Aggregate dividends declared during the period for each share of common stock outstanding.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.17)

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Significant Accounting Policies and Responsibility for Financial Statements - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended				3 Months Ended		9 Months Ended
	Sep. 30, 2015	Jul. 31, 2015	Sep. 30, 2014	Jul. 31, 2014	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Dividends Declared per Common Share (dollars per share)	$ 0.200	$ 0.200	$ 0.185	$ 0.185	$ 0.200	$ 0.185	$ 0.600	$ 0.555
Dividends declared and paid, cash dividends, common stock							$ 47,792
Adjustments for New Accounting Pronouncement [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Unamortized debt issuance expense	$ 13,900				$ 13,900		13,900
Public Service Company of New Mexico [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Dividends declared and paid, cash dividends, common stock							46,200	$ 30,300
Public Service Company of New Mexico [Member] \| Adjustments for New Accounting Pronouncement [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Unamortized debt issuance expense	9,700				9,700		9,700
Texas-New Mexico Power Company [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Dividends declared and paid, cash dividends, common stock							19,600	$ 16,300
Texas-New Mexico Power Company [Member] \| Adjustments for New Accounting Pronouncement [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Unamortized debt issuance expense	$ 4,000				$ 4,000		$ 4,000