Consolidated Statements of Comprehensive (Loss) Income (Parenthetical) - USD ($)	3 Months Ended		6 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Unrealized holding gains (losses) on securities, income tax expense (benefit)	$ 8,000,000	$ 2,000,000	$ 2,000,000	$ (8,000,000)
Benefit plan adjustments, income tax (benefit) expense	0	5,000,000	(2,000,000)	8,000,000
Share of other comprehensive (loss) income from equity affiliates, income tax expense	$ 0	$ 4,000,000	$ 0	$ 5,000,000