Amount of expense (reversal of expense) which increases (decreases) the accrual for environmental loss contingencies from revisions in estimates to existing obligations. Excludes changes related to business acquisitions, divestitures, or currency movement.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the cost method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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Amount of gain (loss) on sale or disposal of proven and unproven oil and gas properties.

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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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The aggregate amount of asset impairment charges, (gains) and losses related to the divestiture of businesses and unusual items incurred during an accounting period.

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Asset Impairments and Unusual Items - Details (Details) - USD ($) $ in Millions	3 Months Ended						12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
(Gain) loss from divestitures, asset impairments and unusual items, net							$ (58)	$ (16)	$ 112
Gain (loss) on sale of assets			$ 40				96	38	(9)
Asset impairments	$ 8						38	41	59
Goodwill impairment charges				$ 34			6	34	12
San Jacinto Waste Pits [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Revisions in estimate					$ 9			11	44
Lamp Tracker Reporting Unit [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Goodwill impairment charges	6
Oil and Gas Well [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Gains from sale of oil and gas properties				31				31
Energy and Environmental Services [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Decrease in contingent consideration				(30)				(30)
Renewable Energy Assets [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Asset impairments								7
Investment In Majority Owned Organics Company [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Gain (loss) on sale of assets									(8)
Waste Diversion Technology Company [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Equity method investments impairment charges						$ 25		29
Cost method investment impairment				$ 11				11	42
Landfill [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Asset impairments		$ 29					30		$ 43
Tier 1 [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Gain (loss) on sale of assets	$ 52						52
Other [Member]
Income Expense From Divestitures Asset Impairments And Unusual Items [Line Items]
Gain (loss) on sale of assets							44
Goodwill impairment charges							$ 6	$ 34