Derivatives and Hedging Activities (Designated as Hedging Instruments, Notional Values, Contractual Amounts and Fair Value) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Derivatives designated in hedge relationships
Derivative Asset, Fair Value	$ 76,196	$ 55,197	$ 43,097
Derivative Liability, Fair Value	67,936	55,439	49,280
Commercial Loan Swaps (FRAPS) | Designated as Hedging Instrument
Derivatives designated in hedge relationships
Derivative Asset, Notional/Contract Amount	0	0	0
Derivative Asset, Fair Value	0	0	0
Derivative Liability, Notional/Contract Amount	69,136	93,313	100,490
Derivative Liability, Fair Value	4,578	6,683	7,584
Sub Debt Swap | Designated as Hedging Instrument
Derivatives designated in hedge relationships
Derivative Asset, Notional/Contract Amount	250,000	250,000	0
Derivative Asset, Fair Value	12,610	5,256	0
Derivative Liability, Notional/Contract Amount	0	0	0
Derivative Liability, Fair Value	0	0	0
Interest rate swaps | Designated as Hedging Instrument
Derivatives designated in hedge relationships
Derivative Asset, Notional/Contract Amount	250,000	250,000	0
Derivative Asset, Fair Value	12,610	5,256	0
Derivative Liability, Notional/Contract Amount	69,136	93,313	100,490
Derivative Liability, Fair Value	4,578	6,683	7,584
Level 2
Derivatives designated in hedge relationships
Derivative Asset, Fair Value	76,196	55,197	43,097
Derivative Liability, Fair Value	67,936	55,439	48,765
Level 2 | Interest rate swaps | Designated as Hedging Instrument
Derivatives designated in hedge relationships
Derivative Asset, Fair Value	12,610	5,256	0
Derivative Liability, Fair Value	$ 4,578	$ 6,683	$ 7,584