STOCK-BASED COMPENSATION - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk free rate	0.30%
Number of shares repurchased (in shares)	0	0
Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price (in dollars per share)	$ 25.78
Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price (in dollars per share)	33.32
Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price (in dollars per share)	$ 34.48
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of options exercised	$ 9.1	$ 0.1
Unrecognized compensation cost	$ 0.3
Weighted average period of recognition for unrecognized compensation expense	10 months 24 days
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 32.3
Change in number of shares earned	2.00%
Maximum percentage of awards to be earned	200.00%
Number of shares earned (in shares)	0
Performance Shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting performance period percentage	0.00%
Total shareholder return performance, lowest percentage to still earn awards	(30.00%)
Performance Shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting performance period percentage	200.00%
Performance Shares \| Tranche One \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting performance period percentage	90.00%
Performance Shares \| Tranche One \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting performance period percentage	110.00%
Stock Exchange Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 8.8
Volatility factors	58.70%
Employee Stock Purchase Plan \| Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 0.6
Weighted average period of recognition for unrecognized compensation expense	1 month 6 days
Number of shares reserved for future issuance (in shares)	2,865,669

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Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Maximum Percentage Of Shares To Be Earned

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Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Change In Shares Earned

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Share-based Compensation Arrangement by Share-based Payment Award, Total Shareholder Return Performance, Lowest Percentage To Still Earn Awards

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Aggregate number of common shares reserved for future issuance.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Price of a single share of a number of saleable stocks of a company.

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Percentage of vesting of award under share-based payment arrangement.

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Number of shares that have been repurchased during the period and are being held in treasury.

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