Risk Management and Fair Values (Derivative Instruments Designated as Cash Flow Hedges On Consolidated Statements Of Income) (Details) $ in Millions	9 Months Ended
Sep. 30, 2021 USD ($)
Effect of Derivative instruments designated as cash flow hedges on consolidated statements of income
Derivative Instruments Gain Loss Reclassified From Accumulated O C I Into Income Effective Portion Tax	$ 8
Competitive Businesses Operating Revenues [Member] \| Electricity Swaps And Options [Member] \| Cash Flow Hedging [Member]
Effect of Derivative instruments designated as cash flow hedges on consolidated statements of income
Amount of gain reclassified from accumulated OCI into income (effective portion)	40
Unrealized Gain (Loss) on Derivatives	$ 2

Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion, Tax.

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- Definition

Effect of Derivative instruments designated as cash flow hedges on consolidated statements of income.

+ References

No definition available.

+ Details

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624177-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

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