Segment Information - Revenue Per Significant Product or Service (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 26, 2015 |
Sep. 27, 2014 |
Sep. 26, 2015 |
Sep. 27, 2014 |
|
| Segment Reporting Information [Line Items] | ||||
| Revenue | $ 349,465 | $ 327,567 | $ 1,009,452 | $ 968,114 |
| Operating segments | Research Models and Services | ||||
| Segment Reporting Information [Line Items] | ||||
| Revenue | 118,451 | 124,021 | 358,506 | 389,636 |
| Operating segments | Discovery and Safety Assessment | ||||
| Segment Reporting Information [Line Items] | ||||
| Revenue | 158,272 | 140,862 | 451,659 | 388,614 |
| Operating segments | Microbial Solutions | ||||
| Segment Reporting Information [Line Items] | ||||
| Revenue | 39,110 | 31,834 | 105,589 | 97,879 |
| Operating segments | Other manufacturing support | ||||
| Segment Reporting Information [Line Items] | ||||
| Revenue | 33,632 | 30,850 | 93,698 | 91,985 |
| Operating segments | Manufacturing Support | ||||
| Segment Reporting Information [Line Items] | ||||
| Revenue | $ 72,742 | $ 62,684 | $ 199,287 | $ 189,864 |