Derivatives and Hedging Activities (Customer Related Derivative Positions - Not Designated as Hedges) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Summary of customer related derivative positions, not designated as hedging
Total	$ 75,000,000invest_DerivativeNotionalAmount	$ 75,000,000invest_DerivativeNotionalAmount
Derivative Asset, Fair Value, Gross Asset	28,061,000	22,390,000
Fair Value	(5,370,000)	(5,570,000)
Loan level swaps
Summary of customer related derivative positions, not designated as hedging
Derivative Asset, Fair Value, Gross Asset	23,700,000	18,383,000
Foreign exchange contracts
Summary of customer related derivative positions, not designated as hedging
Derivative Asset, Fair Value, Gross Asset	4,361,000	4,007,000
Not Designated as Hedging Instrument \| Receive fixed, pay variable \| Loan level swaps
Summary of customer related derivative positions, not designated as hedging
Number of Positions	179	174
Less than 1 year	88,082,000	88,147,000
Less than 2 years	48,380,000	46,854,000
Less than 3 years	41,668,000	40,958,000
Less than 4 years	36,072,000	38,108,000
Thereafter	418,153,000	403,208,000
Total	632,355,000	617,275,000
Fair Value	23,692,000	17,840,000
Not Designated as Hedging Instrument \| Pay fixed, receive variable \| Loan level swaps
Summary of customer related derivative positions, not designated as hedging
Number of Positions	173	168
Less than 1 year	88,082,000	88,147,000
Less than 2 years	48,380,000	46,854,000
Less than 3 years	41,668,000	40,958,000
Less than 4 years	36,072,000	38,108,000
Thereafter	418,153,000	403,208,000
Total	632,355,000	617,275,000
Fair Value	(23,691,000)	(17,837,000)
Not Designated as Hedging Instrument \| Buys foreign currency, sells U.S. currency \| Foreign exchange contracts
Summary of customer related derivative positions, not designated as hedging
Number of Positions	21	23
Less than 1 year	29,823,000	57,112,000
Total	29,823,000	57,112,000
Fair Value	4,361,000	4,007,000
Not Designated as Hedging Instrument \| Buys U.S. currency, sells foreign currency \| Foreign exchange contracts
Summary of customer related derivative positions, not designated as hedging
Number of Positions	21	23
Less than 1 year	29,823,000	57,112,000
Total	29,823,000	57,112,000
Fair Value	$ (4,333,000)	$ (3,984,000)

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Notional amount maturing in year five and thereafter.

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Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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The number of derivative instruments of a particular group held by the entity.

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