Fair Value of Derivative and Other Financial Instruments - Maturities of Debt Securities (Details) - PNMR and PNM $ in Thousands	Sep. 30, 2022 USD ($)
Available-for-Sale
Within 1 year	$ 38,433
After 1 year through 5 years	64,326
After 5 years through 10 years	70,355
After 10 years through 15 years	15,098
After 15 years through 20 years	11,897
After 20 years	30,072
Available-for-sale debt securities	$ 230,181

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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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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