Derivatives and Hedging Activities (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Derivative [Line Items]
Term of written loan commitments, days	60
Default Assumptions Percentage	100.00%
Credit Derivative, Maximum Exposure, Undiscounted	$ 6,400
Government Agency Issued Bonds or MBS
Derivative [Line Items]
Collateral posted against derivative liabilities	45,100	$ 47,200	$ 53,600
Designated as Hedging Instrument | Interest Rate Swap
Derivative [Line Items]
Derivative Asset, Notional Amount	$ 250,000	$ 250,000	$ 250,000	$ 250,000
Minimum | Equity Swap
Derivative [Line Items]
Maturity of Credit Risk Derivatives	2 years
Minimum | Credit Risk Contract
Derivative [Line Items]
Maturity of Credit Risk Derivatives	1 year
Maximum | Equity Swap
Derivative [Line Items]
Maturity of Credit Risk Derivatives	7 years
Maximum | Credit Risk Contract
Derivative [Line Items]
Maturity of Credit Risk Derivatives	9 years