Financings - Collateral Positions (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Collateral Positions
Assets pledged	$ 5,207	$ 12,960
Repurchase Agreements
Collateral Positions
Assets pledged	787,100	682,900
Assets pledged- fair value	790,263	684,675
Accrued interest	4,091	3,475
Assets pledged and accrued interest	794,354	688,150
Repurchase Agreements \| Agency RMBS
Collateral Positions
Assets pledged	1,172	1,708
Accrued interest	19	49
Assets pledged and accrued interest	1,191	1,757
Repurchase Agreements \| Non-Agency CMBS
Collateral Positions
Assets pledged	107,624	152,275
Accrued interest	504	649
Assets pledged and accrued interest	108,128	152,924
Repurchase Agreements \| Non-Agency RMBS
Collateral Positions
Assets pledged	66,555	25,382
Accrued interest	343	160
Assets pledged and accrued interest	66,898	25,542
Repurchase Agreements \| Residential Whole Loans
Collateral Positions
Assets pledged	453,447	97,566
Accrued interest	2,674	543
Assets pledged and accrued interest	456,121	98,109
Repurchase Agreements \| Residential Bridge Loans
Collateral Positions
Assets pledged	5,207	12,960
Accrued interest	91	180
Assets pledged and accrued interest	5,298	13,140
Repurchase Agreements \| Commercial Loans
Collateral Positions
Assets pledged	101,459	310,523
Accrued interest	360	1,850
Assets pledged and accrued interest	101,819	312,373
Repurchase Agreements \| Membership Interest
Collateral Positions
Assets pledged	0	33,690
Accrued interest	0	0
Assets pledged and accrued interest	0	33,690
Repurchase Agreements \| Other securities
Collateral Positions
Assets pledged	51,648	48,754
Accrued interest	100	44
Assets pledged and accrued interest	51,748	48,798
Repurchase Agreements \| Cash
Collateral Positions
Assets pledged- fair value	3,151	1,817
Accrued interest	0	0
Assets pledged and accrued interest	$ 3,151	$ 1,817

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226013-175313

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