Fair Value of Derivative and Other Financial Instruments - Maturities of Securities (Details) - PNMR and PNM $ in Thousands	Dec. 31, 2022 USD ($)
Available-for-Sale
Within 1 year	$ 40,339
After 1 year through 5 years	67,426
After 5 years through 10 years	70,608
After 10 years through 15 years	15,571
After 15 years through 20 years	12,825
After 20 years	32,211
Debt securities, available-for-sale	$ 238,980

Available-for-sale Securities, Debt Maturities, after Fifteen Years Through Twenty Years, Fair Value

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- Definition

Available-for-sale Securities, Debt Maturities, after Ten Years Through Fifteen Years, Fair Value

+ References

No definition available.

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- Definition

Available-for-sale Securities, Debt Maturities, after Twenty Years, Fair Value

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No definition available.

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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