Variable Interest Entities - Additional Information (Detail) - 2018 Single Asset Securitization $ in Millions	3 Months Ended
Sep. 30, 2018 USD ($)
Variable Interest Entity [Line Items]
Loan contributed to securitization	$ 517.5
Subordinate risk retention interest notional amount	1,000.0
Subordinate position	$ 99.0

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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