Debt Debt (Long-term Debt Table) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term debt, gross	$ 350,000	$ 354,798
Unamortized debt issuance costs related to senior secured notes	(6,400)	(8,100)
Long-term debt, net of discount	345,197	349,159
Less: Current portion of long-term debt	0	100
Long-term debt	345,197	349,059
Senior Notes Due 2024 [Member]
Debt Instrument [Line Items]
Long-term debt, gross	350,000	350,000
Revolving Credit Agreement [Member]
Debt Instrument [Line Items]
Long-term debt, gross	0	4,462
Other [Member]
Debt Instrument [Line Items]
Long-term debt, gross	0	336
Senior Notes [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs related to senior secured notes	$ (4,803)	$ (5,639)

Face (par) amount of debt instrument at time of issuance.

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