Restructuring, Impairment and Other Costs - Restructuring and Related Charges (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Restructuring Reserve [Roll Forward]
Accrued beginning balance			$ 770
Costs Incurred, Net of Adjustments	$ 0	$ 0	(639)	$ 0
Payments			(131)
Expenses/ Charges			0
Accrued end balance	0		0
Employee Severance
Restructuring Reserve [Roll Forward]
Accrued beginning balance			0
Costs Incurred, Net of Adjustments			0
Payments			0
Expenses/ Charges			0
Accrued end balance	0		0
Executive Severance
Restructuring Reserve [Roll Forward]
Accrued beginning balance			35
Costs Incurred, Net of Adjustments	0	$ (82)	(711)	$ (899)
Payments			(393)
Expenses/ Charges			0
Accrued end balance	353		353
Facility Closing
Restructuring Reserve [Roll Forward]
Accrued beginning balance			770
Costs Incurred, Net of Adjustments			(639)
Payments			(131)
Expenses/ Charges			0
Accrued end balance	$ 0		$ 0