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Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk - Commitments (Details) - USD ($) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2023 | Jun. 30, 2023 | Dec. 31, 2022
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | $ 32,577,000 | $ 32,577,000 | $ 36,096,000
Allowance for credit loss on unfunded commitments | 2,700,000 | 2,700,000 |
Allowance for credit loss unfunded commitment, purchase accounting adjustment | 372,000 | 372,000 |
Decrease In allowance for credit loss on unfunded commitments | 650,000 |  |
Commercial unfunded commitments assumptions for decrease in the allowance for credit losses |  | 427,000 |
Accretion of interest income for decrease in the allowance for credit losses |  | 223,000 |
Fixed [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 3,629,000 | 3,629,000 | 6,675,000
Variable [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 28,948,000 | 28,948,000 | 29,421,000
Commitments to Extend Credit to Borrowers [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 32,510,000 | 32,510,000 | 36,029,000
Commitments to Extend Credit to Borrowers [Member] | Fixed [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 3,629,000 | 3,629,000 | 6,675,000
Commitments to Extend Credit to Borrowers [Member] | Variable [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 28,881,000 | 28,881,000 | 29,354,000
Commitments to Extend Credit to Borrowers [Member] | Financial Standby Letter of Credit [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 18,486,000 | 18,486,000 | 18,879,000
Commitments to Extend Credit to Borrowers [Member] | Financial Standby Letter of Credit [Member] | Fixed [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 2,116,000 | 2,116,000 | 3,514,000
Commitments to Extend Credit to Borrowers [Member] | Financial Standby Letter of Credit [Member] | Variable [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 16,370,000 | 16,370,000 | 15,365,000
Commitments to Extend Credit to Borrowers [Member] | Performance Guarantee [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 14,024,000 | 14,024,000 | 17,150,000
Commitments to Extend Credit to Borrowers [Member] | Performance Guarantee [Member] | Fixed [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 1,513,000 | 1,513,000 | 3,161,000
Commitments to Extend Credit to Borrowers [Member] | Performance Guarantee [Member] | Variable [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 12,511,000 | 12,511,000 | 13,989,000
Commitments to Extend Credit Nonborrowers [Member] | Performance Guarantee [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 67,000 | 67,000 | 67,000
Commitments to Extend Credit Nonborrowers [Member] | Performance Guarantee [Member] | Variable [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 67,000 | 67,000 | 67,000
Unused lines of Credit [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Loan commitments | 905,347,000 | 905,347,000 | 999,325,000
Unused lines of Credit [Member] | Fixed [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Loan commitments | 139,654,000 | 139,654,000 | 139,070,000
Unused lines of Credit [Member] | Variable [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Loan commitments | $ 765,693,000 | $ 765,693,000 | $ 860,255,000

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