Borrowing Arrangements - Credit Lines, Balances Outstanding and Pledged Collateral (Details) - USD ($) |
Dec. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Borrowing Arrangements | ||
| Borrowings | $ 73,000,000 | $ 133,442,000 |
| Unsecured Credit Lines | ||
| Borrowing Arrangements | ||
| Credit limit | 110,000,000 | 110,000,000 |
| Borrowings | 0 | 0 |
| Federal Home Loan Bank Borrowings | ||
| Borrowing Arrangements | ||
| Credit limit | 809,391,000 | 738,556,000 |
| Borrowings | 73,000,000 | 133,442,000 |
| Fair value of collateral | 1,230,691,000 | 1,083,041,000 |
| Federal Home Loan Bank Borrowings | Asset Pledged as Collateral | ||
| Borrowing Arrangements | ||
| Collateral pledged | 1,446,828,000 | 1,236,732,000 |
| Federal Reserve Bank | ||
| Borrowing Arrangements | ||
| Credit limit | 3,411,000 | 3,669,000 |
| Borrowings | 0 | 0 |
| Fair value of collateral | 3,536,000 | 3,828,000 |
| Federal Reserve Bank | Asset Pledged as Collateral | ||
| Borrowing Arrangements | ||
| Collateral pledged | $ 3,910,000 | $ 4,406,000 |