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Income Taxes - Federal Income Tax Reform (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2022 | Dec. 31, 2022 | Dec. 31, 2018
Income Taxes [Line Items] |  |  |
Federal and state excess deferred income taxes |  | $ 23.6 |
Public Service Company of New Mexico |  |  |
Income Taxes [Line Items] |  |  |
Federal and state excess deferred income taxes |  | 14.4 |
TNMP |  |  |
Income Taxes [Line Items] |  |  |
Federal and state excess deferred income taxes |  | $ 9.2 |
NMPRC |  |  |
Income Taxes [Line Items] |  |  |
Proposed term for providing benefits to customers related to reduction in state corporate tax | 3 years |  | 23 years

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- Definition Public Utilities, Proposed Term to Provide Customers with Benefits Related to Reduction in State Corporate Income Tax Rate + References No definition available. + Details
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- Definition Amount of deferred federal, state, and local tax expense (benefit) attributable to income (loss) from continuing operations. Includes, but is not limited to, deferred national, regional, territorial, and provincial tax expense (benefit) for non-US (United States of America) jurisdiction. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 10 -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32672-109319 + Details
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