Commitments and Contingencies - Schedule of Principal Debt Repayments (Parenthetical) (Detail) $ in Millions	6 Months Ended
Jun. 30, 2020 USD ($)
Debt Instrument [Line Items]
Non-consolidated senior interests excluded from contractual obligations	$ 739.6
Securitized debt obligations excluded from contractual obligations	$ 2,300.0
Debt Instrument Amortization Percentage	1.00%

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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