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Income Taxes - Additional Information (Detail) - USD ($) | 6 Months Ended |
--- | --- | ---
Sep. 30, 2019 | Mar. 31, 2019
Income Taxes [Line Items] |  |
Liability unrecognized tax benefits | $ 0 | $ 0
Earliest Tax Year [Member] | Federal Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2015 |
Earliest Tax Year [Member] | State Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2014 |
Earliest Tax Year [Member] | International Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2016 |
Latest Tax Year [Member] | Federal Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2018 |
Latest Tax Year [Member] | State Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2018 |
Latest Tax Year [Member] | International Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2018 |

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- Definition Tax year that remains open to examination under enacted tax laws, in CCYY format. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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