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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, 2022 | Jun. 30, 2022 | Dec. 31, 2021
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | $ 35,414,000 | $ 35,414,000 | $ 33,288,000
Allowance for Credit Loss on Unfunded Commitments | 3,400,000 | 3,400,000 |
Allowance for Credit Loss Unfunded Commitment, Purchase Accounting Adjustment | 1,300,000 | 1,300,000 |
Decrease In Allowance for Credit Loss on unfunded Commitments | 1,000,000.0 |  |
Commercial unfunded commitments assumptions for decrease in the allowance for credit losses |  | 780,000 |
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 | 13,589,000 | 13,589,000 | 840,000
Variable [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 21,825,000 | 21,825,000 | 32,448,000
Commitments to Extend Credit to Borrowers [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 35,347,000 | 35,347,000 | 33,221,000
Commitments to Extend Credit to Borrowers [Member] | Fixed [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 13,589,000 | 13,589,000 | 840,000
Commitments to Extend Credit to Borrowers [Member] | Variable [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 21,758,000 | 21,758,000 | 32,381,000
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 | 19,649,000 | 19,649,000 | 17,858,000
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 | 5,504,000 | 5,504,000 | 384,000
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 | 14,145,000 | 14,145,000 | 17,474,000
Commitments to Extend Credit to Borrowers [Member] | Performance Guarantee [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Total letters of credit | 15,698,000 | 15,698,000 | 15,363,000
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 | 8,085,000 | 8,085,000 | 456,000
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 | 7,613,000 | 7,613,000 | 14,907,000
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
Letter of Credit [Member] | Unused lines of Credit [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Loan commitments | 850,298,000 | 850,298,000 | 979,890,000
Letter of Credit [Member] | Unused lines of Credit [Member] | Fixed [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Loan commitments | 148,591,000 | 148,591,000 | 84,225,000
Letter of Credit [Member] | Unused lines of Credit [Member] | Variable [Member] |  |  |
Company's contractual commitments due to letters of credit |  |  |
Loan commitments | $ 701,707,000 | $ 701,707,000 | $ 895,665,000

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