Recurring and Nonrecurring basis (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading	$ 1,500	$ 1,300
Equity Securities, FV-NI	19,477	0
Debt Securities, Available-for-sale	442,752	447,498
Assets
Disposal Group, Including Discontinued Operation, Mortgage Loans	6,431	4,768
Total	26,113	17,318
Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	0	20,584
U.S. Government agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	32,038	35,430
Agency mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	220,105	215,764
Pooled trust preferred securities issued by banks and insurers
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	1,329	1,640
Small Business Administration Pooled Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	51,927	47,778
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading	1,504	1,324
Liabilities
Total recurring fair value measurements	478,951	455,373
Fair Value, Measurements, Recurring [Member] \| Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	19,477
Assets
Securities - available for sale		20,584
Fair Value, Measurements, Recurring [Member] \| U.S. Government agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	32,038	35,430
Fair Value, Measurements, Recurring [Member] \| Agency mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	220,105	215,764
Fair Value, Measurements, Recurring [Member] \| Agency collateralized mortgage obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	134,911	122,012
Fair Value, Measurements, Recurring [Member] \| State, county, and municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	1,735	2,274
Fair Value, Measurements, Recurring [Member] \| Single issuer trust preferred securities issued by banks and insurers
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	707	2,016
Fair Value, Measurements, Recurring [Member] \| Pooled trust preferred securities issued by banks and insurers
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	1,329	1,640
Fair Value, Measurements, Recurring [Member] \| Small Business Administration Pooled Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	51,927	47,778
Fair Value, Measurements, Recurring [Member] \| Loans held for sale
Assets
Disposal Group, Including Discontinued Operation, Mortgage Loans	6,431	4,768
Fair Value, Measurements, Recurring [Member] \| Derivative instruments
Assets
Total	26,310	17,476
Fair Value, Measurements, Recurring [Member] \| Derivative instruments
Assets
Financial and Nonfinancial Liabilities, Fair Value Disclosure	17,523	15,693
Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading	1,504	1,324
Liabilities
Total recurring fair value measurements	20,981	21,908
Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	19,477
Assets
Securities - available for sale		20,584
Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| State, county, and municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale		0
Fair Value, Measurements, Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Small Business Administration Pooled Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	0	0
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Liabilities
Total recurring fair value measurements	456,641	431,825
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	0
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| U.S. Government agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	32,038	35,430
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Agency mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	220,105	215,764
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Agency collateralized mortgage obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	134,911	122,012
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| State, county, and municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	1,735	2,274
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Single issuer trust preferred securities issued by banks and insurers
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	707	2,016
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Small Business Administration Pooled Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	51,927	47,778
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Loans held for sale
Assets
Securities - available for sale	6,431	4,768
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Derivative instruments
Assets
Total	26,310	17,476
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Derivative instruments
Assets
Financial and Nonfinancial Liabilities, Fair Value Disclosure	17,523	15,693
Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Liabilities
Total recurring fair value measurements	1,329	1,640
Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI	0
Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| State, county, and municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale		0
Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Pooled trust preferred securities issued by banks and insurers
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	1,329	1,640
Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Small Business Administration Pooled Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	0	0
Fair Value, Measurements, Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Other real estate owned and other foreclosed assets
Liabilities
Assets, Fair Value Disclosure	0	612
Fair Value, Measurements, Nonrecurring [Member]
Assets
Assets And Liabilities Fair Value Disclosure Nonrecurring	29,109	34,179
Fair Value, Measurements, Nonrecurring [Member] \| Collateral dependent impaired loans
Liabilities
Assets, Fair Value Disclosure	29,109	33,567
Fair Value, Measurements, Nonrecurring [Member] \| Other real estate owned and other foreclosed assets
Liabilities
Assets, Fair Value Disclosure		612
Fair Value, Measurements, Nonrecurring [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Assets
Assets And Liabilities Fair Value Disclosure Nonrecurring	29,109	34,179
Fair Value, Measurements, Nonrecurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Collateral dependent impaired loans
Liabilities
Assets, Fair Value Disclosure	$ 29,109	33,567
Fair Value, Measurements, Nonrecurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Other real estate owned and other foreclosed assets
Liabilities
Assets, Fair Value Disclosure		$ 612

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