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Subsequent Events - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended			1 Months Ended	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2014 Deepwater PSVs Vessel	Mar. 31, 2014 Subsequent Event	May 21, 2014 Subsequent Event May 2014 Authorized Amount	Mar. 31, 2014 Subsequent Event Sonatide joint venture	Mar. 31, 2014 Subsequent Event Deepwater PSVs Vessel	Mar. 31, 2014 Subsequent Event PSV Vessel	Mar. 31, 2014 Subsequent Event PSV Minimum	Mar. 31, 2014 Subsequent Event PSV Maximum
Subsequent Event [Line Items]
Significant commitment, new construction amount committed			$ 134
Number of vessels under construction		23				1	2
Significant commitment, new construction final delivery date	June 2016					April 2016		January 2015	April 2015
Proceeds from related party					66
Equivalent revenue days for the cash collected from affliate					62 days
Amount authorized to repurchase shares				$ 200.0