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The Company and Its Accounting Policies (Details) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2013 | Mar. 31, 2012
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Summary of costs and estimated earnings on contracts |  |
Costs incurred since inception on contracts in progress | $ 37,632 | $ 24,947
Estimated earnings since inception on contracts in progress | 12,311 | 12,108
Gross | 49,943 | 37,055
Less billings to date | 49,485 | 40,956
Net under billings | $ 458 | $ (3,901)

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