Balance Sheet Offsetting (Details) - Interest Rate Contract [Member] - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Offsetting Derivative Assets [Abstract]
Gross amounts recognized	$ 278	$ 558
Gross amounts offset in the balance sheet	0	0
Net amounts presented in the balance sheet	278	558
Financial instruments	(278)	(558)
Collateral	0	0
Net amount	0	0
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	32,372	34,087
Gross amounts offset in the balance sheet	0	0
Net amounts presented in the balance sheet	32,372	34,087
Financial instruments	(278)	(558)
Collateral	(25,684)	(26,105)
Net amount	$ 6,410	$ 7,424