General Information - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Apr. 23, 2021	Dec. 31, 2020
Restricted Cash And Cash Equivalents Items [Line Items]
Restricted cash	$ 24,266	$ 35,447	$ 24,511
Restricted cash, nature of restriction, description	We maintain restricted cash bank accounts, of which $24.2 million is subject to restrictions pursuant to a management and marketing services agreement with an offshore drilling company and $0.1 million is subject to restrictions pursuant to a court order, to settle certain professional fees incurred upon or prior to our emergence from bankruptcy.
Management and Marketing Services Agreement [Member]
Restricted Cash And Cash Equivalents Items [Line Items]
Restricted cash	$ 24,200
Professional Fees [Member]
Restricted Cash And Cash Equivalents Items [Line Items]
Restricted cash	$ 100