Fair Value Measurements (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
ASSETS
Securities - trading	$ 1,298,000	$ 804,000
Securities - available for sale	429,125,000	363,644,000
Loans held for sale (at fair value)	5,459,000	6,139,000
Derivative Asset, Fair Value, Gross Asset	20,029,000	22,331,000
Recurring fair value measurements
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS	436,986,000	371,432,000
Recurring fair value measurements \| Trading Securities [Member]
ASSETS
Securities - trading	1,298,000	804,000
Recurring fair value measurements \| U.S. Government agency securities
ASSETS
Securities - available for sale	23,228,000	24,244,000
Recurring fair value measurements \| Agency mortgage-backed securities
ASSETS
Securities - available for sale	214,564,000	175,384,000
Recurring fair value measurements \| Agency collateralized mortgage obligations
ASSETS
Securities - available for sale	114,829,000	99,868,000
Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Securities - available for sale	2,539,000	3,793,000
Recurring fair value measurements \| Single issuer trust preferred securities issued by banks and insurers
ASSETS
Securities - available for sale	2,044,000	2,311,000
Recurring fair value measurements \| Pooled trust preferred securities issued by banks and insurers
ASSETS
Securities - available for sale	1,624,000	1,584,000
Recurring fair value measurements \| Small Business Administration Pooled Securities [Member]
ASSETS
Securities - available for sale	50,186,000	37,189,000
Recurring fair value measurements \| Equity securities
ASSETS
Securities - available for sale	20,111,000	19,271,000
Recurring fair value measurements \| Loans held for sale
ASSETS
Loans held for sale (at fair value)	5,459,000	6,139,000
Recurring fair value measurements \| Derivative Financial Instruments, Assets [Member]
ASSETS
Derivative Asset, Fair Value, Gross Asset	20,303,000	22,761,000
Recurring fair value measurements \| Derivative instruments
LIABILITIES
Liabilities, Fair Value Disclosure, Recurring	19,199,000	21,916,000
Nonrecurring fair value measurements
LIABILITIES
TOTAL NONRECURRING FAIR VALUE MEASUREMENTS	36,872,000	38,147,000
Nonrecurring fair value measurements \| Collateral dependent impaired loans
ASSETS
Assets, Fair Value Disclosure, Nonrecurring	33,974,000	33,974,000
Nonrecurring fair value measurements \| Other real estate owned and other foreclosed assets
ASSETS
Assets, Fair Value Disclosure, Nonrecurring	2,898,000	4,173,000
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS	21,409,000	20,075,000
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements \| Trading Securities [Member]
ASSETS
Securities - trading	1,298,000	804,000
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
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
Securities - available for sale	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements \| Equity securities
ASSETS
Securities - available for sale	20,111,000	19,271,000
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	413,953,000	349,773,000
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| U.S. Government agency securities
ASSETS
Securities - available for sale	23,228,000	24,244,000
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Agency mortgage-backed securities
ASSETS
Securities - available for sale	214,564,000	175,384,000
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Agency collateralized mortgage obligations
ASSETS
Securities - available for sale	114,829,000	99,868,000
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Securities - available for sale	2,539,000	3,793,000
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Single issuer trust preferred securities issued by banks and insurers
ASSETS
Securities - available for sale	2,044,000	2,311,000
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Small Business Administration Pooled Securities [Member]
ASSETS
Securities - available for sale	50,186,000	37,189,000
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Loans held for sale
ASSETS
Securities - available for sale	5,459,000	6,139,000
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Derivative Financial Instruments, Assets [Member]
ASSETS
Derivative Asset, Fair Value, Gross Asset	20,303,000	22,761,000
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Derivative instruments
LIABILITIES
Liabilities, Fair Value Disclosure, Recurring	19,199,000	21,916,000
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	1,624,000	1,584,000
Significant Unobservable Inputs (Level 3) \| Recurring fair value measurements \| U.S. Government agency securities
ASSETS
Securities - available for sale
Significant Unobservable Inputs (Level 3) \| Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Securities - available for sale		0
Significant Unobservable Inputs (Level 3) \| Recurring fair value measurements \| Pooled trust preferred securities issued by banks and insurers
ASSETS
Securities - available for sale	1,624,000	1,584,000
Significant Unobservable Inputs (Level 3) \| Recurring fair value measurements \| Small Business Administration Pooled Securities [Member]
ASSETS
Securities - available for sale	0	0
Significant Unobservable Inputs (Level 3) \| Nonrecurring fair value measurements
LIABILITIES
TOTAL NONRECURRING FAIR VALUE MEASUREMENTS	36,872,000	38,147,000
Significant Unobservable Inputs (Level 3) \| Nonrecurring fair value measurements \| Collateral dependent impaired loans
ASSETS
Assets, Fair Value Disclosure, Nonrecurring	33,974,000	33,974,000
Significant Unobservable Inputs (Level 3) \| Nonrecurring fair value measurements \| Other real estate owned and other foreclosed assets
ASSETS
Assets, Fair Value Disclosure, Nonrecurring	$ 2,898,000	$ 4,173,000

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Assets and liabilities, fair value disclosure recurring.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Aggregation of the liabilities reported on the balance sheet measured at fair value on a recurring basis by the entity.

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Amount, after allowance for bad debt, of mortgage loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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