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Claims revenue (Tables)

12 Months Ended

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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