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Drilling and Other Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		4 Months Ended	5 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Apr. 23, 2021	Sep. 30, 2021	Sep. 30, 2020
Property, Plant and Equipment [Line Items]
Impairment charge of assets			$ 197,027		$ 774,028
Gain (loss) on disposition of assets	$ 767	$ 479	5,486	$ 943	$ 4,132
Ocean Valor [Member]
Property, Plant and Equipment [Line Items]
Net book value of assets	$ 1,000			$ 1,000
Ocean America and Ocean Rover [Member]
Property, Plant and Equipment [Line Items]
Gain (loss) on disposition of assets			$ 4,400