Debt Instrument, Covenant, Debt To Capitalization Ratio

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- Definition

Debt Instrument, Number Of Debt Issuances

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- Definition

Debt Instrument, Series Of Bond Issuance

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- Definition

Public Utilities, Maturity Term Over Which Financings Require Regulator Approval

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- Definition

Sale Of Stock, Distribution Agreement, Aggregate Value

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- Definition

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

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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.

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- Definition

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

+ References

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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.

+ References

No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payments on the derivative asset.

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- Definition

The number of derivative instruments of a particular derivative asset or group of derivative assets held by the entity.

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- Definition

Aggregate fair value of all derivative assets designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

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- Definition

Nominal or face amount used to calculate payment on derivative.

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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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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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Financing - Financing Activities (Details)								3 Months Ended
Financing - Financing Activities (Details)	May 04, 2023 USD ($) derivative	Mar. 15, 2023 USD ($) derivative	Nov. 10, 2022 USD ($)	Oct. 31, 2022 USD ($) derivative	Sep. 30, 2022 USD ($) derivative	May 20, 2022 USD ($)	May 02, 2022 USD ($) derivative	Mar. 31, 2023 USD ($) $ / shares shares	Apr. 28, 2023 USD ($) numberOfAMIMeter bond	Apr. 27, 2022 USD ($) bond
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
At-The-Market
Debt Instrument [Line Items]
Distribution agreement			$ 200,000,000
Variable Rate Debt \| Interest rate contract \| Cash Flow Hedge
Debt Instrument [Line Items]
Number of instruments held \| derivative				2	2		2
Term of loan				14 months	15 months	19 months	20 months
Derivative asset, notional amount				$ 200,000,000	$ 200,000,000
Derivative, notional amount						$ 100,000,000
Fixed interest rate						2.52%	2.65%
Derivative instruments in hedges, fair value								$ 8,700,000
Variable Rate Debt \| Interest rate contract \| Cash Flow Hedge \| Other Current Assets
Debt Instrument [Line Items]
Derivative instruments in hedges, fair value								8,400,000
Variable Rate Debt \| Interest rate contract \| Cash Flow Hedge \| Other Deferred Costs Net Including Deferred Finance Costs
Debt Instrument [Line Items]
Derivative instruments in hedges, fair value								$ 300,000
Variable Rate Debt \| Interest rate contract \| Cash Flow Hedge \| Subsequent event
Debt Instrument [Line Items]
Number of instruments held \| derivative	3
Derivative asset, notional amount	$ 300,000,000
Variable Rate Debt, Tranche 1 \| Interest rate contract \| Cash Flow Hedge
Debt Instrument [Line Items]
Term of loan		6 months
Derivative asset, notional amount		$ 150,000,000		$ 100,000,000	$ 100,000,000		$ 150,000,000
Fixed interest rate		4.57%		4.66%
Variable interest rate					4.17%
Variable Rate Debt, Tranche 1 \| Interest rate contract \| Cash Flow Hedge \| Subsequent event
Debt Instrument [Line Items]
Term of loan	12 months
Derivative asset, notional amount	$ 100,000,000
Fixed interest rate	3.32%
Variable Rate Debt, Tranche 2 \| Interest rate contract \| Cash Flow Hedge
Debt Instrument [Line Items]
Term of loan		12 months
Derivative asset, notional amount		$ 150,000,000		$ 100,000,000	$ 100,000,000		$ 200,000,000
Fixed interest rate		3.57%		4.65%
Variable interest rate					4.18%
Variable Rate Debt, Tranche 2 \| Interest rate contract \| Cash Flow Hedge \| Subsequent event
Debt Instrument [Line Items]
Term of loan	12 months
Derivative asset, notional amount	$ 100,000,000
Fixed interest rate	3.32%
Variable Rate Debt, Tranche 3 \| Interest rate contract \| Cash Flow Hedge
Debt Instrument [Line Items]
Term of loan		12 months
Derivative asset, notional amount		$ 150,000,000
Fixed interest rate		3.62%
Variable Rate Debt, Tranche 3 \| Interest rate contract \| Cash Flow Hedge \| Subsequent event
Debt Instrument [Line Items]
Term of loan	12 months
Derivative asset, notional amount	$ 100,000,000
Fixed interest rate	3.38%
Variable Rate Debt, Tranche 2 And 3 \| Interest rate contract \| Cash Flow Hedge
Debt Instrument [Line Items]
Number of instruments held \| derivative		2
Derivative asset, notional amount		$ 300,000,000
PNM
Debt Instrument [Line Items]
Maturity term over which financings require regulator approval (more than)								18 months
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%
Unsecured Debt \| PNM \| PNM 2023 Note Purchase Agreement \| Subsequent event
Debt Instrument [Line Items]
Aggregate principal amount									$ 200,000,000
Number of debt issuances \| numberOfAMIMeter									2
Unsecured Debt \| PNM \| PNM 2023 SUNs At 5.1%, Due April 28, 2035 \| Subsequent event
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 \| Subsequent event
Debt Instrument [Line Items]
Aggregate principal amount									$ 50,000,000
Stated interest rate									5.92%
Mortgage Bonds \| PNM \| TNMP 2023 Bond Purchase Agreement \| Subsequent event
Debt Instrument [Line Items]
Debt instrument, series of bond issuance \| bond									2
Mortgage Bonds \| Texas-New Mexico Power Company \| TNMP 2023 Bond Purchase Agreement \| Subsequent event
Debt Instrument [Line Items]
Aggregate principal amount									$ 185,000,000
Mortgage Bonds \| Texas-New Mexico Power Company \| TNMP 2023 Bond Purchase Agreement At 5.01%, Due April 28, 2033 \| Subsequent event
Debt Instrument [Line Items]
Aggregate principal amount									$ 130.0
Stated interest rate									5.01%
Mortgage Bonds \| Texas-New Mexico Power Company \| TNMP 2023 Bond Purchase Agreement At 5.47%, Due July 28, 2053 \| Subsequent event
Debt Instrument [Line Items]
Aggregate principal amount									$ 55.0
Stated interest rate									5.47%
Bonds \| PNMR 2021 Delayed-Draw Term Loan
Debt Instrument [Line Items]
Variable interest rate								5.84%
Bonds \| PNM \| PNM 2021 75 Million Term Loan
Debt Instrument [Line Items]
Variable interest rate								5.60%
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%