Amount of gain (loss) on sale or disposal of an equity method investment.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(b)(7)(c))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(b)(9)(a))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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- Definition

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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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.

+ References

No definition available.

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- Definition

The cash inflow associated with the deconsolidation of a previously consolidated subsidiary or sale of an entity that is related to it but not strictly controlled.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585

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- Definition

The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company before stock transaction.

+ References

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Dispositions and Other (additional information) (Details) - USD ($) $ in Millions		1 Months Ended	12 Months Ended
	Feb. 09, 2018	Jul. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale of Stock, Percentage of Ownership before Transaction			15.00%
Net gain on sale of business and investments			$ 49	$ 217	$ (6)
Hydro Facility Investment [Member]
Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Sale of Equity Method Investments		$ 12
Equity Method Investment, Realized Gain (Loss) on Disposal				7
Sanfeng Environmental [Member]
Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net gain on sale of business and investments				6
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] \| Pittsfield And Springfield EfW [Member]
Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net gain on sale of business and investments			$ (11)
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] \| Sanfeng Environmental [Member]
Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Divestiture of Interest in Subsidiaries and Affiliates	$ 13
Net gain on sale of business and investments				$ 6