Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Unrealized holding gains (losses) on securities, income tax expense (benefit)	$ 5	$ 16	$ (7)	$ 6
Benefit plan adjustments, income tax expense (benefit)	2	4	6	8
Share of other comprehensive income from equity affiliates, income tax (expense) benefit	$ 1	$ 3	$ (1)	$ 1