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Summary of Significant Accounting Policies (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 USD ($) item segment | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Jan. 19, 2021 $ / shares
Number of banking centres | item | 29 |  |  |
Operating segment | segment | 1 |  |  |
Reportable Segment | segment | 1 |  |  |
90-Days or Greater Past Due Loans |  |  |  |
Period from due date after which accrual of interest income is discontinued | 90 days |  |  |
Goodwill and Core Deposit Intangible |  |  |  |
Percentage of increase in share price | 28.80% |  |  |
Amortization of core deposit intangible | $ 494,000 | $ 539,000 | $ 387,000 |
Residential Owner Occupied Loan [Member] |  |  |  |
Allowance for Credit Losses ("ACL") |  |  |  |
Remaining life | 6 years |  |  |
Residential Investor Loan [Member] |  |  |  |
Allowance for Credit Losses ("ACL") |  |  |  |
Remaining life | 4 years 6 months |  |  |
Core Deposits [Member] |  |  |  |
Goodwill and Core Deposit Intangible |  |  |  |
Amortization of core deposit intangible | $ 494,000 | $ 539,000 | $ 387,000 |
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] |  |  |  |
Estimated future amortization expense for the core deposit intangible for the year ending December 31, 2021 | 459,000 |  |  |
Estimated future amortization expense for the core deposit intangible for the year ending December 31, 2022 | 421,000 |  |  |
Estimated future amortization expense for the core deposit intangible for the year ending December 31, 2023 | 379,000 |  |  |
Estimated future amortization expense for the core deposit intangible for the year ending December 31, 2024 | 331,000 |  |  |
Estimated future amortization expense for the core deposit intangible for the year ending December 31, 2025 | $ 274,000 |  |  |
GCFC/ABC Bank | Core Deposits [Member] |  |  |  |
Goodwill and Core Deposit Intangible |  |  |  |
Useful life (in years) | 10 years |  |  |
Remaining intangible asset | $ 2,200,000 |  |  |
Subsequent Event |  |  |  |
Subsequent Events |  |  |  |
Dividends Payable, Amount Per Share | $ / shares |  |  |  | $ 0.01

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