Derivative Instruments (Details 2) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Offsetting Derivative Assets
Gross amounts recognized	$ 4,778	$ 446
Gross amounts offset in the consolidated balance sheets	0	0
Net amounts presented in the consolidated balance sheets	4,778	446
Financial instruments	567	282
Financial collateral pledged	0	0
Net amounts	4,211	164
Offsetting Derivative Liabilities
Gross amounts recognized	4,893	6,454
Gross amounts offset in the consolidated balance sheets	0	0
Net amounts presented in the consolidated balance sheets	4,893	6,454
Financial instruments	567	282
Financial collateral pledged	4,326	6,020
Net amounts	$ 0	$ 152

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