Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net change in the fair value of cash flow hedges, income tax expense	$ 0		$ 1
Unrealized holding gains on securities, income tax expense		$ 1		$ 3
Benefit plan adjustments, income tax expense (benefit)	(1)	(2)	2	(4)
Share of other comprehensive income from equity affiliates, income tax expense	$ 0	$ 0	$ 0	$ 0