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Commitments and Contingencies - Mining Royalty Rate (Details) - Continuous Highwall Mining - San Juan Generating Station - USD ($) $ in Millions | Dec. 31, 2020 | Aug. 31, 2013
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Public Utilities, General Disclosures [Line Items] |  |
Proposed retroactive surface mining royalty rate |  | 12.50%
Surface mining royalty rate applied between 2000 and 2003 | 8.00% |
Estimated underpaid surface mining royalties under proposed rate change | $ 5 |
PNM's share of estimated underpaid surface mining royalties under proposed rate change | 46.30% |

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- Definition Public Utilities, Estimated Underpaid Surface Mining Royalties Under Proposed Rate Change + References No definition available. + Details
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- Definition Public Utilities, PNM Share Estimated Underpaid Surface Mining Royalties under proposed rate change + References No definition available. + Details
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- Definition Public Utilities, Proposed Retroactive Surface Mining Royalty Rate + References No definition available. + Details
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- Details
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- Details
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