Derivatives (Offsetting Derivative Assets and Liabilities Subject to Master Netting Arrangements) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Derivatives [Abstract]
Gross Amounts Recognized, Derivative Assets	$ 4,788	$ 224
Gross Amounts Offset in the Statement of Financial Position, Derivative Assets
Net Amounts Presented in the Statement of Financial Position, Derivative Assets	4,788	224
Gross Amounts Not Offset in the Statement of Financial Position - Financial Instruments, Derivative Assets	4,788	224
Gross Amounts Not offset in the Statement of Financial Position -Cash Collateral, Derivative Assets
Net Amount, Derivative Assets
Gross Amounts Recognized, Derivative Liabilities	26,846	21,034
Net Amounts Presented in the Statement of Financial Position, Derivative Liabilities	26,846	21,034
Gross Amounts Not Offset in the Statement of Financial Position - Financial Instruments, Derivative Liabilities	4,788	224
Gross Amounts Not offset in the Statement of Financial Position -Cash Collateral, Derivative Liabilities	19,095	23,482
Net Amount, Derivative Liabilities	$ 2,963
Net Amount, Derivative Liabilities		$ (2,672)