The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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The net result for the period of deducting operating expenses from operating revenues.

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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
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Segment and Geographic Information Financial Information by Reportable Business Segment (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 26, 2015	Sep. 26, 2015	Jun. 27, 2015	Mar. 28, 2015	Dec. 27, 2014	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Segment Reporting Information [Line Items]
Revenue	$ 353,850	$ 349,465	$ 339,573	$ 320,414	$ 329,548	$ 327,567	$ 341,179	$ 299,368	$ 1,363,302	$ 1,297,662	$ 1,165,528
Operating income	$ 52,269	$ 55,440	$ 55,735	$ 43,005	$ 40,767	$ 46,172	$ 51,025	$ 39,706	206,449	177,670	151,401
Depreciation and amortization									94,881	96,445	96,636
Capital expenditures									63,252	56,925	39,154
RMS
Segment Reporting Information [Line Items]
Revenue									473,230	507,327	511,350
Operating income									121,447	121,376	116,737
Depreciation and amortization									22,688	27,512	41,837
Capital expenditures									17,398	18,749	16,717
DSA
Segment Reporting Information [Line Items]
Revenue									612,173	538,218	432,378
Operating income									121,981	69,749	47,413
Depreciation and amortization									46,812	47,138	37,720
Capital expenditures									30,333	19,759	12,561
Manufacturing
Segment Reporting Information [Line Items]
Revenue									277,899	252,117	221,800
Operating income									74,201	78,620	61,227
Depreciation and amortization									17,967	14,092	17,079
Capital expenditures									$ 9,814	$ 15,541	$ 9,876