ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Sales Reserves (Details) - Reserve for sales returns - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 68	$ 76
Provision related to sales made in current period	1,028	1,037
Adjustment related to sales made in prior periods	5	31
Actual returns or credits related to current period	(959)	(973)
Actual returns or credits related to prior periods	(71)	(103)
Balance at End of Year	$ 71	$ 68