Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Fair value of assets and liabilities
Investment securities available-for-sale	$ 439,023	$ 410,624
Equity securities	29,809	27,585
Recurring
Fair value of assets and liabilities
Equity securities	729	472
Loans held-for-sale		1,062
Recurring \| Level I
Fair value of assets and liabilities
Equity securities	729	472
Loans held-for-sale		0
Recurring \| Level II
Fair value of assets and liabilities
Equity securities	0	0
Loans held-for-sale		1,062
Recurring \| Level III
Fair value of assets and liabilities
Equity securities	0	0
Loans held-for-sale		0
United States government agency securities
Fair value of assets and liabilities
Investment securities available-for-sale	41,971	53,869
United States government agency securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale	41,971	56,992
United States government agency securities \| Recurring \| Level I
Fair value of assets and liabilities
Investment securities available-for-sale	0	0
United States government agency securities \| Recurring \| Level II
Fair value of assets and liabilities
Investment securities available-for-sale	41,971	56,992
United States government agency securities \| Recurring \| Level III
Fair value of assets and liabilities
Investment securities available-for-sale	0	0
United States sponsored mortgage-backed securities
Fair value of assets and liabilities
Investment securities available-for-sale	85,271	95,769
United States sponsored mortgage-backed securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale	85,271	95,769
United States sponsored mortgage-backed securities \| Recurring \| Level I
Fair value of assets and liabilities
Investment securities available-for-sale	0	0
United States sponsored mortgage-backed securities \| Recurring \| Level II
Fair value of assets and liabilities
Investment securities available-for-sale	85,271	95,769
United States sponsored mortgage-backed securities \| Recurring \| Level III
Fair value of assets and liabilities
Investment securities available-for-sale	0	0
United States treasury securities
Fair value of assets and liabilities
Investment securities available-for-sale	82,422	3,123
United States treasury securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale	82,422
United States treasury securities \| Recurring \| Level I
Fair value of assets and liabilities
Investment securities available-for-sale	82,422
United States treasury securities \| Recurring \| Level II
Fair value of assets and liabilities
Investment securities available-for-sale	0
United States treasury securities \| Recurring \| Level III
Fair value of assets and liabilities
Investment securities available-for-sale	0
Municipal securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale	207,423	231,887
Municipal securities \| Recurring \| Level I
Fair value of assets and liabilities
Investment securities available-for-sale	0	0
Municipal securities \| Recurring \| Level II
Fair value of assets and liabilities
Investment securities available-for-sale	166,009	188,208
Municipal securities \| Recurring \| Level III
Fair value of assets and liabilities
Investment securities available-for-sale	41,414	43,679
Other securities
Fair value of assets and liabilities
Investment securities available-for-sale	14,436	18,476
Other securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale	14,436	18,476
Other securities \| Recurring \| Level I
Fair value of assets and liabilities
Investment securities available-for-sale	0	0
Other securities \| Recurring \| Level II
Fair value of assets and liabilities
Investment securities available-for-sale	14,436	18,476
Other securities \| Recurring \| Level III
Fair value of assets and liabilities
Investment securities available-for-sale	0	0
Interest rate swap \| Recurring
Fair value of assets and liabilities
Derivative asset	8,444	13,822
Derivative liability	8,444	13,822
Interest rate swap \| Recurring \| Level I
Fair value of assets and liabilities
Derivative asset	0	0
Derivative liability	0	0
Interest rate swap \| Recurring \| Level II
Fair value of assets and liabilities
Derivative asset	8,444	13,822
Derivative liability	8,444	13,822
Interest rate swap \| Recurring \| Level III
Fair value of assets and liabilities
Derivative asset	0	0
Derivative liability	0	0
Fair value hedge \| Recurring
Fair value of assets and liabilities
Derivative asset	1,699	2,215
Derivative liability	1,129	2,141
Fair value hedge \| Recurring \| Level I
Fair value of assets and liabilities
Derivative asset	0	0
Derivative liability	0	0
Fair value hedge \| Recurring \| Level II
Fair value of assets and liabilities
Derivative asset	1,699	2,215
Derivative liability	1,129	2,141
Fair value hedge \| Recurring \| Level III
Fair value of assets and liabilities
Derivative asset	0	0
Derivative liability	$ 0	$ 0

Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
-Name Accounting Standards Codification
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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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