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Reportable Segments - Revenue by Sector (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Oct. 01, 2017 | Jul. 02, 2017 | Apr. 02, 2017 | Jan. 01, 2017 | Oct. 02, 2016 | Jun. 26, 2016 | Mar. 27, 2016 | Dec. 27, 2015 | Oct. 01, 2017 | Oct. 02, 2016 | Sep. 27, 2015
Revenue by client sector |  |  |  |  |  |  |  |  |  |  |
Threshold percentage for disclosure of revenue from a single client |  |  |  |  |  |  |  |  | 10.00% | 10.00% | 10.00%
Revenue | $ 735,188 | $ 685,539 | $ 663,781 | $ 668,851 | $ 728,508 | $ 666,869 | $ 627,384 | $ 560,708 | $ 2,753,360 | $ 2,583,469 | $ 2,299,321
International |  |  |  |  |  |  |  |  |  |  |
Revenue by client sector |  |  |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  |  |  | 734,519 | 724,918 | 564,882
U.S. commercial |  |  |  |  |  |  |  |  |  |  |
Revenue by client sector |  |  |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  |  |  | 764,643 | 763,443 | 736,815
U.S. federal government |  |  |  |  |  |  |  |  |  |  |
Revenue by client sector |  |  |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  |  |  | 901,136 | 784,368 | 709,600
U.S. state and local government |  |  |  |  |  |  |  |  |  |  |
Revenue by client sector |  |  |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  |  |  | $ 353,062 | $ 310,740 | $ 288,024

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