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Pension and Other Postretirement Benefits - Pre-Tax Information about Prior Service Cost and Net Actuarial (Gain) loss in AOCI (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 USD ($)
Public Service Company of New Mexico | Pension Plan |
Net actuarial (gain) loss |
Amounts in AOCI not yet recognized in net periodic benefit cost (income) at beginning of year | $ 146,391
Experience (gain) loss | (21,393)
Regulatory asset (liability) adjustment | 15,211
Amortization recognized in net periodic benefit cost (income) | (8,131)
Amounts in AOCI not yet recognized in net periodic benefit cost (income) at end of year | 132,078
Public Service Company of New Mexico | Executive Retirement Program |
Net actuarial (gain) loss |
Amounts in AOCI not yet recognized in net periodic benefit cost (income) at beginning of year | 2,395
Experience (gain) loss | 78
Regulatory asset (liability) adjustment | (45)
Amortization recognized in net periodic benefit cost (income) | (169)
Amounts in AOCI not yet recognized in net periodic benefit cost (income) at end of year | 2,259
Texas-New Mexico Power Company | Pension Plan |
Net actuarial (gain) loss |
Amounts in AOCI not yet recognized in net periodic benefit cost (income) at beginning of year | 0
Experience (gain) loss | 3,860
Regulatory asset (liability) adjustment | (3,860)
Amortization recognized in net periodic benefit cost (income) | 0
Amounts in AOCI not yet recognized in net periodic benefit cost (income) at end of year | 0
Texas-New Mexico Power Company | Executive Retirement Program |
Net actuarial (gain) loss |
Amounts in AOCI not yet recognized in net periodic benefit cost (income) at beginning of year | 0
Experience (gain) loss | 58
Regulatory asset (liability) adjustment | (58)
Amortization recognized in net periodic benefit cost (income) | 0
Amounts in AOCI not yet recognized in net periodic benefit cost (income) at end of year | $ 0

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