Equity - Summary of Changes in Equity (Detail) - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Equity [Abstract]
Balance, beginning of period	$ 9,291	$ 10,789
Cumulative impact of revenue standard adoption	10	0
Net income	101	68
Other comprehensive (loss) income	(75)	112
Dividends	(59)	(59)
Other	(7)	3
Balance, end of period	9,261	10,913
Balance, beginning of period	1,186	284
Cumulative impact of revenue standard adoption	10	0
Net income	27	19
Other comprehensive (loss) income	(28)	4
Dividends	(23)	(21)
Other	(3)	(3)
Balance, end of period	1,169	283
Balance, beginning of period	10,477	11,073
Cumulative impact of revenue standard adoption	20	0
Net income	128	87
Other comprehensive (loss) income	(103)	116
Dividends	(82)	(80)
Other	(10)	0
Balance, end of period	$ 10,430	$ 11,196