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Financial Instruments and Derivative Financial Instruments (Details Textual) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2013 Contract | Mar. 31, 2012 Contract
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Financial Instruments and Derivative Financial Instruments (Additional Textual) [Abstract] |  |
Letters of credit outstanding, amount | $ 12,354 | $ 9,920
Number of foreign exchange forward contracts | 0 | 0
Backlog [Member] | Customer one [Member] |  |
Financial Instruments and Derivative Financial Instruments (Textual) [Abstract] |  |
Concentration of risk percentage for backlog as of the balance sheet date | 21.00% | 24.00%
Backlog [Member] | Customer two [Member] |  |
Financial Instruments and Derivative Financial Instruments (Textual) [Abstract] |  |
Concentration of risk percentage for backlog as of the balance sheet date | 12.00% | 16.00%

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- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. + References No definition available. + Details
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- Definition Number of foreign currency exchange rate derivatives held by the entity at the reporting date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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