Derivative Instruments and Balance Sheet Offsetting (Balance Sheet Offsetting) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Offsetting derivative assets
Gross amounts recognized	$ 17,196	$ 2,018
Offsetting derivative liabilities
Gross amounts recognized	15,970	$ 1,979
Interest rate swaps and customer-initiated derivatives
Offsetting derivative assets
Gross amounts recognized	12,247
Financial instruments	0
Net amounts presented in the statement of financial position	12,247
Gross amounts not offset in the statement of financial position
Financial Instruments	0
Collateral (received)/posted	0
Net Amount	12,247
Offsetting derivative liabilities
Gross amounts recognized	12,785
Financial instruments	0
Net amounts presented in the statement of financial position	12,785
Gross amounts not offset in the statement of financial position
Financial Instruments	0
Collateral (received)/posted	12,530
Net Amount	$ 255