Changes in Estimates (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Dec. 28, 2018	Dec. 29, 2017	Dec. 28, 2018	Dec. 29, 2017
Change in Accounting Estimate [Line Items]
Revenue recognized from performance obligations satisfied in prior periods	$ 9	$ 16	$ 16	$ 30
Contracts Accounted for under Percentage of Completion
Change in Accounting Estimate [Line Items]
Operating income (loss)	$ 2	$ (16)	$ (1)	$ (11)
Operating income (loss), per diluted share (in dollars per share)	$ 0.02	$ (0.09)		$ (0.06)
Operating income (loss), net of tax		$ (11)		$ (8)