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No definition available.

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- Definition

Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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- Definition

This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity 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 subject to the equity accounting method. 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 323
-SubTopic 10
-Section 35
-Paragraph 32
-URI http://asc.fasb.org/extlink&oid=118954474&loc=d3e32787-111569

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
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- Definition

Amount of distribution received from equity method investee for return of investment, classified as investing activities. Excludes distribution for return on investment, classified as operating activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 21D
-URI http://asc.fasb.org/extlink&oid=118932676&loc=SL94080555-108585

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- Definition

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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Investments in Unconsolidated Affiliates (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Sep. 06, 2019	Sep. 05, 2019	Dec. 31, 2016
Investments In Unconsolidated Affiliates [Line Items]
Distributions from equity investments	$ 55	$ 108	$ 13
Distributions from equity investments, return of capital	$ 11	137	$ 281
Constitution \| VIE, Not Primary Beneficiary
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest	24.00%
ACP
Investments In Unconsolidated Affiliates [Line Items]
Distributions from equity investments, return of capital	$ 265
Electric Utilities and Infrastructure \| DATC
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest	50.00%
Electric Utilities and Infrastructure \| Pioneer
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest	50.00%
Commercial Renewables \| DS Cornerstone
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest				26.00%	50.00%
Gas Utilities and Infrastructure \| Constitution \| VIE, Not Primary Beneficiary
Investments In Unconsolidated Affiliates [Line Items]
OTTI impairment loss	$ 25	55
Gas Utilities and Infrastructure \| ACP
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest	47.00%
Gas Utilities and Infrastructure \| Constitution
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest	24.00%
Gas Utilities and Infrastructure \| Constitution \| Constitution \| VIE, Not Primary Beneficiary
Investments In Unconsolidated Affiliates [Line Items]
OTTI impairment loss	$ 25
Other \| NMC
Investments In Unconsolidated Affiliates [Line Items]
Ownership interest	17.50%		17.50%			25.00%
Board representation and voting rights, ownership percentage	25.00%
Piedmont
Investments In Unconsolidated Affiliates [Line Items]
Distributions from equity investments	$ 1	1	$ 4
Distributions from equity investments, return of capital	$ 4	$ 3	$ 2