Derivatives and Hedging Activities (Offsetting Disclosure for Derivative Contracts) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Offsetting Disclosure for Derivative Contracts [Line Items]
offsetting disclosure, derivative asset, fair value, gross	$ 1,731	$ 5,742	$ 858
offsetting disclosure, offset amount, derivative asset, fair value, gross	0	0	0
offsetting disclosure, net amount, derivative asset, falir value	1,731	5,742	858
offseting disclosure, netting adjustment, derivative asset, fair value	(463)	(380)	(858)
offsetting disclosure, collateral value, derivative asset	(115)	(106)	0
offsetting disclosure, net amount total, derivative asset, fair value	1,153	5,256	0
offsetting disclosure, derivative liability, fair value, gross	50,955	54,725	56,138
offsetting disclosure, offset amount, derivative liability, fair value, gross	0	0	0
offsetting disclosure, net amount, derivative liability, falir value	50,955	54,725	56,138
offseting disclosure, netting adjustment, derivative liability, fair value	(463)	(380)	(858)
offsetting disclosure, collateral value, derivative liability	(50,492)	(54,345)	(55,280)
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	1,153	5,256
offsetting disclosure, offset amount, derivative asset, fair value, gross	0	0
offsetting disclosure, net amount, derivative asset, falir value	1,153	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	1,153	5,256
offsetting disclosure, derivative liability, fair value, gross	5,104	6,683	8,989
offsetting disclosure, offset amount, derivative liability, fair value, gross	0	0	0
offsetting disclosure, net amount, derivative liability, falir value	5,104	6,683	8,989
offseting disclosure, netting adjustment, derivative liability, fair value	0	0	0
offsetting disclosure, collateral value, derivative liability	(5,104)	(6,683)	(8,989)
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	414	352	839
offsetting disclosure, offset amount, derivative asset, fair value, gross	0	0	0
offsetting disclosure, net amount, derivative asset, falir value	414	352	839
offseting disclosure, netting adjustment, derivative asset, fair value	(414)	(352)	(839)
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	45,802	48,014	47,114
offsetting disclosure, offset amount, derivative liability, fair value, gross	0	0	0
offsetting disclosure, net amount, derivative liability, falir value	45,802	48,014	47,114
offseting disclosure, netting adjustment, derivative liability, fair value	(414)	(352)	(839)
offsetting disclosure, collateral value, derivative liability	(45,388)	(47,662)	(46,275)
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	164	134	19
offsetting disclosure, offset amount, derivative asset, fair value, gross	0	0	0
offsetting disclosure, net amount, derivative asset, falir value	164	134	19
offseting disclosure, netting adjustment, derivative asset, fair value	(49)	(28)	(19)
offsetting disclosure, collateral value, derivative asset	(115)	(106)	0
offsetting disclosure, net amount total, derivative asset, fair value	0	0	0
offsetting disclosure, derivative liability, fair value, gross	49	28	35
offsetting disclosure, offset amount, derivative liability, fair value, gross	0	0	0
offsetting disclosure, net amount, derivative liability, falir value	49	28	35
offseting disclosure, netting adjustment, derivative liability, fair value	(49)	(28)	(19)
offsetting disclosure, collateral value, derivative liability	0	0	(16)
offsetting disclosure, net amount total, derivative liability, fair value	$ 0	$ 0	$ 0