Debt Instrument, Covenant, Debt To Capitalization Ratio

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- Definition

Debt Instrument, Number Of Debt Issuances

+ References

No definition available.

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- Definition

Debt Instrument, Series Of Bond Issuance

+ References

No definition available.

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- Definition

Public Utilities, Maturity Term Over Which Financings Require Regulator Approval

+ References

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- Definition

Sale Of Stock, Distribution Agreement, Aggregate Value

+ References

No definition available.

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- Definition

Fair value of all asset derivatives designated as cash flow hedging instruments.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The per share price of the Company's stock at which the contract holder of the freestanding contract has the right to purchase or sell the Company's stock at a future date.

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- Definition

The maximum number of shares that could be issued to net share settle a contract, if applicable. If a contract does not have a fixed or determinable maximum number of shares that may be required to be issued, disclose the fact that a potentially infinite number of shares could be issued to settle the contract.

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- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Financing - Financing Activities (Details)				3 Months Ended		6 Months Ended
Financing - Financing Activities (Details)	Jun. 30, 2023 USD ($)	May 13, 2023 USD ($)	Nov. 10, 2022 USD ($)	Jun. 30, 2023 USD ($) $ / shares shares	Mar. 31, 2023 $ / shares shares	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 01, 2023 USD ($)	May 16, 2023 USD ($)	Apr. 28, 2023 USD ($) bond debtInstrument	Dec. 31, 2022 USD ($)	Jun. 01, 2022 USD ($) bond	Apr. 27, 2022 USD ($) bond	Dec. 31, 2021 USD ($)
Debt Instrument [Line Items]
Repayments of long-term debt						$ 685,000,000	$ 104,500,000
Fair value of hedge agreements	$ 15,900,000			$ 15,900,000		15,900,000
Bank Of America, N.A.
Debt Instrument [Line Items]
Forward sale agreement (in shares) \| shares					504,452
Forward sale agreement (in dollars per share) \| $ / shares					$ 48.49
Wells Fargo Bank, N.A.
Debt Instrument [Line Items]
Forward sale agreement (in shares) \| shares					528,082
Forward sale agreement (in dollars per share) \| $ / shares					$ 48.30
MUFG Securities EMEA plc
Debt Instrument [Line Items]
Forward sale agreement (in shares) \| shares				1,049,116
Forward sale agreement (in dollars per share) \| $ / shares				$ 45.49
Other Current Assets
Debt Instrument [Line Items]
Fair value of hedge agreements	8,100,000			$ 8,100,000		8,100,000
Other Deferred Costs Net Including Deferred Finance Costs
Debt Instrument [Line Items]
Fair value of hedge agreements	$ 7,800,000			$ 7,800,000		$ 7,800,000
At-The-Market
Debt Instrument [Line Items]
Distribution agreement			$ 200,000,000
PNM 3.15% Senior Unsecured Notes, Due May 2023
Debt Instrument [Line Items]
Repayments of long-term debt		$ 55,000,000
PNM
Debt Instrument [Line Items]
Maturity term over which financings require regulator approval (more than)						18 months
Repayments of long-term debt						$ 185,000,000	$ 104,500,000
Number of debt issuances \| bond												2
Line of credit
Debt Instrument [Line Items]
Ratio of debt to capital (less than or equal to)						70.00%
Line of credit \| PNM and TNMP
Debt Instrument [Line Items]
Ratio of debt to capital (less than or equal to)						65.00%
Bonds \| PCRB 1.10%, Due June 2040
Debt Instrument [Line Items]
Aggregate principal amount											$ 130,000,000
Stated interest rate											1.10%
Bonds \| PCRB 3.90%, Due June 2028
Debt Instrument [Line Items]
Aggregate principal amount								$ 130,000,000
Stated interest rate								3.90%
Bonds \| PNMR 2021 Delayed-Draw Term Loan
Debt Instrument [Line Items]
Variable interest rate	6.15%			6.15%		6.15%
Bonds \| PNMR 2023 Delayed-Draw Term Loan
Debt Instrument [Line Items]
Variable interest rate	6.55%			6.55%		6.55%
Bonds \| PNM \| PCRB's
Debt Instrument [Line Items]
Long-term debt												$ 31,500,000		$ 104,500,000
Bonds \| PNM \| PCRB, 1.05%, Due January 2038
Debt Instrument [Line Items]
Stated interest rate														1.05%
Long-term debt														$ 36,000,000
Bonds \| PNM \| PCRB, 2.125% Due June 2040
Debt Instrument [Line Items]
Stated interest rate														2.125%
Long-term debt														$ 37,000,000
Bonds \| PNM \| PCRB, 1.20% Due June 2040
Debt Instrument [Line Items]
Stated interest rate														1.20%
Long-term debt														$ 11,500,000
Bonds \| PNM \| PCRB, 2.45% Due September 2042
Debt Instrument [Line Items]
Stated interest rate														2.45%
Long-term debt														$ 20,000,000
Bonds \| PNM \| PCRB, 3.00% Due June 2024 (1)
Debt Instrument [Line Items]
Aggregate principal amount												$ 36,000,000
Stated interest rate												3.00%
Bonds \| PNM \| PCRB, 3.00% Due June 2024 (2)
Debt Instrument [Line Items]
Aggregate principal amount												$ 37,000,000
Stated interest rate												3.00%
Bonds \| PNM \| PNM 2021 75 Million Term Loan
Debt Instrument [Line Items]
Variable interest rate	5.99%			5.99%		5.99%
Bonds \| Texas-New Mexico Power Company \| TNMP 2022 Bond Purchase Agreement
Debt Instrument [Line Items]
Aggregate principal amount													$ 160,000,000
Debt instrument, series of bond issuance \| bond													2
Bonds \| Texas-New Mexico Power Company \| TNMP 2022 Bond Purchase Agreement at 4.13% Due May 12, 2022
Debt Instrument [Line Items]
Aggregate principal amount													$ 65,000,000
Stated interest rate													4.13%
Bonds \| Texas-New Mexico Power Company \| TNMP 2022 Bond Purchase Agreement at 3.81% Due July 28, 2032
Debt Instrument [Line Items]
Aggregate principal amount													$ 95,000,000
Stated interest rate													3.81%
Unsecured Debt \| PNM, Due May 2026
Debt Instrument [Line Items]
Aggregate principal amount									$ 650,000,000
Unsecured Debt \| PNM 3.15% Senior Unsecured Notes, Due May 2023
Debt Instrument [Line Items]
Stated interest rate											3.15%
Unsecured Debt \| PNM \| PNM 3.15% Senior Unsecured Notes, Due May 2023
Debt Instrument [Line Items]
Aggregate principal amount										$ 55,000,000
Unsecured Debt \| PNM \| PNM 2023 Note Purchase Agreement
Debt Instrument [Line Items]
Aggregate principal amount										$ 200,000,000
Number of debt issuances \| debtInstrument										2
Unsecured Debt \| PNM \| PNM 2023 SUNs At 5.1%, Due April 28, 2035
Debt Instrument [Line Items]
Aggregate principal amount										$ 150,000,000
Stated interest rate										5.51%
Unsecured Debt \| PNM \| PNM 2023 SUNs At 5.92%, Due April 28, 2053
Debt Instrument [Line Items]
Aggregate principal amount										$ 50,000,000
Stated interest rate										5.92%
Secured Debt \| PNM 2023 Term Loan
Debt Instrument [Line Items]
Aggregate principal amount	$ 500,000,000			$ 500,000,000		$ 500,000,000
Variable rate	6.55%
Secured Debt \| PNM \| TNMP 2023 Bond Purchase Agreement
Debt Instrument [Line Items]
Debt instrument, series of bond issuance \| bond										2
Secured Debt \| Texas-New Mexico Power Company \| TNMP 2023 Bond Purchase Agreement
Debt Instrument [Line Items]
Aggregate principal amount										$ 185,000,000
Secured Debt \| Texas-New Mexico Power Company \| TNMP 2023 Bond Purchase Agreement At 5.01%, Due April 28, 2033
Debt Instrument [Line Items]
Aggregate principal amount										$ 130,000,000.0
Stated interest rate										5.01%
Secured Debt \| Texas-New Mexico Power Company \| TNMP 2023 Bond Purchase Agreement At 5.47%, Due July 28, 2053
Debt Instrument [Line Items]
Aggregate principal amount										$ 55,000,000.0
Stated interest rate										5.47%