Condensed Consolidated Statements of Comprehensive Income (Loss) - PNM (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Unrealized holding gains (losses) arising during the period, income tax (expense) benefit	$ 1,657	$ 845
Reclassification adjustment for (gains) losses included in net earnings, income tax expense (benefit)	375	919
Pension liability adjustment, income tax expense (benefit)	(451)	(530)
PNM
Unrealized holding gains (losses) arising during the period, income tax (expense) benefit	1,657	845
Reclassification adjustment for (gains) losses included in net earnings, income tax expense (benefit)	375	919
Pension liability adjustment, income tax expense (benefit)	$ (451)	$ (530)

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income for defined benefit plan, attributable to parent.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount, before adjustment, of tax expense (benefit) for unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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