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Income Taxes - Additional Information (Detail) - USD ($) | 9 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2017 | Mar. 31, 2018 | Mar. 31, 2017
Income Taxes [Line Items] |  |  |
Valuation allowance |  | $ 1,074,000 | $ 959,000
Liability unrecognized tax benefits |  | $ 0 | 0
Percentage of corporate income tax rate | 35.00% | 21.00% |
Income tax benefit from remeasurement of deferred tax assets and liabilities |  | $ 971,000 |
One-time transition tax on accumulated foreign earnings |  | $ 185,000 |
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 |  | 2013 |
Earliest Tax Year [Member] | International Tax Jurisdictions [Member] |  |  |
Income Taxes [Line Items] |  |  |
Open tax year |  | 2014 |
Latest Tax Year [Member] | Federal Tax Jurisdictions [Member] |  |  |
Income Taxes [Line Items] |  |  |
Open tax year |  | 2017 |
Latest Tax Year [Member] | State Tax Jurisdictions [Member] |  |  |
Income Taxes [Line Items] |  |  |
Open tax year |  | 2017 |
Latest Tax Year [Member] | International Tax Jurisdictions [Member] |  |  |
Income Taxes [Line Items] |  |  |
Open tax year |  | 2017 |
Other Assets [Member] |  |  |
Income Taxes [Line Items] |  |  |
Deferred income tax asset foreign |  | $ 15,000 | $ 25,000
Investment Tax Credit Carryforward [Member] |  |  |
Income Taxes [Line Items] |  |  |
Deferred income taxes include the impact of state investment tax credits |  | 279,000 |
State investment tax credits with an unlimited carryforward period |  | $ 795,000 |
Investment Tax Credit Carryforward [Member] | Maximum [Member] |  |  |
Income Taxes [Line Items] |  |  |
Expiration date of state investment tax credits |  | Mar. 31, 2032 |
Investment Tax Credit Carryforward [Member] | Minimum [Member] |  |  |
Income Taxes [Line Items] |  |  |
Expiration date of state investment tax credits |  | Mar. 31, 2019 |

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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 One-time transition tax on accumulated post-1986 earnings and profits of foreign subsidiary previously deferred from U.S. income taxes. + References No definition available. + Details
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
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