CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Net sales	$ 128,809	$ 144,161	$ 381,614	$ 431,834
Cost of sales	102,234	116,749	306,273	349,050
Gross profit	26,575	27,412	75,341	82,784
Selling, general and administrative expenses	19,385	19,236	55,006	57,598
Impairment of goodwill and other intangible assets	0	0	105,972	0
Gain (loss) on sale of property, plant and equipment	2,099	(55)	2,083	(65)
Restructuring (credits) charges	(20)	814	581	1,316
Income (loss) from operations	9,309	7,307	(84,135)	23,805
Interest expense	(1,538)	(1,792)	(5,243)	(5,965)
Interest income and other, net	243	4,278	466	4,698
Earnings (loss) before (benefit) provision for income taxes	8,014	9,793	(88,912)	22,538
(Benefit) provision for income taxes	(1,696)	4,873	(20,701)	6,236
Net earnings (loss) available to common stockholders	9,710	4,920	(68,211)	16,302
Class A Common Share [Member]
Net earnings (loss) available to common stockholders	$ 1,688	$ 852	$ (12,008)	$ 2,833
Net earnings (loss) per common share:
Common share - basic and diluted (in dollars per share)	$ 0.78	$ 0.39	$ (5.52)	$ 1.30
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 stockholders	$ 8,022	$ 4,068	$ (56,203)	$ 13,469
Net earnings (loss) per common share:
Common share - basic and diluted (in dollars per share)	$ 0.82	$ 0.42	$ (5.78)	$ 1.39
Weighted-average number of shares outstanding:
Common share - basic and diluted (in shares)	9,760	9,719	9,730	9,694
Dividends paid per common share:
Common share (in dollars per share)	$ 0.07	$ 0.07	$ 0.21	$ 0.21

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