Long-Lived Asset Impairments (Notes)	12 Months Ended
Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Long-lived and Other Asset Impairments	9. Long-Lived Asset Impairments During 2018, we recognized long-lived asset impairments of $151 million, of which $141 million ($43 million in our Western Hemisphere segment and $98 million in our Eastern Hemisphere segment) was to write-down our land drilling rigs assets to the lower of carrying amount or fair value less cost to sell and the remaining $10 million ($3 million was in our Western Hemisphere and $7 million is in our Eastern Hemisphere segment) of charges were for land drilling rigs assets charges not in held for sale. See “Note 4 – Business Combinations and Divestitures” for more details. The 2018 impairments were due to the sustained downturn in the oil and gas industry that resulted a reassessment of our disposal groups for our land drilling rigs. The change in our expectations of the market’s recovery, in addition to successive negative operating cash flows in certain disposal asset groups represented an indicator that those assets will no longer be recoverable over their remaining useful lives. See “Note 13 – Fair Value of Financial Instruments, Assets and Other Assets” for additional information regarding the fair value determination used in the impairment calculation. During 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 13 – Fair Value of Financial Instruments, Assets and Other Assets” 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 2016 impairments 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 in 2016 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 13 – Fair Value of Financial Instruments, Assets and Other Assets” for additional information regarding the fair value determination used in the impairment calculation.

9. Long-Lived Asset Impairments

During 2018, we recognized long-lived asset impairments of $151 million, of which $141 million ($43 million in our Western Hemisphere segment and $98 million in our Eastern Hemisphere segment) was to write-down our land drilling rigs assets to the lower of carrying amount or fair value less cost to sell and the remaining $10 million ($3 million was in our Western Hemisphere and $7 million is in our Eastern Hemisphere segment) of charges were for land drilling rigs assets charges not in held for sale. See “Note 4 – Business Combinations and Divestitures” for more details. The 2018 impairments were due to the sustained downturn in the oil and gas industry that resulted a reassessment of our disposal groups for our land drilling rigs. The change in our expectations of the market’s recovery, in addition to successive negative operating cash flows in certain disposal asset groups represented an indicator that those assets will no longer be recoverable over their remaining useful lives. See “Note 13 – Fair Value of Financial Instruments, Assets and Other Assets” for additional information regarding the fair value determination used in the impairment calculation.

During 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 13 – Fair Value of Financial Instruments, Assets and Other Assets” 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 2016 impairments 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 in 2016 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 13 – Fair Value of Financial Instruments, Assets and Other Assets” for additional information regarding the fair value determination used in the impairment calculation.