REVENUE RECOGNITION - Narrative (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Dec. 31, 2018	Mar. 31, 2019
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract with customer, liability, revenue recognized		$ 2.5
Revenue, remaining performance obligation, amount		$ 170.0
Revenue remaining performance obligation, expected timing of satisfaction		24 months
Minimum
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Subscription term	1 year
Maximum
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Subscription term	4 years