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Income Taxes - Additional Information (Detail) - USD ($) | 12 Months Ended |
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2021 | Mar. 31, 2023
Income Taxes [Line Items] |  |  |
Deferred income tax asset | $ 2,983,000 |  | $ 2,798,000
Valuation allowance | 5,241,000 |  | 5,277,000
Liability unrecognized tax benefits | 0 |  | $ 0
Investment Tax Credit Carryforward [Member] |  |  |
Income Taxes [Line Items] |  |  |
Deferred income taxes include the impact of state investment tax credits | 236,000 |  |
State investment tax credits with an unlimited carryforward period | $ 794,000 |  |
International Tax Jurisdictions [Member] | Earliest Tax Year [Member] | State Administration of Taxation, China [Member] |  |  |
Income Taxes [Line Items] |  |  |
Open tax year | 2020 |  |
International Tax Jurisdictions [Member] | Earliest Tax Year [Member] | Ministry of Finance, India [Member] |  |  |
Income Taxes [Line Items] |  |  |
Open tax year | 2018 |  |
International Tax Jurisdictions [Member] | Latest Tax Year [Member] | State Administration of Taxation, China [Member] |  |  |
Income Taxes [Line Items] |  |  |
Open tax year | 2023 |  |
International Tax Jurisdictions [Member] | Latest Tax Year [Member] | Ministry of Finance, India [Member] |  |  |
Income Taxes [Line Items] |  |  |
Open tax year | 2022 |  |
Federal Tax Jurisdictions [Member] | Earliest Tax Year [Member] |  |  |
Income Taxes [Line Items] |  |  |
Open tax year | 2020 |  |
Federal Tax Jurisdictions [Member] | Latest Tax Year [Member] |  |  |
Income Taxes [Line Items] |  |  |
Open tax year | 2023 |  |
State Tax Jurisdictions [Member] | Earliest Tax Year [Member] |  |  |
Income Taxes [Line Items] |  |  |
Open tax year | 2019 |  |
State Tax Jurisdictions [Member] | Latest Tax Year [Member] |  |  |
Income Taxes [Line Items] |  |  |
Open tax year | 2023 |  |
Maximum [Member] | Investment Tax Credit Carryforward [Member] |  |  |
Income Taxes [Line Items] |  |  |
Expiration date of state investment tax credits |  | Mar. 31, 2035 |
Minimum [Member] | Investment Tax Credit Carryforward [Member] |  |  |
Income Taxes [Line Items] |  |  |
Expiration date of state investment tax credits |  | Mar. 31, 2022 |

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- Definition The amount of deferred income tax assets pertaining to state investment tax credits that have an unlimited carryforward period. + References No definition available. + Details
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- Definition Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482525/740-10-45-4 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482525/740-10-45-6 + Details
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