Fair Value Measurements - Summary of Financial Instruments Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Assets
Securities available for sale	$ 451,770	$ 400,146
State tax credits held for sale	5,941	11,689
Portion at Other than Fair Value, Fair Value Disclosure
Assets
State tax credits held for sale	39,900
Total Fair Value
Assets
Securities available for sale	451,770	400,146
State tax credits held for sale	49,588	42,970
Derivative financial instruments	1,155	909
Liabilities
Derivative financial instruments	1,155	907
Obligations of U.S. Government-sponsored enterprises
Assets
Securities available for sale	99,008	91,826
Obligations of states and political subdivisions
Assets
Securities available for sale	41,701	34,881
Residential mortgage-backed securities
Assets
Securities available for sale	311,061	273,439
Recurring basis \| Total Fair Value
Assets
Securities available for sale	451,770	400,146
State tax credits held for sale	5,941	11,689
Derivative financial instruments	1,155	909
Assets, Fair Value Disclosure	458,866	412,744
Liabilities
Derivative financial instruments	1,155	907
Total liabilities	1,155	907
Recurring basis \| Obligations of U.S. Government-sponsored enterprises \| Total Fair Value
Assets
Securities available for sale	99,008	91,826
Recurring basis \| Obligations of states and political subdivisions \| Total Fair Value
Assets
Securities available for sale	41,701	34,881
Recurring basis \| Residential mortgage-backed securities \| Total Fair Value
Assets
Securities available for sale	311,061	273,439
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	448,693	397,087
State tax credits held for sale	0	0
Derivative financial instruments	1,155	909
Assets, Fair Value Disclosure	449,848	397,996
Liabilities
Derivative financial instruments	1,155	907
Total liabilities	1,155	907
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Obligations of U.S. Government-sponsored enterprises
Assets
Securities available for sale	99,008	91,826
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Obligations of states and political subdivisions
Assets
Securities available for sale	38,624	31,822
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Residential mortgage-backed securities
Assets
Securities available for sale	311,061	273,439
Recurring basis \| Significant Unobservable Inputs (Level 3)
Assets
Securities available for sale	3,077	3,059
State tax credits held for sale	5,941	11,689
Derivative financial instruments	0	0
Assets, Fair Value Disclosure	9,018	14,748
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	3,077	3,059
Recurring basis \| Significant Unobservable Inputs (Level 3) \| Residential mortgage-backed securities
Assets
Securities available for sale	0	0
State tax credits held for sale, at fair value \| Recurring basis \| Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	$ 406	$ 558

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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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