Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net sales	$ 147,930	$ 150,414	$ 297,457	$ 296,287
Costs and expenses:
Cost of materials (exclusive of depreciation)	109,941	111,061	220,899	220,965
Warehouse, processing and delivery expense	20,541	21,165	40,818	41,520
Sales, general and administrative expense	16,477	16,974	32,979	33,522
Depreciation expense	2,130	2,362	4,251	4,738
Total costs and expenses	149,089	151,562	298,947	300,745
Operating loss	(1,159)	(1,148)	(1,490)	(4,458)
Interest expense, net	9,850	8,129	19,299	15,255
Other (income) expense, net	(2,480)	673	(4,082)	(4,101)
Loss before income taxes	(8,529)	(9,950)	(16,707)	(15,612)
Income tax benefit	(225)	(1,437)	(400)	(1,958)
Net loss	$ (8,304)	$ (8,513)	$ (16,307)	$ (13,654)
Basic and diluted loss per common share (in usd per share)	$ (3.77)	$ (4.26)	$ (7.58)	$ (6.83)
Comprehensive loss:
Net loss	$ (8,304)	$ (8,513)	$ (16,307)	$ (13,654)
Change in unrecognized pension and postretirement benefit costs, net of tax	23	0	46	0
Foreign currency translation adjustments, net of tax	(279)	(1,124)	(743)	(1,999)
Comprehensive loss	$ (8,560)	$ (9,637)	$ (17,004)	$ (15,653)