SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Revenue, Initial Application Period Cumulative Effect Transition (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net revenues	$ 104,301	$ 90,431	$ 79,281	$ 86,453	$ 116,306	$ 93,461	$ 98,701	$ 103,319	$ 360,466	$ 411,788	$ 413,282
Accounts Receivable, after Allowance for Credit Loss, Current	78,614				73,773				78,614	73,773
Inventory, Net	(26,568)				(29,166)				(26,568)	(29,166)
Other Assets, Noncurrent	5,958				6,113				5,958	6,113
Assets	305,138				304,293				305,138	304,293
Accrued Liabilities, Current	42,264				36,759				42,264	36,759
Deferred Revenue, Current	(87,974)				(83,589)				(87,974)	(83,589)
Deferred Revenue, Noncurrent	(11,284)				(14,312)				(11,284)	(14,312)
Liabilities	(438,062)				(459,378)				(438,062)	(459,378)
Retained Earnings (Accumulated Deficit)	(1,168,347)				(1,179,409)				(1,168,347)	(1,179,409)
Stockholders' Equity Attributable to Parent	(132,924)				(155,085)				(132,924)	(155,085)
Cost of Revenue									132,146	162,713	174,118
Gross profit	65,350	58,257	51,562	53,151	73,273	57,858	56,660	61,282	228,320	249,075	239,164
Marketing and selling	22,660	19,998	19,690	25,289	26,603	22,334	26,129	24,878	87,637	99,944	101,273
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest									12,434	2,525	(9,403)
Net (loss) income	$ 7,087	$ 7,987	$ 1,845	$ (5,857)	$ 15,370	$ 3,165	$ (10,723)	$ (213)	$ 11,062	$ 7,601	$ (10,674)