Summary of Significant Accounting Policies Summary of Significant Accounting Policies - Reclassification (Details 10) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Other current assets	$ 10,638	$ 9,863
Deferred income taxes	45,839	63,809
Accrued Liabilities, Current	$ (45,708)	(47,174)
Pension and Other Postretirement and Postemployment Benefit Plans, Liabilities, Noncurrent		(7,230)
Liabilities, Other than Long-term Debt, Noncurrent		(9,169)
Scenario, Previously Reported [Member]
Other current assets		15,888
Deferred income taxes		58,544
Accrued Liabilities, Current		(53,905)
Pension and Other Postretirement and Postemployment Benefit Plans, Liabilities, Noncurrent		(2,703)
Liabilities, Other than Long-term Debt, Noncurrent		(7,725)
Restatement Adjustment [Member]
Other current assets		(6,025)
Deferred income taxes		5,265
Accrued Liabilities, Current		(6,731)
Pension and Other Postretirement and Postemployment Benefit Plans, Liabilities, Noncurrent		4,527
Liabilities, Other than Long-term Debt, Noncurrent		$ 1,444