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v3.19.3.a.u2

Note 2 - Revenue Recognition - Revenues By Major Customers (Details) - Customer Concentration Risk [Member] - Revenue Benchmark [Member] | 3 Months Ended | 9 Months Ended
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018
Wind [Member] | Inox Wind Limited [Member] |  |  |  |
Concentration risk percentage | 10.00% | 47.00% | 11.00% | 40.00%
Grid [Member] | Department of Homeland Security [Member] |  |  |  |
Concentration risk percentage | 22.00% | 10.00% | 12.00% | 10.00%
Grid [Member] | Vestas WTG Mexico [Member] |  |  |  |
Concentration risk percentage | 25.00% | 10.00% | 10.00% | 15.00%
Grid [Member] | Fuji Bridex Pte Ltd [Member] |  |  |  |
Concentration risk percentage | 10.00% | 17.00% | 10.00% | 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13531-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13537-108611 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592 + Details
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