Drilling and Other Property and Equipment - Summary of Cost and Accumulated Depreciation of Drilling and Other Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property and equipment	$ 8,161,045	$ 8,366,400
Less: accumulated depreciation	(3,008,217)	(3,182,178)
Drilling and other property and equipment, net	5,152,828	5,184,222	$ 5,261,641
Drilling Rigs and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	8,004,489	8,210,824
Land and Buildings [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	64,267	63,757
Office Equipment and Other [Member]
Property, Plant and Equipment [Line Items]
Property and equipment	$ 92,289	$ 91,819