Fair Value Measurements (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
ASSETS
Debt Securities, Trading	$ 1,900	$ 1,500
Equity Securities, FV-NI	20,807	19,477
Debt Securities, Available-for-sale	393,148	442,752
Derivative Asset, Fair Value, Gross Asset	78,176	26,113
U.S. Government agency securities
ASSETS
Debt Securities, Available-for-sale	32,923	32,038
Agency mortgage-backed securities
ASSETS
Debt Securities, Available-for-sale	197,665	220,105
Pooled trust preferred securities issued by banks and insurers
ASSETS
Debt Securities, Available-for-sale	1,281	1,329
Small Business Administration Pooled Securities [Member]
ASSETS
Debt Securities, Available-for-sale	60,181	51,927
Recurring fair value measurements
ASSETS
Debt Securities, Trading	1,939	1,504
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS	566,328	478,951
Recurring fair value measurements \| Equity Securities [Member]
ASSETS
Equity Securities, FV-NI	20,807	19,477
Recurring fair value measurements \| U.S. Government agency securities
ASSETS
Debt Securities, Available-for-sale	32,923	32,038
Recurring fair value measurements \| Agency mortgage-backed securities
ASSETS
Debt Securities, Available-for-sale	197,665	220,105
Recurring fair value measurements \| Agency collateralized mortgage obligations
ASSETS
Debt Securities, Available-for-sale	98,643	134,911
Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Debt Securities, Available-for-sale	1,738	1,735
Recurring fair value measurements \| Single issuer trust preferred securities issued by banks and insurers
ASSETS
Debt Securities, Available-for-sale	717	707
Recurring fair value measurements \| Pooled trust preferred securities issued by banks and insurers
ASSETS
Debt Securities, Available-for-sale	1,281	1,329
Recurring fair value measurements \| Small Business Administration Pooled Securities [Member]
ASSETS
Debt Securities, Available-for-sale	60,181	51,927
Recurring fair value measurements \| Loans held for sale
ASSETS
Loans Held-for-sale, Fair Value Disclosure	123,557	6,431
Recurring fair value measurements \| Derivative Financial Instruments, Assets [Member]
ASSETS
Derivative Asset, Fair Value, Gross Asset	80,556	26,310
Recurring fair value measurements \| Derivative instruments
LIABILITIES
Financial and Nonfinancial Liabilities, Fair Value Disclosure	53,679	17,523
Nonrecurring fair value measurements
LIABILITIES
TOTAL NONRECURRING FAIR VALUE MEASUREMENTS	29,360	29,109
Nonrecurring fair value measurements \| Collateral dependent impaired loans
ASSETS
Assets, Fair Value Disclosure	26,471	29,109
Nonrecurring fair value measurements \| Other Real Estate Owned [Member]
ASSETS
Assets, Fair Value Disclosure	2,889
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements
ASSETS
Debt Securities, Trading	1,939	1,504
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS	22,746	20,981
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements \| Equity Securities [Member]
ASSETS
Equity Securities, FV-NI	20,807	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	542,301	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	32,923	32,038
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Agency mortgage-backed securities
ASSETS
Debt Securities, Available-for-sale	197,665	220,105
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Agency collateralized mortgage obligations
ASSETS
Debt Securities, Available-for-sale	98,643	134,911
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Debt Securities, Available-for-sale	1,738	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	717	707
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Small Business Administration Pooled Securities [Member]
ASSETS
Debt Securities, Available-for-sale	60,181	51,927
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Loans held for sale
ASSETS
Loans Held-for-sale, Fair Value Disclosure	123,557	6,431
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Derivative Financial Instruments, Assets [Member]
ASSETS
Derivative Asset, Fair Value, Gross Asset	80,556	26,310
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Derivative instruments
LIABILITIES
Financial and Nonfinancial Liabilities, Fair Value Disclosure	53,679	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	1,281	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	1,281	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	29,360	29,109
Significant Unobservable Inputs (Level 3) \| Nonrecurring fair value measurements \| Collateral dependent impaired loans
ASSETS
Assets, Fair Value Disclosure	26,471	$ 29,109
Significant Unobservable Inputs (Level 3) \| Nonrecurring fair value measurements \| Other Real Estate Owned [Member]
ASSETS
Assets, Fair Value Disclosure	$ 2,889

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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