Fair Value Disclosures - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (Parenthetical) $ in Millions	Jun. 30, 2019 USD ($)
Significant Other Observable Inputs (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Non marketable equity security	$ 60

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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