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Loans Receivable, Allowance for Credit Losses and Credit Quality - Consumer loan pools (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Loans Receivable, Allowance for Credit Losses and Credit Quality |  |  |  |  |
Loans receivable, net of deferred fees | $ 4,716,129 |  | $ 4,716,129 |  | $ 4,333,152
Carrying value of loans pledged to secure advances | 41,453 |  | 41,453 |  | 120,835
Investment securities pledged | FHLB |  |  |  |  |
Loans Receivable, Allowance for Credit Losses and Credit Quality |  |  |  |  |
Carrying value of loans pledged to secure advances | 1,230,000 |  | 1,230,000 |  | 1,240,000
Consumer |  |  |  |  |
Loans Receivable, Allowance for Credit Losses and Credit Quality |  |  |  |  |
Loans purchased | 20,300 | $ 13,300 | 34,700 | $ 32,900 |
Gross Loan | 203,761 |  | 203,761 |  | 207,051
Premium (Discount) | (3,801) |  | (3,801) |  | (3,910)
Loans receivable, net of deferred fees | 199,960 |  | 199,960 |  | 203,141
Consumer | Student loans |  |  |  |  |
Loans Receivable, Allowance for Credit Losses and Credit Quality |  |  |  |  |
Gross Loan | 5,733 |  | 5,733 |  | 6,954
Premium (Discount) | 35 |  | 35 |  | 42
Loans receivable, net of deferred fees | 5,768 |  | 5,768 |  | 6,996
Consumer | Boat and RV loans |  |  |  |  |
Loans Receivable, Allowance for Credit Losses and Credit Quality |  |  |  |  |
Gross Loan | 41,517 |  | 41,517 |  | 48,147
Premium (Discount) | 937 |  | 937 |  | 1,136
Loans receivable, net of deferred fees | 42,454 |  | 42,454 |  | 49,283
Consumer | Automobile loans |  |  |  |  |
Loans Receivable, Allowance for Credit Losses and Credit Quality |  |  |  |  |
Gross Loan | 68,307 |  | 68,307 |  | 52,092
Loans receivable, net of deferred fees | 68,307 |  | 68,307 |  | 52,092
Consumer | Solar panel loans |  |  |  |  |
Loans Receivable, Allowance for Credit Losses and Credit Quality |  |  |  |  |
Gross Loan | 50,436 |  | 50,436 |  | 55,400
Premium (Discount) | (4,758) |  | (4,758) |  | (5,073)
Loans receivable, net of deferred fees | 45,678 |  | 45,678 |  | 50,327
Consumer | Home improvement loans |  |  |  |  |
Loans Receivable, Allowance for Credit Losses and Credit Quality |  |  |  |  |
Gross Loan | 37,768 |  | 37,768 |  | 44,458
Premium (Discount) | (15) |  | (15) |  | (15)
Loans receivable, net of deferred fees | $ 37,753 |  | $ 37,753 |  | $ 44,443

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