SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Inventory valuation allowance			$ 700,000	$ 200,000
Allowance for doubtful accounts receivable			600,000	700,000
Short-term investments				0
Excess tax benefit from share-based compensation			$ 300,000	$ 1,100,000	$ 5,900,000
Curtailment gain	$ 14,500,000	$ 2,500,000
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Yield curve, term			0 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Yield curve, term			30 years