Commitments and Contingencies - Additional Information (Detail) $ in Thousands		3 Months Ended
		Jun. 30, 2017 USD ($) Vessel T	Mar. 31, 2017 USD ($)
Significant Purchase and Supply Commitment [Line Items]
Accumulated costs of rejected vessel	[1]	$ 48,666	$ 48,382
Fast, Crew/Supply Boat
Significant Purchase and Supply Commitment [Line Items]
Number of vessels under construction | Vessel		1
Insurance coverage for the progress payments made on the vessel by the third party credit support		90.00%
Insurance coverage by the third party credit support for the carrying value of the accumulated costs		$ 2,400
Impairment charge on amounts not recoverable		2,400
Fast, Crew/Supply Boat | Reclassification of Construction in Progress to Other Non-Current Assets
Significant Purchase and Supply Commitment [Line Items]
Committed and invested amount, remaining		5,600
Deepwater PSV
Significant Purchase and Supply Commitment [Line Items]
Remaining Balance, commitments		$ 6,200
Number of Vessels, commitments | Vessel		1
Significant commitment, new construction deadweight tons capacity | T		5,400
Final contractual milestone payment withheld			4,500
Refund amount demanded to shipyard			43,000
Accumulated costs of rejected vessel			$ 48,700
Number of vessels under construction | Vessel	[2]	1

[1] Refer to Note (10) of Notes to Condensed Consolidated Financial Statements for additional information regarding the vessel rejected at the time of delivery.

[2] Two remaining option vessels, a vessel rejected at the time of delivery and a fast supply boat are not included in the table above.