Derivative Instruments - Offsetting (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Offsetting Derivative Assets
Gross amounts recognized	$ 446	$ 5
Gross amounts offset in the consolidated balance sheets	0	0
Net amounts presented in the consolidated balance sheets	446	5
Financial instruments	282	5
Financial collateral pledged	0	0
Net amounts	164	0
Offsetting Derivative Liabilities
Gross amounts recognized	6,454	5,182
Gross amounts offset in the consolidated balance sheets	0	0
Net amounts presented in the consolidated balance sheets	6,454	5,182
Financial instruments	282	5
Financial collateral pledged	6,020	4,879
Net amounts	$ 152	$ 298