Revenue Recognition - Schedule of Revenue by Customers (Details) - Customer concentration risk - Revenue	3 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Wind \| Inox Wind Limited
Revenue, Major Customer [Line Items]
Concentration risk, revenue	25.00%	22.00%
Grid \| Vestas WTG Mexico
Revenue, Major Customer [Line Items]
Concentration risk, revenue	36.00%	0.00%
Grid \| U.S. Navy
Revenue, Major Customer [Line Items]
Concentration risk, revenue		35.00%

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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