Fair Value of Financial Instruments - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	$ 226,064	$ 221,614
Equity securities	18,414	9,599
Recurring
Fair value of assets and liabilities
Equity securities		9,599
Loans held for sale	159,961	75,807
Fair value hedge, assets	846
Fair value hedge, liabilities	1,988	343
Recurring \| Level I
Fair value of assets and liabilities
Equity securities		6,027
Loans held for sale	0	0
Fair value hedge, assets	0
Fair value hedge, liabilities	0	0
Recurring \| Level II
Fair value of assets and liabilities
Equity securities		3,272
Loans held for sale	159,961	75,807
Fair value hedge, assets	846
Fair value hedge, liabilities	1,988	343
Recurring \| Level III
Fair value of assets and liabilities
Equity securities		300
Loans held for sale	0	0
Fair value hedge, assets	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	53,270	77,430
U. S. Agency securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	53,270	77,430
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	53,270	77,430
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	49,982	50,115
U.S. Sponsored Mortgage-backed securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	49,982	50,115
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	49,982	50,115
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	112,024	83,761
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	76,575	50,639
Municipal securities \| Recurring \| Level III
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	35,449	33,122
Other securities
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	10,788	10,308
Other securities \| Recurring
Fair value of assets and liabilities
Investment securities available-for-sale, at fair value	10,788	10,308
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	10,788	10,308
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	2,315	1,750
Interest rate lock commitment \| Recurring \| Level I
Fair value of assets and liabilities
Derivative asset	0	0
Interest rate lock commitment \| Recurring \| Level II
Fair value of assets and liabilities
Derivative asset	0	0
Interest rate lock commitment \| Recurring \| Level III
Fair value of assets and liabilities
Derivative asset	2,315	1,750
Interest rate swap \| Recurring
Fair value of assets and liabilities
Derivative asset	6,695	1,375
Derivative liability	6,695	1,375
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	6,695	1,375
Derivative liability	6,695	1,375
Interest rate swap \| Recurring \| Level III
Fair value of assets and liabilities
Derivative asset	0	0
Derivative liability	0	0
Interest rate cap \| Recurring
Fair value of assets and liabilities
Derivative asset		8
Interest rate cap \| Recurring \| Level I
Fair value of assets and liabilities
Derivative asset		0
Interest rate cap \| Recurring \| Level II
Fair value of assets and liabilities
Derivative asset		8
Interest rate cap \| Recurring \| Level III
Fair value of assets and liabilities
Derivative asset		0
Mortgage-backed security hedges \| Recurring
Fair value of assets and liabilities
Derivative liability	231	853
Mortgage-backed security hedges \| Recurring \| Level I
Fair value of assets and liabilities
Derivative liability	0	0
Mortgage-backed security hedges \| Recurring \| Level II
Fair value of assets and liabilities
Derivative liability	231	853
Mortgage-backed security hedges \| Recurring \| Level III
Fair value of assets and liabilities
Derivative liability	$ 0	$ 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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