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Income Taxes - Carryforwards (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Income Taxes, Impairment of Carryforwards |  |  |
State tax credit carryforwards | $ (425) | $ 425 | $ 0
State net operating loss carryforwards | 0 | 0 | 0
Charitable contribution carryforwards | 0 | 0 | 0
Compensation expense | 96 | (99) | 410
Income Taxes, Reserve Balances |  |  |
State tax credit carryforwards | 0 | 425 |
State net operating loss carryforwards | 0 | 0 |
Charitable contribution carryforwards | 0 | 0 |
Compensation expense | 407 | 311 |
Internal Revenue Service (IRS) |  |  |
Operating Loss Carryforwards [Line Items] |  |  |
Federal net operating loss carryforwards | 222,100 |  |
Federal tax credit carryforwards that expire beginning in 2023 | 121,400 |  |
Public Service Company of New Mexico |  |  |
Income Taxes, Impairment of Carryforwards |  |  |
State tax credit carryforwards | 0 | 0 | 0
State net operating loss carryforwards | 0 | 0 | 0
Charitable contribution carryforwards | 0 | 0 | 0
Compensation expense | 61 | (100) | 298
Income Taxes, Reserve Balances |  |  |
State tax credit carryforwards | 0 | 0 |
State net operating loss carryforwards | 0 | 0 |
Charitable contribution carryforwards | 0 | 0 |
Compensation expense | 259 | 198 |
Texas-New Mexico Power Company |  |  |
Income Taxes, Impairment of Carryforwards |  |  |
State tax credit carryforwards | 0 | 0 | 0
State net operating loss carryforwards | 0 | 0 | 0
Charitable contribution carryforwards | 0 | 0 | 0
Compensation expense | 35 | 2 | $ 111
Income Taxes, Reserve Balances |  |  |
State tax credit carryforwards | 0 | 0 |
State net operating loss carryforwards | 0 | 0 |
Charitable contribution carryforwards | 0 | 0 |
Compensation expense | $ 148 | $ 113 |

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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319 + Details
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- Definition The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
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