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Business Segments - Schedule of Revenues by Major Customers (Detail) - Total revenue - Customer concentration risk | 3 Months Ended
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Jun. 30, 2017 | Jun. 30, 2016
INOX Wind Limited |  |
Segment Reporting Asset Reconciling Item [Line Items] |  |
Concentration risk, revenue (less than 10% for Essential Energy and Reed & Reed Inc. for the three months ended June 2017) | 22.00% | 27.00%
U.S. Navy |  |
Segment Reporting Asset Reconciling Item [Line Items] |  |
Concentration risk, revenue (less than 10% for Essential Energy and Reed & Reed Inc. for the three months ended June 2017) | 35.00% | 0.00%
Reed & Reed Inc. |  |
Segment Reporting Asset Reconciling Item [Line Items] |  |
Concentration risk, revenue (less than 10% for Essential Energy and Reed & Reed Inc. for the three months ended June 2017) | 10.00% | 17.00%
Essential Energy |  |
Segment Reporting Asset Reconciling Item [Line Items] |  |
Concentration risk, revenue (less than 10% for Essential Energy and Reed & Reed Inc. for the three months ended June 2017) | 10.00% | 13.00%
XJ Group Corporation |  |
Segment Reporting Asset Reconciling Item [Line Items] |  |
Concentration risk, revenue (less than 10% for Essential Energy and Reed & Reed Inc. for the three months ended June 2017) | 0.00% | 12.00%

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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=84177426&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=77997519&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=84177426&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=77997519&loc=d3e13537-108611 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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