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Claims revenue (Tables) | 12 Months Ended
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Mar. 31, 2013
Contractors [Abstract] |
Schedule of claims revenue | Claims revenue
Year ended March 31, |  | 2013 |  |  | 2012 |  |  | 2011 |
Claims revenue recognized |  | $ | 20,994 |  |  | $ | 32,612 |  |  | $ | 2,521 |
Claims revenue uncollected (classified as unbilled revenue) |  | 18,426 |  |  | 22,393 |  |  | 1,742 |

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- Definition Schedule of Contract Claims Revenue [Table Text Block] + References No definition available. + Details
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- Details
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