Real Estate Securities - Narrative (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020 USD ($) security investment	Dec. 31, 2019 USD ($) security investment
Debt Securities, Available-for-sale [Line Items]
Real estate securities amortized cost	$ 509,745	$ 387,294
Number of securities with unrealized loss \| security	2	2
CMBS
Debt Securities, Available-for-sale [Line Items]
Number of investments held \| investment	29	21
Real estate securities amortized cost	$ 509,745	$ 387,294
Unrealized loss	$ 68,585	$ 979
CMBS \| Nonperforming Financial Instruments
Debt Securities, Available-for-sale [Line Items]
Number of investments held \| investment	2	2
SASB
Debt Securities, Available-for-sale [Line Items]
Weighted average contractual maturity	14 years	5 years
Real estate securities amortized cost	$ 98,511	$ 57,294
Unrealized loss	$ 8,755	$ 98
CLOs
Debt Securities, Available-for-sale [Line Items]
Weighted average contractual maturity	16 years	17 years
Real estate securities amortized cost	$ 411,234	$ 330,000
Unrealized loss	$ 59,830	$ 881

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- Definition

Number of Investments Held

+ References

No definition available.

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- Definition

Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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