Jointly Owned Plant, Number of Participants

No definition available.

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- Definition

Jointly Owned Utility Plant, Number of Units

+ References

No definition available.

+ Details

Name:	ee_JointlyOwnedUtilityPlantNumberOfUnits
Namespace Prefix:	ee_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The period end amount owned by the reporting utility of a jointly owned utility plant in service.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 10.C)
-URI http://asc.fasb.org/extlink&oid=6500719&loc=d3e659983-123033

+ Details

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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.

+ References

No definition available.

+ Details

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- Definition

The total period end amount of plant in service and construction in progress net of accumulated depreciation for the utility's share of jointly owned electricity generation plant.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The period end amount of construction work in progress at a jointly owned electricity generation plant.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The period end amount of accumulated depreciation in a jointly owned electricity generation plant.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

+ References

+ Details

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Data Type:	num:percentItemType
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- Details

Name:	us-gaap_JointlyOwnedUtilityPlantAxis=ee_PaloVerdeGeneratingStationMember
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- Details

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- Details

Name:	us-gaap_JointlyOwnedUtilityPlantAxis=ee_FourCornersGeneratingStationMember
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- Details

Name:	us-gaap_JointlyOwnedUtilityPlantAxis=us-gaap_JointlyOwnedElectricityGenerationPlantMember
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- Details

Name:	ee_PaloVerdeNuclearPlantGenerationUnitAxis=ee_PaloVerdeMember
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- Details

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Utility Plant, Palo Verde and Other Jointly-Owned Utility Plant (Summary of Jointly Owned Utility Plants) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) utilityplantunit	Jul. 06, 2016	Dec. 31, 2015 USD ($)
Palo Verde Generating Station
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant, Proportionate Ownership Share	15.80%
Jointly Owned Utility Plant, Number of Units \| utilityplantunit	3
Palo Verde Participants
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Plant, Number of Participants	6
Four Corners Generating Station
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant, Proportionate Ownership Share		7.00%
Other Jointly Owned Utlity Plant
Jointly Owned Utility Plant Interests [Line Items]
Electric plant in service	$ 67,621		$ 229,627
Accumulated depreciation	(44,377)		(181,886)
Construction work in progress	1,895		9,528
Total	25,139		57,269
Palo Verde \| Jointly Owned Nuclear Power Plant
Jointly Owned Utility Plant Interests [Line Items]
Electric plant in service	948,382		917,483
Accumulated depreciation	(320,000)		(304,060)
Construction work in progress	50,598		48,938
Total	$ 678,980		$ 662,361