Share Repurchases (Detail) - USD ($) shares in Millions, $ in Millions	3 Months Ended												12 Months Ended
	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Share Repurchases [Line Items]
Shares of common stock repurchased													99	170	294
Value of common stock repurchased													$ 8,600	$ 10,283	$ 14,800
Share Repurchase Program 2016
Share Repurchases [Line Items]
Shares of common stock repurchased	21	34	22	22	23	25
Value of common stock repurchased	$ 2,100	$ 3,100	$ 1,800	$ 1,600	$ 1,600	$ 1,600
Share Repurchase Program 2013
Share Repurchases [Line Items]
Shares of common stock repurchased							59	63	70	69	66	89
Value of common stock repurchased							$ 3,533	$ 3,550	$ 3,600	$ 3,600	$ 3,600	$ 4,000