Summary of Changes in Accumulated Other Comprehensive Income (Loss) by Component (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period			$ 87,711
Net change related to other comprehensive income (loss)	$ (754)	$ 189	(1,780)	$ (953)
Balance, end of period	79,239	83,491	79,239	83,491
Derivatives
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period	21	595	134	352
Unrealized gains (losses), net of tax	15	(60)	30	424
Tax expense included in provision for income taxes	0	2	2	8
Amounts reclassified from accumulated other comprehensive income	(8)	(165)	(136)	(406)
Net change related to other comprehensive income (loss)	7	(225)	(106)	18
Balance, end of period	28	370	28	370
Derivatives | Revenue
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification adjustments for gains	(8)	(167)	(138)	(414)
Investments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period	659	2,030	1,825	2,941
Unrealized gains (losses), net of tax	(644)	571	(961)	367
Tax expense included in provision for income taxes	145	273	602	654
Amounts reclassified from accumulated other comprehensive income	(372)	(506)	(1,221)	(1,213)
Net change related to other comprehensive income (loss)	(1,016)	65	(2,182)	(846)
Balance, end of period	(357)	2,095	(357)	2,095
Investments | Other income (expense), net
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification adjustments for gains	(517)	(779)	(1,823)	(1,867)
Translation adjustments and other
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period	(1,079)	(1,973)	(1,332)	(1,499)
Net change related to other comprehensive income (loss)	255	349	508	(125)
Balance, end of period	(824)	(1,624)	(824)	(1,624)
Accumulated other comprehensive income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period	(399)	652	627	1,794
Net change related to other comprehensive income (loss)	(754)	189	(1,780)	(953)
Balance, end of period	$ (1,153)	$ 841	$ (1,153)	$ 841