Segments and Geographic Area Analysis - Summary of Information about Disaggregated Revenue by Country (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting Information [Line Items]
Total revenues	$ 198,203	$ 216,706	$ 427,373	$ 450,248
Contract Drilling [Member]
Segment Reporting Information [Line Items]
Total revenues	188,637	207,273	406,503	433,970
Reimbursable Expenses [Member]
Segment Reporting Information [Line Items]
Total revenues	9,566	9,433	20,870	16,278
United States [Member]
Segment Reporting Information [Line Items]
Total revenues	85,438	119,026	193,481	259,604
United States [Member] | Contract Drilling [Member]
Segment Reporting Information [Line Items]
Total revenues	82,154	117,423	187,054	256,054
United States [Member] | Reimbursable Expenses [Member]
Segment Reporting Information [Line Items]
Total revenues	3,284	1,603	6,427	3,550
Brazil [Member]
Segment Reporting Information [Line Items]
Total revenues	56,982	29,116	120,108	82,430
Brazil [Member] | Contract Drilling [Member]
Segment Reporting Information [Line Items]
Total revenues	56,968	29,139	120,147	82,423
Brazil [Member] | Reimbursable Expenses [Member]
Segment Reporting Information [Line Items]
Total revenues	14	(23)	(39)	7
United Kingdom [Member]
Segment Reporting Information [Line Items]
Total revenues	30,806	42,343	66,650	68,858
United Kingdom [Member] | Contract Drilling [Member]
Segment Reporting Information [Line Items]
Total revenues	29,173	39,413	61,772	64,022
United Kingdom [Member] | Reimbursable Expenses [Member]
Segment Reporting Information [Line Items]
Total revenues	1,633	2,930	4,878	4,836
Australia [Member]
Segment Reporting Information [Line Items]
Total revenues	19,478	26,221	41,495	39,356
Australia [Member] | Contract Drilling [Member]
Segment Reporting Information [Line Items]
Total revenues	16,195	21,298	33,383	31,471
Australia [Member] | Reimbursable Expenses [Member]
Segment Reporting Information [Line Items]
Total revenues	3,283	$ 4,923	8,112	$ 7,885
Malaysia [Member]
Segment Reporting Information [Line Items]
Total revenues	5,499		5,639
Malaysia [Member] | Contract Drilling [Member]
Segment Reporting Information [Line Items]
Total revenues	4,147		4,147
Malaysia [Member] | Reimbursable Expenses [Member]
Segment Reporting Information [Line Items]
Total revenues	$ 1,352		$ 1,492