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Schedule II - Valuation and Qualifying Accounts (Details) - SEC Schedule, 12-09, Reserve, Allowance For Doubtful Accounts - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at beginning of year | $ 1,163 | $ 1,406 | $ 1,081
Charged to costs and expenses | 3,527 | 2,835 | 3,360
Charged to other accounts | 6,070 | 0 | 0
Write-offs and other | 2,427 | 3,078 | 3,035
Balance at end of year | 8,333 | 1,163 | 1,406
Public Service Company of New Mexico |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at beginning of year | 1,163 | 1,406 | 1,081
Charged to costs and expenses | 3,482 | 2,790 | 3,338
Charged to other accounts | 6,070 | 0 | 0
Write-offs and other | 2,382 | 3,033 | 3,013
Balance at end of year | 8,333 | 1,163 | 1,406
Texas-New Mexico Power Company |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at beginning of year | 0 | 0 | 0
Charged to costs and expenses | 45 | 44 | 22
Charged to other accounts | 0 | 0 | 0
Write-offs and other | 45 | 44 | 22
Balance at end of year | $ 0 | $ 0 | $ 0

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- Definition Amount of valuation and qualifying accounts and reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column B)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column E)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690 + Details
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