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Reportable Segments - Revenue By Client Sector (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jul. 01, 2018 | Jul. 02, 2017 | Jul. 01, 2018 | Jul. 02, 2017
Revenue by client sector |  |  |  |
Revenue | $ 764,795 | $ 685,539 | $ 2,224,805 | $ 2,018,171
U.S. state and local government |  |  |  |
Revenue by client sector |  |  |  |
Revenue | 103,169 | 83,716 | 359,828 | 250,392
U.S. federal government |  |  |  |
Revenue by client sector |  |  |  |
Revenue | 245,982 | 224,343 | 719,181 | 665,086
U.S. commercial |  |  |  |
Revenue by client sector |  |  |  |
Revenue | 208,507 | 199,065 | 595,691 | 554,707
International |  |  |  |
Revenue by client sector |  |  |  |
Revenue | $ 207,137 | $ 178,415 | $ 550,105 | $ 547,986

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