Restructuring Charges Incurred by Segment and Cost Type (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Sep. 30, 2015	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Restructuring Cost And Reserve [Line Items]
Restructuring charges	$ 7,600	$ 4,100	$ 7,586	$ 4,052
Americas | Crew Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges			3,410
Americas | Other Vessel Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges			203
Asia/Pacific | Crew Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges			$ 3,973	3,697
Corporate | General and Administrative Expenses
Restructuring Cost And Reserve [Line Items]
Restructuring charges				$ 355