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Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Jan. 01, 2019 | Dec. 31, 2018
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |
Allowance for estimated losses on commitments | $ 38,973 | $ 37,607 | $ 28,707 |  | $ 27,497
Unfounded credit commitment | 1,852 | 808 |  |  |
Operating lease right-of-use assets | 33,943 | 36,741 |  | $ 43,600 |
Operating lease liabilities | 39,851 | 42,734 |  | $ 47,300 |
Accrued interest receivable associated with debt securities available-for-sale | 2,500 |  |  |  |
Ending balance: individually evaluated for impairment | 9,986 | 13,242 |  |  |
Financing receivable, accrued interest receivable | $ 9,400 |  |  |  |
Threshold of membership investment component, percentage | 0.125% |  |  |  |
Threshold of membership investment component | $ 1 |  |  |  |
Activity based investment component as a percentage of outstanding advances | 4.50% |  |  |  |
Goodwill | $ 41,012 | $ 41,320 |  |  |
ESOP repayment period (years) | 30 years |  |  |  |
Effect of non-vested restricted stock and stock options outstanding (in shares) | 337,768 | 64,459 | 380,362 |  |
Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |
Increase in allowance for credit losses |  | $ 11,100 |  |  |
Allowance for estimated losses on commitments | $ 10,400 | 10,353 | $ 0 |  | $ 0
Unfounded credit commitment |  | 737 |  |  |
PCD loan related reserves | $ 6,800 | 6,800 |  |  |
Non-PCD loan related reserves |  | $ 4,300 |  |  |
COVID-19 |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |
Loan modification program, payment deferral period | 90 days |  |  |  |
Loan modification program, extension for payment deferral period | 90 days |  |  |  |
Loan modification program, maximum deferral period | 180 days |  |  |  |
Minimum |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |
Ending balance: individually evaluated for impairment | $ 500 |  |  |  |
Building |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |
Estimated useful lives of significant classes of assets (years) | 40 years |  |  |  |
Furniture And Equipment | Minimum |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |
Estimated useful lives of significant classes of assets (years) | 5 years |  |  |  |
Furniture And Equipment | Maximum |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |
Estimated useful lives of significant classes of assets (years) | 7 years |  |  |  |
Software |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |
Estimated useful lives of significant classes of assets (years) | 3 years |  |  |  |

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