Repurchase Agreements - Assets Pledged as Collateral (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financial Instruments Owned and Pledged as Collateral [Line Items]
Outstanding Borrowings	$ 2,352,102	$ 1,543,577
Fair Value of Collateral Pledged	2,839,379	1,784,191
Amortized Cost Of Collateral Pledged	2,643,541	1,672,486
Agency RMBS
Financial Instruments Owned and Pledged as Collateral [Line Items]
Outstanding Borrowings	812,742	925,230
Fair Value of Collateral Pledged	865,765	978,357
Amortized Cost Of Collateral Pledged	864,428	1,014,284
Agency CMBS
Financial Instruments Owned and Pledged as Collateral [Line Items]
Outstanding Borrowings	133,184	0
Fair Value of Collateral Pledged	139,317	0
Amortized Cost Of Collateral Pledged	140,118	0
Non-Agency RMBS
Financial Instruments Owned and Pledged as Collateral [Line Items]
Outstanding Borrowings	594,286	88,730
Fair Value of Collateral Pledged	797,784	117,958
Amortized Cost Of Collateral Pledged	785,952	118,414
CMBS
Financial Instruments Owned and Pledged as Collateral [Line Items]
Outstanding Borrowings	811,890	529,617
Fair Value of Collateral Pledged	1,036,513	687,876
Amortized Cost Of Collateral Pledged	853,043	539,788
Consolidated SLST \| Agency RMBS
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities owned and pledged as collateral, fair value	26,200
Consolidated SLST \| Non-Agency RMBS
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities owned and pledged as collateral, fair value	214,800
Consolidated K-Series \| Agency CMBS
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities owned and pledged as collateral, fair value	88,400
Consolidated K-Series \| CMBS
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities owned and pledged as collateral, fair value	$ 848,200	$ 543,000

Amortized Cost Of Collateral Pledged.

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- Definition

The fair value as of the balance sheet date of financial instruments and other positions owned by the entity and pledged to counterparties as collateral, including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities.

+ References

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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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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions.

+ References

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