Secured Financing Agreements - Schedule of Debt (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Principal Balance	$ 435,490
Total/weighted average
Debt Instrument [Line Items]
Maximum Facility Size	682,000	$ 682,000
Principal Balance	435,490	473,615
Carrying Value	$ 433,385	$ 471,521
Coupon Rate	6.76%	6.34%
Remaining maturity (years)	1 year 3 months 18 days	1 year 6 months
Principal Balance	$ 590,832	$ 640,972
Total/weighted average \| SOFR \| Minimum
Debt Instrument [Line Items]
Coupon Rate	1.83%	1.83%
Total/weighted average \| SOFR \| Maximum
Debt Instrument [Line Items]
Coupon Rate	2.51%	2.51%
Master Repurchase Facility \| Citibank Master Repurchase Facility
Debt Instrument [Line Items]
Maximum Facility Size	$ 215,000	$ 192,000
Principal Balance	150,101	144,437
Carrying Value	$ 149,845	$ 143,887
Coupon Rate	6.83%	6.48%
Remaining maturity (years)	10 months 24 days	1 year 1 month 6 days
Principal Balance	$ 205,380	$ 198,254
Master Repurchase Facility \| UBS Master Repurchase Facility
Debt Instrument [Line Items]
Maximum Facility Size	192,000	215,000
Principal Balance	133,108	150,647
Carrying Value	$ 132,680	$ 150,360
Coupon Rate	6.80%	6.34%
Remaining maturity (years)	9 months 18 days	1 year 1 month 6 days
Principal Balance	$ 182,530	$ 205,234
Master Repurchase Facility \| BMO Facility
Debt Instrument [Line Items]
Maximum Facility Size	150,000	150,000
Principal Balance	84,855	111,105
Carrying Value	$ 84,296	$ 110,473
Coupon Rate	6.73%	6.22%
Remaining maturity (years)	2 years	2 years 2 months 12 days
Principal Balance	$ 113,745	$ 148,476
Asset Specific Financing \| Wells Fargo Master Repurchase Facility
Debt Instrument [Line Items]
Maximum Facility Size	125,000	125,000
Principal Balance	67,426	67,426
Carrying Value	$ 66,564	$ 66,801
Coupon Rate	6.57%	6.23%
Remaining maturity (years)	1 year 10 months 24 days	2 years 1 month 6 days
Principal Balance	$ 89,177	$ 89,008

Assets Sold Under Agreements To Repurchase, Authorized Amount

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- Definition

Assets Sold Under Agreements To Repurchase, Principal Amount

+ References

No definition available.

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- Definition

Carrying amount of assets sold under agreements to repurchase when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under repurchase agreements exceeds 10 percent of total assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(m)(1)(i))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(m)(1)(ii)(A)(i))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

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- Definition

Interest rate on the amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets.

+ References

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- Definition

Amount of assets pledged to secure a debt instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823

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- Definition

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

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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