Additional Financial Information - Components of Other, Net Included in Statement of Operations (Detail) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
		Dec. 31, 2016	Jun. 30, 2018		Jun. 30, 2017		Jun. 30, 2016
Components of Other Income (Expense) [Line Items]
Loss on the Transaction	[1]		$ (337)		$ 0		$ 0
Gain on sale of cost method investments			32		0		0
Impairment of marketable securities and cost method investments	[2]		(33)		(21)		(21)
Other			13		46		39
Total Other, net			(325)		132		18
REA Group [Member]
Components of Other Income (Expense) [Line Items]
Gain on sale of REA Group's European business		$ 120	$ 0	[3]	$ 107	[3]	$ 0	[3]

[1] See Note 3-Acquisitions, Disposals and Other Transactions.

[2] See Note 6-Investment.

[3] The Company recognized a pre-tax gain of $107 million for the fiscal year ended June 30, 2017 related to REA Group's sale of its European business. See Note 3-Acquisitions, Disposals and Other Transactions.