Investment Components, Including Associated Derivatives but Excluding Held to Maturity Investments (Detail) - USD ($) $ in Millions	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2013
Cash, Cash Equivalents and Investments [Line Items]
Cost Basis	$ 119,053	$ 103,647
Unrealized Gains	4,895	5,220
Unrealized Losses	(302)	(313)
Recorded Basis	123,646	108,554
Cash and cash equivalents	6,510	5,595	$ 8,669	$ 3,804
Short-term Investments	106,730	90,931
Equity and Other Investments	10,406	12,028
Cash
Cash, Cash Equivalents and Investments [Line Items]
Cash	3,501	3,679
Unrealized Gains	0	0
Unrealized Losses	0	0
Cash	3,501	3,679
Cash and cash equivalents	3,501	3,679
Short-term Investments	0	0
Equity and Other Investments	0	0
Mutual funds
Cash, Cash Equivalents and Investments [Line Items]
Cost Basis	1,012	1,100
Unrealized Gains	0	0
Unrealized Losses	0	0
Recorded Basis	1,012	1,100
Cash and cash equivalents	1,012	1,100
Short-term Investments	0	0
Equity and Other Investments	0	0
Commercial paper
Cash, Cash Equivalents and Investments [Line Items]
Cost Basis	298	1
Unrealized Gains	0	0
Unrealized Losses	0	0
Recorded Basis	298	1
Cash and cash equivalents	298	1
Short-term Investments	0	0
Equity and Other Investments	0	0
Certificates of deposit
Cash, Cash Equivalents and Investments [Line Items]
Cost Basis	1,000	906
Unrealized Gains	0	0
Unrealized Losses	0	0
Recorded Basis	1,000	906
Cash and cash equivalents	868	776
Short-term Investments	132	130
Equity and Other Investments	0	0
U.S. government and agency securities
Cash, Cash Equivalents and Investments [Line Items]
Cost Basis	89,970	72,843
Unrealized Gains	245	76
Unrealized Losses	(11)	(30)
Recorded Basis	90,204	72,889
Cash and cash equivalents	100	39
Short-term Investments	90,104	72,850
Equity and Other Investments	0	0
Foreign government bonds
Cash, Cash Equivalents and Investments [Line Items]
Cost Basis	5,502	5,477
Unrealized Gains	10	3
Unrealized Losses	(18)	(24)
Recorded Basis	5,494	5,456
Cash and cash equivalents	731	0
Short-term Investments	4,763	5,456
Equity and Other Investments	0	0
Mortgage- and asset-backed securities
Cash, Cash Equivalents and Investments [Line Items]
Cost Basis	4,789	4,899
Unrealized Gains	21	23
Unrealized Losses	(2)	(6)
Recorded Basis	4,808	4,916
Cash and cash equivalents	0	0
Short-term Investments	4,808	4,916
Equity and Other Investments	0	0
Corporate notes and bonds
Cash, Cash Equivalents and Investments [Line Items]
Cost Basis	6,509	7,192
Unrealized Gains	110	97
Unrealized Losses	(35)	(37)
Recorded Basis	6,584	7,252
Cash and cash equivalents	0	0
Short-term Investments	6,584	7,252
Equity and Other Investments	0	0
Municipal securities
Cash, Cash Equivalents and Investments [Line Items]
Cost Basis	285	285
Unrealized Gains	57	35
Unrealized Losses	0	(1)
Recorded Basis	342	319
Cash and cash equivalents	0	0
Short-term Investments	342	319
Equity and Other Investments	0	0
Common and preferred stock
Cash, Cash Equivalents and Investments [Line Items]
Cost Basis	5,597	6,668
Unrealized Gains	4,452	4,986
Unrealized Losses	(236)	(215)
Recorded Basis	9,813	11,439
Cash and cash equivalents	0	0
Short-term Investments	0	0
Equity and Other Investments	9,813	11,439
Other investments
Cash, Cash Equivalents and Investments [Line Items]
Cost Basis	590	597
Unrealized Gains	0	0
Unrealized Losses	0	0
Recorded Basis	590	597
Cash and cash equivalents	0	0
Short-term Investments	(3)	8
Equity and Other Investments	$ 593	$ 589