Fair Value of Financial Instruments - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Fair value of assets and liabilities
Securities available-for-sale, at fair value	$ 216,714
Equity securities	9,592
Recurring
Fair value of assets and liabilities
Loans held for sale	63,706	$ 66,794
Recurring \| Level I
Fair value of assets and liabilities
Loans held for sale	0	0
Recurring \| Level II
Fair value of assets and liabilities
Loans held for sale	63,706	66,794
Recurring \| Level III
Fair value of assets and liabilities
Loans held for sale	0	0
U. S. Agency securities
Fair value of assets and liabilities
Securities available-for-sale, at fair value	77,712	80,945
U. S. Agency securities \| Recurring
Fair value of assets and liabilities
Securities available-for-sale, at fair value	77,712	80,945
U. S. Agency securities \| Recurring \| Level I
Fair value of assets and liabilities
Securities available-for-sale, at fair value	0	0
U. S. Agency securities \| Recurring \| Level II
Fair value of assets and liabilities
Securities available-for-sale, at fair value	77,712	80,945
U. S. Agency securities \| Recurring \| Level III
Fair value of assets and liabilities
Securities available-for-sale, at fair value	0	0
U.S. Sponsored Mortgage-backed securities
Fair value of assets and liabilities
Securities available-for-sale, at fair value	50,954	58,154
U.S. Sponsored Mortgage-backed securities \| Recurring
Fair value of assets and liabilities
Securities available-for-sale, at fair value	50,954	58,154
U.S. Sponsored Mortgage-backed securities \| Recurring \| Level I
Fair value of assets and liabilities
Securities available-for-sale, at fair value	0	0
U.S. Sponsored Mortgage-backed securities \| Recurring \| Level II
Fair value of assets and liabilities
Securities available-for-sale, at fair value	50,954	58,154
U.S. Sponsored Mortgage-backed securities \| Recurring \| Level III
Fair value of assets and liabilities
Securities available-for-sale, at fair value	0	0
Municipal securities \| Recurring
Fair value of assets and liabilities
Securities available-for-sale, at fair value	78,951	75,842
Municipal securities \| Recurring \| Level I
Fair value of assets and liabilities
Securities available-for-sale, at fair value	0	0
Municipal securities \| Recurring \| Level II
Fair value of assets and liabilities
Securities available-for-sale, at fair value	49,627	52,933
Municipal securities \| Recurring \| Level III
Fair value of assets and liabilities
Securities available-for-sale, at fair value	29,324	22,909
Other securities
Fair value of assets and liabilities
Securities available-for-sale, at fair value	9,097
Other securities \| Recurring
Fair value of assets and liabilities
Securities available-for-sale, at fair value	9,097
Other securities \| Recurring \| Level I
Fair value of assets and liabilities
Securities available-for-sale, at fair value	0
Other securities \| Recurring \| Level II
Fair value of assets and liabilities
Securities available-for-sale, at fair value	9,097
Other securities \| Recurring \| Level III
Fair value of assets and liabilities
Securities available-for-sale, at fair value	0
Equity securities \| Recurring
Fair value of assets and liabilities
Equity securities	9,592	16,566
Equity securities \| Recurring \| Level I
Fair value of assets and liabilities
Equity securities	6,020	1,607
Equity securities \| Recurring \| Level II
Fair value of assets and liabilities
Equity securities	0	14,059
Equity securities \| Recurring \| Level III
Fair value of assets and liabilities
Equity securities	3,572	900
Interest rate lock commitment \| Recurring
Fair value of assets and liabilities
Derivative asset	1,672	1,426
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	1,672	1,426
Interest rate swap \| Recurring
Fair value of assets and liabilities
Derivative asset	387	268
Derivative liability	387	268
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	387	268
Derivative liability	387	268
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	63	33
Interest rate cap \| Recurring \| Level I
Fair value of assets and liabilities
Derivative asset	0	0
Interest rate cap \| Recurring \| Level II
Fair value of assets and liabilities
Derivative asset	63	33
Interest rate cap \| Recurring \| Level III
Fair value of assets and liabilities
Derivative asset	0	0
Mortgage-backed security hedges \| Recurring
Fair value of assets and liabilities
Derivative asset	470
Derivative liability		78
Mortgage-backed security hedges \| Recurring \| Level I
Fair value of assets and liabilities
Derivative asset	0
Derivative liability		0
Mortgage-backed security hedges \| Recurring \| Level II
Fair value of assets and liabilities
Derivative asset	470
Derivative liability		78
Mortgage-backed security hedges \| Recurring \| Level III
Fair value of assets and liabilities
Derivative asset	$ 0
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).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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