Fair Value Measurements (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Investment securities	$ 722,674	$ 589,268
Loans held for sale	18,728	25,096
Other equity investments	218	218
Assets measured at a fair value on a recurring basis	747,909	616,663
Liabilities measured at a fair value on a recurring basis	28	10
Interest Rate Swap [Member]
Derivative asset	6,461	2,201
Interest Rate Swap [Member] \| Derivative Financial Instruments, Assets [Member]
Derivative asset	6,427	2,256
US Agency Securities [Member]
Investment securities	230,325	195,984
Residential Mortgage Backed Securities [Member]
Investment securities	436,349	317,836
Loans held for sale	18,728	25,096
Municipal Bonds [Member]
Investment securities	47,736	62,057
Corporate Bonds [Member]
Investment securities	8,046	13,173
Mortgage Banking Derivative [Member]
Derivative asset	80	43
Derivative liability	28	10
Fair Value, Inputs, Level 2 [Member]
Investment securities	720,956	587,550
Loans held for sale	18,728	25,096
Assets measured at a fair value on a recurring basis	746,111	614,902
Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]
Derivative asset	6,427	2,256
Fair Value, Inputs, Level 2 [Member] \| US Agency Securities [Member]
Investment securities	230,325	195,984
Fair Value, Inputs, Level 2 [Member] \| Residential Mortgage Backed Securities [Member]
Investment securities	436,349	317,836
Fair Value, Inputs, Level 2 [Member] \| Municipal Bonds [Member]
Investment securities	47,736	62,057
Fair Value, Inputs, Level 2 [Member] \| Corporate Bonds [Member]
Investment securities	6,546	11,673
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	1,798	1,761
Liabilities measured at a fair value on a recurring basis	28	10
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	$ 80	$ 43

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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Aggregation of the liabilities reported on the balance sheet measured at fair value on a recurring basis by the entity.

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