Goodwill and Intangible Assets - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Goodwill And Intangible Assets Disclosure [Line Items]
Increase in goodwill		$ 2,100,000
Goodwill impairment charge	$ 395,060,000	17,800,000	$ 211,129,000
Cost incurred to renew or extend term of intangible asset			0
Impairment on intangible assets	0	0	0
Amortization expense on intangible assets	19,300,000	$ 17,900,000	$ 18,300,000
Contract Drilling
Goodwill And Intangible Assets Disclosure [Line Items]
Percentage fair value exceeds carrying values		13.00%	16.00%
Goodwill impairment charge	$ 395,060,000	$ 0	$ 0
Oilfield Rentals and Electrical Controls and Automation Reporting Unit
Goodwill And Intangible Assets Disclosure [Line Items]
Goodwill impairment charge		$ 17,800,000
Oilfield Rental
Goodwill And Intangible Assets Disclosure [Line Items]
Percentage fair value exceeds carrying values			14.00%
Goodwill impairment charge			$ 0
Pressure Pumping and Directional Drilling
Goodwill And Intangible Assets Disclosure [Line Items]
Goodwill impairment charge			$ 211,000,000

Cost incurred for term of intangible assets.

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Goodwill and intangible assets disclosure.

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Percentage fair value exceeds carrying value.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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