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Income Taxes - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified | 12 Months Ended |
--- | --- | ---
Mar. 31, 2014 | Mar. 31, 2013 | Dec. 31, 2012 | Mar. 31, 2012
Income Taxes [Line Items] |  |  |  |
Deferred income taxes include the impact of state investment tax credits | $ 298 |  |  |
State investment tax credits with an unlimited carryforward period | 440 |  |  |
Valuation allowance | 738 | 564 |  |
Liability unrecognized tax benefits | 0 | 134 |  | 1,787
Reduction in liability for unrecognized tax benefits | 134 | 893 |  |
Unrecognized tax benefits, reversal of interest expense on income taxes | (11) | (320) |  |
Unrecognized tax benefits, interest expense on income taxes |  |  | 259 |
Penalties related to uncertain tax positions | $ 0 | $ 0 | $ 0 |
Maximum [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Expire date of state investment tax credits | 2028 |  |  |
Maximum [Member] | Internal Revenue Service (IRS) [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Federal and State tax jurisdictions for tax period | 2012 |  |  |
Maximum [Member] | Federal Tax Jurisdictions [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Federal and State tax jurisdictions for tax period | 2013 |  |  |
Maximum [Member] | State Tax Jurisdictions [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Federal and State tax jurisdictions for tax period | 2013 |  |  |
Maximum [Member] | International Tax Jurisdictions [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Federal and State tax jurisdictions for tax period | 2013 |  |  |
Minimum [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Expire date of state investment tax credits | 2015 |  |  |
Minimum [Member] | Internal Revenue Service (IRS) [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Federal and State tax jurisdictions for tax period | 2011 |  |  |
Minimum [Member] | Federal Tax Jurisdictions [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Federal and State tax jurisdictions for tax period | 2011 |  |  |
Minimum [Member] | State Tax Jurisdictions [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Federal and State tax jurisdictions for tax period | 2009 |  |  |
Minimum [Member] | International Tax Jurisdictions [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Federal and State tax jurisdictions for tax period | 2011 |  |  |

X
- Definition Tax year in which the examination by the taxing authority is complete. + References No definition available. + Details
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- Definition Deferred tax assets tax deferred expense state investment tax credit expiration period. + References No definition available. + Details
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- Definition The amount of deferred income tax assets pertaining to state investment tax credits that have expiration dates. + References No definition available. + Details
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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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- Details
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- Definition Amount of interest expense reversed that was recorded in a prior period related to unrecognized tax benefits. + 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=6907707&loc=d3e32537-109319 + Details
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- Definition Tax year that remains open to examination under enacted tax laws, in CCYY format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 + Details
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- Definition Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Unrecognized Tax Benefit -URI http://asc.fasb.org/extlink&oid=6527854 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319 + Details
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15A -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319 + Details
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- Definition Amount of expense for penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 + Details
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- Definition Amount of interest expense for an underpayment of income taxes. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 + Details
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