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Business Segments - Schedule of Revenues by Major Customers (Detail) - Total Revenue - Customer Concentration Risk | 3 Months Ended | 9 Months Ended
--- | --- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2015 | Dec. 31, 2014
Inox Wind Limited |  |  |  |
Segment Reporting Asset Reconciling Item [Line Items] |  |  |  |
Revenue percentage | 64.00% | 61.00% | 58.00% | 54.00%
Fuji Bridex Pte Ltd |  |  |  |
Segment Reporting Asset Reconciling Item [Line Items] |  |  |  |
Revenue percentage | 18.00% |  |  |
Fuji Bridex Pte Ltd | Maximum |  |  |  |
Segment Reporting Asset Reconciling Item [Line Items] |  |  |  |
Revenue percentage |  |  | 10.00% |

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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6351-108592 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13531-108611 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6404-108592 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13537-108611 + Details
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