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Drilling and Other Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	2 Months Ended	3 Months Ended	4 Months Ended	6 Months Ended
	Apr. 23, 2021	Jun. 30, 2021	Jun. 30, 2020	Apr. 23, 2021	Jun. 30, 2020
Property, Plant and Equipment [Line Items]
Impairment charge of assets				$ 197,027	$ 774,028
Gain (loss) on disposition of assets	$ 85	$ 176	$ 220	5,486	$ 3,653
Ocean Valor [Member]
Property, Plant and Equipment [Line Items]
Net book value of assets		$ 1,000
Ocean America and Ocean Rover [Member]
Property, Plant and Equipment [Line Items]
Gain (loss) on disposition of assets				$ 4,400