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Commitments and Contingencies and Related-Party Transactions (Narrative) (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($) entity
Commitments and Contingencies Disclosure [Abstract]
Financial guarantees in connection with standby letters of credit		$ 0	$ 0
Standby letters of credit expiring within one year		183,300
Standby letters of credit expiring thereafter		33,100
Standby Letters Of Credit, Fees		2,900	$ 2,500
Loss Contingency Accrual		2,200
Concentration Risk [Line Items]
Related Party Transaction, Amounts of Transaction		0
iCap Entities [Member]
Concentration Risk [Line Items]
Number of Defendant Entities | entity			34
Loss Contingency, Damages Sought, Value		290,000
Minimum | Professional Financial Investors, Inc. and Professional Investors Security Fund, Inc. [Member]
Concentration Risk [Line Items]
Loss Contingency, Damages Sought, Value		297,400
Maximum | Professional Financial Investors, Inc. and Professional Investors Security Fund, Inc. [Member]
Concentration Risk [Line Items]
Loss Contingency, Damages Sought, Value		$ 368,100
Product Concentration Risk | Revenue Benchmark | Real Estate Loans As Part Of Loan Portfolio
Concentration Risk [Line Items]
Concentration risk (as a percent)	75.00%	75.00%
Product Concentration Risk | Revenue Benchmark | Multifamily Loans as Part of Loan portfolio [Member]
Concentration Risk [Line Items]
Concentration risk (as a percent)	19.00%	19.00%
Product Concentration Risk | Revenue Benchmark | Commercial Office Loans as Part of Loan portfolio [Member]
Concentration Risk [Line Items]
Concentration risk (as a percent)	8.00%	8.00%

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