Stock-Based Compensation - Restricted Stock Unit Activity (Details) - $ / shares	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Restricted Stock Units (RSUs)
Restricted Stock Unit Activity
Beginning balance (in shares)	3,162,437	4,261,508
Granted (in shares)	856,756	800,437
Vested (in shares)	(1,141,897)	(874,835)
Forfeited (in shares)	(270,600)	(1,024,673)
Ending balance (in shares)	2,606,696	3,162,437
Weighted Average Fair Value at Grant Date (A$)
Beginning balance (in dollars per share)	$ 14.64	$ 14.47
Granted (in dollars per share)	26.56	18.08
Vested (in dollars per share)	13.03	16.21
Forfeited (in dollars per share)	17.05	15.21
Ending balance (in dollars per share)	$ 19.01	$ 14.64
Restricted Stock Units Service Vesting
Restricted Stock Unit Activity
Beginning balance (in shares)	520,632	910,386
Granted (in shares)	371,806	24,006
Vested (in shares)	(245,385)	(304,591)
Forfeited (in shares)	(53,567)	(109,169)
Ending balance (in shares)	593,486	520,632
Restricted Stock Units Performance Vesting
Restricted Stock Unit Activity
Beginning balance (in shares)	864,165	1,148,022
Granted (in shares)	190,376	273,258
Vested (in shares)	(174,356)	(207,271)
Forfeited (in shares)	(153,897)	(349,844)
Ending balance (in shares)	726,288	864,165
Restricted Stock Units (Market Condition)
Restricted Stock Unit Activity
Beginning balance (in shares)	1,777,640	2,203,100
Granted (in shares)	294,574	503,173
Vested (in shares)	(722,156)	(362,973)
Forfeited (in shares)	(63,136)	(565,660)
Ending balance (in shares)	1,286,922	1,777,640

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

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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 weighted average fair value at grant date for nonvested equity-based awards issued 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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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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 weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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