Debt Obligations - Repurchase Agreement (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2024	Dec. 31, 2023
Repurchase Agreement Counterparty [Line Items]
Outstanding Principal	$ 3,024,534
Morgan Stanley
Repurchase Agreement Counterparty [Line Items]
Outstanding Principal	862,878	$ 483,339
Net Counterparty Exposure	$ 272,862	$ 203,080
Percent of Stockholders' Equity	20.10%	14.50%
Weighted Average Life (Years)	2 years	1 year 7 months 6 days
Wells Fargo
Repurchase Agreement Counterparty [Line Items]
Outstanding Principal	$ 608,821	$ 646,559
Net Counterparty Exposure	$ 260,621	$ 248,891
Percent of Stockholders' Equity	19.20%	17.70%
Weighted Average Life (Years)	2 years 6 months	2 years 8 months 12 days
Total
Repurchase Agreement Counterparty [Line Items]
Outstanding Principal	$ 1,471,699
Net Counterparty Exposure	$ 533,482
Percent of Stockholders' Equity	39.30%
Weighted Average Life (Years)	2 years 2 months 12 days
KREF Lending IX
Repurchase Agreement Counterparty [Line Items]
Outstanding Principal		$ 696,605
Net Counterparty Exposure		$ 172,462
Percent of Stockholders' Equity		12.30%
Weighted Average Life (Years)		3 years 1 month 6 days
Goldman Sachs
Repurchase Agreement Counterparty [Line Items]
Outstanding Principal		$ 347,329
Net Counterparty Exposure		$ 170,236
Percent of Stockholders' Equity		12.10%
Weighted Average Life (Years)		2 years 10 months 24 days
Total
Repurchase Agreement Counterparty [Line Items]
Outstanding Principal		$ 2,173,832
Net Counterparty Exposure		$ 794,669
Percent of Stockholders' Equity		56.60%
Weighted Average Life (Years)		2 years 7 months 6 days

Repurchase Agreement Counterparty, Amount at Risk, Percent of Stockholders' Equity

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-4

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- Definition

The amount at risk under repurchase agreements is defined as the excess of carrying amount (or market value, if higher than the carrying amount or if there is no carrying amount) of the securities or other assets sold under agreement to repurchase, including accrued interest plus any cash or other assets on deposit to secure the repurchase obligation, over the amount of the repurchase liability (adjusted for accrued interest).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481420/860-30-50-9

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(m)(1)(iii))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

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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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- Definition

Weighted average maturity (weighted by amount of the agreement) of repurchase agreements with the counterparty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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