SELECTED QUARTERLY DATA (UNAUDITED) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended											12 Months Ended
	Dec. 31, 2017		Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016		Mar. 31, 2016		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Selected quarterly financial data [Abstract]
Net sales	$ 119,940		$ 126,386	$ 131,617	$ 113,668	$ 118,539	$ 128,809	$ 131,622		$ 121,182		$ 491,611	$ 500,153	$ 567,080	[1]
Gross profit	22,075		27,617	29,042	23,278	24,579	26,575	25,692		23,074		102,010	99,908	108,827
Net (loss) earnings	(20,787)	[2]	$ 5,024	$ 3,120	$ 746	$ 3,377	$ 9,710	22,776	[3]	(100,696)	[3]	(11,897)	(64,834)	19,197
Net (loss) earnings per share:
Estimated transition tax	17,500
Estimated transition tax, after tax credits	16,000
Revaluation company's deferred tax assets	$ 2,000											6,300
Impairment charges										$ 104,300			106,000
Reversal of provisional non-cash impairment charges								$ (2,600)
Class A Common Stock [Member]
Selected quarterly financial data [Abstract]
Net (loss) earnings												$ (2,113)	$ (11,408)	$ 3,331
Net (loss) earnings per share:
Common share - basic and diluted (in dollars per share)	$ (1.66)		$ 0.40	$ 0.24	$ 0.05	$ 0.27	$ 0.78	$ 1.83		$ (8.15)		$ (0.97)	$ (5.25)	$ 1.53
Class B Common Stock [Member]
Selected quarterly financial data [Abstract]
Net (loss) earnings												$ (9,784)	$ (53,426)	$ 15,866
Net (loss) earnings per share:
Common share - basic and diluted (in dollars per share)	$ (1.74)		$ 0.42	$ 0.26	$ 0.06	$ 0.29	$ 0.82	$ 1.93		$ (8.55)		$ (0.99)	$ (5.48)	$ 1.64

[1] (Revised)

[2] The provision for income taxes in the fourth quarter of 2017 included an $18 million impact from the U.S. Tax Cuts and Jobs Act which was enacted on December 22, 2017. This consisted of an estimated transition tax on foreign earnings of approximately $16 million after the utilization of foreign tax credits and $2 million related to the revaluation of the Company's deferred tax assets.

[3] In connection with an interim impairment test related to the Company's goodwill and other intangible assets, provisional non-cash impairment charges totaling $104.3 million were recorded during the first quarter of 2016. During the second quarter of 2016, the Company finalized its interim impairment test, which resulted in a $2.6 million reduction to the provisional impairment charge recorded during the first quarter.