Debt Instrument, Covenant, Debt To Capitalization Ratio

No definition available.

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- Definition

Debt Instrument, Prepayment Period

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Series Of Bond Issuance

+ References

No definition available.

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- Definition

Debt Instrument, Shelf Registration Statement for Unsecured Debt

+ References

No definition available.

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- Definition

Distribution Agreement, Sale Of Stock

+ References

No definition available.

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- Definition

Public Utilities, Maturity term over which financings require regulator approval

+ 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

Face amount per share of no-par value common stock.

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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.

+ Details

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- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Nominal or face amount used to calculate payment on derivative.

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- Definition

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

+ References

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- Definition

The effective interest rate at the end of the reporting period.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

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

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- Definition

Maximum period the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The amount for notes payable (written promise to pay), due to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Financing - Financing Activities (Details)															12 Months Ended
Financing - Financing Activities (Details)	Nov. 10, 2022 USD ($) $ / shares	Oct. 31, 2022 USD ($) derivative	Sep. 30, 2022 USD ($) derivative	Aug. 05, 2022 USD ($)	May 20, 2022 USD ($)	May 02, 2022 USD ($) derivative	Jan. 24, 2022 USD ($)	Dec. 02, 2021 USD ($)	Jul. 14, 2021 USD ($)	Jun. 18, 2021 USD ($)	May 18, 2021 USD ($)	Mar. 09, 2021 USD ($)	Dec. 22, 2020 USD ($)	Dec. 21, 2020 USD ($)	Dec. 31, 2022 USD ($) $ / shares	Dec. 31, 2017 USD ($) derivative	Jun. 01, 2022 USD ($) derivative	Apr. 27, 2022 USD ($) bond	Dec. 31, 2021 USD ($) $ / shares	Oct. 01, 2021 USD ($)	Aug. 16, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 30, 2020 USD ($)
Debt Instrument [Line Items]
Common stock, no par value (in dollars per share) \| $ / shares															$ 0				$ 0
Cash flow hedge derivative instrument assets at fair value															$ 11,100,000
Interest rate contract
Debt Instrument [Line Items]
Number of derivatives \| derivative																3
Interest rate contract \| Cash Flow Hedge
Debt Instrument [Line Items]
Derivative asset, number of instruments held \| derivative																	2
PNMR 2022 ATM Program
Debt Instrument [Line Items]
Distribution agreement, sale of stock	$ 200,000,000
Common stock, no par value (in dollars per share) \| $ / shares	$ 0
PNMR 2020 Delayed-Draw Term Loan
Debt Instrument [Line Items]
Available borrowing capacity												$ 220,000,000
Term loans													$ 300,000,000
Proceeds from long-term lines of credit													80,000,000
PNMR 2020 Term Loan
Debt Instrument [Line Items]
Term loans														$ 150,000,000
PNMR 2018 Two-Year Term Loan due December 2020
Debt Instrument [Line Items]
Debt instrument, term														2 years
Variable Rate Short-Term Debt
Debt Instrument [Line Items]
Aggregate principal amount																$ 50,000,000
Term of derivatives																4 years
Variable Rate Short-Term Debt \| Interest rate 1
Debt Instrument [Line Items]
Fixed interest rate																1.926%
Variable Rate Short-Term Debt \| Interest rate 2
Debt Instrument [Line Items]
Fixed interest rate																1.823%
Variable Rate Short-Term Debt \| Interest rate 3
Debt Instrument [Line Items]
Fixed interest rate																1.629%
Variable Rate Debt \| Interest rate contract \| Cash Flow Hedge
Debt Instrument [Line Items]
Debt instrument, term			15 months		19 months	20 months
Derivative asset, number of instruments held \| derivative			2			2
Fixed interest rate					2.52%	2.65%
Derivative asset, notional amount			$ 200,000,000
Derivative, notional amount					$ 100,000,000
Variable Rate Debt, Tranche 1 \| Interest rate contract \| Cash Flow Hedge
Debt Instrument [Line Items]
Variable interest rate			4.17%
Derivative asset, notional amount			$ 100,000,000			$ 150,000,000
Variable Rate Debt, Tranche 2 \| Interest rate contract \| Cash Flow Hedge
Debt Instrument [Line Items]
Variable interest rate			4.18%
Derivative asset, notional amount			$ 100,000,000			$ 200,000,000
Fixed Rate Debt \| Interest rate contract \| Cash Flow Hedge
Debt Instrument [Line Items]
Debt instrument, term		14 months
Derivative asset, number of instruments held \| derivative		2
Fixed Rate Debt, Tranche 1 \| Interest rate contract \| Cash Flow Hedge
Debt Instrument [Line Items]
Fixed interest rate		4.66%
Derivative asset, notional amount		$ 100,000,000
Fixed Rate, Tranche 2 \| Interest rate contract \| Cash Flow Hedge
Debt Instrument [Line Items]
Fixed interest rate		4.65%
Derivative asset, notional amount		$ 200,000,000
Maximum
Debt Instrument [Line Items]
Short-term debt - affiliate															150,000,000
PNM and TNMP
Debt Instrument [Line Items]
Short-term debt - affiliate															$ 0				$ 0
PNM
Debt Instrument [Line Items]
Maturity term over which financings require regulator approval (more than)															18 months
Common stock, no par value (in dollars per share) \| $ / shares															$ 0				$ 0
PNM \| PNM 2019 $— Million Term Loan due June 2021
Debt Instrument [Line Items]
Aggregate principal amount																						$ 40,000,000
Repayments of debt										$ 40,000,000
PNMR
Debt Instrument [Line Items]
Short-term debt - affiliate															$ 5,300,000				$ 6,400,000
PNMR \| PNMR 2018 Two-Year Term Loan due December 2020
Debt Instrument [Line Items]
Repayments of debt													$ 220,000,000
PNMR \| PNMR 2021 Delayed-Draw Term Loan due May 2025
Debt Instrument [Line Items]
Term loans															1,000,000,000				900,000,000
PNMR Development
Debt Instrument [Line Items]
Financing capacity											$ 40,000,000
Short-term debt - affiliate															$ 0				0
Line of Credit \| PNMR 2021 Delayed-Draw Term Loan due May 2025 \| Revolving Credit Facility
Debt Instrument [Line Items]
Proceeds from long-term lines of credit							$ 100,000,000	$ 50,000,000			850,000,000
Interest rates on outstanding borrowings															5.37%
Line of Credit \| PNMR Development Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Repayments of debt											40,000,000
Line of Credit \| PNMR Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Repayments of debt											92,100,000
Line of Credit \| PNM 2022 Delayed-Draw Term Loan \| Revolving Credit Facility
Debt Instrument [Line Items]
Proceeds from long-term lines of credit			$ 45,000,000	$ 180,000,000
Financing capacity				$ 225,000,000
Line of Credit \| PNMR and PNMR Development
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%
Senior Unsecured Notes \| PNMR 3.25% 2018 SUNs due March 2021
Debt Instrument [Line Items]
Aggregate principal amount																						$ 300,000,000
Stated percentage																						3.25%
Repayments of debt												$ 80,000,000
Senior Unsecured Notes \| PNM
Debt Instrument [Line Items]
Shelf registration statement, capacity of issuance (up to)															$ 650,000,000
Senior Unsecured Notes \| PNM \| PNM 2021 $75.0 Million Term Loan due December 2022
Debt Instrument [Line Items]
Term loans															$ 0				75,000,000.0
Medium-term Notes \| PNMR Development Term Loan due January 2022
Debt Instrument [Line Items]
Aggregate principal amount																			65,000,000			$ 65,000,000	$ 90,000,000
Repayments of debt											65,000,000
Medium-term Notes \| PNMR 2019 Term Loan
Debt Instrument [Line Items]
Aggregate principal amount																						150,000,000
Medium-term Notes \| PNMR 2021 Delayed-Draw Term Loan due May 2025
Debt Instrument [Line Items]
Repayments of debt											65,000,000
Bonds \| PNMR 2020 Delayed-Draw Term Loan
Debt Instrument [Line Items]
Repayments of debt											300,000,000
Bonds \| PNMR 2019 Term Loan
Debt Instrument [Line Items]
Repayments of debt											150,000,000
Bonds \| PNMR 2020 Term Loan
Debt Instrument [Line Items]
Repayments of debt											150,000,000
Bonds \| PNMR 2018 Two-Year Term Loan due December 2020
Debt Instrument [Line Items]
Repayments of debt														$ 50,000,000
Bonds \| PNMR 2021 Delayed-Draw Term Loan due May 2025
Debt Instrument [Line Items]
Repayments of debt											$ 150,000,000
Bonds \| Pollution Control Revenue Bonds Due June 2020
Debt Instrument [Line Items]
Term loans																						100,300,000
Bonds \| PNM 2021 Fixed Rate PCRBs
Debt Instrument [Line Items]
Stated percentage																				0.875%
Bonds \| Pollution Control Revenue Bonds, Due 2033
Debt Instrument [Line Items]
Stated percentage																				2.15%
Term loans																				$ 146,000,000		$ 146,000,000
Bonds \| PNM \| PNM 2021 $75.0 Million Term Loan due December 2022
Debt Instrument [Line Items]
Variable interest rate															5.09%
Bonds \| PNM \| Pollution Control Revenue Bonds
Debt Instrument [Line Items]
Term loans																	$ 31,500,000		104,500,000
Bonds \| PNM \| Pollution Control Revenue Bonds Due June 2038
Debt Instrument [Line Items]
Aggregate principal amount																	36,000,000		$ 36,000,000
Stated percentage																			1.05%
Bonds \| PNM \| Pollution Control Revenue Bonds Due June 2040, 1
Debt Instrument [Line Items]
Aggregate principal amount																	$ 37,000,000		$ 37,000,000
Stated percentage																			2.125%
Bonds \| PNM \| Pollution Control Revenue Bonds Due June 2040, 2
Debt Instrument [Line Items]
Aggregate principal amount																			$ 11,500,000
Stated percentage																			1.20%
Bonds \| PNM \| Pollution Control Revenue Bonds Due June 2042
Debt Instrument [Line Items]
Aggregate principal amount																			$ 20,000,000
Stated percentage																			2.45%
Bonds \| PNM \| Pollution Control Revenue Bonds Due June 2024
Debt Instrument [Line Items]
Stated percentage																	3.00%
Bonds \| Texas-New Mexico Power Company \| TNMP 2022 Bond Purchase Agreement
Debt Instrument [Line Items]
Aggregate principal amount																		$ 160,000,000
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 percentage																		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 percentage																		3.81%
Notes Payable to Banks \| PNM \| PNM 2021 $75.0 Million Term Loan due December 2022
Debt Instrument [Line Items]
Aggregate principal amount										$ 75,000,000
Senior Notes \| PNM 2020 SUNs
Debt Instrument [Line Items]
Stated percentage									5.35%
Repayments of debt									$ 160,000,000
Senior Notes \| PNM 2021 SUNs At 2.59 Percent Due July 15, 2033
Debt Instrument [Line Items]
Aggregate principal amount																			$ 80,000,000
Stated percentage																			2.59%
Senior Notes \| PNM 2021 SUNs At 3.14 Percent Due July 15, 2041
Debt Instrument [Line Items]
Aggregate principal amount																			$ 80,000,000
Stated percentage																			3.14%
Senior Notes \| 2.29% Senior Unsecured Notes Due December 30, 2031
Debt Instrument [Line Items]
Aggregate principal amount								$ 50,000,000
Stated percentage																			2.29%
Senior Notes \| 2.97% Senior Unsecured Notes Due December 30, 2041
Debt Instrument [Line Items]
Aggregate principal amount																			$ 100,000,000
Stated percentage																			2.97%
Secured Debt \| Texas-New Mexico Power Company \| TNMP 2021 Bond Purchase Agreement
Debt Instrument [Line Items]
Aggregate principal amount									$ 65,000,000												$ 65,000,000
Stated percentage																					2.44%
Secured Debt \| Texas-New Mexico Power Company \| TNMP First Mortgage Bonds
Debt Instrument [Line Items]
Aggregate principal amount															$ 750,000,000
Debt instrument, prepayment period															30 days
Debt instrument, redemption price, percentage of principal amount redeemed															100.00%