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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands | 1 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2016 | Dec. 31, 2015 | Mar. 31, 2016 | Mar. 31, 2015 | Mar. 31, 2014
Inventory reserve | $ 2,700 |  | $ 2,700 | $ 1,400 |
Benefit to cost of revenues |  |  | 5,000 | 8,000 | $ 4,300
Impairment of minority interest investments |  |  | 746 | 3,464 | 1,265
Payments received from customers |  |  | $ 0 | $ 0 | $ 3,700
Guaranteed annual payments, description |  |  | BASF has also agreed to make guaranteed annual payments to the Company through 2017 and has an option to continue the joint development through 2018. |  |
Minimum percentage of amount being realized upon ultimate settlement |  |  | 50.00% |  |
Repatriated amount |  |  | $ 1,200 |  |
Common equivalent shares not included in the calculation of diluted EPS |  |  | 1,552,959 | 1,567,352 | 643,158
Net foreign currency transaction and hedging gains (losses) |  |  | $ (2,300) | $ 2,800 | $ (100)
Foreign Earnings Repatriated |  |  |  |  |
Federal and state deferred tax liability | 400 |  | 400 |  |
Tres Amigas |  |  |  |  |
Impairment of minority interest investments |  |  | $ 700 |  |
Blade Dynamics Ltd |  |  |  |  |
Impairment of minority interest investments |  |  |  | $ 3,500 | $ 1,300
Maximum |  |  |  |  |
Warranty period |  |  | 3 years |  |
Minimum |  |  |  |  |
Warranty period |  |  | 1 year |  |
Inox Wind Limited |  |  |  |  |
Strategic agreements value |  | $ 210,000 |  |  |
Inox Wind Limited | Maximum |  |  |  |  |
Period allowable to manufacture the electrical control system |  |  | 4 years |  |
Inox Wind Limited | Minimum |  |  |  |  |
Period allowable to manufacture the electrical control system |  |  | 3 years |  |
BASF Corporation |  |  |  |  |
License revenue | $ 3,000 |  |  |  |
Credit Concentration Risk | Accounts Receivable | Inox Wind Limited | Maximum |  |  |  |  |
Risk percentage |  |  | 84.00% | 56.00% |
Credit Concentration Risk | Accounts Receivable | Inox Wind Limited | Minimum |  |  |  |  |
Risk percentage |  |  | 10.00% | 10.00% |

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