Goodwill, Reporting Unit, Sensitivity analysis, Percentage Increase in Expected Return on Equity

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- Definition

Goodwill, Reporting Unit, Sensitivity analysis, Reduced Percentage of Fair Value in Excess of Carrying Value

+ References

No definition available.

+ Details

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Name Accounting Standards Codification

-Topic 350

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-Paragraph 2

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

Percentage of fair value of reporting unit in excess of carrying amount.

+ References

No definition available.

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Goodwill; Impairments (Details) (USD $)	12 Months Ended
Goodwill; Impairments (Details) (USD $)	Dec. 31, 2008	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Apr. 01, 2014	Apr. 01, 2013	Apr. 01, 2012
Schedule of Goodwill and Other Intangible Assets [Line Items]
Goodwill		$ 278,297,000us-gaap_Goodwill	$ 278,297,000us-gaap_Goodwill	$ 278,297,000us-gaap_Goodwill
Goodwill, Impairment Loss	174,400,000us-gaap_GoodwillImpairmentLoss
Public Service Company of New Mexico [Member]
Schedule of Goodwill and Other Intangible Assets [Line Items]
Goodwill		51,600,000	51,600,000
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount					30.00%	27.00%
Goodwill, Reporting Unit, Sensitivity analysis, Percentage Increase in Expected Return on Equity					0.50%
Goodwill, Reporting Unit, Sensitivity analysis, Reduced Percentage of Fair Value in Excess of Carrying Value					23.00%	20.00%
Goodwill, Impairment Loss	51,100,000
Texas-New Mexico Power Company [Member]
Schedule of Goodwill and Other Intangible Assets [Line Items]
Goodwill		226,700,000	226,700,000
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount							26.00%
Goodwill, Impairment Loss	$ 34,500,000