Derivatives and Hedging Activities (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Derivative [Line Items]
Term of written loan commitments, days
Default Assumptions Percentage	100.00%	100.00%
Government Agency Issued Bonds or MBS
Derivative [Line Items]
Collateral posted against derivative liabilities	$ 45,600	$ 45,600	$ 53,500	$ 64,000
Designated as Hedging Instrument | Interest Rate Swap
Derivative [Line Items]
Derivative Asset, Notional Amount	$ 250,000	$ 250,000	$ 250,000	$ 0
Minimum [Member] | Equity Swap
Derivative [Line Items]
Maturity of Credit Risk Derivatives		3 years
Minimum [Member] | Credit Risk Contract
Derivative [Line Items]
Maturity of Credit Risk Derivatives		1 year
Maximum [Member] | Equity Swap
Derivative [Line Items]
Maturity of Credit Risk Derivatives		8 years
Maximum [Member] | Credit Risk Contract
Derivative [Line Items]
Maturity of Credit Risk Derivatives		9 years