Segments and Geographic Area Analysis - Summary of Information about Disaggregated Revenue by Equipment-type and Country (Detail) - USD ($) $ in Thousands	4 Months Ended	8 Months Ended	12 Months Ended
	Apr. 23, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Total revenues	$ 169,379	$ 556,066	$ 733,687	$ 980,644
Contract Drilling [Member]
Segment Reporting Information [Line Items]
Total revenues	153,364	465,328	692,753	934,934
Reimbursable Expenses [Member]
Segment Reporting Information [Line Items]
Total revenues	16,015	90,738	40,934	45,710
United States [Member]
Segment Reporting Information [Line Items]
Total revenues	100,263	250,383	334,412	515,640
United States [Member] | Contract Drilling [Member]
Segment Reporting Information [Line Items]
Total revenues	93,215	194,912	321,150	507,759
United States [Member] | Reimbursable Expenses [Member]
Segment Reporting Information [Line Items]
Total revenues	7,048	55,471	13,262	7,881
Australia [Member]
Segment Reporting Information [Line Items]
Total revenues	21,728	110,733	77,147	109,642
Australia [Member] | Contract Drilling [Member]
Segment Reporting Information [Line Items]
Total revenues	17,031	95,601	63,876	85,932
Australia [Member] | Reimbursable Expenses [Member]
Segment Reporting Information [Line Items]
Total revenues	4,697	15,132	13,271	23,710
United Kingdom [Member]
Segment Reporting Information [Line Items]
Total revenues	30,267	59,104	121,050	163,760
United Kingdom [Member] | Contract Drilling [Member]
Segment Reporting Information [Line Items]
Total revenues	27,967	55,245	112,121	149,724
United Kingdom [Member] | Reimbursable Expenses [Member]
Segment Reporting Information [Line Items]
Total revenues	2,300	3,859	8,929	14,036
Senegal [Member]
Segment Reporting Information [Line Items]
Total revenues		58,868
Senegal [Member] | Contract Drilling [Member]
Segment Reporting Information [Line Items]
Total revenues		48,758
Senegal [Member] | Reimbursable Expenses [Member]
Segment Reporting Information [Line Items]
Total revenues		10,110
Brazil [Member]
Segment Reporting Information [Line Items]
Total revenues	3,421	42,215	155,418	191,602
Brazil [Member] | Contract Drilling [Member]
Segment Reporting Information [Line Items]
Total revenues	3,421	42,215	155,436	191,519
Brazil [Member] | Reimbursable Expenses [Member]
Segment Reporting Information [Line Items]
Total revenues			(18)	$ 83
Myanmar [Member]
Segment Reporting Information [Line Items]
Total revenues	13,700	34,763
Myanmar [Member] | Contract Drilling [Member]
Segment Reporting Information [Line Items]
Total revenues	11,730	28,597
Myanmar [Member] | Reimbursable Expenses [Member]
Segment Reporting Information [Line Items]
Total revenues	$ 1,970	$ 6,166
Malaysia [Member]
Segment Reporting Information [Line Items]
Total revenues			45,660
Malaysia [Member] | Contract Drilling [Member]
Segment Reporting Information [Line Items]
Total revenues			40,170
Malaysia [Member] | Reimbursable Expenses [Member]
Segment Reporting Information [Line Items]
Total revenues			$ 5,490