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Summary of Significant Accounting Policies - Additional Information (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 USD ($) Segment | Dec. 31, 2020 USD ($)
Finite Lived Intangible Assets [Line Items] |  |
Maximum maturity period for cash equivalents | 90 days |
Number of investment portfolios | 3 |
Number of securities held as trading securities | 0 | 0
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest | $ 2,000 | $ 3,100
Useful lives of premises and equipment | three to forty years |
Number of reportable segments | Segment | 2 |
Core Deposits [Member] |  |
Finite Lived Intangible Assets [Line Items] |  |
Finite-lived intangible asset, useful life | 7 years |
Minimum [Member] |  |
Finite Lived Intangible Assets [Line Items] |  |
Loans Modified in a Troubled Debt Restructuring, Individually Evaluated for Impairment, Principal Balance, Threshold | $ 500 |
ALC [Member] | Minimum [Member] |  |
Finite Lived Intangible Assets [Line Items] |  |
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest | $ 50 |

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