Employee Benefit Plans Amounts Recognized in Accumulated Other Comprehensive Income (Loss) (Details) - Pension Plans, Defined Benefit [Member] - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), after Tax
Unrecognized prior service cost	$ 60	$ 80
Unrecognized net loss/(gain)	17,910	18,570
Total accumulated other comprehensive income (loss) recognized at December 31	$ 17,970	$ 18,650