Gains (Losses) on Fair Value Hedges and Related Hedged Items (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Foreign Exchange Contracts
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives	$ 129	$ (260)	$ 140	$ (224)
Hedged items	(81)	288	(19)	298
Total amount of ineffectiveness	48	28	121	74
Equity Contracts
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives	0	126	0	(181)
Hedged items	0	(126)	0	181
Total amount of ineffectiveness	0	0	0	0
Amount of equity contracts excluded from effectiveness assessment	$ 0	$ 0	$ 0	$ 60

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
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Amount of gain (loss)recognized in the income statement from the hedging ineffectiveness of a fair value hedge.

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