CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Net sales	$ 126,386	$ 128,809	$ 371,671	$ 381,614
Cost of sales	98,769	102,234	291,729	306,273
Gross profit	27,617	26,575	79,942	75,341
Selling, general and administrative expenses	20,903	19,385	63,858	55,006
Impairment of goodwill and other intangible assets	0	0	0	105,972
Loss (gain) on disposal of property, plant and equipment	182	(2,099)	283	(2,083)
Restructuring charges (credits)	0	(20)	171	581
Income (loss) from operations	6,532	9,309	15,630	(84,135)
Interest expense	(1,466)	(1,538)	(4,476)	(5,243)
Interest income and other, net	18	243	65	466
Earnings (loss) before provision for (benefit from) income taxes	5,084	8,014	11,219	(88,912)
Provision for (benefit from) income taxes	60	(1,696)	2,329	(20,701)
Net earnings (loss) available to common shareholders	5,024	9,710	8,890	(68,211)
Class A Common Share [Member]
Net earnings (loss) available to common shareholders	$ 860	$ 1,688	$ 1,507	$ (12,008)
Net earnings (loss) per common share:
Common share - basic and diluted (in dollars per share)	$ 0.40	$ 0.78	$ 0.69	$ (5.52)
Weighted-average number of shares outstanding:
Common share - basic and diluted (in shares)	2,175	2,175	2,175	2,175
Dividends paid per common share:
Common share (in dollars per share)	$ 0.06	$ 0.06	$ 0.18	$ 0.18
Class B Common Share [Member]
Net earnings (loss) available to common shareholders	$ 4,164	$ 8,022	$ 7,383	$ (56,203)
Net earnings (loss) per common share:
Common share - basic and diluted (in dollars per share)	$ 0.42	$ 0.82	$ 0.75	$ (5.78)
Weighted-average number of shares outstanding:
Common share - basic and diluted (in shares)	9,864	9,760	9,856	9,730
Dividends paid per common share:
Common share (in dollars per share)	$ 0.07	$ 0.07	$ 0.21	$ 0.21

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