CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014		Sep. 30, 2015	Sep. 30, 2014
Net sales	$ 144,161	$ 156,341	[1]	$ 431,834	$ 338,426	[1]
Cost of sales	116,749	128,561	[1]	349,050	278,630	[1]
Gross profit	27,412	27,780	[1]	82,784	59,796	[1]
Selling, general and administrative expenses	19,291	23,110	[1]	57,663	47,475	[1]
Restructuring charges	814	309	[1]	1,316	1,365	[1]
Income from operations	7,307	4,361	[1]	23,805	10,956	[1]
Interest expense	(1,792)	(1,869)	[1]	(5,965)	(2,124)	[1]
Interest income and other, net	4,278	21	[1]	4,698	121	[1]
Earnings before provision for income taxes	9,793	2,513	[1]	22,538	8,953	[1]
Provision for income taxes	4,873	1,252	[1]	6,236	2,124	[1]
Net earnings available to common stockholders	4,920	1,261	[1]	16,302	6,829	[1]
Class A [Member]
Net earnings available to common stockholders	$ 852	$ 211		$ 2,833	$ 1,193
Net earnings per common share:
Common share - basic and diluted (in dollars per share)	$ 0.39	$ 0.10	[1]	$ 1.30	$ 0.55	[1]
Weighted-average number of shares outstanding:
Common share - basic and diluted (in shares)	2,175	2,175	[1]	2,175	2,175	[1]
Dividends paid per common share:
Common share (in dollars per share)	$ 0.06	$ 0.06	[1]	$ 0.18	$ 0.18	[1]
Class B [Member]
Net earnings available to common stockholders	$ 4,068	$ 1,050		$ 13,469	$ 5,636
Net earnings per common share:
Common share - basic and diluted (in dollars per share)	$ 0.42	$ 0.11	[1]	$ 1.39	$ 0.60	[1]
Weighted-average number of shares outstanding:
Common share - basic and diluted (in shares)	9,719	9,591	[1]	9,694	9,420	[1]
Dividends paid per common share:
Common share (in dollars per share)	$ 0.07	$ 0.07	[1]	$ 0.21	$ 0.21	[1]

[1] (Revised)