Quarterly report pursuant to Section 13 or 15(d)

REVENUE - Narrative (Details)

v3.19.2
REVENUE - Narrative (Details) - USD ($)
$ in Millions
6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Disaggregation of Revenue [Line Items]    
Actual sales returns rates 3.00% 2.00%
Decrease in deferred revenue, revenue recognized $ 1.5  
Increase in deferred revenue from cash payments received $ 1.2  
Minimum    
Disaggregation of Revenue [Line Items]    
Sales returns policy term 14 days  
Historical sales returns rates 1.00%  
Maximum    
Disaggregation of Revenue [Line Items]    
Sales returns policy term 1 year  
Historical sales returns rates 5.00%