Repurchase Agreements and Credit Facilities - Schedule of Outstanding Repurchase Agreements (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2022	Dec. 31, 2021
Repurchase Agreements and Credit Facility [Line Items]
Accrued Interest Payable	$ 1,065	$ 364
CF Repo Facility \| Commercial Mortgage Loans
Repurchase Agreements and Credit Facility [Line Items]
Committed Financing	450,000	350,000
Amount Outstanding	372,658	189,654
Accrued Interest Payable	$ 590	$ 159
Weighted Average Interest Rate	4.98%	2.16%
Weighted Average Days to Maturity	41 days	314 days
CF Repo Facility \| Commercial Mortgage Loans \| Collateral Pledged
Repurchase Agreements and Credit Facility [Line Items]
Collateral Pledged	$ 519,185	$ 260,691
JPM Repo Facility \| Commercial Mortgage Loans
Repurchase Agreements and Credit Facility [Line Items]
Committed Financing	150,000	150,000
Amount Outstanding	117,130	117,470
Accrued Interest Payable	$ 194	$ 92
Weighted Average Interest Rate	4.96%	2.02%
Weighted Average Days to Maturity	218 days	126 days
JPM Repo Facility \| Commercial Mortgage Loans \| Collateral Pledged
Repurchase Agreements and Credit Facility [Line Items]
Collateral Pledged	$ 161,829	$ 167,704
Repo Facility \| Commercial Mortgage Loans
Repurchase Agreements and Credit Facility [Line Items]
Committed Financing	600,000	500,000
Amount Outstanding	489,788	307,124
Accrued Interest Payable	$ 784	$ 251
Weighted Average Interest Rate	4.97%	2.11%
Weighted Average Days to Maturity	83 days	242 days
Repo Facility \| Commercial Mortgage Loans \| Collateral Pledged
Repurchase Agreements and Credit Facility [Line Items]
Collateral Pledged	$ 681,014	$ 428,395
Western Alliance Credit Facility \| Commercial Mortgage Loans
Repurchase Agreements and Credit Facility [Line Items]
Committed Financing	$ 75,000	75,000
Amount Outstanding		14,350
Accrued Interest Payable		$ 22
Weighted Average Interest Rate		4.00%
Weighted Average Days to Maturity	161 days	434 days
Western Alliance Credit Facility \| Commercial Mortgage Loans \| Collateral Pledged
Repurchase Agreements and Credit Facility [Line Items]
Collateral Pledged		$ 20,500
Facilities \| Commercial Mortgage Loans
Repurchase Agreements and Credit Facility [Line Items]
Committed Financing	$ 675,000	575,000
Amount Outstanding	489,788	321,474
Accrued Interest Payable	$ 784	$ 273
Weighted Average Interest Rate	4.97%	2.19%
Weighted Average Days to Maturity	83 days	251 days
Facilities \| Commercial Mortgage Loans \| Collateral Pledged
Repurchase Agreements and Credit Facility [Line Items]
Collateral Pledged	$ 681,014	$ 448,895

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Repurchase agreements and credit facility.

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Amount, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity), and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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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.

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