Summary of Changes in Accumulated Other Comprehensive Income (Loss) by Component (Detail) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period	$ 87,711	$ 83,090
Net change related to other comprehensive income (loss)	(2,856)	(1,167)	$ (728)
Balance, end of period	82,718	87,711	83,090
Derivatives
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period	134	352	590
Unrealized gains (losses), net of tax	218	328	351
Tax expense included in provision for income taxes	6	9	36
Amounts reclassified from accumulated other comprehensive income	(179)	(546)	(589)
Net change related to other comprehensive income (loss)	39	(218)	(238)
Balance, end of period	173	134	352
Derivatives | Revenue
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification adjustments for gains	(185)	(555)	(625)
Investments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period	1,825	2,941	3,169
Unrealized gains (losses), net of tax	(1,146)	517	219
Tax expense included in provision for income taxes	738	880	241
Amounts reclassified from accumulated other comprehensive income	(1,571)	(1,633)	(447)
Net change related to other comprehensive income (loss)	(2,717)	(1,116)	(228)
Balance, end of period	(892)	1,825	2,941
Investments | Other income (expense), net
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification adjustments for gains	(2,309)	(2,513)	(688)
Translation adjustments and other
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period	(1,332)	(1,499)	(1,237)
Net change related to other comprehensive income (loss)	(178)	167	(262)
Balance, end of period	(1,510)	(1,332)	(1,499)
Accumulated other comprehensive income (loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period	627	1,794	2,522
Net change related to other comprehensive income (loss)	(2,856)	(1,167)	(728)
Cumulative effect of accounting change	42	0	0
Balance, end of period	$ (2,187)	$ 627	$ 1,794