REVENUE - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Mar. 31, 2020
Disaggregation of Revenue [Line Items]
Revenue recognized			$ 165.7
Deferred revenue	$ 335.8		335.8
Unrecognized accounts receivable and deferred revenue	5.7		5.7		$ 11.1
Capitalized contract cost	7.5		7.5		7.2
Amortization of capitalized costs to obtain contracts	1.5	$ 1.6	3.1	$ 3.2
Prepaid Expenses and Other Current Assets
Disaggregation of Revenue [Line Items]
Capitalized contract cost	4.5		4.5		3.9
Other Assets
Disaggregation of Revenue [Line Items]
Capitalized contract cost	$ 3.0		$ 3.0		$ 3.3
Minimum
Disaggregation of Revenue [Line Items]
Payment terms			30 days
Maximum
Disaggregation of Revenue [Line Items]
Payment terms			90 days