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Debt - Additional Information (Detail) - USD ($)	12 Months Ended
Debt - Additional Information (Detail) - USD ($)	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016	Oct. 31, 2017
Debt Instrument [Line Items]
Commercial paper	$ 0	$ 9,100,000,000
Credit facility, financial covenant	As of June 30, 2018, we were in compliance with the only financial covenant in both credit agreements, which requires us to maintain a coverage ratio of at least three times earnings before interest, taxes, depreciation, and amortization to interest expense, as defined in the credit agreements.
Credit facility, drawn	$ 0	0
Long-term debt	76,200,000,000	77,100,000,000
Long-term debt fair value	77,500,000,000	80,300,000,000
Cash paid for interest	2,400,000,000	1,600,000,000	$ 1,100,000,000
Debt issuance costs and unamortized discount	$ 658,000,000	$ 715,000,000
Credit Facility Expire on October 30th 2018
Debt Instrument [Line Items]
Credit facility				$ 5,000,000,000
Credit facility, expiration date	Oct. 30, 2018
Credit Facility Expire on October 31st 2022
Debt Instrument [Line Items]
Credit facility				$ 5,000,000,000
Credit facility, expiration date	Oct. 31, 2022
Commercial paper
Debt Instrument [Line Items]
Commercial paper, weighted average interest rate		1.01%
Commercial paper \| Lower Limit
Debt Instrument [Line Items]
Commercial paper, maturity term		25 days
Commercial paper \| Upper Limit
Debt Instrument [Line Items]
Commercial paper, maturity term		264 days