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Reportable Segments - Revenue By Client Sector (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Apr. 02, 2017 | Mar. 27, 2016 | Apr. 02, 2017 | Mar. 27, 2016
Revenue by client sector |  |  |  |
Revenue | $ 663,781 | $ 627,384 | $ 1,332,632 | $ 1,188,092
U.S. federal government |  |  |  |
Revenue by client sector |  |  |  |
Revenue | 218,110 | 178,015 | 440,744 | 343,037
International |  |  |  |
Revenue by client sector |  |  |  |
Revenue | 197,114 | 206,902 | 369,571 | 342,708
U.S. state and local government |  |  |  |
Revenue by client sector |  |  |  |
Revenue | 83,181 | 68,086 | 166,676 | 139,802
U.S. commercial |  |  |  |
Revenue by client sector |  |  |  |
Revenue | $ 165,376 | $ 174,381 | $ 355,641 | $ 362,545

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- Definition Aggregate revenue during the period from services rendered in the normal course of business, after deducting allowances and discounts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(d)) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 + Details
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