Loans and Investments - Schedule of Loan Modifications (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty		$ 949,830
Weighted average pay rate after modification	4.27%	4.52%
Deferred rate after modification	2.59%	3.38%
UPB of loan modifications made during the current year	$ 479,300
Financing receivable, modified in period, percentage of total investment portfolio	4.00%	8.00%
Financing receivable, specific reserve	$ 1,000	$ 5,200
Weighted average pay rate before modification	5.32%	6.82%
Total UPB of modified loans that had been previously modified	$ 308,100	$ 370,900
Deferred rate before modification	2.29%	1.09%
UPB of loan modifications made in prior year		$ 949,800
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 after modification	4.62%	5.18%
Deferred rate after modification	2.80%	2.56%
Contractual Interest Rate Reduction, With Or Without Term Extensions
Financing Receivable, Modified [Line Items]
Weighted average pay rate after modification	5.26%
Deferred rate after modification	1.08%
Other
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty		$ 100,465
Extended Maturity, 23.5 Months
Financing Receivable, Modified [Line Items]
Financing receivable modified, weighted average term increase from modification	23 months 15 days
Payment Deferral And Pay Rate Increase From Time-To-Time
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	$ 65,100	$ 470,300
Extended Maturity, 18.7 Months
Financing Receivable, Modified [Line Items]
Financing receivable modified, weighted average term increase from modification	18 months 21 days	19 months 18 days
Specific Reserve
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	$ 33,000	$ 25,500
Multifamily
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	478,800	933,340
Multifamily \| Payment Deferral, With Or Without Term Extensions
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	166,786	849,365
Multifamily \| Contractual Interest Rate Reduction, With Or Without Term Extensions
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	196,594
Multifamily \| Other
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty	$ 115,420	83,975
Multifamily \| Extended Maturity, 18.7 Months
Financing Receivable, Modified [Line Items]
UPB of loan modifications, borrowers experiencing financial difficulty		108,700
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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Financing Receivable, Specific Reserve

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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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Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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