Fair Value - Financial Assets Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Assets:
Real estate securities, available for sale	$ 36,250	$ 252,824
Mortgage loans held in securitization trusts, at fair value	1,839,390	1,872,970
Other assets - derivative assets	1,981	4,122
Liabilities:
Mortgage obligations issued by securitization trusts, at fair value	1,770,924	1,762,914
Other liabilities - derivative liabilities	37	19,133
Recurring basis
Assets:
Investments in unconsolidated ventures - PE Investments	7,093	10,283
Real estate securities, available for sale	36,250	252,824
Mortgage loans held in securitization trusts, at fair value	1,839,390	1,872,970
Other assets - derivative assets	1,981	4,122
Liabilities:
Mortgage obligations issued by securitization trusts, at fair value	1,770,924	1,762,914
Other liabilities - derivative liabilities	37	19,133
Recurring basis \| Level 1
Assets:
Investments in unconsolidated ventures - PE Investments	0	0
Real estate securities, available for sale	0	0
Mortgage loans held in securitization trusts, at fair value	0	0
Other assets - derivative assets	0	0
Liabilities:
Mortgage obligations issued by securitization trusts, at fair value	0	0
Other liabilities - derivative liabilities	0	0
Recurring basis \| Level 2
Assets:
Investments in unconsolidated ventures - PE Investments	124	1,425
Real estate securities, available for sale	36,250	252,824
Mortgage loans held in securitization trusts, at fair value	0	0
Other assets - derivative assets	1,981	4,122
Liabilities:
Mortgage obligations issued by securitization trusts, at fair value	1,770,924	1,762,914
Other liabilities - derivative liabilities	37	19,133
Recurring basis \| Level 3
Assets:
Investments in unconsolidated ventures - PE Investments	6,969	8,858
Real estate securities, available for sale	0	0
Mortgage loans held in securitization trusts, at fair value	1,839,390	1,872,970
Other assets - derivative assets		0
Liabilities:
Mortgage obligations issued by securitization trusts, at fair value	0	0
Other liabilities - derivative liabilities	$ 0	$ 0

Mortgage Loans, Held in Trust, at Fair Value

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- Definition

Mortgage Loans on Real Estate, Held in Trust, at Fair Value

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- Definition

Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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