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Commitments and Contingencies (Narrative) (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract] |  |
Standby letters of credit, required to perform on financial guarantees | $ 0 | $ 0
Standby letters of credit that expire within one year | 198,500,000 |
Standby letters of credit that expire thereafter | 14,000,000 |
Standby letters of credit fees | 2,500,000 | $ 1,900,000
Residential mortgage loan repurchase reserve liability | $ 200,000 |
Days past due of GNMA loans available for repurchase | 90 days |
GNMA Loans past due by 90 days, but not yet repurchased | $ 1,000,000 |
Loss Contingency Accrual | 5,700,000 |
Concentration Risk [Line Items] |  |
Prior Bankruptcy Recoveries by Plaintiffs | 110,000,000 |
Minimum |  |
Concentration Risk [Line Items] |  |
Loss Contingency, Damages Sought, Value | 386,200,000 |
Maximum |  |
Concentration Risk [Line Items] |  |
Loss Contingency, Damages Sought, Value | $ 429,800,000 |
Product Concentration Risk | Revenue Benchmark | Real Estate Loans as Part of Loan portfolio |  |
Concentration Risk [Line Items] |  |
Concentration risk, percentage | 75.00% | 78.00%
Product Concentration Risk | Revenue Benchmark | Multifamily Loans as Part of Loan portfolio [Member] |  |
Concentration Risk [Line Items] |  |
Concentration risk, percentage | 19.00% |
Product Concentration Risk | Revenue Benchmark | Commercial Office Loans as Part of Loan portfolio [Member] |  |
Concentration Risk [Line Items] |  |
Concentration risk, percentage | 8.00% |

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- Definition GNMA loans that have the unilateral right, but not the obligation, to repurchase that are past due 90 days or more and have been recorded as loans as part of the loan portfolio as if they had been repurchased. + References No definition available. + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 954 -SubTopic 310 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481027/954-310-50-2 + Details
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