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- Definition

Asset Purchase Agreement, Operating and Maintenance Cost Reimbursement Receivable

+ References

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+ Details

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- Definition

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

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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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- Definition

Equity Contribution Guarantees

+ References

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- References

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- Definition

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

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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.

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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://fasb.org/us-gaap/role/ref/legacyRef
-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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 10
-Subparagraph (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) - USD ($) $ in Millions			12 Months Ended
	Jul. 03, 2018	Jul. 06, 2016	Dec. 31, 2019
Financial Assurances
Equity contribution guarantees			$ 40.0
Letter of credit \| ARIZONA PUBLIC SERVICE COMPANY
Financial Assurances
Outstanding letters of credit			1.7
Four Corners \| NTEC
Environmental Matters [Abstract]
Option to purchase, ownership interest (as a percent)	7.00%	7.00%
Payment received for coal supply agreement	$ 70.0
Four Corners \| 4CA
Environmental Matters [Abstract]
Percentage share cost of control		7.00%
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]
Asset purchase agreement			$ 10.0
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			$ 400.0
Regional Haze Rules \| Four Corners Units 4 and 5 \| Four Corners \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Additional expected environment cost			$ 45.0
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			$ 22.0
Coal Combustion Waste \| Navajo Generating Station \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Additional expected environment cost			1.0
Coal Combustion Waste \| Minimum \| Cholla \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Additional expected environment cost			15.0
Coal Combustion Waste \| Minimum \| Cholla and Four Corners \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Additional expected environment cost			10.0
Coal Combustion Waste \| Maximum \| Cholla and Four Corners \| ARIZONA PUBLIC SERVICE COMPANY
Environmental Matters [Abstract]
Additional expected environment cost			15.0
Surety Bonds Expiring in 2020 \| ARIZONA PUBLIC SERVICE COMPANY
Financial Assurances
Surety bonds expiring, amount			$ 14.0