Adoption of New Standard Impact on Previously Reported Quarterly Results (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended				9 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015	Jun. 30, 2015
Income statements:
Provision for income taxes	$ 1,280	$ 837	$ 611	$ 1,532	$ 2,728	$ 4,875
Net income	$ 3,756	$ 5,018	$ 4,902	$ 4,985	$ 13,676	$ 15,388
Basic earnings per share	$ 0.48	$ 0.63	$ 0.61	$ 0.61	$ 1.72	$ 1.87
Diluted earnings per share	$ 0.47	$ 0.62	$ 0.61	$ 0.61	$ 1.70	$ 1.86
Diluted weighted average shares outstanding	7,985	8,051	8,084	8,237	8,041	8,293
Cash flows statements:
Net cash from operations	$ 10,367	$ 5,618	$ 8,876	$ 9,601	$ 24,861	$ 22,819
Net cash used in financing	(4,916)	(518)	(3,930)	$ (3,096)	(9,364)	$ (6,064)
Balance sheets:
Common stock and paid-in capital	68,012	67,977	67,811		68,012		$ 68,465
Retained earnings	$ 4,954	7,030	7,896		$ 4,954		$ 9,096
As reported
Income statements:
Provision for income taxes		857	893
Net income		$ 4,998	$ 4,620
Basic earnings per share		$ 0.63	$ 0.58
Diluted earnings per share		$ 0.62	$ 0.57
Diluted weighted average shares outstanding		8,028	8,066
Cash flows statements:
Net cash from operations		$ 5,598	$ 8,594
Net cash used in financing		(498)	(3,648)
Balance sheets:
Common stock and paid-in capital		68,279	68,093
Retained earnings		$ 6,728	$ 7,614