Other Noncurrent Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Other Liabilities Noncurrent [Abstract]
Restricted Insurance Settlements	$ 21,171	$ 21,883
Non-current income taxes payable	15,825	0
Uncertain Tax Positions (Includes Interest and Penalties)	7,970	7,933
Deferred And Other Long-Term Compensation	5,905	5,550
Other	625	520
Total	$ 51,496	$ 35,886