ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Revenue Recognition (Details)	12 Months Ended
	Dec. 31, 2020
Product Sales and Royalties
Product return period prior to expiration	6 months
Period after expiration for accepting unsalable product	12 months
Cash discount (as a percent)	2.00%
Discount reimbursement period after filling of prescription subject to discount	1 month
Minimum
Product Sales and Royalties
Receivables, collection period	1 month
Product shelf-life	24 months
Discount taken off period after the quarter in which product shipped to the customer	1 month
Period after the quarter in which prescription is filled for paying rebate	2 months
Managed care rebate, period after quarter in which prescription is filled	1 month
Medicare Part D coverage gap rebate, period after quarter in which prescription is filled	2 months
Maximum
Product Sales and Royalties
Receivables, collection period	2 months
Product return period prior to expiration	6 months
Period after expiration for accepting unsalable product	12 months
Product shelf-life	48 months
Discount taken off period after the quarter in which product shipped to the customer	2 months
Period after the quarter in which prescription is filled for paying rebate	3 months
Managed care rebate, period after quarter in which prescription is filled	3 months
Medicare Part D coverage gap rebate, period after quarter in which prescription is filled	3 months