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Income Taxes - Reconciliation of the Provision (Benefit) for Income Taxes (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Mar. 31, 2017
Income Tax Expense Benefit Continuing Operations Income Tax Reconciliation [Abstract] |  |  |
(Benefit) provision for income taxes at federal rate | $ (30) | $ (3,958) | $ 2,467
State taxes | 45 | 118 | 129
Charges not deductible for income tax purposes | 89 | 48 | 39
Recognition of tax benefit generated by qualified production activities deduction |  | 4 | (209)
Research and development tax credits | (177) | (102) | (196)
Valuation allowance | 3,877 | (80) | (26)
Basis difference in subsidiary held for sale | (3,848) |  |
Difference in federal rate | 3 | (2,799) | (194)
Impairment of goodwill and intangible assets | 257 | 1,760 |
Foreign-derived intangible income deduction | (69) |  |
Global intangible low-taxed income | 11 |  |
Stranded tax effects in accumulated other comprehensive loss |  | 1,828 |
Mandatory repatriation of post-1986 undistributed foreign subsidiary earnings and profits |  | 185 |
Other | 5 | (14) | 16
Total provision (benefit) for income taxes | $ 163 | $ (3,010) | $ 2,026

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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 20 -Section 45 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109238882&loc=d3e38679-109324 + Details
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -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 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=84176650&loc=d3e32123-109318 + Details
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to nondeductible expenses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -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://fasb.org/us-gaap/role/ref/legacyRef -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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