Fair Value of Financial Instruments - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair value of assets and liabilities
Securities available-for-sale	$ 226,504	$ 231,507
Recurring
Fair value of assets and liabilities
Loans held for sale	51,280	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	51,280	66,794
Recurring \| Level III
Fair value of assets and liabilities
Loans held for sale	0	0
Recurring \| Interest rate lock commitment
Fair value of assets and liabilities
Derivative asset	2,312	1,426
Recurring \| Interest rate lock commitment \| Level I
Fair value of assets and liabilities
Derivative asset	0	0
Recurring \| Interest rate lock commitment \| Level II
Fair value of assets and liabilities
Derivative asset	0	0
Recurring \| Interest rate lock commitment \| Level III
Fair value of assets and liabilities
Derivative asset	2,312	1,426
Recurring \| Interest rate swap
Fair value of assets and liabilities
Derivative asset	765	268
Derivative liability	765	268
Recurring \| Interest rate swap \| Level I
Fair value of assets and liabilities
Derivative asset	0	0
Derivative liability	0	0
Recurring \| Interest rate swap \| Level II
Fair value of assets and liabilities
Derivative asset	765	268
Derivative liability	765	268
Recurring \| Interest rate swap \| Level III
Fair value of assets and liabilities
Derivative asset	0	0
Derivative liability	0	0
Recurring \| Interest rate cap
Fair value of assets and liabilities
Derivative asset	103	33
Recurring \| Interest rate cap \| Level I
Fair value of assets and liabilities
Derivative asset	0	0
Recurring \| Interest rate cap \| Level II
Fair value of assets and liabilities
Derivative asset	103	33
Recurring \| Interest rate cap \| Level III
Fair value of assets and liabilities
Derivative asset	0	0
Recurring \| Mortgage-backed security hedges
Fair value of assets and liabilities
Derivative liability	114	78
Recurring \| Mortgage-backed security hedges \| Level I
Fair value of assets and liabilities
Derivative liability	0	0
Recurring \| Mortgage-backed security hedges \| Level II
Fair value of assets and liabilities
Derivative liability	114	78
Recurring \| Mortgage-backed security hedges \| Level III
Fair value of assets and liabilities
Derivative liability	0	0
Recurring \| U.S. Government Agency securities
Fair value of assets and liabilities
Securities available-for-sale	80,795	80,945
Recurring \| U.S. Government Agency securities \| Level I
Fair value of assets and liabilities
Securities available-for-sale	0	0
Recurring \| U.S. Government Agency securities \| Level II
Fair value of assets and liabilities
Securities available-for-sale	80,795	80,945
Recurring \| U.S. Government Agency securities \| Level III
Fair value of assets and liabilities
Securities available-for-sale	0	0
Recurring \| U.S. Sponsored Mortgage-backed securities
Fair value of assets and liabilities
Securities available-for-sale	56,318	58,154
Recurring \| U.S. Sponsored Mortgage-backed securities \| Level I
Fair value of assets and liabilities
Securities available-for-sale	0	0
Recurring \| U.S. Sponsored Mortgage-backed securities \| Level II
Fair value of assets and liabilities
Securities available-for-sale	56,318	58,154
Recurring \| U.S. Sponsored Mortgage-backed securities \| Level III
Fair value of assets and liabilities
Securities available-for-sale	0	0
Recurring \| Municipal securities
Fair value of assets and liabilities
Securities available-for-sale	80,105	75,842
Recurring \| Municipal securities \| Level I
Fair value of assets and liabilities
Securities available-for-sale	0	0
Recurring \| Municipal securities \| Level II
Fair value of assets and liabilities
Securities available-for-sale	57,534	52,933
Recurring \| Municipal securities \| Level III
Fair value of assets and liabilities
Securities available-for-sale	22,571	22,909
Recurring \| Other securities
Fair value of assets and liabilities
Securities available-for-sale	9,286
Recurring \| Other securities \| Level I
Fair value of assets and liabilities
Securities available-for-sale	0
Recurring \| Other securities \| Level II
Fair value of assets and liabilities
Securities available-for-sale	9,286
Recurring \| Other securities \| Level III
Fair value of assets and liabilities
Securities available-for-sale	0
Recurring \| Equity securities
Fair value of assets and liabilities
Securities available-for-sale	6,979	16,566
Recurring \| Equity securities \| Level I
Fair value of assets and liabilities
Securities available-for-sale	6,079	1,607
Recurring \| Equity securities \| Level II
Fair value of assets and liabilities
Securities available-for-sale	0	14,959
Recurring \| Equity securities \| Level III
Fair value of assets and liabilities
Securities available-for-sale	$ 900	$ 0

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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