Fair Value of Financial Instruments - Financial Instruments Not Measured at Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Allowance for loan losses	$ 21,702	$ 921
Commercial mortgage loans, held-for-sale	9,619	0
Carrying Amount \| Level III
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Commercial mortgage loans, held-for-investment	2,672,300	2,762,963
Collateralized loan obligations	1,739,009	1,803,185
Mortgage Note Payable	40,167	29,167
Allowance for loan losses	21,700	900
Commercial mortgage loans, held-for-sale	9,600
Fair Value \| Level III
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Commercial mortgage loans, held-for-investment	2,673,611	2,784,650
Collateralized loan obligations	1,610,761	1,822,386
Mortgage Note Payable	$ 40,167	$ 29,167

Commercial Mortgages, Held-for-sale

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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.

+ References

No definition available.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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Fair value portion of contractual obligation to pay money on demand or on fixed or determinable dates.

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Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as held-to-maturity.

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- Definition

Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611

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