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Summary of Significant Accounting Policies (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 USD ($) segment item | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Jan. 18, 2022 $ / shares
Number of banking centres | item | 63 |  |  |
Operating segment | segment | 1 |  |  |
Reportable Segment | segment | 1 |  |  |
Deferred tax assets | $ 23,065,000 | $ 18,972,000 |  |
Retained earnings | $ 252,011,000 | 236,579,000 |  |
Period from due date after which accrual of interest income is discontinued | 90 days |  |  |
Goodwill and Core Deposit Intangible |  |  |  |
Amortization of core deposit intangibles | $ 644,000 | 494,000 | $ 539,000 |
Subsequent Events |  |  |  |
Percentage of forfeiture assumption for group grant | 5.00% |  |  |
Core Deposits |  |  |  |
Goodwill and Core Deposit Intangible |  |  |  |
Carrying value of the intangible asset | $ 16,300,000 |  |  |
Amortization of core deposit intangibles | 644,000 | 494,000 | $ 539,000 |
Expected future annual amortization expense: |  |  |  |
Estimated future amortization expense for the core deposit intangible for the year ending December 31, 2022 | 2,600,000 |  |  |
Estimated future amortization expense for the core deposit intangible for the year ending December 31, 2023 | 2,500,000 |  |  |
Estimated future amortization expense for the core deposit intangible for the year ending December 31, 2024 | 2,300,000 |  |  |
Estimated future amortization expense for the core deposit intangible for the year ending December 31, 2025 | 2,100,000 |  |  |
Estimated future amortization expense for the core deposit intangible for the year ending December 31, 2026 | $ 1,800,000 |  |  |
GCFC/ABC Bank | Core Deposits |  |  |  |
Goodwill and Core Deposit Intangible |  |  |  |
Useful life (in years) | 10 years |  |  |
Remaining intangible asset |  | $ 2,200,000 |  |
West Suburban Bancorp, Inc | Core Deposits |  |  |  |
Goodwill and Core Deposit Intangible |  |  |  |
Intangible asset recorded | $ 14,800,000 |  |  |
Subsequent Event |  |  |  |
Subsequent Events |  |  |  |
Cash dividend declared (per share) | $ / shares |  |  |  | $ 0.05

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