Balance Sheet Offsetting (Details) - Interest Rate Contract - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	$ 18,031	$ 1,466
Gross amounts offset in the balance sheet	0	0
Net amounts presented in the balance sheet	18,031	1,466
Financial instruments	(18,031)	(1,466)
Collateral	0	0
Net amount	0	0
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	31,075	30,200
Gross amounts offset in the balance sheet	0	0
Net amounts presented in the balance sheet	31,075	30,200
Financial instruments	(18,031)	(1,466)
Collateral	(11,148)	(28,734)
Net amount	$ 1,896	$ 0