ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) $ in Thousands		12 Months Ended
		Dec. 31, 2015 USD ($) Region Period Plan ProductLine	Dec. 31, 2014 USD ($)
ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES [Abstract]
Number of regions in which company sells products | Region		3
Foreign Currency Translation [Abstract]
Transaction gains (losses)		$ (4,200)	$ (3,000)
Cash and Cash Equivalents [Abstract]
Credit card receivables		400	1,200
Cash and cash equivalents held in foreign bank accounts		31,300	24,800
Restricted Cash [Abstract]
Restricted cash		8,100	8,600
Accounts Receivables [Abstract]
Allowance for doubtful accounts		300	200
Other Assets [Abstract]
Other assets		3,759	3,567
Deposits for building leases		1,900	1,500
Fair trade commission deposits		1,600	1,700
Indefinite lived intangible assets		200	200
Notes Payable [Abstract]
Notes payable		1,800
Notes payable, current portion		713	0
Notes payable, long-term portion		1,069	0
Other Long-Term Liabilities [Abstract]
Other long-term liabilities		1,994	2,136
Uncertain income tax positions recorded in noncurrent liabilities		700	800
Accrued lease restoration costs		400	400
Defined benefit plan obligation		(479)	(549)
Revenue Recognition [Abstract]
Deferred revenue		8,700	10,900
Deferred commissions		3,443	4,544
Loyalty Program [Abstract]
Loyalty deferred revenue, beginning balance		9,703	5,456
Loyalty points forfeited		(8,801)	(4,664)
Loyalty points used		(15,077)	(12,348)
Loyalty points vested		20,403	19,580
Loyalty points unvested		1,845	1,679
Loyalty deferred revenue, ending balance		$ 8,073	9,703
Percentage of sale returns		1.50%
Commissions and Incentives Expenses [Abstract]
Number of business periods per year | Period		13
Number of days per business period		28 days
Number of weeks following business period end for payment of product sales commissions		three weeks
Number of weeks following business period end for payment of pack sales commissions		five weeks
Advertising Expenses [Abstract]
Advertising and promotional expense		$ 5,500	4,900
Research and Development Expenses [Abstract]
Research and development consulting fees		$ 1,700	1,600
Stock-Based Compensation [Abstract]
Number of active stock based compensation plan | Plan		1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentages of stock option ownership considered for higher exercise price of option		10.00%
Option exercise price as percentages of closing exercise price of stock for specific shareholders		110.00%
Concentration Risk [Line Items]
Number of products | ProductLine		5
Concentration risk, sales by product		$ 90,886	$ 107,571
Concentration risk, percentage of net sales		50.40%	56.60%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock options		2 years
Percentages of stock option ownership considered for higher exercise price of option		10.00%
Expiration period of stock option plan		5 years
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock options		3 years
Option exercise price as percentages of closing exercise price of stock for specific shareholders		110.00%
Expiration period of stock option plan		10 years
Reserve for Sales Returns [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year		$ 207	$ 238
Provision related to sales made in current period		1,456
Adjustment related to sales made in prior periods		(10)
Actual returns or credits related to current period		(1,319)
Actual returns or credits related to prior periods		(187)
Balance at end of year		$ 147	207
Office Furniture and Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets		5 years
Office Furniture and Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets		7 years
Computer Hardware and Software [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets		3 years
Computer Hardware and Software [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets		5 years
Automobiles [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets		3 years
Automobiles [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets		5 years
Leasehold Improvements [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	[1]	2 years
Leasehold Improvements [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	[1]	10 years
Software [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life of software		3 years
Software [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life of software		5 years
Advanced Ambrotose [Member]
Concentration Risk [Line Items]
Concentration risk, sales by product		$ 59,026	$ 63,791
Concentration risk, percentage of net sales		32.70%	33.60%
Ambrotose [Member]
Concentration Risk [Line Items]
Concentration risk, sales by product		$ 9,686	$ 10,895
Concentration risk, percentage of net sales		5.40%	5.70%
NutriVerus [Member]
Concentration Risk [Line Items]
Concentration risk, sales by product		$ 8,541	$ 10,530
Concentration risk, percentage of net sales		4.70%	5.50%
PLUS [Member]
Concentration Risk [Line Items]
Concentration risk, sales by product		$ 8,239	$ 8,923
Concentration risk, percentage of net sales		4.60%	4.70%
Uth Skin Rejuvenation [Member]
Concentration Risk [Line Items]
Concentration risk, sales by product		$ 5,394	$ 13,431
Concentration risk, percentage of net sales		3.00%	7.10%

[1] The Company amortizes leasehold improvements over the shorter of the useful estimated life of the leased asset or the lease term.