Fair Value Measurements (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
ASSETS
Trading	$ 1,601	$ 1,324
Trading Securities, Equity	20,075	0
Available for sale	445,750	447,498
Loans held for sale (at fair value)	3,937	4,768
Derivative Asset, Fair Value, Gross Asset	20,870	17,318
Recurring fair value measurements
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS	473,512	455,373
Recurring fair value measurements \| Trading Securities [Member]
ASSETS
Trading	1,601	1,324
Recurring fair value measurements \| U.S. Government agency securities
ASSETS
Available for sale	34,943	35,430
Recurring fair value measurements \| Agency mortgage-backed securities
ASSETS
Available for sale	223,211	215,764
Recurring fair value measurements \| Agency collateralized mortgage obligations
ASSETS
Available for sale	135,192	122,012
Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Available for sale	2,254	2,274
Recurring fair value measurements \| Single issuer trust preferred securities issued by banks and insurers
ASSETS
Available for sale	2,005	2,016
Recurring fair value measurements \| Pooled trust preferred securities issued by banks and insurers
ASSETS
Available for sale	1,655	1,640
Recurring fair value measurements \| Small Business Administration Pooled Securities [Member]
ASSETS
Available for sale	46,490	47,778
Recurring fair value measurements \| Equity securities
ASSETS
Trading Securities, Equity	20,075
Available for sale		20,584
Recurring fair value measurements \| Loans held for sale
ASSETS
Loans held for sale (at fair value)	3,937	4,768
Recurring fair value measurements \| Derivative Financial Instruments, Assets [Member]
ASSETS
Derivative Asset, Fair Value, Gross Asset	21,040	17,476
Recurring fair value measurements \| Derivative instruments
LIABILITIES
Liabilities, Fair Value Disclosure, Recurring	18,891	15,693
Nonrecurring fair value measurements
LIABILITIES
TOTAL NONRECURRING FAIR VALUE MEASUREMENTS	32,471	34,179
Nonrecurring fair value measurements \| Collateral dependent impaired loans
ASSETS
Assets, Fair Value Disclosure, Nonrecurring	32,113	33,567
Nonrecurring fair value measurements \| Other real estate owned and other foreclosed assets
ASSETS
Assets, Fair Value Disclosure, Nonrecurring	358	612
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS	21,676	21,908
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements \| Trading Securities [Member]
ASSETS
Trading	1,601	1,324
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Available for sale		0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements \| Small Business Administration Pooled Securities [Member]
ASSETS
Available for sale	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements \| Equity securities
ASSETS
Trading Securities, Equity	20,075
Available for sale		20,584
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Nonrecurring fair value measurements
LIABILITIES
TOTAL NONRECURRING FAIR VALUE MEASUREMENTS	0	0
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS	450,181	431,825
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| U.S. Government agency securities
ASSETS
Available for sale	34,943	35,430
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Agency mortgage-backed securities
ASSETS
Available for sale	223,211	215,764
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Agency collateralized mortgage obligations
ASSETS
Available for sale	135,192	122,012
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Available for sale	2,254	2,274
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Single issuer trust preferred securities issued by banks and insurers
ASSETS
Available for sale	2,005	2,016
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Small Business Administration Pooled Securities [Member]
ASSETS
Available for sale	46,490	47,778
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Equity securities
ASSETS
Trading Securities, Equity	0
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Loans held for sale
ASSETS
Available for sale	3,937	4,768
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Derivative Financial Instruments, Assets [Member]
ASSETS
Derivative Asset, Fair Value, Gross Asset	21,040	17,476
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Derivative instruments
LIABILITIES
Liabilities, Fair Value Disclosure, Recurring	18,891	15,693
Significant Other Observable Inputs (Level 2) \| Nonrecurring fair value measurements
LIABILITIES
TOTAL NONRECURRING FAIR VALUE MEASUREMENTS	0	0
Significant Unobservable Inputs (Level 3) \| Recurring fair value measurements
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS	1,655	1,640
Significant Unobservable Inputs (Level 3) \| Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Available for sale		0
Significant Unobservable Inputs (Level 3) \| Recurring fair value measurements \| Pooled trust preferred securities issued by banks and insurers
ASSETS
Available for sale	1,655	1,640
Significant Unobservable Inputs (Level 3) \| Recurring fair value measurements \| Small Business Administration Pooled Securities [Member]
ASSETS
Available for sale	0	0
Significant Unobservable Inputs (Level 3) \| Recurring fair value measurements \| Equity securities
ASSETS
Trading Securities, Equity	0
Significant Unobservable Inputs (Level 3) \| Nonrecurring fair value measurements
LIABILITIES
TOTAL NONRECURRING FAIR VALUE MEASUREMENTS	32,471	34,179
Significant Unobservable Inputs (Level 3) \| Nonrecurring fair value measurements \| Collateral dependent impaired loans
ASSETS
Assets, Fair Value Disclosure, Nonrecurring	32,113	33,567
Significant Unobservable Inputs (Level 3) \| Nonrecurring fair value measurements \| Other real estate owned and other foreclosed assets
ASSETS
Assets, Fair Value Disclosure, Nonrecurring	$ 358	$ 612

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