Unconsolidated Entities - Summary of Investments in and Advances to our Unconsolidated Entities (Parenthetical) (Detail)	Dec. 31, 2020 Venture
Other Ventures [Member] \| Liberty Transaction [Member]
Schedule Of Equity Method Investments [Line Items]
Ventures	8

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.

No definition available.

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