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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- References

No definition available.

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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.

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

Surety Bonds Expiring, Amount

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

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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.

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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 - Environmental Matters and Financial Assurances (Details) $ in Millions					9 Months Ended
	Jul. 06, 2016 guarantee	Jun. 24, 2016	Mar. 16, 2016 USD ($)	May 23, 2013 USD ($)	Sep. 30, 2016 USD ($)
Environmental Matters
Clean power plan, optional extension period					2 years
Four Corners \| New Mexico Tax Matter
Environmental Matters
Coal severance surtax, penalty, and interest				$ 30.0
Litigation settlement awarded (against), amount			$ (1.0)
Arizona Public Service Company \| Letter of Credit Expiring in 2016 and 2017
Financial Assurances
Outstanding letters of credit					$ 52.0
Arizona Public Service Company \| Letters of Credit Expiring in 2017
Financial Assurances
Surety bonds expiring, amount					$ 150.0
Arizona Public Service Company \| Four Corners \| New Mexico Tax Matter
Environmental Matters
Share of the assessment				12.0
Partial payment of assessment				$ 0.8
Litigation settlement awarded (against), amount			$ (0.8)
4C Acquisition, LLC \| Four Corners Units 4 and 5
Environmental Matters
Percentage of share of cost of control					7.00%
Regional Haze Rules \| Arizona Public Service Company \| Four Corners Units 4 and 5
Environmental Matters
Percentage of share of cost of control					63.00%
Expected environmental cost					$ 400.0
Regional Haze Rules \| Arizona Public Service Company \| Natural gas tolling contract obligations \| Four Corners Units 4 and 5
Environmental Matters
Additional percentage share of cost of control					7.00%
Regional Haze Rules \| Arizona Public Service Company \| Four Corners \| Four Corners Units 4 and 5
Environmental Matters
Site contingency increase in loss exposure not accrued, best estimate					$ 45.0
Regional Haze Rules \| Arizona Public Service Company \| Navajo Plant
Environmental Matters
Expected environmental cost					200.0
Regional Haze Rules \| Arizona Public Service Company \| Cholla
Environmental Matters
Expected environmental cost					100.0
Mercury and air toxic standards (MATS) \| Arizona Public Service Company \| Navajo Plant
Environmental Matters
Expected environmental cost					1.0
Mercury and air toxic standards (MATS) \| Arizona Public Service Company \| Cholla
Environmental Matters
Expected environmental cost					8.0
Coal combustion waste \| Arizona Public Service Company \| Four Corners
Environmental Matters
Site contingency increase in loss exposure not accrued, best estimate					15.0
Coal combustion waste \| Arizona Public Service Company \| Navajo Plant
Environmental Matters
Site contingency increase in loss exposure not accrued, best estimate					1.0
Coal combustion waste \| Arizona Public Service Company \| Navajo Plant \| Boron Inclusion on List of Groundwater Constituents
Environmental Matters
Industry litigation, period to complete rulemaking proceeding		3 years
Payment Guarantee
Financial Assurances
Number of parental guarantees \| guarantee	2
Minimum \| Coal combustion waste \| Arizona Public Service Company \| Cholla
Environmental Matters
Site contingency increase in loss exposure not accrued, best estimate					5.0
Maximum \| Coal combustion waste \| Arizona Public Service Company \| Cholla
Environmental Matters
Site contingency increase in loss exposure not accrued, best estimate					$ 40.0