Secured Borrowings (Details) $ in Millions	1 Months Ended
Oct. 31, 2017 fund	Sep. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Schedule of Capitalization, Long-term Debt [Line Items]
Number of legacy funds included in sale of Certificates \| fund	6
Legacy funds transferred that did not meet the definition of participating interests \| fund	2
Secured borrowings - amount originally sold to investor		$ 105.6	$ 232.4
Fair value of credit support agreement		2.7	2.8
Secured Borrowings \| Loans Held for Investment
Schedule of Capitalization, Long-term Debt [Line Items]
Loans pledged as collateral		$ 108.0	$ 242.7

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- Definition

Legacy Funds with Participations Sold that were not Participating Interests by Definition

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- Definition

Number of Legacy Funds Included in Sale of Certificates

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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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