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Fair Value of Derivative and Other Financial Instruments - Defined Benefit Plans Disclosure (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Public Service Company of New Mexico | Pension Plan |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | $ 562,016 | $ 543,601
Fair value of plan assets at end of year | 489,978 | 562,016
Public Service Company of New Mexico | Pension Plan | Participation in PNMR Master Trust Investments: | Fair Value Measurement [Domain] |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 487,498 |
Fair value of plan assets at end of year | 412,790 | 487,498
Public Service Company of New Mexico | Pension Plan | Participation in PNMR Master Trust Investments: |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 562,266 |
Fair value of plan assets at end of year | 489,664 | 562,266
Public Service Company of New Mexico | Pension Plan | Participation in PNMR Master Trust Investments: | Estimate of Fair Value Measurement |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 74,768 |
Fair value of plan assets at end of year | 76,874 | 74,768
Public Service Company of New Mexico | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total fair value of plan assets owned | 69,703 | 81,177
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 80,356 | 72,694
Fair value of plan assets at end of year | 69,703 | 80,356
Public Service Company of New Mexico | Other Postretirement Benefits | Cash and cash equivalents |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 437 |
Fair value of plan assets at end of year | 190 | 437
Public Service Company of New Mexico | Other Postretirement Benefits | International funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 10,636 |
Fair value of plan assets at end of year |  | 10,636
Public Service Company of New Mexico | Other Postretirement Benefits | Domestic value |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 10,816 |
Fair value of plan assets at end of year |  | 10,816
Public Service Company of New Mexico | Other Postretirement Benefits | Domestic growth |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 6,710 |
Fair value of plan assets at end of year |  | 6,710
Public Service Company of New Mexico | Other Postretirement Benefits | Other funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 31,660 |
Fair value of plan assets at end of year |  | 31,660
Public Service Company of New Mexico | Other Postretirement Benefits | Mutual funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 20,918 |
Fair value of plan assets at end of year | 69,513 | 20,918
Public Service Company of New Mexico | Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Plan | Participation in PNMR Master Trust Investments: |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 140,218 |
Fair value of plan assets at end of year | 139,673 | 140,218
Public Service Company of New Mexico | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total fair value of plan assets owned | 32,515 | 38,881
Public Service Company of New Mexico | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Postretirement Benefits | Cash and cash equivalents |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 437 |
Fair value of plan assets at end of year | 190 | 437
Public Service Company of New Mexico | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Postretirement Benefits | International funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year |  | 0
Public Service Company of New Mexico | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Postretirement Benefits | Domestic value |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 10,816 |
Fair value of plan assets at end of year |  | 10,816
Public Service Company of New Mexico | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Postretirement Benefits | Domestic growth |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 6,710 |
Fair value of plan assets at end of year |  | 6,710
Public Service Company of New Mexico | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Postretirement Benefits | Other funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year |  | 0
Public Service Company of New Mexico | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Postretirement Benefits | Mutual funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 20,918 |
Fair value of plan assets at end of year | 32,325 | 20,918
Public Service Company of New Mexico | Significant Other Observable Inputs (Level 2) | Pension Plan | Participation in PNMR Master Trust Investments: |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 347,089 |
Fair value of plan assets at end of year | 272,829 | 347,089
Public Service Company of New Mexico | Significant Other Observable Inputs (Level 2) | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total fair value of plan assets owned | 37,188 | 42,296
Public Service Company of New Mexico | Significant Other Observable Inputs (Level 2) | Other Postretirement Benefits | Cash and cash equivalents |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 0 | 0
Public Service Company of New Mexico | Significant Other Observable Inputs (Level 2) | Other Postretirement Benefits | International funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 10,636 |
Fair value of plan assets at end of year |  | 10,636
Public Service Company of New Mexico | Significant Other Observable Inputs (Level 2) | Other Postretirement Benefits | Domestic value |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year |  | 0
Public Service Company of New Mexico | Significant Other Observable Inputs (Level 2) | Other Postretirement Benefits | Domestic growth |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year |  | 0
Public Service Company of New Mexico | Significant Other Observable Inputs (Level 2) | Other Postretirement Benefits | Other funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 31,660 |
Fair value of plan assets at end of year |  | 31,660
Public Service Company of New Mexico | Significant Other Observable Inputs (Level 2) | Other Postretirement Benefits | Mutual funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 37,188 | 0
Public Service Company of New Mexico | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 191 | 352
Fair value of plan assets at end of year | 288 | 191
Public Service Company of New Mexico | Significant Unobservable Inputs (Level 3) | U.S. government |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Actual return on assets sold during the period | (7) | 1
Actual return on assets still held at period end | (1) | (7)
Purchases | 192 | 92
Sales | (87) | (247)
Public Service Company of New Mexico | Significant Unobservable Inputs (Level 3) | Pension Plan | Participation in PNMR Master Trust Investments: |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 191 |
Fair value of plan assets at end of year | 288 | 191
Public Service Company of New Mexico | Significant Unobservable Inputs (Level 3) | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total fair value of plan assets owned | 0 | 0
Public Service Company of New Mexico | Significant Unobservable Inputs (Level 3) | Other Postretirement Benefits | Cash and cash equivalents |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 0 | 0
Public Service Company of New Mexico | Significant Unobservable Inputs (Level 3) | Other Postretirement Benefits | International funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year |  | 0
Public Service Company of New Mexico | Significant Unobservable Inputs (Level 3) | Other Postretirement Benefits | Domestic value |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year |  | 0
Public Service Company of New Mexico | Significant Unobservable Inputs (Level 3) | Other Postretirement Benefits | Domestic growth |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year |  | 0
Public Service Company of New Mexico | Significant Unobservable Inputs (Level 3) | Other Postretirement Benefits | Other funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year |  | 0
Public Service Company of New Mexico | Significant Unobservable Inputs (Level 3) | Other Postretirement Benefits | Mutual funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 0 | 0
Texas-New Mexico Power Company | Pension Plan |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 63,499 | 60,624
Fair value of plan assets at end of year | 55,074 | 63,499
Texas-New Mexico Power Company | Pension Plan | Participation in PNMR Master Trust Investments: | Fair Value Measurement [Domain] |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 53,273 |
Fair value of plan assets at end of year | 45,283 | 53,273
Texas-New Mexico Power Company | Pension Plan | Participation in PNMR Master Trust Investments: |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 63,533 |
Fair value of plan assets at end of year | 54,661 | 63,533
Texas-New Mexico Power Company | Pension Plan | Participation in PNMR Master Trust Investments: | Estimate of Fair Value Measurement |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 10,260 |
Fair value of plan assets at end of year | 9,378 | 10,260
Texas-New Mexico Power Company | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total fair value of plan assets owned | 8,791 | 10,145
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 10,002 | 8,544
Fair value of plan assets at end of year | 8,744 | 10,002
Texas-New Mexico Power Company | Other Postretirement Benefits | Cash and cash equivalents |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 149 |
Fair value of plan assets at end of year | 66 | 149
Texas-New Mexico Power Company | Other Postretirement Benefits | International funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 1,597 |
Fair value of plan assets at end of year |  | 1,597
Texas-New Mexico Power Company | Other Postretirement Benefits | Domestic value |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 293 |
Fair value of plan assets at end of year |  | 293
Texas-New Mexico Power Company | Other Postretirement Benefits | Domestic growth |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 1,410 |
Fair value of plan assets at end of year |  | 1,410
Texas-New Mexico Power Company | Other Postretirement Benefits | Other funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 4,011 |
Fair value of plan assets at end of year |  | 4,011
Texas-New Mexico Power Company | Other Postretirement Benefits | Mutual funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 2,685 |
Fair value of plan assets at end of year | 8,725 | 2,685
Texas-New Mexico Power Company | Quoted Prices in Active Markets for Identical Assets (Level 1) | Pension Plan | Participation in PNMR Master Trust Investments: |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 15,244 |
Fair value of plan assets at end of year | 15,149 | 15,244
Texas-New Mexico Power Company | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total fair value of plan assets owned | 3,789 | 4,537
Texas-New Mexico Power Company | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Postretirement Benefits | Cash and cash equivalents |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 149 |
Fair value of plan assets at end of year | 66 | 149
Texas-New Mexico Power Company | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Postretirement Benefits | International funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year |  | 0
Texas-New Mexico Power Company | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Postretirement Benefits | Domestic value |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 293 |
Fair value of plan assets at end of year |  | 293
Texas-New Mexico Power Company | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Postretirement Benefits | Domestic growth |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 1,410 |
Fair value of plan assets at end of year |  | 1,410
Texas-New Mexico Power Company | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Postretirement Benefits | Other funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year |  | 0
Texas-New Mexico Power Company | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other Postretirement Benefits | Mutual funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 2,685 |
Fair value of plan assets at end of year | 3,723 | 2,685
Texas-New Mexico Power Company | Significant Other Observable Inputs (Level 2) | Pension Plan | Participation in PNMR Master Trust Investments: |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 38,008 |
Fair value of plan assets at end of year | 30,101 | 38,008
Texas-New Mexico Power Company | Significant Other Observable Inputs (Level 2) | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total fair value of plan assets owned | 5,002 | 5,608
Texas-New Mexico Power Company | Significant Other Observable Inputs (Level 2) | Other Postretirement Benefits | Cash and cash equivalents |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 0 | 0
Texas-New Mexico Power Company | Significant Other Observable Inputs (Level 2) | Other Postretirement Benefits | International funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 1,597 |
Fair value of plan assets at end of year |  | 1,597
Texas-New Mexico Power Company | Significant Other Observable Inputs (Level 2) | Other Postretirement Benefits | Domestic value |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year |  | 0
Texas-New Mexico Power Company | Significant Other Observable Inputs (Level 2) | Other Postretirement Benefits | Domestic growth |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year |  | 0
Texas-New Mexico Power Company | Significant Other Observable Inputs (Level 2) | Other Postretirement Benefits | Other funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 4,011 |
Fair value of plan assets at end of year |  | 4,011
Texas-New Mexico Power Company | Significant Other Observable Inputs (Level 2) | Other Postretirement Benefits | Mutual funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 5,002 | 0
Texas-New Mexico Power Company | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 21 | 38
Fair value of plan assets at end of year | 33 | 21
Texas-New Mexico Power Company | Significant Unobservable Inputs (Level 3) | U.S. government |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Actual return on assets sold during the period | (1) | 0
Actual return on assets still held at period end | 0 | (1)
Purchases | 23 | 10
Sales | (10) | (26)
Texas-New Mexico Power Company | Significant Unobservable Inputs (Level 3) | Pension Plan | Participation in PNMR Master Trust Investments: |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 21 |
Fair value of plan assets at end of year | 33 | 21
Texas-New Mexico Power Company | Significant Unobservable Inputs (Level 3) | Other Postretirement Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total fair value of plan assets owned | 0 | 0
Texas-New Mexico Power Company | Significant Unobservable Inputs (Level 3) | Other Postretirement Benefits | Cash and cash equivalents |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 0 | 0
Texas-New Mexico Power Company | Significant Unobservable Inputs (Level 3) | Other Postretirement Benefits | International funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year |  | 0
Texas-New Mexico Power Company | Significant Unobservable Inputs (Level 3) | Other Postretirement Benefits | Domestic value |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year |  | 0
Texas-New Mexico Power Company | Significant Unobservable Inputs (Level 3) | Other Postretirement Benefits | Domestic growth |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year |  | 0
Texas-New Mexico Power Company | Significant Unobservable Inputs (Level 3) | Other Postretirement Benefits | Other funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year |  | 0
Texas-New Mexico Power Company | Significant Unobservable Inputs (Level 3) | Other Postretirement Benefits | Mutual funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 0 | 0
PNMR | Fair Value Measurement [Domain] |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 540,771 |
Fair value of plan assets at end of year | 458,073 | 540,771
PNMR |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 625,799 |
Fair value of plan assets at end of year | 544,325 | 625,799
PNMR | Cash and cash equivalents |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 7,697 |
Fair value of plan assets at end of year | 20,120 | 7,697
PNMR | International funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 42,048 |
Fair value of plan assets at end of year | 54,270 | 42,048
PNMR | Domestic value |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 37,026 |
Fair value of plan assets at end of year | 874 | 37,026
PNMR | Domestic growth |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 19,136 |
Fair value of plan assets at end of year | 143,517 | 19,136
PNMR | Other funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 25,099 |
Fair value of plan assets at end of year | 0 | 25,099
PNMR | U.S. government |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 215,535 |
Fair value of plan assets at end of year | 84,459 | 215,535
PNMR | International government |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 117,572 |
Fair value of plan assets at end of year | 5,721 | 117,572
PNMR | Municipals |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 11,438 |
Fair value of plan assets at end of year | 9,558 | 11,438
PNMR | Corporate and other |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 65,220 |
Fair value of plan assets at end of year | 139,554 | 65,220
PNMR | Private equity funds | Estimate of Fair Value Measurement |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 22,281 |
Fair value of plan assets at end of year | 18,021 | 22,281
PNMR | Hedge funds | Estimate of Fair Value Measurement |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 45,615 |
Fair value of plan assets at end of year | 45,589 | 45,615
PNMR | Real estate funds | Estimate of Fair Value Measurement |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 17,132 |
Fair value of plan assets at end of year | 22,642 | 17,132
PNMR | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 155,462 |
Fair value of plan assets at end of year | 154,822 | 155,462
PNMR | Quoted Prices in Active Markets for Identical Assets (Level 1) | Cash and cash equivalents |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 7,697 |
Fair value of plan assets at end of year | 20,120 | 7,697
PNMR | Quoted Prices in Active Markets for Identical Assets (Level 1) | International funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 54,270 | 0
PNMR | Quoted Prices in Active Markets for Identical Assets (Level 1) | Domestic value |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 37,026 |
Fair value of plan assets at end of year | 0 | 37,026
PNMR | Quoted Prices in Active Markets for Identical Assets (Level 1) | Domestic growth |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 19,136 |
Fair value of plan assets at end of year | 0 | 19,136
PNMR | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 0 | 0
PNMR | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. government |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 80,482 | 0
PNMR | Quoted Prices in Active Markets for Identical Assets (Level 1) | International government |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 91,603 |
Fair value of plan assets at end of year | 0 | 91,603
PNMR | Quoted Prices in Active Markets for Identical Assets (Level 1) | Municipals |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 0 | 0
PNMR | Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate and other |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | (50) | 0
PNMR | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 385,097 |
Fair value of plan assets at end of year | 302,930 | 385,097
PNMR | Significant Other Observable Inputs (Level 2) | Cash and cash equivalents |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 0 | 0
PNMR | Significant Other Observable Inputs (Level 2) | International funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 42,048 |
Fair value of plan assets at end of year | 0 | 42,048
PNMR | Significant Other Observable Inputs (Level 2) | Domestic value |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 874 | 0
PNMR | Significant Other Observable Inputs (Level 2) | Domestic growth |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 143,517 | 0
PNMR | Significant Other Observable Inputs (Level 2) | Other funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 25,099 |
Fair value of plan assets at end of year | 0 | 25,099
PNMR | Significant Other Observable Inputs (Level 2) | U.S. government |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 215,323 |
Fair value of plan assets at end of year | 3,977 | 215,323
PNMR | Significant Other Observable Inputs (Level 2) | International government |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 25,969 |
Fair value of plan assets at end of year | 5,721 | 25,969
PNMR | Significant Other Observable Inputs (Level 2) | Municipals |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 11,438 |
Fair value of plan assets at end of year | 9,558 | 11,438
PNMR | Significant Other Observable Inputs (Level 2) | Corporate and other |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 65,220 |
Fair value of plan assets at end of year | 139,283 | 65,220
PNMR | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 212 | 390
Fair value of plan assets at end of year | 321 | 212
PNMR | Significant Unobservable Inputs (Level 3) | Cash and cash equivalents |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 0 | 0
PNMR | Significant Unobservable Inputs (Level 3) | International funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 0 | 0
PNMR | Significant Unobservable Inputs (Level 3) | Domestic value |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 0 | 0
PNMR | Significant Unobservable Inputs (Level 3) | Domestic growth |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 0 | 0
PNMR | Significant Unobservable Inputs (Level 3) | Other funds |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 0 | 0
PNMR | Significant Unobservable Inputs (Level 3) | U.S. government |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 212 |
Actual return on assets sold during the period | (8) | 1
Actual return on assets still held at period end | (1) | (8)
Purchases | 215 | 102
Sales | (97) | (273)
Fair value of plan assets at end of year | 0 | 212
PNMR | Significant Unobservable Inputs (Level 3) | International government |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 0 | 0
PNMR | Significant Unobservable Inputs (Level 3) | Municipals |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | 0 | 0
PNMR | Significant Unobservable Inputs (Level 3) | Corporate and other |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 0 |
Fair value of plan assets at end of year | $ 321 | $ 0

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