Derivative Instruments and Hedging Activities (Details 2) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Disclosure of Offsetting Assets and Liabilities [Abstract]
Derivative Assets, Fair Value, Gross Assets	$ 29,320	$ 96
Gross Amount of Eligible Offsetting Recognized Derivative Liabilities	(64)	(96)
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	29,256	0
Derivative Asset, Not Offset, Policy Election Deduction	(11,195)	0
Cash Collateral Received	(10,724)	0
Derivative Asset, Fair Value, Amount Offset Against Collateral	7,337	0
Derivative Liability, Fair Value, Gross Liability	(20,157)	(178)
Gross Amount of Eligible Offsetting Recognized Derivative Assets	64	96
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(20,093)	(82)
Derivative Liability, Not Offset, Policy Election Deduction	11,195	0
Cash Collateral Paid	5,798	0
Derivative Liability, Fair Value, Amount Offset Against Collateral	$ (3,100)	$ (82)