SHARE-BASED COMPENSATION - Additional Information (Details) $ / shares in Units, $ in Millions	9 Months Ended
Dec. 31, 2018 USD ($) $ / shares shares
Share options
Share-based compensation
Compensation not yet recognized \| $	$ 3.1
Share weighted-average remaining vesting period	1 year 9 months 18 days
Share options outstanding (shares)	1,000,000
Options exercisable (shares)	600,000
Options outstanding, weighted average exercise price (usd per share) \| $ / shares	$ 3.67
Weighted average exercise price of exercisable shares (usd per share) \| $ / shares	$ 4.69
Restricted Stock Units, Share Bonus Awards with Market Conditions, and Share Bonus Awards With Free Cash Flow Targets
Share-based compensation
Share weighted-average remaining vesting period	2 years 7 months 6 days
Unvested share bonus awards granted (shares)	6,300,000
Number of shares outstanding (shares)	14,500,000
Unrecognized compensation expense \| $	$ 144.7
Restricted Stock Units
Share-based compensation
Unvested share bonus awards granted (shares)	4,600,000
Average grant date price of unvested share bonus awards (usd per share) \| $ / shares	$ 13.53
Vesting period	4 years
Share Bonus Awards with Market Conditions
Share-based compensation
Number of shares outstanding (shares)	2,600,000
Share Bonus Awards with Market Conditions \| Fiscal 2016
Share-based compensation
Shares vested (shares)	600,000
Share Bonus Awards with Market Conditions \| Minimum
Share-based compensation
Number of shares that may be issued (shares)	0
Share Bonus Awards with Market Conditions \| Maximum
Share-based compensation
Number of shares that may be issued (shares)	5,200,000
Share Bonus Awards with Market Conditions \| Key employees
Share-based compensation
Unvested share bonus awards granted (shares)	1,300,000
Average grant date price of unvested share bonus awards (usd per share) \| $ / shares	$ 14.00
Vesting period	3 years
Share Bonus Awards with Market Conditions \| Key employees \| Minimum
Share-based compensation
Unvested share bonus awards granted (shares)	0
Share Bonus Awards with Market Conditions \| Key employees \| Maximum
Share-based compensation
Unvested share bonus awards granted (shares)	2,600,000.0

Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested options awarded to employees as compensation.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of share instruments newly issued under a share-based compensation plan.

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