Loans and Investments - Schedule of Loan Modifications (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	$ 949,830	$ 88,100
UPB of loan modifications made during 2024	$ 949,800
Financing receivable, modified in period, percentage of total investment portfolio	8.27%	14.40%
Financing receivable, specific reserve	$ 5,200	$ 17,000
Deferred interest	3,800
Deferred interest for loans previously modified	9,100
Accumulated deferred interest	74,200
UPB of loan modifications made during 2024		$ 1,760,000
Payment Deferral, With Or Without Term Extensions
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	$ 849,365
Weighted average pay rate	5.18%	6.96%
Deferred rate	2.56%	2.09%
Other
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	$ 100,465
Extended Maturity
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	$ 108,700
Financing receivable modified, weighted average term increase from modification	19 months 18 days	9 months 9 days
Payment Deferral And Pay Rate Increase From Time-To-Time
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	$ 470,300
Specific Reserve
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	25,500
Contractual Interest Rate Reduction, Without Term Extensions
Financing Receivable, Modified [Line Items]
Weighted average interest rate reduction		0.72%
Extended Maturity, 23 Months
Financing Receivable, Modified [Line Items]
Financing receivable modified, weighted average term increase from modification		23 months
Multifamily
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	933,340	$ 1,763,867
Multifamily \| Payment Deferral, With Or Without Term Extensions
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	849,365	1,071,069
Multifamily \| Other
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	83,975	217,850
Multifamily \| Extended Maturity
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty		456,548
Multifamily \| Contractual Interest Rate Reduction, Without Term Extensions
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty		18,400
Multifamily \| Extended Maturity, 23 Months
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty		$ 671,000
Single-Family Rental
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	16,490
Single-Family Rental \| Payment Deferral, With Or Without Term Extensions
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	0
Single-Family Rental \| Other
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	$ 16,490

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