Revenue Accounting for Contracts / Accounting for Joint Ventures (Pass-Through Costs Included in Revenues) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2017	Jul. 01, 2016	Jun. 30, 2017	Jul. 01, 2016
Revenue Accounting For Contracts Accounting For Joint Ventures [Abstract]
Pass-through costs included in revenues	$ 628,070	$ 616,160	$ 1,861,615	$ 1,887,620