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.

+ Details

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- Definition

Public Utilities, Maturity Term Over Which Financings Require Regulator Approval

+ References

No definition available.

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- Definition

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

+ References

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Balance Type:	credit
Period Type:	instant

- 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.

+ References

+ Details

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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 price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

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- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

+ Details

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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.

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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+ Details

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

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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.

+ References

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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)										9 Months Ended
Financing - Financing Activities (Details)	Jul. 14, 2021 USD ($) bond_series	Jun. 18, 2021 USD ($)	May 18, 2021 USD ($)	Mar. 09, 2021 USD ($)	Dec. 22, 2020 USD ($)	Jun. 22, 2020 USD ($)	Apr. 30, 2020 USD ($)	Apr. 15, 2020 USD ($)	Jan. 01, 2020	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Oct. 22, 2021 USD ($)	Oct. 01, 2021	Sep. 23, 2021 USD ($) bond_series	Aug. 16, 2021 USD ($) bond_series	Dec. 31, 2020 USD ($)	Dec. 21, 2020 USD ($)	Aug. 31, 2020 USD ($)	Jul. 15, 2020 USD ($)	Jun. 30, 2020 USD ($)	Jun. 01, 2020 USD ($)	Apr. 24, 2020 USD ($) bond_series	Dec. 31, 2019 USD ($) bond_series	Mar. 09, 2018 USD ($)
Debt Instrument [Line Items]
Financing capacity										$ 40,000,000
Repayments of Long-term Debt										1,165,000,000	$ 752,845,000
Subsequent event
Debt Instrument [Line Items]
Remaining borrowing capacity												$ 798,800,000
PNMR 2020 Delayed-Draw Term Loan
Debt Instrument [Line Items]
Aggregate principal amount					$ 300,000,000
Proceeds from issuance of debt					$ 80,000,000
Remaining borrowing capacity				$ 220,000,000
PNM
Debt Instrument [Line Items]
Repayments of Long-term Debt										$ 200,000,000	$ 752,845,000
PNM \| Subsequent event
Debt Instrument [Line Items]
Remaining borrowing capacity												397,800,000
PNM \| PNM 2019 40 Million Term Loan
Debt Instrument [Line Items]
Repayments of debt		$ 40,000,000
PNM \| Maximum
Debt Instrument [Line Items]
Maturity term over which financings require regulator approval (more than)										18 months
Texas-New Mexico Power Company \| Subsequent event
Debt Instrument [Line Items]
Remaining borrowing capacity												$ 75,000,000
Line of credit
Debt Instrument [Line Items]
Ratio of debt to capital (less than or equal to)										70.00%
Line of credit \| PNMR 2021 Delayed-Draw Term Loan \| Revolving credit facility
Debt Instrument [Line Items]
Financing capacity			$ 1,000,000,000
Line of credit \| PNMR 2020 Delayed-Draw Term Loan \| Revolving credit facility
Debt Instrument [Line Items]
Proceeds from long-term lines of credit			850,000,000
Line of credit facility, interest rate at period end										0.94%
Line of credit \| PNMR Revolving Credit Facility \| Revolving credit facility
Debt Instrument [Line Items]
Repayments of debt			92,100,000
Line of credit \| PNMR Development Revolving Credit Facility \| Revolving credit facility
Debt Instrument [Line Items]
Repayments of debt			40,000,000
Line of credit \| PNM and TNMP
Debt Instrument [Line Items]
Ratio of debt to capital (less than or equal to)										65.00%
Line of credit \| PNM \| PNM Revolving Credit Facility
Debt Instrument [Line Items]
Repayments of debt							$ 100,000,000
Bonds
Debt Instrument [Line Items]
Repayments of debt						$ 302,500,000
Bonds \| City of Farmington, New Mexico
Debt Instrument [Line Items]
Aggregate principal amount																					$ 266,500,000
Bonds \| Pollution Control Revenue Bonds, Due 2033
Debt Instrument [Line Items]
Term loans																$ 146,000,000
Stated interest rate																2.15%
Bonds \| PNMR 2021 Delayed-Draw Term Loan
Debt Instrument [Line Items]
Variable interest rate										0.94%
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 \| Pollution Control Revenue Bonds
Debt Instrument [Line Items]
Term loans																							$ 100,300,000
Stated interest rate										0.11%
Variable interest rate										0.11%
Bonds \| Pollution Control Revenue Bonds, Due 2040
Debt Instrument [Line Items]
Term loans																							$ 40,000,000
Debt instrument, series of bond issuance \| bond_series																							2
Bonds \| Pollution Control Revenue Bonds, Due 2043, Series 1
Debt Instrument [Line Items]
Term loans																							$ 39,300,000
Bonds \| Pollution Control Revenue Bonds, Due 2043, Series 2
Debt Instrument [Line Items]
Term loans																							$ 21,000,000
Bonds \| PNM 2021 Fixed Rate PCRBs \| Subsequent event
Debt Instrument [Line Items]
Stated interest rate													0.875%
Bonds \| Pollution Control Revenue Bonds at 6.25% \| Maricopa County, Arizona Pollution Control Corporation
Debt Instrument [Line Items]
Stated interest rate																				6.25%			6.25%
Aggregate principal amount																				$ 36,000,000			$ 36,000,000
Debt instrument, redemption price, percentage									101.00%
Bonds \| Pollution Control Revenue Bonds at 6.25% \| City of Farmington, New Mexico
Debt Instrument [Line Items]
Stated interest rate																				6.25%			6.25%
Aggregate principal amount																				$ 11,500,000			$ 11,500,000
Bonds \| Pollution Control Revenue Bonds at 5.90% \| City of Farmington, New Mexico
Debt Instrument [Line Items]
Stated interest rate																				5.90%			5.90%
Aggregate principal amount																				$ 255,000,000			$ 255,000,000
Bonds \| PNM \| PNM 2021 75 Million Term Loan
Debt Instrument [Line Items]
Variable interest rate										0.91%
Mortgage Bonds \| Texas-New Mexico Power Company \| TNMP 2021 Bond Purchase Agreement
Debt Instrument [Line Items]
Stated interest rate															2.44%
Aggregate principal amount															$ 65,000,000
Debt instrument, series of bond issuance \| bond_series															1
Mortgage Bonds \| Texas-New Mexico Power Company \| TNMP 2020 Bond Purchase Agreement
Debt Instrument [Line Items]
Aggregate principal amount																						$ 185,000,000
Debt instrument, series of bond issuance \| bond_series																						4
Mortgage Bonds \| Texas-New Mexico Power Company \| TNMP 2020 Bond Purchase Agreement, Bond Series 1 and 2
Debt Instrument [Line Items]
Aggregate principal amount																						$ 110,000,000
Mortgage Bonds \| Texas-New Mexico Power Company \| TNMP 2020 Bond Purchase Agreement, Bond Series 3 and 4
Debt Instrument [Line Items]
Aggregate principal amount																			$ 75,000,000
Mortgage Bonds \| 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%
Senior Notes \| PNM 2021 SUNs at 2.59% due July 15, 2033
Debt Instrument [Line Items]
Stated interest rate	2.59%
Aggregate principal amount	$ 80,000,000
Senior Notes \| PNM 2021 SUNs at 3.14% due July 15, 2041
Debt Instrument [Line Items]
Stated interest rate	3.14%
Aggregate principal amount	$ 80,000,000
Senior Notes \| PNM SUNs at 5.35% due October 1, 2021
Debt Instrument [Line Items]
Stated interest rate	5.35%
Repayments of debt	$ 160,000,000
Senior Notes \| Senior Unsecured Notes, 3.21% Series A, due April 2030
Debt Instrument [Line Items]
Stated interest rate							3.21%
Aggregate principal amount							$ 150,000,000
Senior Notes \| Senior Unsecured Notes, 3.57% Series B, due April 2039
Debt Instrument [Line Items]
Stated interest rate							3.57%
Aggregate principal amount							$ 50,000,000
Senior Notes \| Two Point Two Nine Percent Senior Unsecured Notes Due July 15, 2033
Debt Instrument [Line Items]
Stated interest rate														2.29%
Aggregate principal amount														$ 50,000,000
Senior Notes \| Two Point Nine Seven Senior Unsecured Notes Due July 15, 2041
Debt Instrument [Line Items]
Stated interest rate														2.97%
Aggregate principal amount														$ 100,000,000
Senior Notes \| PNM
Debt Instrument [Line Items]
Aggregate principal amount							200,000,000
Senior Notes \| PNM \| PNM 2021 Note Purchase Agreement
Debt Instrument [Line Items]
Aggregate principal amount	$ 160,000,000
Debt instrument, series of bond issuance \| bond_series	2
Senior Notes \| PNM \| PNM 2020 250 Million Term Loan
Debt Instrument [Line Items]
Repayments of debt							100,000,000
Proceeds from issuance of debt							$ 100,000,000
Senior Notes \| PNM \| PNM September 2021 Note Purchase Agreement
Debt Instrument [Line Items]
Aggregate principal amount														$ 150,000,000
Debt instrument, series of bond issuance \| bond_series														2
Term loan agreement with banks \| PNM \| PNM 2021 75 Million Term Loan
Debt Instrument [Line Items]
Aggregate principal amount		$ 75,000,000
Variable interest rate										0.91%
Medium-term Notes \| PNMR Development Term Loan
Debt Instrument [Line Items]
Repayments of debt			$ 65,000,000
Medium-term Notes \| PNM \| PNM 2020 250 Million Term Loan
Debt Instrument [Line Items]
Aggregate principal amount								$ 250,000,000									$ 150,000,000
Medium-term Notes \| PNM \| PNM 2019 Term Loan
Debt Instrument [Line Items]
Repayments of debt								$ 250,000,000
Letter of credit \| WFB LOC Facility
Debt Instrument [Line Items]
Aggregate principal amount																		$ 30,300,000
Unsecured Debt \| PNMR 2018 SUNS 3.25% due March 2021
Debt Instrument [Line Items]
Stated interest rate																								3.25%
Aggregate principal amount																								$ 300,000,000
Repayments of debt				$ 80,000,000