Revenue from Contracts with Customers Financial Statement Impact of Adopting ASC 606 (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net sales	$ 199,477	$ 205,683	$ 196,349	$ 169,148	$ 156,135	$ 148,156	$ 157,947	$ 157,555	$ 770,657	$ 619,793	$ 584,954
Cost of sales									588,205
Income (loss) from operations									(178,888)	33,114	$ 34,779
Accounts receivable, net	133,421								133,421
Inventories	122,615				$ 82,617				122,615	$ 82,617
Calculated under Revenue Guidance in Effect before Topic 606
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net sales									770,654
Cost of sales									588,202
Income (loss) from operations									(178,888)
Accounts receivable, net	132,810								132,810
Inventories	122,988								122,988
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net sales									3
Cost of sales									3
Income (loss) from operations									0
Accounts receivable, net	611								611
Inventories	$ (373)								$ (373)