Fair Value Measurements (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
ASSETS
Debt Securities, Trading	$ 1,800	$ 1,500
Equity Securities, FV-NI	20,357	19,477
Debt Securities, Available-for-sale	437,689	442,752
Derivative Asset, Fair Value, Gross Asset	32,936	26,113
U.S. Government agency securities
ASSETS
Debt Securities, Available-for-sale	32,455	32,038
Agency mortgage-backed securities
ASSETS
Debt Securities, Available-for-sale	217,795	220,105
Pooled trust preferred securities issued by banks and insurers
ASSETS
Debt Securities, Available-for-sale	1,314	1,329
Small Business Administration Pooled Securities [Member]
ASSETS
Debt Securities, Available-for-sale	52,134	51,927
Recurring fair value measurements
ASSETS
Debt Securities, Trading	1,837	1,504
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS	478,899	478,951
Recurring fair value measurements \| Equity Securities [Member]
ASSETS
Equity Securities, FV-NI	20,357	19,477
Recurring fair value measurements \| U.S. Government agency securities
ASSETS
Debt Securities, Available-for-sale	32,455	32,038
Recurring fair value measurements \| Agency mortgage-backed securities
ASSETS
Debt Securities, Available-for-sale	217,795	220,105
Recurring fair value measurements \| Agency collateralized mortgage obligations
ASSETS
Debt Securities, Available-for-sale	131,531	134,911
Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Debt Securities, Available-for-sale	1,739	1,735
Recurring fair value measurements \| Single issuer trust preferred securities issued by banks and insurers
ASSETS
Debt Securities, Available-for-sale	721	707
Recurring fair value measurements \| Pooled trust preferred securities issued by banks and insurers
ASSETS
Debt Securities, Available-for-sale	1,314	1,329
Recurring fair value measurements \| Small Business Administration Pooled Securities [Member]
ASSETS
Debt Securities, Available-for-sale	52,134	51,927
Recurring fair value measurements \| Loans held for sale
ASSETS
Loans Held-for-sale, Fair Value Disclosure	5,586	6,431
Recurring fair value measurements \| Derivative Financial Instruments, Assets [Member]
ASSETS
Derivative Asset, Fair Value, Gross Asset	33,192	26,310
Recurring fair value measurements \| Derivative instruments
LIABILITIES
Financial and Nonfinancial Liabilities, Fair Value Disclosure	19,762	17,523
Nonrecurring fair value measurements
LIABILITIES
TOTAL NONRECURRING FAIR VALUE MEASUREMENTS	28,261	29,109
Nonrecurring fair value measurements \| Collateral dependent impaired loans
ASSETS
Assets, Fair Value Disclosure	28,261	29,109
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements
ASSETS
Debt Securities, Trading	1,837	1,504
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS	22,194	20,981
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements \| Equity Securities [Member]
ASSETS
Equity Securities, FV-NI	20,357	19,477
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Debt Securities, 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
Debt Securities, Available-for-sale	0	0
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	455,391	456,641
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Equity Securities [Member]
ASSETS
Equity Securities, FV-NI	0	0
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| U.S. Government agency securities
ASSETS
Debt Securities, Available-for-sale	32,455	32,038
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Agency mortgage-backed securities
ASSETS
Debt Securities, Available-for-sale	217,795	220,105
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Agency collateralized mortgage obligations
ASSETS
Debt Securities, Available-for-sale	131,531	134,911
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Debt Securities, Available-for-sale	1,739	1,735
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Single issuer trust preferred securities issued by banks and insurers
ASSETS
Debt Securities, Available-for-sale	721	707
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Small Business Administration Pooled Securities [Member]
ASSETS
Debt Securities, Available-for-sale	52,134	51,927
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Loans held for sale
ASSETS
Loans Held-for-sale, Fair Value Disclosure	5,586	6,431
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Derivative Financial Instruments, Assets [Member]
ASSETS
Derivative Asset, Fair Value, Gross Asset	33,192	26,310
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Derivative instruments
LIABILITIES
Financial and Nonfinancial Liabilities, Fair Value Disclosure	19,762	17,523
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	1,314	1,329
Significant Unobservable Inputs (Level 3) \| Recurring fair value measurements \| Equity Securities [Member]
ASSETS
Equity Securities, FV-NI	0	0
Significant Unobservable Inputs (Level 3) \| Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Debt Securities, Available-for-sale		0
Significant Unobservable Inputs (Level 3) \| Recurring fair value measurements \| Pooled trust preferred securities issued by banks and insurers
ASSETS
Debt Securities, Available-for-sale	1,314	1,329
Significant Unobservable Inputs (Level 3) \| Recurring fair value measurements \| Small Business Administration Pooled Securities [Member]
ASSETS
Debt Securities, Available-for-sale	0	0
Significant Unobservable Inputs (Level 3) \| Nonrecurring fair value measurements
LIABILITIES
TOTAL NONRECURRING FAIR VALUE MEASUREMENTS	28,261	29,109
Significant Unobservable Inputs (Level 3) \| Nonrecurring fair value measurements \| Collateral dependent impaired loans
ASSETS
Assets, Fair Value Disclosure	$ 28,261	$ 29,109

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