Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
ASSETS
Trading Securities	$ 494us-gaap_TradingSecurities
Securities - available for sale	387,038us-gaap_AvailableForSaleSecurities	348,554us-gaap_AvailableForSaleSecurities
Disposal Group, Including Discontinued Operation, Mortgage Loans	9,507us-gaap_LoansHeldForSaleMortgages	6,888us-gaap_LoansHeldForSaleMortgages
Derivative Asset, Fair Value, Gross Asset	28,061	22,390
Recurring fair value measurements
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS	392,172	350,180
Recurring fair value measurements \| Trading Securities [Member]
ASSETS
Trading Securities	494
Recurring fair value measurements \| U.S. Government agency securities
ASSETS
Securities - available for sale	46,504	41,486
Recurring fair value measurements \| Agency mortgage-backed securities
ASSETS
Securities - available for sale	254,089	217,678
Recurring fair value measurements \| Agency collateralized mortgage obligations
ASSETS
Securities - available for sale	60,288	63,035
Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Securities - available for sale	4,977	5,223
Recurring fair value measurements \| Single issuer trust preferred securities issued by banks and insurers
ASSETS
Securities - available for sale	2,910	2,909
Recurring fair value measurements \| Pooled trust preferred securities issued by banks and insurers
ASSETS
Securities - available for sale	6,272	6,321
Recurring fair value measurements \| Equity securities
ASSETS
Securities - available for sale	11,998	11,902
Recurring fair value measurements \| Loans held for sale
ASSETS
Disposal Group, Including Discontinued Operation, Mortgage Loans	9,507	6,888
Recurring fair value measurements \| Derivative Financial Instruments, Assets [Member]
ASSETS
Derivative Asset, Fair Value, Gross Asset	28,535	22,688
Recurring fair value measurements \| Derivative Instruments
LIABILITIES
Liabilities, Fair Value Disclosure, Recurring	33,402	27,950
Nonrecurring fair value measurements
LIABILITIES
TOTAL NONRECURRING FAIR VALUE MEASUREMENTS	13,844	15,939
Nonrecurring fair value measurements \| Collateral dependent impaired loans
ASSETS
Assets, Fair Value Disclosure, Nonrecurring	7,559	8,196
Nonrecurring fair value measurements \| Other real estate owned and other foreclosed assets
ASSETS
Assets, Fair Value Disclosure, Nonrecurring	6,285	7,743
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS	12,492	11,902
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements \| Trading Securities [Member]
ASSETS
Trading Securities	494
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Recurring fair value measurements \| Equity securities
ASSETS
Securities - available for sale	11,998	11,902
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS	373,408	331,957
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| U.S. Government agency securities
ASSETS
Securities - available for sale	46,504	41,486
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Agency mortgage-backed securities
ASSETS
Securities - available for sale	254,089	217,678
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Agency collateralized mortgage obligations
ASSETS
Securities - available for sale	60,288	63,035
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Municipal Bonds [Member]
ASSETS
Securities - available for sale	4,977	5,223
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	2,910	2,909
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Loans held for sale
ASSETS
Securities - available for sale	9,507	6,888
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Derivative Financial Instruments, Assets [Member]
ASSETS
Derivative Asset, Fair Value, Gross Asset	28,535	22,688
Significant Other Observable Inputs (Level 2) \| Recurring fair value measurements \| Derivative Instruments
LIABILITIES
Liabilities, Fair Value Disclosure, Recurring	33,402	27,950
Significant Unobservable Inputs (Level 3) \| Recurring fair value measurements
LIABILITIES
TOTAL RECURRING FAIR VALUE MEASUREMENTS	6,272	6,321
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 \| Pooled trust preferred securities issued by banks and insurers
ASSETS
Securities - available for sale	6,272	6,321
Significant Unobservable Inputs (Level 3) \| Nonrecurring fair value measurements
LIABILITIES
TOTAL NONRECURRING FAIR VALUE MEASUREMENTS	13,844	15,939
Significant Unobservable Inputs (Level 3) \| Nonrecurring fair value measurements \| Collateral dependent impaired loans
ASSETS
Assets, Fair Value Disclosure, Nonrecurring	7,559	8,196
Significant Unobservable Inputs (Level 3) \| Nonrecurring fair value measurements \| Other real estate owned and other foreclosed assets
ASSETS
Assets, Fair Value Disclosure, Nonrecurring	$ 6,285	$ 7,743

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

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Amount classified as mortgage loans attributable to disposal group held for sale or disposed of. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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