Segments and Geographic Area Analysis - Long-Lived Tangible Assets by Country (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Drilling and other property and equipment, net	$ 5,152,828	$ 5,184,222	$ 5,261,641
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Drilling and other property and equipment, net	2,227,934	2,245,989	2,300,956
United Kingdom [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Drilling and other property and equipment, net	1,061,585	1,083,540	133,525
Brazil [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Drilling and other property and equipment, net	883,607	923,355	923,398
Australia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Drilling and other property and equipment, net	570,964	242,929	629,436
Singapore [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Drilling and other property and equipment, net	404,420	366,798	17
Malaysia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Drilling and other property and equipment, net	2,037	318,191	1,084,793
Other Countries [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Drilling and other property and equipment, net	2,281	3,420	189,516
International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Drilling and other property and equipment, net	$ 2,924,894	$ 2,938,233	$ 2,960,685