Percentage of granted options vesting five years after the grant date.

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Percentage of granted options vesting three years after the grant date.

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Share-based Compensation Arrangement, Contractual Term

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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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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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The estimated amount of dividends to be paid to holders of the underlying shares (expected dividends) over the option's term. Dividends are taken into account because payment of dividends to shareholders reduces the fair value of the underlying shares, and option holders generally do not receive dividends.

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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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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Percentage of vesting of share-based compensation awards.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Stock-Based Compensation - Narrative (Details) - USD ($)		10 Months Ended	12 Months Ended			40 Months Ended	46 Months Ended
	May 18, 2016	May 21, 2015	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017	Jul. 31, 2014	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense			$ 22,600,000	$ 20,000,000	$ 13,100,000
Tax benefit on stock-based compensation			5,200,000	6,500,000	4,700,000
Excess tax benefit related to stock options exercised			1,900,000	$ 1,300,000	$ 8,300,000
Unrecognized compensation cost			$ 19,500,000				$ 19,500,000
Unrecognized compensation cost, weighted-average period of recognition			1 year 8 months 22 days
Expected dividends			$ 0
Weighted-average grant date fair value (in dollars per share)			$ 10.59	$ 8.12	$ 6.41
Fair value of options vested			$ 12,300,000	$ 16,000,000	$ 5,800,000
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years	3 years	3 years
Performance Shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage			0.00%	0.00%	0.00%
Performance Shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage			200.00%	200.00%	200.00%
Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award maximum term	10 years
Percentage vesting after three years						50.00%
Vesting period		4 years
Percentage vesting after five years						50.00%
Shares authorized to be granted (in shares)	12,150,000
50% Vest After Three Years \| Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period						3 years
50% Vest After Five Years \| Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period						5 years
Options Granted to Directors \| Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years				3 years