Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Allowance for doubtful accounts
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 122	$ 489	$ 104
Charged (Credited) to Costs and Expenses	333	(246)	569
Charged to Other Accounts	84	0	0
Write-offs/Deductions	(56)	(121)	(184)
Balance at End of Year	483	122	489
Valuation allowance for deferred taxes
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	61,702	50,160	58,350
Charged (Credited) to Costs and Expenses	16,637	11,542	(8,190)
Charged to Other Accounts	0	0	0
Write-offs/Deductions	0	0	0
Balance at End of Year	$ 78,339	$ 61,702	$ 50,160

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 valuation and qualifying accounts and reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09(Column B))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09(Column E))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690

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Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

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Amount of increase in valuation and qualifying accounts and reserves from charge to accounts other than cost and expense.

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