STOCK-BASED COMPENSATION - Schedule of Stock-Based Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Allocation of stock-based compensation expense
Total stock-based compensation expense	$ 23.0	$ 19.8	$ 71.7	$ 62.9
Cost of sales
Allocation of stock-based compensation expense
Total stock-based compensation expense	4.3	3.6	13.6	11.5
Selling, general, and administrative expenses
Allocation of stock-based compensation expense
Total stock-based compensation expense	13.8	12.4	43.5	39.4
Research and development expenses
Allocation of stock-based compensation expense
Total stock-based compensation expense	$ 4.9	$ 3.8	$ 14.6	$ 12.0