Gains (Losses) on Fair Value Hedges and Related Hedged Items (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Foreign Exchange Contracts
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives	$ (260)	$ (248)	$ (224)	$ 389
Hedged items	288	257	298	(349)
Total amount of ineffectiveness	28	9	74	40
Equity Contracts
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives	126	(19)	(181)	(36)
Hedged items	(126)	19	181	36
Total amount of ineffectiveness	0	0	0	0
Amount of equity contracts excluded from effectiveness assessment	$ 0	$ (25)	$ 60	$ (29)

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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- Definition

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Net gain (loss) relating to components of the gain (loss) on the fair value hedging instrument excluded from the assessment of fair value hedge effectiveness. Recognized in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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- Definition

Amount of gain (loss)recognized in the income statement from the hedging ineffectiveness of a fair value hedge.

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