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Acquisition - Additional Information (Detail) (Energy Steel [Member], USD $) In Thousands, unless otherwise specified | 12 Months Ended
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Mar. 31, 2014 | Mar. 31, 2012 | Mar. 31, 2011 | Mar. 31, 2013 Selling, General and Administrative Expenses [Member] | Mar. 31, 2012 Selling, General and Administrative Expenses [Member] | Mar. 31, 2013 Interest Expense [Member] | Mar. 31, 2012 Interest Expense [Member]
Business Acquisition [Line Items] |  |  |  |  |  |  |
Accounting and purchase price | $ 17,899 |  |  |  |  |  |
Acquisition-related costs |  |  | 676 |  |  |  |
Received from seller due to reduction in purchase price |  | 384 |  |  |  |  |
Purchase agreement included a contingent earn-out, minimum | 0 |  |  |  |  |  |
Purchase agreement included a contingent earn-out, maximum | 2,000 |  |  |  |  |  |
Earn-out paid during period |  | 1,000 |  |  |  |  |
Contingent earn-out liability adjustment |  |  |  | $ (975) | $ 230 | $ 44 | $ 204
Lease term agreement | 5 years |  |  |  |  |  |
Additional lease term agreement | 5 years |  |  |  |  |  |

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- Definition Business acquisition contingent consideration cash paid. + References No definition available. + Details
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- Details
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- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=21917927&loc=d3e1043-128460 + Details
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- Definition Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=7488404&loc=d3e7008-128479 + Details
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- Definition For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=7488404&loc=d3e6927-128479 + Details
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- Definition For contingent consideration arrangements and indemnification assets recognized in connection with a business combination, this element represents an estimate of the low-end of the potential range (undiscounted) of the consideration which may be paid. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=7488404&loc=d3e6927-128479 + Details
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- Definition Term of the lessee's leasing arrangement renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Term of the lessee's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585 + Details
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- Definition Cash inflow representing an adjustment to the purchase price of a previous acquisition. + References No definition available. + Details
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