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

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Guarantor Obligations, Number of Parental Guarantees

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Industry Litigation, Period to Complete Rulemaking Proceeding

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Litigation Settlement, Abeyance Period

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

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Surety Bonds Expiring, Amount

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

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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
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-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

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

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-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
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Commitments and Contingencies - Environmental Matters and Financial Assurances (Details) $ in Millions					6 Months Ended
	Jun. 13, 2017 USD ($)	Apr. 28, 2017	Jul. 06, 2016 guarantee	Jun. 24, 2016	Jun. 30, 2017 USD ($)
Environmental Matters
Litigation abeyance period		60 days
Coal Supply Agreement Arbitration \| Four Corners
Environmental Matters
Damages sought	$ 27
Arizona Public Service Company \| Coal Supply Agreement Arbitration \| Four Corners
Environmental Matters
Damages sought	$ 17
Arizona Public Service Company \| Letter of Credit Expiring in 2016 and 2017
Financial Assurances
Outstanding letters of credit					$ 5
Arizona Public Service Company \| Letters of Credit Expiring in 2017
Financial Assurances
Surety bonds expiring, amount					$ 62
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
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
Regional Haze Rules \| Arizona Public Service Company \| Navajo Plant
Environmental Matters
Expected environmental cost					200
Regional Haze Rules \| Arizona Public Service Company \| Cholla
Environmental Matters
Expected environmental cost					100
Coal combustion waste \| Arizona Public Service Company \| Four Corners
Environmental Matters
Site contingency increase in loss exposure not accrued, best estimate					22
Coal combustion waste \| Arizona Public Service Company \| Navajo Plant
Environmental Matters
Site contingency increase in loss exposure not accrued, best estimate					1
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
Minimum \| Coal combustion waste \| Arizona Public Service Company \| Cholla
Environmental Matters
Site contingency increase in loss exposure not accrued, best estimate					$ 20
Payment Guarantee
Financial Assurances
Number of parental guarantees \| guarantee			3