Asset Purchase Agreement, Additional Percentage Share of Cost of Control

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- Definition

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

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- Definition

Clean Power Plan, Optional Extension Period

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- Definition

Environmental Matters [Abstract]

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- Definition

Guarantor Obligations, Number of Parental Guarantees

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- Definition

Industry Litigation, Period to Complete Rulemaking Proceeding

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- Definition

Represent information pertaining to share of the assessment.

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- Definition

Represent information pertaining to total amount of coal severance surtax, penalty, and interest related to coal supplied under the coal supply agreement.

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- Definition

Loss Contingency, Partial Payment of Assessment

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- Definition

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

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No definition available.

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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=65885119&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.

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Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

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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)					9 Months Ended	12 Months Ended
	Jul. 06, 2016 guarantee	Jun. 24, 2016	Mar. 16, 2016 USD ($)	May 23, 2013 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2016 USD ($)
Environmental Matters [Abstract]
Clean power plan, optional extension period						2 years
Payment Guarantee
Financial Assurances
Number of parental guarantees \| guarantee	2
Four Corners \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Additional expected environment cost						$ 15,000,000
Cholla Units 1-3 \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Expected environmental cost						8,000,000
New Mexico Tax Matter \| Four Corners
Environmental Matters [Abstract]
Coal severance surtax, penalty, and interest				$ 30,000,000
Litigation settlement, amount			$ 1,000,000
New Mexico Tax Matter \| Four Corners \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Share of the assessment				12,000,000
Partial payment assessment				$ 800,000
Litigation settlement, amount			$ 800,000
Letter of credit \| ARIZONA PUBLIC SERVICE COMPANY
Financial Assurances
Outstanding letters of credit						35,000,000
Equity Lessors Sale Leaseback Letter of Credit \| ARIZONA PUBLIC SERVICE COMPANY
Financial Assurances
Outstanding letters of credit						53,000,000
Four Corners Units 4 and 5 \| Four Corners \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Additional expected environment cost						45,000,000
Four Corners Units 4 and 5 \| Navajo Plant \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Expected environmental cost						$ 200,000,000
Four Corners Units 4 and 5 \| Natural Gas Tolling Letter of Credit \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Percentage share cost of control						63.00%
Additional percentage share of cost of control						7.00%
Minimum \| Four Corners Units 4 and 5 \| Four Corners \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Expected environmental cost						$ 400,000,000
Regional Haze Rules \| Cholla \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Expected environmental cost					$ 100,000,000
Mercury and Air Toxic Standards \| Navajo Generating Station \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Expected environmental cost						1,000,000
Coal Combustion Waste \| Navajo Generating Station \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Additional expected environment cost						1,000,000
Coal Combustion Waste \| Boron Inclusion on List of Groundwater Constituents \| Navajo Generating Station \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Period to complete rulemaking proceeding		3 years
Coal Combustion Waste \| Minimum \| Cholla \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Additional expected environment cost						5,000,000
Coal Combustion Waste \| Maximum \| Cholla \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Additional expected environment cost						$ 40,000,000
El Paso's Interest in Four Corners \| 4CA
Financial Assurances
Ownership interest acquired	7.00%					7.00%