Revenue (Policies)	12 Months Ended
Dec. 31, 2020
Revenue [Abstract]
Revenue recognition	Revenue recognitionOur services and products are generally sold based upon purchase orders or contracts with our customers that include fixed or determinable prices but do not include right of return provisions or other significant post-delivery obligations. The vast majority of our service and product contracts are short-term in nature. We recognize revenue based on the transfer of control or our customers' ability to benefit from our services and products in an amount that reflects the consideration we expect to receive in exchange for those services and products. We also assess our customers' ability and intention to pay, which is based on a variety of factors, including our historical payment experience with, and the financial condition of our customers. Rates for services are typically priced on a per day, per meter, per man-hour, or similar basis.Revenue is recognized based on the transfer of control or our customers' ability to benefit from our services and products in an amount that reflects the consideration we expect to receive in exchange for those services and products. The vast majority of our service and product contracts are short-term in nature. In recognizing revenue for our services and products, we determine the transaction price of purchase orders or contracts with our customers, which may consist of fixed and variable consideration. We also assess our customers' ability and intention to pay, which is based on a variety of factors, including our historical payment experience with, and the financial condition of our customers. Payment terms and conditions vary by contract type, although terms generally include a requirement of payment within 20 to 60 days. Other judgments involved in recognizing revenue include an assessment of progress towards completion of performance obligations for certain long-term contracts, which involve estimating total costs to determine our progress towards contract completion, and calculating the corresponding amount of revenue to recognize.

Revenue (Policies)

12 Months Ended

Dec. 31, 2020

Revenue recognitionOur services and products are generally sold based upon purchase orders or contracts with our customers that include fixed or determinable prices but do not include right of return provisions or other significant post-delivery obligations. The vast majority of our service and product contracts are short-term in nature. We recognize revenue based on the transfer of control or our customers' ability to benefit from our services and products in an amount that reflects the consideration we expect to receive in exchange for those services and products. We also assess our customers' ability and intention to pay, which is based on a variety of factors, including our historical payment experience with, and the financial condition of our customers. Rates for services are typically priced on a per day, per meter, per man-hour, or similar basis.Revenue is recognized based on the transfer of control or our customers' ability to benefit from our services and products in an amount that reflects the consideration we expect to receive in exchange for those services and products. The vast majority of our service and product contracts are short-term in nature. In recognizing revenue for our services and products, we determine the transaction price of purchase orders or contracts with our customers, which may consist of fixed and variable consideration. We also assess our customers' ability and intention to pay, which is based on a variety of factors, including our historical payment experience with, and the financial condition of our customers. Payment terms and conditions vary by contract type, although terms generally include a requirement of payment within 20 to 60 days. Other judgments involved in recognizing revenue include an assessment of progress towards completion of performance obligations for certain long-term contracts, which involve estimating total costs to determine our progress towards contract completion, and calculating the corresponding amount of revenue to recognize.