Asset Purchase Agreement, Additional Percentage Share of Cost of Control

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- Definition

Asset Purchase Agreement, Operating and Maintenance Cost Reimbursement Receivable

+ References

No definition available.

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- Definition

Asset Purchase Agreement, Option to Purchase, Ownership Interest, Percentage

+ References

No definition available.

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- Definition

Asset Purchase Agreement, Proceeds from Operating an Maintenance Cost Reimbursement

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- Definition

Asset Purchase Agreement, Site Contingency, Increase in Loss Exposure Not Accrued, Best Estimate

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- Definition

Environmental Matters [Abstract]

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- References

No definition available.

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- Definition

Guarantor Obligations, Number of Parental Guarantees

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- Definition

Represents the percentage of share of the cost of control acquired by the entity.

+ References

No definition available.

+ Details

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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-Name Accounting Standards Codification
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- Definition

Best estimate of the loss exposure for reasonably possible environmental contingencies at an individual site for which no accrual has been recorded.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 10
-Subparagraph (c),(d)(2)
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13237-110859

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Commitments and Contingencies Commitments and Contingencies - Environmental Matters and Financial Assurances (Details) $ in Millions			12 Months Ended
	Jun. 13, 2017 USD ($)	Jul. 06, 2016 guarantee	Dec. 31, 2017 USD ($)
Payment Guarantee
Financial Assurances
Number of parental guarantees \| guarantee		4
Letter of credit \| ARIZONA PUBLIC SERVICE COMPANY
Financial Assurances
Outstanding letters of credit			$ 5
Equity Lessors Sale Leaseback Letter of Credit \| ARIZONA PUBLIC SERVICE COMPANY
Financial Assurances
Outstanding letters of credit			62
Four Corners \| NTEC
Environmental Matters [Abstract]
Option to purchase, ownership interest (as a percent)		7.00%
Four Corners \| 4CA
Environmental Matters [Abstract]
Percentage share cost of control		7.00%
Four Corners \| Coal Supply Agreement Arbitration
Environmental Matters [Abstract]
Damages sought	$ 30
Four Corners \| Coal Supply Agreement Arbitration \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Damages sought	$ 17
Four Corners \| Coal Supply Agreement Arbitration \| NTEC
Environmental Matters [Abstract]
Option to purchase, ownership interest (as a percent)		7.00%
Four Corners \| Coal Supply Agreement Arbitration \| 4CA
Environmental Matters [Abstract]
Payment received for coal supply agreement			10
Operating and maintenance cost reimbursement receivable			20
Regional Haze Rules \| Navajo Generating Station \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Expected environmental cost			$ 200
Regional Haze Rules \| Four Corners Units 4 and 5 \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Percentage share cost of control			63.00%
Expected environmental cost			$ 400
Regional Haze Rules \| Four Corners Units 4 and 5 \| Four Corners \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Additional expected environment cost			$ 45
Regional Haze Rules \| Four Corners Units 4 and 5 \| Natural Gas Tolling Letter of Credit \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Additional percentage share of cost of control			7.00%
Coal Combustion Waste \| Four Corners \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Additional expected environment cost			$ 22
Coal Combustion Waste \| Navajo Generating Station \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Additional expected environment cost			1
Coal Combustion Waste \| Minimum \| Cholla \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Additional expected environment cost			$ 20
El Paso's Interest in Four Corners \| 4CA
Financial Assurances
Ownership interest acquired (as a percent)		7.00%	7.00%