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Segment Information - Narrative (Details) - Adjustments for New Accounting Pronouncement [Member] $ in Millions | 9 Months Ended
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Sep. 30, 2015 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
Previously reported amounts reclassified | $ 40.3
Public Service Company of New Mexico [Member] |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
Previously reported amounts reclassified | 22.1
Texas-New Mexico Power Company [Member] |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
Previously reported amounts reclassified | $ 10.4

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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 amount of a reclassification adjustment made to prior period financial statement amounts. + References No definition available. + Details
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- Details
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