Details of Selected Balance Sheet Accounts - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Concentration Risk [Line Items]
Increase (decrease) in contract with customer, asset	$ (2,900)
Contract with customer, asset, reclassified to receivable	18,700
Contract with customer, asset, increase due to revenue recognized	16,100
Increase (decrease) in contract with customer, liability	3,000
Contract with customer, liability, increase due to billings	10,500
Contract with customer, liability, revenue recognized	7,400
Impairments of inventories	25,230	$ 0
Impairment of fixed assets	5,198	0
Depreciation	20,100	24,800
Amortization	$ 6,300	$ 6,700
UNITED STATES \| Geographic Concentration Risk \| Accounts Receivable
Concentration Risk [Line Items]
Concentration risk, percentage	74.00%	73.00%
UNITED KINGDOM \| Geographic Concentration Risk \| Accounts Receivable
Concentration Risk [Line Items]
Concentration risk, percentage	10.00%		10.00%
Total Well Site Services [Member] \| Drilling Services
Concentration Risk [Line Items]
Impairments of inventories	$ 0
Impairment of fixed assets	$ 5,198

Contract with Customer, Asset, Increase Due to Revenue Recognized

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Contract with Customer, Liability, Increase Due to Billings

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The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of decrease in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time from transfer to receivable due to right to consideration becoming unconditional.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount of increase (decrease) in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

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