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Significant Accounting Policies and Responsibility for Financial Statements (Details) - USD ($) | 1 Months Ended | 3 Months Ended
--- | --- | ---
Feb. 29, 2020 | Feb. 28, 2019 | Mar. 31, 2020 | Mar. 31, 2019
Business Acquisition [Line Items] |  |  |  |
Payment defaults under agreements |  |  | $ 0 |
Dividends declared per common share (dollars per share) | $ 0.3075 | $ 0.29 | $ 0.3075 | $ 0.2900
Dividends declared on common stock |  |  | $ 24,493,000 | $ 23,099,000
PNM |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Dividends declared on common stock |  |  | 40,654,000 |
Texas-New Mexico Power Company |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Dividends declared on common stock |  |  | $ 11,347,000 | $ 10,713,000

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- Definition Aggregate dividends declared during the period for each share of common stock outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
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- Details
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