Derivatives (Offsetting Derivative Assets and Liabilities Subject to Master Netting Arrangements) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Derivatives [Abstract]
Gross Amounts Recognized, Derivative Assets	$ 1,987	$ 224
Gross Amounts Offset in the Statement of Financial Position, Derivative Assets
Net Amounts Presented in the Statement of Financial Position, Derivative Assets	$ 1,987	$ 224
Gross Amounts Not Offset in the Statement of Financial Position - Financial Instruments, Derivative Assets	$ 1,987	$ 224
Gross Amounts Not offset in the Statement of Financial Position -Cash Collateral, Derivative Assets
Net Amount, Derivative Assets
Gross Amounts Recognized, Derivative Liabilities	$ 33,890	$ 21,034
Gross Amounts Offset in the Statement of Financial Position, Derivative Liabilities
Net Amounts Presented in the Statement of Financial Position, Derivative Liabilities	$ 33,890	$ 21,034
Gross Amounts Not Offset in the Statement of Financial Position - Financial Instruments, Derivative Liabilities	1,987	224
Gross Amounts Not offset in the Statement of Financial Position -Cash Collateral, Derivative Liabilities	33,071	23,482
Net Amount, Derivative Liabilities	$ (1,168)	$ (2,672)