Schedule of Other Liabilities and Deferred Credits (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Mar. 31, 2015
Other Current Assets, Other Assets Accrued Expenses Other Current Liabilities and other Non current liabilities and Deferred Credits [Abstract]
Postretirement benefits liability	$ 20,651	$ 23,018
Pension liabilities	42,773	41,279
Deferred gain on vessel sales	118,420	136,238
Other	28,395	34,573
Other liabilities and deferred credits	$ 210,239	$ 235,108