Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Net sales	$ 124,479	$ 146,489	$ 377,284	$ 405,451
Cost of sales	102,021	117,282	311,382	326,096
Gross profit	22,458	29,207	65,902	79,355
Selling, general and administrative expenses	17,909	18,691	56,472	57,690
Impairment of goodwill	8,891		8,891
Restructuring charges	281	17	1,651	62
Gain on sale of property			(4,257)
(Loss) Income from operations	(4,623)	10,499	3,145	21,603
Interest expense	(1,305)	(1,391)	(4,126)	(3,917)
Other income (expense), net	28	43	(361)	(479)
(Loss) Earnings before provision for (benefit from) income taxes	(5,900)	9,151	(1,342)	17,207
Provision for (benefit from) income taxes	590	(2,201)	1,049	523
Net (loss) earnings available to common stockholders	(6,490)	11,352	(2,391)	16,684
Common Class A [Member]
Net (loss) earnings available to common stockholders	$ (1,112)	$ 1,942	$ (442)	$ 2,852
Net (loss) earnings per common share:
Common share - basic and diluted, net earnings (in dollars per share)	$ (0.51)	$ 0.89	$ (0.20)	$ 1.31
Weighted-average number of shares outstanding:
Weighted-average number of common shares outstanding - basic and diluted (in shares)	2,173	2,175	2,174	2,175
Common Class B [Member]
Net (loss) earnings available to common stockholders	$ (5,378)	$ 9,410	$ (1,949)	$ 13,832
Net (loss) earnings per common share:
Common share - basic and diluted, net earnings (in dollars per share)	$ (0.53)	$ 0.94	$ (0.19)	$ 1.40
Weighted-average number of shares outstanding:
Weighted-average number of common shares outstanding - basic and diluted (in shares)	10,139	9,972	10,113	9,891