Property and Equipment - Property and Equipment, at Cost (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	$ 14,056,323	$ 14,442,922
Drilling Equipment and Facilities [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	13,074,804	13,254,240
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	761,347	969,985
Other [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, at cost	$ 220,172	$ 218,697