Fair Value Measurements (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
ASSETS
Debt Securities, Trading	$ 2,000	$ 1,500
Equity Securities, FV-NI	21,021	19,477
Debt Securities, Available-for-sale	391,975	442,752
Derivative Asset, Fair Value, Gross Asset	104,450	26,113
U.S. Government agency securities
ASSETS
Debt Securities, Available-for-sale	33,302	32,038
Agency mortgage-backed securities
ASSETS
Debt Securities, Available-for-sale	200,603	220,105
Pooled trust preferred securities issued by banks and insurers
ASSETS
Debt Securities, Available-for-sale	1,106	1,329
Small Business Administration Pooled Securities [Member]
ASSETS
Debt Securities, Available-for-sale	59,970	51,927
Recurring fair value measurements
ASSETS
Debt Securities, Trading	1,963	1,504
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS	502,363	478,951
Recurring fair value measurements \| Equity Securities [Member]
ASSETS
Equity Securities, FV-NI	21,021	19,477
Recurring fair value measurements \| U.S. Government agency securities
ASSETS
Debt Securities, Available-for-sale	33,302	32,038
Recurring fair value measurements \| Agency mortgage-backed securities
ASSETS
Debt Securities, Available-for-sale	200,603	220,105
Recurring fair value measurements \| Agency collateralized mortgage obligations
ASSETS
Debt Securities, Available-for-sale	94,538	134,911
Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Debt Securities, Available-for-sale	1,736	1,735
Recurring fair value measurements \| Single issuer trust preferred securities issued by banks and insurers
ASSETS
Debt Securities, Available-for-sale	720	707
Recurring fair value measurements \| Pooled trust preferred securities issued by banks and insurers
ASSETS
Debt Securities, Available-for-sale	1,106	1,329
Recurring fair value measurements \| Small Business Administration Pooled Securities [Member]
ASSETS
Debt Securities, Available-for-sale	59,970	51,927
Recurring fair value measurements \| Loans held for sale
ASSETS
Loans Held-for-sale, Fair Value Disclosure	55,937	6,431
Recurring fair value measurements \| Derivative Financial Instruments, Assets [Member]
ASSETS
Derivative Asset, Fair Value, Gross Asset	106,601	26,310
Recurring fair value measurements \| Derivative instruments
LIABILITIES
Financial and Nonfinancial Liabilities, Fair Value Disclosure	75,134	17,523
Nonrecurring fair value measurements
LIABILITIES
TOTAL NONRECURRING FAIR VALUE MEASUREMENTS	35,145	29,109
Nonrecurring fair value measurements \| Collateral dependent impaired loans
ASSETS
Assets, Fair Value Disclosure	32,645	29,109
Nonrecurring fair value measurements \| Other Real Estate Owned [Member]
ASSETS
Assets, Fair Value Disclosure	2,500
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements
ASSETS
Debt Securities, Trading	1,963	1,504
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS	22,984	20,981
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements \| Equity Securities [Member]
ASSETS
Equity Securities, FV-NI	21,021	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	478,273	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	33,302	32,038
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Agency mortgage-backed securities
ASSETS
Debt Securities, Available-for-sale	200,603	220,105
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Agency collateralized mortgage obligations
ASSETS
Debt Securities, Available-for-sale	94,538	134,911
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Debt Securities, Available-for-sale	1,736	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	720	707
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Small Business Administration Pooled Securities [Member]
ASSETS
Debt Securities, Available-for-sale	59,970	51,927
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Loans held for sale
ASSETS
Loans Held-for-sale, Fair Value Disclosure	55,937	6,431
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Derivative Financial Instruments, Assets [Member]
ASSETS
Derivative Asset, Fair Value, Gross Asset	106,601	26,310
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Derivative instruments
LIABILITIES
Financial and Nonfinancial Liabilities, Fair Value Disclosure	75,134	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	1,106	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	1,106	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	35,145	29,109
Significant Unobservable Inputs (Level 3) \| Nonrecurring fair value measurements \| Collateral dependent impaired loans
ASSETS
Assets, Fair Value Disclosure	32,645	$ 29,109
Significant Unobservable Inputs (Level 3) \| Nonrecurring fair value measurements \| Other Real Estate Owned [Member]
ASSETS
Assets, Fair Value Disclosure	$ 2,500

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