Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Dec. 29, 2017	Jun. 30, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Foreign currency translation, net of income taxes of $2 million and $1 million at December 29, 2017 and June 30, 2017, respectively	$ (92)	$ (113)
Net unrealized loss on hedging derivatives, net of income taxes of $11 million at December 29, 2017 and June 30, 2017	(16)	(17)
Unrecognized postretirement obligations, net of income taxes of $89 million at December 29, 2017 and June 30, 2017	(146)	(146)
Accumulated other comprehensive loss	(254)	(276)
Tax effect on foreign currency translation	2	1
Tax effect on unrealized loss on hedging derivatives	11	11
Tax effect on unrecognized post-retirement obligations	$ 89	89
Accumulated Foreign Currency Adjustment Attributable to Parent | Discontinued Operations, Disposed of by Sale | IT Services and CapRock
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated foreign currency translation loss reclassified to earnings, net of tax		52
Accumulated foreign currency translation loss reclassified to earnings, tax		$ 14