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Goodwill and Intangible Assets - Additional Information (Detail) - USD ($)
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Goodwill And Intangible Assets Disclosure [Line Items]    
Goodwill $ 0  
Goodwill impairment charge   $ 395,060,000
Amortization expense on intangible assets $ 3,100,000 5,300,000
Contract Drilling    
Goodwill And Intangible Assets Disclosure [Line Items]    
Goodwill impairment charge   $ 395,000,000