Investments - Schedule of Summarized Financial Information (Parenthetical) (Detail) - Foxtel [Member] $ in Millions	6 Months Ended
Dec. 31, 2017 USD ($)
Schedule of Equity Method Investments [Line Items]
Depreciation and amortization	$ 118
Operating income before depreciation and amortization	$ 238

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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