Long-Lived Asset Impairments (Notes)	12 Months Ended
Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Long-lived and Other Asset Impairments	Long-Lived Asset Impairments In the fourth quarter of 2017, we recognized long-lived asset impairments of $928 million, of which $923 million was related to PP&E impairments and $5 million was related to the impairment of intangible assets. The PP&E impairments in our Eastern Hemisphere segment include a $740 million write-down to the lower of carrying amount or fair value less cost to sell of our land drilling rigs classified as held for sale, $135 million related to Western Hemisphere segment product line assets and $37 million related to other Eastern Hemisphere segment product line assets. In addition, we recognized $11 million of long-lived impairment charges related to Corporate assets. The 2017 impairments were due to the sustained downturn in the oil and gas industry, whose recovery was not as strong as expected and whose recovery in subsequent quarters was slower than had previously been anticipated. The change in the expectations of the market’s recovery, in addition to successive negative operating cash flows in certain asset groups represented an indicator that those assets will no longer be recoverable over their remaining useful lives. See “Note 14 – Fair Value of Financial Instruments, Assets and Equity Investments” for additional information regarding the fair value determination used in the impairment calculation. During 2016, we recognized long-lived asset impairment charges of $436 million, of which $388 million was related to PP&E impairments and $48 million was related to the impairment of intangible assets. The PP&E impairment charges by segment were $251 million in the Western Hemisphere related to our Well Construction, Drilling Services and Managed Pressure Drilling assets and $137 million in the Eastern Hemisphere related to our Eastern Hemisphere Pressure Pumping assets. The intangible asset charge is related to the Well Construction and Completions businesses with $35 million attributable to the Western Hemisphere segment and $13 million related the Eastern Hemisphere segment. The impairments in 2016 were due to the prolonged downturn in the oil and gas industry, whose recovery was not as strong as expected and whose recovery in subsequent quarters was slower than had previously been anticipated. The change in the expectations of the market’s recovery, in addition to successive negative operating cash flows in certain asset groups represented an indicator that those assets will no longer be recoverable over their remaining useful lives. See “Note 14 – Fair Value of Financial Instruments, Assets and Equity Investments” for additional information regarding the fair value determination used in the impairment calculation. During 2015, we recognized long-lived asset impairment charges of $638 million, of which $124 million was related to Pressure Pumping assets in the Western Hemisphere, $259 million for equipment in our Pressure Pumping, Drilling Tools, and Wireline assets in the Western Hemisphere and $255 million related to our land drilling rigs product line assets in the Eastern Hemisphere. The impairments in 2015 were due to the continued weakness in crude oil prices contributing to lower exploration and production spending and a decline in the utilization of our assets. The decline in oil prices and its impact on demand represented a significant adverse change in the business climate and an indication that these long-lived assets may not be recoverable. Based on the presence of impairment indicators, we performed an analysis of these asset groups and recorded long-lived asset impairment charges to adjust the assets to fair value. The fair value of our drilling tools, pressure pumping, and wireline assets were estimated using a combination of the income approach, the cost approach, and the market approach. See “Note 14 – Fair Value of Financial Instruments, Assets and Equity Investments” for additional information regarding the fair value determination.

Long-Lived Asset Impairments

In the fourth quarter of 2017, we recognized long-lived asset impairments of $928 million, of which $923 million was related to PP&E impairments and $5 million was related to the impairment of intangible assets. The PP&E impairments in our Eastern Hemisphere segment include a $740 million write-down to the lower of carrying amount or fair value less cost to sell of our land drilling rigs classified as held for sale, $135 million related to Western Hemisphere segment product line assets and $37 million related to other Eastern Hemisphere segment product line assets. In addition, we recognized $11 million of long-lived impairment charges related to Corporate assets. The 2017 impairments were due to the sustained downturn in the oil and gas industry, whose recovery was not as strong as expected and whose recovery in subsequent quarters was slower than had previously been anticipated. The change in the expectations of the market’s recovery, in addition to successive negative operating cash flows in certain asset groups represented an indicator that those assets will no longer be recoverable over their remaining useful lives. See “Note 14 – Fair Value of Financial Instruments, Assets and Equity Investments” for additional information regarding the fair value determination used in the impairment calculation.

During 2016, we recognized long-lived asset impairment charges of $436 million, of which $388 million was related to PP&E impairments and $48 million was related to the impairment of intangible assets. The PP&E impairment charges by segment were $251 million in the Western Hemisphere related to our Well Construction, Drilling Services and Managed Pressure Drilling assets and $137 million in the Eastern Hemisphere related to our Eastern Hemisphere Pressure Pumping assets. The intangible asset charge is related to the Well Construction and Completions businesses with $35 million attributable to the Western Hemisphere segment and $13 million related the Eastern Hemisphere segment.

The impairments in 2016 were due to the prolonged downturn in the oil and gas industry, whose recovery was not as strong as expected and whose recovery in subsequent quarters was slower than had previously been anticipated. The change in the expectations of the market’s recovery, in addition to successive negative operating cash flows in certain asset groups represented an indicator that those assets will no longer be recoverable over their remaining useful lives. See “Note 14 – Fair Value of Financial Instruments, Assets and Equity Investments” for additional information regarding the fair value determination used in the impairment calculation.

During 2015, we recognized long-lived asset impairment charges of $638 million, of which $124 million was related to Pressure Pumping assets in the Western Hemisphere, $259 million for equipment in our Pressure Pumping, Drilling Tools, and Wireline assets in the Western Hemisphere and $255 million related to our land drilling rigs product line assets in the Eastern Hemisphere. The impairments in 2015 were due to the continued weakness in crude oil prices contributing to lower exploration and production spending and a decline in the utilization of our assets. The decline in oil prices and its impact on demand represented a significant adverse change in the business climate and an indication that these long-lived assets may not be recoverable. Based on the presence of impairment indicators, we performed an analysis of these asset groups and recorded long-lived asset impairment charges to adjust the assets to fair value.

The fair value of our drilling tools, pressure pumping, and wireline assets were estimated using a combination of the income approach, the cost approach, and the market approach. See “Note 14 – Fair Value of Financial Instruments, Assets and Equity Investments” for additional information regarding the fair value determination.