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
Dec. 31, 2022 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	$ 112,063
Experience loss	27,531
Regulatory asset (liability) adjustment	(22,282)
Amortization recognized in net periodic benefit (income)	(6,967)
Amounts in AOCI not yet recognized in net periodic benefit cost at end of year	110,345
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	1,816
Experience loss	(1,628)
Regulatory asset (liability) adjustment	944
Amortization recognized in net periodic benefit (income)	(137)
Amounts in AOCI not yet recognized in net periodic benefit cost at end of year	995
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 loss	4,602
Regulatory asset (liability) adjustment	(4,602)
Amortization recognized in net periodic benefit (income)	0
Amounts in AOCI not yet recognized in net periodic benefit cost 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 loss	(2)
Regulatory asset (liability) adjustment	2
Amortization recognized in net periodic benefit (income)	0
Amounts in AOCI not yet recognized in net periodic benefit cost at end of year	$ 0

Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Actuarial (Gain) Loss, Regulatory Asset (Liability) Adjustment, before Tax

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- Definition

Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

+ References

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Amount, before tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

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