Commitments and Contingencies - Schedule of Principal Debt Repayments (Parenthetical) (Detail) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Non-consolidated senior interests excluded from contractual obligations	$ 688.5
Securitized debt obligations excluded from contractual obligations	$ 1,200.0
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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