Fair Value of Financial Instruments - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	$ 297,964	$ 235,821
Equity securities	24,164	18,514
Bank owned life insurance	36,037	35,374
Recurring
Fair value of assets and liabilities
Equity securities	144
Loans held for sale	2,271	109,788
Fair value hedge, assets	2,272	1,770
Bank owned life insurance	36,037	35,374
Fair value hedge, liabilities	2,441	1,418
Recurring \| Level I
Fair value of assets and liabilities
Equity securities	144
Loans held for sale	0	0
Fair value hedge, assets	0	0
Bank owned life insurance	0	0
Fair value hedge, liabilities	0	0
Recurring \| Level II
Fair value of assets and liabilities
Equity securities	0
Loans held for sale	2,271	109,788
Fair value hedge, assets	2,272	1,770
Bank owned life insurance	36,037	35,374
Fair value hedge, liabilities	2,441	1,418
Recurring \| Level III
Fair value of assets and liabilities
Equity securities	0
Loans held for sale	0	0
Fair value hedge, assets	0	0
Bank owned life insurance	0	0
Fair value hedge, liabilities	0	0
U.S. agency securities
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	53,382	51,996
U.S. agency securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	53,382	51,996
U.S. agency securities \| Recurring \| Level I
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	0	0
U.S. agency securities \| Recurring \| Level II
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	53,382	51,996
U.S. agency securities \| Recurring \| Level III
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	0	0
U.S. sponsored mortgage-backed securities
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	68,097	58,312
U.S. sponsored mortgage-backed securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	68,097	58,312
U.S. sponsored mortgage-backed securities \| Recurring \| Level I
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	0	0
U.S. sponsored mortgage-backed securities \| Recurring \| Level II
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	68,097	58,312
U.S. sponsored mortgage-backed securities \| Recurring \| Level III
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	0	0
Municipal securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	153,344	113,092
Municipal securities \| Recurring \| Level I
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	0	0
Municipal securities \| Recurring \| Level II
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	111,236	75,833
Municipal securities \| Recurring \| Level III
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	42,108	37,259
Other debt securities
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	7,500
Other debt securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	7,500
Other debt securities \| Recurring \| Level I
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	0
Other debt securities \| Recurring \| Level II
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	0
Other debt securities \| Recurring \| Level III
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	7,500
Other securities
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	15,641	12,421
Other securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	15,641	12,421
Other securities \| Recurring \| Level I
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	0	0
Other securities \| Recurring \| Level II
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	15,641	12,421
Other securities \| Recurring \| Level III
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	0	0
Interest rate lock commitment \| Recurring
Fair value of assets and liabilities
Derivative asset		1,660
Interest rate lock commitment \| Recurring \| Level I
Fair value of assets and liabilities
Derivative asset		0
Interest rate lock commitment \| Recurring \| Level II
Fair value of assets and liabilities
Derivative asset		0
Interest rate lock commitment \| Recurring \| Level III
Fair value of assets and liabilities
Derivative asset		1,660
Interest rate swap \| Recurring
Fair value of assets and liabilities
Derivative asset	15,735	5,722
Derivative liability	15,735	5,722
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	15,735	5,722
Derivative liability	15,735	5,722
Interest rate swap \| Recurring \| Level III
Fair value of assets and liabilities
Derivative asset	0	0
Derivative liability	$ 0	0
Mortgage-backed security hedges \| Recurring
Fair value of assets and liabilities
Derivative liability		186
Mortgage-backed security hedges \| Recurring \| Level I
Fair value of assets and liabilities
Derivative liability		0
Mortgage-backed security hedges \| Recurring \| Level II
Fair value of assets and liabilities
Derivative liability		186
Mortgage-backed security hedges \| Recurring \| Level III
Fair value of assets and liabilities
Derivative liability		$ 0

Amount 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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The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

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No definition available.

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Fair value of all derivative assets designated as fair value hedging instruments.

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Fair value of all derivative liabilities designated as fair value hedging instruments.

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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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