Condensed Consolidated Statements of Operations and Comprehensive Income (Loss) (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
Net sales	$ 205,683	$ 148,156	$ 571,180	$ 463,658
Cost of sales (exclusive of depreciation and amortization shown separately below)	156,408	111,272	431,492	340,266
Selling, general and administrative expense	22,480	16,985	71,298	51,630
Acquisition related costs excluded from selling, general and administrative expense	597	619	5,810	619
Depreciation and amortization	21,259	13,384	51,798	39,006
Other operating income, net	(733)	0	(638)	(270)
Restructuring and integration expense (adjustments), net	(209)	345	2,137	362
Income from operations	5,881	5,551	9,283	32,045
Interest expense	18,608	12,739	46,592	39,916
Loss on extinguishment of debt and write-off of debt issuance costs	6,624	0	19,562	39,639
Derivative gain on change in interest rate swap fair value	0	(27)	0	(14)
Other (income) expense, net	308	(755)	1,882	(1,192)
Loss from continuing operations before benefit for income taxes and share of net income from joint venture	(19,659)	(6,406)	(58,753)	(46,304)
Benefit for income taxes	5,609	1,724	12,732	14,204
Share of net income from joint venture	266	1,202	1,744	4,139
Loss from continuing operations	(13,784)	(3,480)	(44,277)	(27,961)
Income from discontinued operations, net of tax (Note 2)	0	129,441	0	140,195
Net income (loss)	(13,784)	125,961	(44,277)	112,234
Reclassification adjustment for discontinued operations	0	(9,243)	0	(9,243)
Other comprehensive income (loss):
Foreign currency translation gain (loss)	(4,193)	6,411	(14,509)	21,027
Other comprehensive income (loss)	(4,193)	(2,832)	(14,509)	11,784
Comprehensive income (loss)	$ (17,977)	$ 123,129	$ (58,786)	$ 124,018
Basic net loss per share:
Loss from continuing operations per share	$ (0.48)	$ (0.13)	$ (1.59)	$ (1.02)
Income from discontinued operations per share	0.00	4.70	0.00	5.12
Net income (loss) per share	$ (0.48)	$ 4.57	$ (1.59)	$ 4.10
Weighted average shares outstanding	28,688	27,544	27,784	27,403
Diluted net loss per share:
Loss from continuing operations per share	$ (0.48)	$ (0.13)	$ (1.59)	$ (1.02)
Income from discontinued operations per share	0.00	4.70	0.00	5.12
Net income (loss) per share	$ (0.48)	$ 4.57	$ (1.59)	$ 4.10
Weighted average shares outstanding	28,688	27,544	27,784	27,403