employee_Benefits_Details

Employee Benefits (Details) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012	Dec. 28, 2013
Pension Benefits [Member]
Employee benefits
Service cost	$822	$922	$2,492	$2,880
Interest cost	2,762	2,824	8,334	8,445
Expected return on plan assets	-3,593	-3,459	-10,842	-10,319
Amortization of prior service cost (credit)	-147	-256	-444	-566
Amortization of net loss (gain)	671	586	2,043	1,756
Net periodic benefit cost	515	617	1,583	2,196
Expected contributions during the current fiscal year					9,686
Supplemental Retirement Benefits [Member]
Employee benefits
Service cost	160	160	482	480
Interest cost	177	223	531	669
Expected return on plan assets	0	0	0	0
Amortization of prior service cost (credit)	165	165	495	495
Amortization of net loss (gain)	63	65	189	195
Net periodic benefit cost	$565	$613	$1,697	$1,839

Stock_Plans_and_StockBased_Com2

Stock Plans and Stock-Based Compensation (Stock Based Compensation Expense) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
Stock-based compensation expense
Stock-based compensation expense	$6,047	$5,241	$18,232	$15,828
Provision for income taxes	-2,103	-1,847	-6,422	-5,615
Net income attributable to common shareowners	3,944	3,394	11,810	10,213
Cost of Sales [Member]
Stock-based compensation expense
Stock-based compensation expense	1,332	1,271	4,051	3,995
General and Administrative Expense [Member]
Stock-based compensation expense
Stock-based compensation expense	4,715	3,970	14,181	11,833
Performance Based Stock Award Program [Member]
Stock-based compensation expense
Stock-based compensation expense			$1,455

Stock_Plans_and_StockBased_Com3

Stock Plans and Stock-Based Compensation (Stock Options and Restricted Stock Grants) (Details) (USD $)	9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012
Stock-based compensation weighted-average assumptions
Expected life (in years)	4 years 2 months 22 days	4 years 6 months
Expected volatility (as a percent)	32.70%	34.90%
Risk-free interest rate (as a percent)	0.80%	0.84%
Expected dividend yield (as a percent)	0.00%	0.00%
Weighted-average grant date fair value (in dollars per share)	$11.17	$10.94
Stock option activity, additional disclosures
Charge recorded in capital in excess of par value for excess of deferred tax assets over actual tax benefits	($1,362)
Restricted Stock and Performance Units, Additional Disclosure
Min PSU Shares	0
Performance Shares [Member]
Restricted stock activity, restricted stock
Granted (in shares)	163,847
Restricted Stock and Performance Units, Additional Disclosure
Max PSU Shares	327,694
Stock options [Member]
Stock option activity, shares
Options outstanding, balance at the beginning of the period (in shares)	5,860,403
Options granted (in shares)	593,499
Options exercised (in shares)	-1,729,768
Options canceled (in shares)	-105,040
Options outstanding, balance at the end of the period (in shares)	4,619,094
Options exercisable, balance at the end of the period (in shares)	3,022,605
Stock option activity, weighted-average exercise price
Options outstanding, balance at the beginning of the period (in dollars per share)	$39.11
Options granted (in dollars per share)	$40.54
Options exercised (in dollars per share)	$34.06
Options canceled (in dollars per share)	$45.68
Options outstanding, balance at the end of the period (in dollars per share)	$41.04
Options exercisable, balance at the end of the period (in dollars per share)	$42.52
Stock option activity, weighted-average remaining contractual life
Options outstanding, balance at the end of the period (in years)	3 years 3 months 0 days
Options exercisable, balance at the end of the period (in years)	2 years 0 months 1 day
Stock option activity, Aggregate Intrinsic Value
Options outstanding, balance at the end of the period	30,997
Options exercisable, balance at the end of the period	18,186
Unrecognized compensation expense
Number of unvested awards related to unrecognized compensation cost (in shares)	1,596,489
Unrecognized compensation cost	12,634
Estimated weighted-average amortization period for unrecognized compensation cost (in months)	3
Stock option activity, additional disclosures
Intrinsic value of options exercised	17,629	2,769
Amount of cash received from exercise of options	58,986	12,304
Actual tax benefit realized for tax deductions from option exercises	6,436
Restricted Stock [Member]
Unrecognized compensation expense
Unrecognized compensation cost	32,752
Estimated weighted-average amortization period for unrecognized compensation cost (in months)	32
Restricted stock activity, restricted stock
Balance at the beginning of the period (in shares)	934,505
Granted (in shares)	565,699
Vested (in shares)	-371,458
Canceled (in shares)	-21,433
Balance at the end of the period (in shares)	1,107,313
Restricted stock activity, weighted-average grant date fair value
Balance at the beginning of the period (in dollars per share)	$35.83
Granted (in dollars per share)	$40.52
Vested (in dollars per share)	$40.37
Canceled (in dollars per share)	$43.75
Balance at the end of the period (in dollars per share)	$36.55
Restricted Stock and Performance Units, Additional Disclosure
Actual tax benefit realized from vested restricted stock grants	5,375
Fair value of restricted stock grants that vested	$14,996	$10,297

Commitments_and_Contingencies_

Commitments and Contingencies Details (Details) (USD $)	Sep. 28, 2013
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]
Loss Contingency, Estimate of Possible Loss	$1,500

Business_Segment_Information_D

Business Segment Information (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
	segments
Segment Reporting [Abstract]
Number of reportable segments	2
Business segment information
Net sales	$292,129	$278,686	$876,300	$849,390
Operating income	40,843	37,682	126,794	130,696
Depreciation and amortization			67,336	60,617
Capital expenditures			25,319	33,795
Unallocated corporate overhead
Stock-based compensation expense	6,047	5,241	18,232	15,828
Depreciation expense			54,444	47,181
Research Models [Member]
Business segment information
Net sales	92,969	90,877	294,993	293,575
Research Model Services [Member]
Business segment information
Net sales	52,105	53,400	156,661	163,247
Other Products [Member]
Business segment information
Net sales	28,331	22,207	83,213	66,425
Total Segments [Member]
Business segment information
Operating income	58,896	54,364	182,824	184,356
Research Models and Services [Member]
Business segment information
Net sales	173,405	166,484	534,867	523,247
Gross margin	65,710	65,902	221,916	224,364
Operating income	40,260	43,389	145,193	158,398
Depreciation and amortization	16,876	9,670	37,378	27,697
Capital expenditures	6,110	7,423	16,464	27,892
Preclinical Services [Member]
Business segment information
Net sales	118,724	112,202	341,433	326,143
Gross margin	34,216	27,358	84,791	76,693
Operating income	18,636	10,975	37,631	25,958
Depreciation and amortization	10,039	10,880	29,957	32,920
Capital expenditures	2,986	2,819	8,855	5,903
Unallocated Corporate Overhead [Member]
Business segment information
Operating income	-18,053	-16,682	-56,030	-53,660
Unallocated corporate overhead
Stock-based compensation expense	3,260	2,827	9,927	8,512
U.S. retirement plans	1,275	1,276	3,617	3,662
Audit, tax and related expenses	811	842	3,135	2,133
Salary and bonus	5,831	4,813	16,057	14,602
Global IT	3,002	3,285	8,448	9,501
Employee health, long-term disability and fringe benefit expense	-1,470	-2,248	-898	-1,395
Consulting and professional services	1,439	1,061	3,443	3,581
Depreciation expense	1,570	1,554	4,712	4,693
Other general unallocated corporate expenses	2,335	3,272	7,589	8,371
Total unallocated corporate overhead costs	$18,053	$16,682	$56,030	$53,660

Discontinued_Operations_Detail

Discontinued Operations (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012	Dec. 29, 2012	Mar. 26, 2011
Operating results from discontinued operations
Facility lease payments			$11,677
Net sales	0	0	0	0
Income (loss) from operatoins of discontinued businesses, before income taxes	-172	49	-1,894	221
Provision (benefit) for income taxes	-59	231	-711	284
Income (loss) from operations of discontinued businesses, net of taxes	-113	-182	-1,183	-63
Discontinued Operation, Provision for Loss (Gain) on Disposal, before Income Tax			1,316
Assets and liabilities of discontinued operations
Current assets	758		758		495
Long-term assets	3,326		3,326		3,328
Total assets	4,084		4,084		3,823
Current liabilities	1,944		1,944		1,802
Long-term liabilities of discontinued businesses	8,531		8,531		8,795
Total liabilities	10,475		10,475		10,597
Guarantor Obligations, Current Carrying Value	$10,375		$10,375			$2,994

Business_Acquisitions_Business

Business Acquisitions Business Acquisition Details (Details) (USD $)	9 Months Ended		3 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013	Jan. 04, 2013	Dec. 28, 2013
			EMD Singapore [Member]
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired		75.00%
Business Acquisition, Cost of Acquired Entity, Purchase Price	$26,890		$5,000
Business Acquisition, Effective Date of Acquisition	4-Jan-13

Business_Acquisitions_Finite_L

Business Acquisitions Finite Lived Intangible Assets (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2013
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Asset, Amount	$16,281
Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Asset, Amount	14,292
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	11 years 8 months 12 days
Royalty Agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Asset, Amount	1,829
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	1 year 3 months 18 days
Noncompete Agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Asset, Amount	$160
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	2 years 9 months 18 days

Business_Acquisitions_Purchase

Business Acquisitions Purchase Price Allocation (Details) (USD $)	Sep. 28, 2013	Jan. 04, 2013	Dec. 29, 2012
In Thousands, unless otherwise specified
Business Acquisition [Line Items]
Business Acquisition, Purchase Price Allocation, Current Assets, Cash and Cash Equivalents		$2,671
Business Acquisition, Purchase Price Allocation, Current Assets, Receivables		3,092
Business Acquisition, Purchase Price Allocation, Tangible Assets		10,468
Business Acquisition, Purchase Price Allocation, Noncurrent Assets, Description		2,242
Business Acquisition, Purchase Price Allocation, Intangible Assets Other than Goodwill		16,281
Goodwill	229,271	19,096	208,609
Business Acquisition, Purchase Price Allocation, Current Liabilities, Description		-11,790
Business Acquisition, Purchase Price Allocation, Noncurrent Liabilities, Description		-6,207
Business Acquisition, Purchase Price Allocation, Noncontrolling Interest		-8,963
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net		$24,219

Business_Acquisitions_Noncontr

Business Acquisitions Noncontrolling Interest (Details)	Jan. 04, 2013
Noncontrolling Interest [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	25.00%