Derivatives and Hedging Activities (Offsetting Disclosure for Derivative Contracts) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Offsetting Disclosure for Derivative Contracts [Line Items]
offsetting disclosure, derivative asset, fair value, gross	$ 12,754	$ 5,742	$ 1,678
offsetting disclosure, offset amount, derivative asset, fair value, gross	0	0	0
offsetting disclosure, net amount, derivative asset, falir value	12,754	5,742	1,678
offseting disclosure, netting adjustment, derivative asset, fair value	(144)	(380)	(1,498)
offsetting disclosure, collateral value, derivative asset	0	(106)	(180)
offsetting disclosure, net amount total, derivative asset, fair value	12,610	5,256	0
offsetting disclosure, derivative liability, fair value, gross	67,731	54,725	47,023
offsetting disclosure, offset amount, derivative liability, fair value, gross	0	0	0
offsetting disclosure, net amount, derivative liability, falir value	67,731	54,725	47,023
offseting disclosure, netting adjustment, derivative liability, fair value	(144)	(380)	(1,498)
offsetting disclosure, collateral value, derivative liability	(67,587)	(54,345)	(45,525)
offsetting disclosure, net amount total, derivative liability, fair value	0	0	0
Designated as Hedging Instrument | Interest Rate Swap
Offsetting Disclosure for Derivative Contracts [Line Items]
offsetting disclosure, derivative asset, fair value, gross	12,610	5,256
offsetting disclosure, offset amount, derivative asset, fair value, gross	0	0
offsetting disclosure, net amount, derivative asset, falir value	12,610	5,256
offseting disclosure, netting adjustment, derivative asset, fair value	0	0
offsetting disclosure, collateral value, derivative asset	0	0
offsetting disclosure, net amount total, derivative asset, fair value	12,610	5,256
offsetting disclosure, derivative liability, fair value, gross	4,578	6,683	7,584
offsetting disclosure, offset amount, derivative liability, fair value, gross	0	0	0
offsetting disclosure, net amount, derivative liability, falir value	4,578	6,683	7,584
offseting disclosure, netting adjustment, derivative liability, fair value	0	0	0
offsetting disclosure, collateral value, derivative liability	(4,578)	(6,683)	(7,584)
offsetting disclosure, net amount total, derivative liability, fair value	0	0	0
Not Designated as Hedging Instrument | Interest Rate Swap
Offsetting Disclosure for Derivative Contracts [Line Items]
offsetting disclosure, derivative asset, fair value, gross	100	352	1,498
offsetting disclosure, offset amount, derivative asset, fair value, gross	0	0	0
offsetting disclosure, net amount, derivative asset, falir value	100	352	1,498
offseting disclosure, netting adjustment, derivative asset, fair value	(100)	(352)	(1,498)
offsetting disclosure, collateral value, derivative asset	0	0	0
offsetting disclosure, net amount total, derivative asset, fair value	0	0	0
offsetting disclosure, derivative liability, fair value, gross	63,068	48,014	39,439
offsetting disclosure, offset amount, derivative liability, fair value, gross	0	0	0
offsetting disclosure, net amount, derivative liability, falir value	63,068	48,014	39,439
offseting disclosure, netting adjustment, derivative liability, fair value	(100)	(352)	(1,498)
offsetting disclosure, collateral value, derivative liability	(62,968)	(47,662)	(37,941)
offsetting disclosure, net amount total, derivative liability, fair value	0	0	0
Not Designated as Hedging Instrument | Foreign Exchange Contract
Offsetting Disclosure for Derivative Contracts [Line Items]
offsetting disclosure, derivative asset, fair value, gross	44	134	180
offsetting disclosure, offset amount, derivative asset, fair value, gross	0	0	0
offsetting disclosure, net amount, derivative asset, falir value	44	134	180
offseting disclosure, netting adjustment, derivative asset, fair value	(44)	(28)	0
offsetting disclosure, collateral value, derivative asset	0	(106)	(180)
offsetting disclosure, net amount total, derivative asset, fair value	0	0	0
offsetting disclosure, derivative liability, fair value, gross	85	28	0
offsetting disclosure, offset amount, derivative liability, fair value, gross	0	0	0
offsetting disclosure, net amount, derivative liability, falir value	85	28	0
offseting disclosure, netting adjustment, derivative liability, fair value	(44)	(28)	0
offsetting disclosure, collateral value, derivative liability	(41)	0	0
offsetting disclosure, net amount total, derivative liability, fair value	$ 0	$ 0	$ 0