Fair Value Measurements (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Investment securities	$ 589,268	$ 538,108
Loans held for sale	25,096	51,629
Other equity investments	218	218
Assets measured at a fair value on a recurring basis	616,663	589,851
Derivative liability	10	692
Liabilities measured at a fair value on a recurring basis	10	747
Interest Rate Swap [Member]
Derivative asset	2,201
Derivative liability		692
Interest Rate Swap [Member] \| Derivative Financial Instruments, Assets [Member]
Derivative asset	2,256
US Agency Securities [Member]
Investment securities	195,984	106,142
Residential Mortgage Backed Securities [Member]
Investment securities	317,836	326,239
Loans held for sale	25,096	51,629
Municipal Bonds [Member]
Investment securities	62,057	95,930
Corporate Bonds [Member]
Investment securities	13,173	9,579
Mortgage Banking Derivative [Member]
Derivative asset	43	114
Derivative liability		55
Fair Value, Inputs, Level 2 [Member]
Investment securities	587,550
Loans held for sale	25,096	51,629
Assets measured at a fair value on a recurring basis	614,902	588,019
Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]
Derivative asset	2,256
Derivative liability		692
Liabilities measured at a fair value on a recurring basis		692
Fair Value, Inputs, Level 2 [Member] \| US Agency Securities [Member]
Investment securities	195,984	106,142
Fair Value, Inputs, Level 2 [Member] \| Residential Mortgage Backed Securities [Member]
Investment securities	317,836	326,239
Loans held for sale		51,629
Fair Value, Inputs, Level 2 [Member] \| Municipal Bonds [Member]
Investment securities	62,057	95,930
Fair Value, Inputs, Level 2 [Member] \| Corporate Bonds [Member]
Investment securities	11,673	8,079
Fair Value, Inputs, Level 3 [Member]
Investment securities	1,718
Other equity investments	218	218
Assets measured at a fair value on a recurring basis	1,761	1,832
Derivative liability	10
Liabilities measured at a fair value on a recurring basis	10	55
Fair Value, Inputs, Level 3 [Member] \| Corporate Bonds [Member]
Investment securities	1,500	1,500
Fair Value, Inputs, Level 3 [Member] \| Mortgage Banking Derivative [Member]
Derivative asset	$ 43	114
Derivative liability		$ 55

Fair value portion of other equity investments.

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

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