Segment Information (Detail) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended | ||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 28, 2018 |
Sep. 28, 2018 |
Jun. 29, 2018 |
Mar. 30, 2018 |
Dec. 29, 2017 |
Sep. 29, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 28, 2018 |
Dec. 29, 2017 |
Dec. 30, 2016 |
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Segment Reporting Information [Line Items] | ||||||||||||||||
Revenues | $ 92,143 | $ 95,302 | $ 95,621 | $ 96,457 | $ 88,282 | $ 87,555 | $ 87,840 | $ 84,122 | $ 379,523 | [1] | $ 347,799 | [1] | $ 315,076 | [1] | ||
Operating Income | $ 26,786 | $ 20,594 | $ 22,478 | $ 21,598 | $ 17,795 | $ 19,305 | $ 20,317 | $ 14,634 | 91,456 | 72,051 | 61,911 | |||||
Capital Expenditures | 17,381 | 4,725 | 14,393 | |||||||||||||
Depreciation and Amortization | 6,292 | 6,285 | 6,131 | |||||||||||||
Operating segments | ||||||||||||||||
Segment Reporting Information [Line Items] | ||||||||||||||||
Operating Income | 124,131 | 115,791 | 99,144 | |||||||||||||
Capital Expenditures | 4,727 | 3,866 | 4,433 | |||||||||||||
Depreciation and Amortization | 4,606 | 4,628 | 4,610 | |||||||||||||
Engineering and Other Scientific | ||||||||||||||||
Segment Reporting Information [Line Items] | ||||||||||||||||
Revenues | 306,265 | 277,603 | 248,297 | |||||||||||||
Operating Income | 100,307 | 93,451 | 80,494 | |||||||||||||
Capital Expenditures | 4,528 | 3,648 | 4,309 | |||||||||||||
Depreciation and Amortization | 4,435 | 4,449 | 4,429 | |||||||||||||
Environmental and Health | ||||||||||||||||
Segment Reporting Information [Line Items] | ||||||||||||||||
Revenues | 73,258 | 70,196 | 66,779 | |||||||||||||
Operating Income | 23,824 | 22,340 | 18,650 | |||||||||||||
Capital Expenditures | 199 | 218 | 124 | |||||||||||||
Depreciation and Amortization | 171 | 179 | 181 | |||||||||||||
Corporate | ||||||||||||||||
Segment Reporting Information [Line Items] | ||||||||||||||||
Operating Income | (32,675) | (43,740) | (37,233) | |||||||||||||
Capital Expenditures | 12,654 | 859 | 9,960 | |||||||||||||
Depreciation and Amortization | $ 1,686 | $ 1,657 | $ 1,521 | |||||||||||||
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