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v3.20.1

Stock-Based Compensation - Schedule of Stock-Based Compensation Expense (Detail) - USD ($) $ in Millions | 12 Months Ended
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Mar. 31, 2020 | Mar. 31, 2019 | Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] |  |  |
Total stock-based compensation expense | $ 13.1 | $ 11.9 | $ 16.7
Liability Awards Expense [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] |  |  |
Total stock-based compensation expense | 2.8 | (0.6) | 5.6
Equity Awards Expense [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] |  |  |
Total stock-based compensation expense | $ 10.3 | $ 12.5 | $ 11.1

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- Definition Amount of expense for employee benefit and equity-based compensation. + References No definition available. + Details
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Period Type: | duration

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- Definition 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. + References No definition available. + Details
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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |