Income Taxes - Reconciliation of Unrecognized Tax Benefits and Interest and Penalties (Detail) - USD ($) |
12 Months Ended | ||
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Mar. 31, 2019 |
Mar. 31, 2018 |
Mar. 31, 2017 |
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| Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] | |||
| Unrecognized tax benefits, Beginning balance | $ 700,000 | $ 700,000 | $ 700,000 |
| Unrecognized tax benefits, Additions for tax positions of the current year | 100,000 | 0 | 100,000 |
| Interest and penalties recognized income tax expense | 100,000.0 | 0 | 0 |
| Unrecognized tax benefits, Reductions in tax positions of prior year | 0 | 0 | (100,000) |
| Unrecognized tax benefits, Ending Balance | 600,000 | 700,000 | 700,000 |
| Interest and Penalties, Beginning balance | 0 | 0 | 0 |
| Interest And Penalties, Reductions in tax position of prior year | 0 | ||
| Interest and Penalties, Ending Balance | 100,000.0 | $ 0 | $ 0 |
| Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations | $ (200,000) | ||
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- Definition Interest and penalties additions deletions for tax positions of prior year. No definition available.
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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