Fair Value Measurements - Summary of Financial Instruments Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Assets
Securities available for sale	$ 460,797	$ 451,770
State tax credits held for sale	3,585	5,941
Portion at Other than Fair Value, Fair Value Disclosure
Assets
State tax credits held for sale	34,500
Total Fair Value
Assets
Securities available for sale	460,797	451,770
State tax credits held for sale	41,264	49,588
Derivative financial instruments	4,016	1,155
Liabilities
Derivative financial instruments	4,016	1,155
Obligations of U.S. Government-sponsored enterprises
Assets
Securities available for sale	107,660	99,008
Obligations of states and political subdivisions
Assets
Securities available for sale	36,631	41,701
Residential mortgage-backed securities
Assets
Securities available for sale	316,506	311,061
Recurring basis \| Total Fair Value
Assets
Securities available for sale	460,797	451,770
State tax credits held for sale	3,585	5,941
Derivative financial instruments	4,016	1,155
Assets, Fair Value Disclosure	468,398	458,866
Liabilities
Derivative financial instruments	4,016	1,155
Total liabilities	4,016	1,155
Recurring basis \| Obligations of U.S. Government-sponsored enterprises \| Total Fair Value
Assets
Securities available for sale	107,660	99,008
Recurring basis \| Obligations of states and political subdivisions \| Total Fair Value
Assets
Securities available for sale	36,631	41,701
Recurring basis \| Residential mortgage-backed securities \| Total Fair Value
Assets
Securities available for sale	316,506	311,061
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Securities available for sale	0	0
State tax credits held for sale	0	0
Derivative financial instruments	0	0
Assets, Fair Value Disclosure	0	0
Liabilities
Derivative financial instruments	0	0
Total liabilities	0	0
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Obligations of U.S. Government-sponsored enterprises
Assets
Securities available for sale	0	0
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Obligations of states and political subdivisions
Assets
Securities available for sale	0	0
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Residential mortgage-backed securities
Assets
Securities available for sale	0	0
Recurring basis \| Significant Other Observable Inputs (Level 2)
Assets
Securities available for sale	457,708	448,693
State tax credits held for sale	0	0
Derivative financial instruments	4,016	1,155
Assets, Fair Value Disclosure	461,724	449,848
Liabilities
Derivative financial instruments	4,016	1,155
Total liabilities	4,016	1,155
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Obligations of U.S. Government-sponsored enterprises
Assets
Securities available for sale	107,660	99,008
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Obligations of states and political subdivisions
Assets
Securities available for sale	33,542	38,624
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Residential mortgage-backed securities
Assets
Securities available for sale	316,506	311,061
Recurring basis \| Significant Unobservable Inputs (Level 3)
Assets
Securities available for sale	3,089	3,077
State tax credits held for sale	3,585	5,941
Derivative financial instruments	0	0
Assets, Fair Value Disclosure	6,674	9,018
Liabilities
Derivative financial instruments	0	0
Total liabilities	0	0
Recurring basis \| Significant Unobservable Inputs (Level 3) \| Obligations of U.S. Government-sponsored enterprises
Assets
Securities available for sale	0	0
Recurring basis \| Significant Unobservable Inputs (Level 3) \| Obligations of states and political subdivisions
Assets
Securities available for sale	3,089	3,077
Recurring basis \| Significant Unobservable Inputs (Level 3) \| Residential mortgage-backed securities
Assets
Securities available for sale	$ 0	$ 0

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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