Debt Instrument, Covenant, Debt To Capitalization Ratio

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- Definition

Debt Instrument, Covenant, Debt-to-Capital Ratio

+ References

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- Definition

Debt Instrument, Number of Loans

+ References

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- Definition

Debt Instrument, Prepayment Period

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- Definition

Debt Instrument, Series Of Bond Issuance

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- Definition

Debt Instrument, Shelf Registration Statement for Unsecured Debt

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No definition available.

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- Definition

Payments To Fund Long-term Loans To Unaffiliated Third Party

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- Definition

Public Utilities, Maturity term over which financings require regulator approval

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- Definition

Public Utilities, Request Issuance Of Energy Transition Bonds

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- Definition

Term Loan Restatement Committed Amount

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- Definition

Term Loan Restatement To Provide Additional Funding

+ References

No definition available.

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

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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

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

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Percentage of principal amount of debt redeemed.

+ References

No definition available.

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

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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

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- Definition

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

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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- Definition

Amount of interest income earned from interest-bearing assets owed to the entity by related party.

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No definition available.

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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

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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, 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.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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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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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

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Amount of transactions with related party during the financial reporting period.

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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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Cash received on stock transaction after deduction of issuance costs.

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No definition available.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Financing - Financing Activities (Details)																								1 Months Ended	12 Months Ended
Financing - Financing Activities (Details)	Dec. 21, 2020 USD ($)	Dec. 15, 2020 USD ($) $ / shares shares	Oct. 20, 2020 USD ($)	Jun. 22, 2020 USD ($)	Apr. 30, 2020 USD ($)	Apr. 24, 2020 USD ($) bond_series	Apr. 15, 2020 USD ($)	Apr. 01, 2020 USD ($)	Jan. 08, 2020 shares	Jan. 07, 2020 $ / shares shares	Jan. 01, 2020	Dec. 13, 2019	Jul. 01, 2019 USD ($)	Apr. 01, 2019 USD ($)	Feb. 26, 2019 USD ($)	Dec. 21, 2018 USD ($)	Dec. 14, 2018 USD ($)	Jul. 31, 2018 USD ($)	May 14, 2018 USD ($)	Apr. 09, 2018 USD ($)	Mar. 09, 2018 USD ($)	Jan. 01, 2018 USD ($) loan	Jul. 28, 2017 USD ($) bond_series	Dec. 31, 2018 USD ($) derivative	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($) derivative	Feb. 19, 2021 USD ($)	Dec. 22, 2020 USD ($)	Nov. 26, 2020 USD ($)	Nov. 25, 2020 USD ($)	Jul. 15, 2020 USD ($)	Jun. 30, 2020 USD ($)	Jun. 01, 2020 USD ($)	Dec. 18, 2019 USD ($)	Jul. 22, 2019 USD ($)	Mar. 29, 2019 USD ($)	Jan. 18, 2019 USD ($)	Dec. 17, 2018 USD ($)	Nov. 26, 2018 USD ($)	Jul. 25, 2018 USD ($)	Jun. 28, 2018 USD ($)	May 22, 2018 USD ($)
Debt Instrument [Line Items]
Short-term debt																									$ 32,000,000	$ 185,100,000
Common stock, shares issued (in shares) \| shares																									85,834,874	85,834,874
Financing capacity																									$ 40,000,000.0											$ 50,000,000.0
Interest expenses																									114,392,000	$ 121,016,000	$ 127,244,000
Fixed interest rate																						1.927%
Cash Flow Hedge \| Significant Other Observable Inputs (Level 2)
Debt Instrument [Line Items]
Fair value gain (loss, less than)																									900,000	400,000
Interest rate contract
Debt Instrument [Line Items]
Number of derivatives \| derivative																								3			3
Revolving Credit Facility \| Subsequent Event
Debt Instrument [Line Items]
Available borrowing capacity																												$ 773,100,000
PNMR 2020 Forward Equity Sales Agreement
Debt Instrument [Line Items]
Common stock, shares issued (in shares) \| shares										6,200,000
Number of shares issued in transaction (in shares) \| shares		6,200,000
Sale of stock, price per share (in dollars per share) \| $ / shares		$ 45.805								$ 47.21
Sale of stock, consideration received on transaction		$ 283,100,000
Payments of stock issuance costs		$ 100,000
Over-Allotment Option
Debt Instrument [Line Items]
Number of shares issued in transaction (in shares) \| shares									800,000	800,000
PNMR 2015 Term Loan
Debt Instrument [Line Items]
Term loans																					$ 150,000,000.0	$ 150,000,000.0
PNMR 2016 One-Year Term Loan and PNMR 2016 Two-Year Term Loan
Debt Instrument [Line Items]
Number of loan agreements (in loans) \| loan																						2
PNMR 2016 One Year Term Loan
Debt Instrument [Line Items]
Short-term debt																						$ 100,000,000.0
Debt instrument, term																	1 year					1 year		1 year
PNMR 2016 Two-Year Term Loan
Debt Instrument [Line Items]
Term loans																						$ 100,000,000.0
Debt instrument, term																2 years	2 years					2 years		2 years
PNMR 2020 Delayed-Draw Term Loan
Debt Instrument [Line Items]
Term loans																									$ 80,000,000.0				$ 300,000,000.0
Variable interest rate																									1.40%
PNMR Development Term Loan due January 2022
Debt Instrument [Line Items]
Variable interest rate																									1.52%
PNMR 2018 One Year Term Loan
Debt Instrument [Line Items]
Aggregate principal amount																	$ 150,000,000.0
Debt instrument, term												1 year					1 year
Variable interest rate																									1.11%
PNMR 2018 Two-Year Term Loan due December 2020
Debt Instrument [Line Items]
Term loans	$ 50,000,000.0
Aggregate principal amount																$ 50,000,000.0
Debt instrument, term	2 years															2 years
PNMR 2020 Term Loan
Debt Instrument [Line Items]
Term loans	$ 150,000,000.0
Variable interest rate	1.25%
TNMP 2018 Term Loan due July 2020
Debt Instrument [Line Items]
Term loan restatement to provide additional funding																																							$ 15,000,000.0
Term loan restatement committed amount																																							$ 35,000,000.0
Variable Rate Short-Term Debt
Debt Instrument [Line Items]
Aggregate principal amount																								$ 50,000,000.0			$ 50,000,000.0
Term of derivatives																									4 years
Variable Rate Short-Term Debt \| Interest rate 1
Debt Instrument [Line Items]
Fixed interest rate																								1.926%			1.926%
Variable Rate Short-Term Debt \| Interest rate 2
Debt Instrument [Line Items]
Fixed interest rate																								1.823%			1.823%
Variable Rate Short-Term Debt \| Interest rate 3
Debt Instrument [Line Items]
Fixed interest rate																								1.629%			1.629%
Maximum
Debt Instrument [Line Items]
Short-term debt - affiliate																									$ 150,000,000.0
PNM and TNMP
Debt Instrument [Line Items]
Short-term debt - affiliate																									0	0
PNM and TNMP \| Subsequent Event
Debt Instrument [Line Items]
Short-term debt - affiliate																												0
PNM
Debt Instrument [Line Items]
Short-term debt																									$ 10,000,000	$ 58,000,000
Common stock, shares issued (in shares) \| shares																									39,117,799	39,117,799
Interest expenses																									$ 64,615,000	$ 72,900,000	$ 76,458,000
PNM \| PNM 2019 $250.0 Million Term Loan due July 2020
Debt Instrument [Line Items]
Aggregate principal amount																																						$ 250,000,000.0
PNM \| PNM 2019 $40.0 Million Term Loan due June 2021
Debt Instrument [Line Items]
Aggregate principal amount																																			$ 40,000,000.0
PNM \| Maximum
Debt Instrument [Line Items]
Maturity term over which financings require regulator approval (more than)																									18 months
NM Capital \| BTMU Term Loan
Debt Instrument [Line Items]
Term loans																						$ 125,000,000.0
Estimated principal payments																																											$ 43,000,000.0
PNMR \| PNMR 3.25% 2018 SUNs due March 2021
Debt Instrument [Line Items]
Term loans																									$ 300,000,000	300,000,000
Stated percentage																									3.25%
PNMR \| PNMR 2020 Delayed-Draw Term Loan
Debt Instrument [Line Items]
Term loans																									$ 80,000,000	0
Available borrowing capacity																					220,000,000.0
Repayments of debt																					220,000,000.0
PNMR \| PNMR Development Term Loan due January 2022
Debt Instrument [Line Items]
Term loans																									65,000,000	90,000,000
PNMR \| PNMR 2018 Two-Year Term Loan due December 2020
Debt Instrument [Line Items]
Term loans																									0	50,000,000
PNMR \| Merger Backstop Facilities \| Term Loan
Debt Instrument [Line Items]
Debt instrument, term			364 days
Financing capacity			$ 50,000,000.0
PNMR \| Merger Backstop Facilities \| Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Debt instrument, term			364 days
Financing capacity			$ 300,000,000.0
PNMR \| PNMR 2020 Term Loan
Debt Instrument [Line Items]
Term loans																									150,000,000	0
PNMR \| PNM 2019 Term Loan
Debt Instrument [Line Items]
Term loans																									150,000,000	150,000,000
Texas-New Mexico Power Company
Debt Instrument [Line Items]
Short-term debt																									$ 0	$ 15,000,000
Common stock, shares issued (in shares) \| shares																									6,358	6,358
Interest expenses																									$ 30,388,000	$ 29,100,000	32,091,000
PNMR Development
Debt Instrument [Line Items]
Short-term debt - affiliate																									$ 300,000	0
PNMR Development \| Deposit Related to Potential Transmission Interconnections
Debt Instrument [Line Items]
Amount of related party transaction																				$ 68,200,000
Accrued interest																				$ 5,700,000
Interest expenses																										3,300,000	$ 2,400,000
PNMR Development \| Subsequent Event
Debt Instrument [Line Items]
Short-term debt - affiliate																												$ 400,000
Line of Credit
Debt Instrument [Line Items]
Ratio of debt to capital (less than or equal to)																									65.00%
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%
Line of Credit \| PNM \| PNM Revolving Credit Facility
Debt Instrument [Line Items]
Repayments of debt					$ 100,000,000.0
Letter of Credit \| PNMR \| Letter or credit, 30 mil JP Morgan
Debt Instrument [Line Items]
Aggregate principal amount																						30,300,000
Senior Unsecured Notes \| PNMR 3.25% 2018 SUNs due March 2021
Debt Instrument [Line Items]
Term loans																					220,000,000.0
Aggregate principal amount																					$ 300,000,000.0
Stated percentage																					3.25%
Senior Unsecured Notes \| PNM
Debt Instrument [Line Items]
Shelf registration statement, capacity of issuance (up to)																									$ 650,000,000.0
Senior Unsecured Notes \| PNM \| Senior Unsecured Note Agreement (SUNs), Private Placement Transactions with Institutional Investors
Debt Instrument [Line Items]
Aggregate principal amount																							$ 450,000,000.0
Series of bond issuance \| bond_series																							8
Debt to capital ratio																							65.00%
Senior Unsecured Notes \| PNM \| SUNs, Private Placement Transaction with Institutional Investors, Issuance in May 2018
Debt Instrument [Line Items]
Aggregate principal amount																			$ 350,000,000.0
Senior Unsecured Notes \| PNM \| SUNs at 7.95% due 2018
Debt Instrument [Line Items]
Stated percentage																			7.95%
Senior Unsecured Notes \| PNM \| SUN's, Private Placement Transaction with Institutional Investors, Issuance in July 2018
Debt Instrument [Line Items]
Aggregate principal amount																		$ 100,000,000.0
Senior Unsecured Notes \| PNM \| SUNs at 7.50% due August 2018
Debt Instrument [Line Items]
Stated percentage																		7.50%
Senior Unsecured Notes \| PNM \| PNM 2019 $250.0 Million Term Loan due July 2020
Debt Instrument [Line Items]
Term loans																									0	250,000,000.0
Senior Unsecured Notes \| PNM \| PNM 2019 $40.0 Million Term Loan due June 2021
Debt Instrument [Line Items]
Term loans																									$ 40,000,000	40,000,000
Senior Unsecured Notes \| PNM \| Minimum \| SUNs, Private Placement Transaction with Institutional Investors, Issuance in May 2018
Debt Instrument [Line Items]
Debt instrument, term																			5 years
Stated percentage																			3.15%
Senior Unsecured Notes \| PNM \| Minimum \| SUN's, Private Placement Transaction with Institutional Investors, Issuance in July 2018
Debt Instrument [Line Items]
Debt instrument, term																		10 years
Stated percentage																		3.78%
Senior Unsecured Notes \| PNM \| Maximum \| SUNs, Private Placement Transaction with Institutional Investors, Issuance in May 2018
Debt Instrument [Line Items]
Debt instrument, term																			30 years
Stated percentage																			4.50%
Senior Unsecured Notes \| PNM \| Maximum \| SUN's, Private Placement Transaction with Institutional Investors, Issuance in July 2018
Debt Instrument [Line Items]
Debt instrument, term																		30 years
Stated percentage																		4.60%
Senior Unsecured Notes \| Texas-New Mexico Power Company \| First Mortgage Bonds at 9.50% due 2019
Debt Instrument [Line Items]
Stated percentage														9.50%
Extinguishment of debt														$ 172,300,000
Medium-term Notes \| PNMR Development Term Loan due January 2022
Debt Instrument [Line Items]
Aggregate principal amount																														$ 65,000,000.0	$ 90,000,000.0									$ 90,000,000.0
Medium-term Notes \| PNM \| PNM 2020 $250.0 Million Term Loan
Debt Instrument [Line Items]
Aggregate principal amount	$ 150,000,000.0						$ 250,000,000.0
Medium-term Notes \| PNM \| PNM 2019 Term Loan
Debt Instrument [Line Items]
Repayments of debt							$ 250,000,000.0
Notes Payable to Banks \| PNM \| PNM 2017 Term Loan Agreement \| JPMorgan Chase Bank, N.A. and U.S. Bank National Association
Debt Instrument [Line Items]
Aggregate principal amount																						200,000,000.0
Notes Payable to Banks \| PNM \| PNM 2019 $40.0 Million Term Loan due June 2021 \| JPMorgan Chase Bank, N.A. and U.S. Bank National Association
Debt Instrument [Line Items]
Stated percentage																									0.80%
Secured Debt \| Texas-New Mexico Power Company \| TNMP First Mortgage Bonds
Debt Instrument [Line Items]
Aggregate principal amount																									$ 750,000,000.0
Debt instrument, prepayment period																									30 days
Debt instrument, redemption price, percentage of principal amount redeemed																									100.00%
Secured Debt \| Texas-New Mexico Power Company \| TNMP Term Loan Agreement
Debt Instrument [Line Items]
Aggregate principal amount																																									$ 20,000,000.0
Secured Debt \| Texas-New Mexico Power Company \| TNMP 2020 Bond Purchase Agreement
Debt Instrument [Line Items]
Ratio of debt to capital (less than or equal to)						65.00%
Aggregate principal amount						$ 185,000,000.0
Series of bond issuance \| bond_series						4
Secured Debt \| Texas-New Mexico Power Company \| TNMP 2020 Bond Purchase Agreement, Bond Series 1 and 2
Debt Instrument [Line Items]
Aggregate principal amount						$ 110,000,000.0
Secured Debt \| Texas-New Mexico Power Company \| TNMP 2020 Bond Purchase Agreement, Bond Series 3 and 4
Debt Instrument [Line Items]
Aggregate principal amount																																$ 75,000,000.0
Senior Notes \| Senior Unsecured Notes, 3.21% Series A, due April 2030
Debt Instrument [Line Items]
Aggregate principal amount					$ 150,000,000.0
Stated percentage					3.21%
Senior Notes \| Senior Unsecured Notes, 3.57% Series B, due April 2039
Debt Instrument [Line Items]
Aggregate principal amount					$ 50,000,000.0
Stated percentage					3.57%
Senior Notes \| PNM
Debt Instrument [Line Items]
Ratio of debt to capital (less than or equal to)					65.00%
Aggregate principal amount					$ 200,000,000.0
Senior Notes \| PNM \| PNM 2020 $250.0 Million Term Loan
Debt Instrument [Line Items]
Repayments of debt					$ 100,000,000.0
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
Debt Instrument [Line Items]
Term loans																										100,300,000
Aggregate principal amount																																	$ 100,300,000
Stated percentage																									0.19%
Bonds \| Pollution Control Revenue Bonds, Due 2040
Debt Instrument [Line Items]
Term loans																										40,000,000.0
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																										21,000,000.0
Bonds \| Pollution Control Revenue Bonds, 6.25%, Callable \| Maricopa County, Arizona Pollution Control Corporation
Debt Instrument [Line Items]
Aggregate principal amount																										$ 36,000,000.0
Stated percentage																										6.25%
Debt instrument, redemption price, percentage											101.00%
Bonds \| Pollution Control Revenue Bonds, 6.25%, Callable \| City of Farmington, New Mexico
Debt Instrument [Line Items]
Aggregate principal amount																										$ 11,500,000
Stated percentage																										6.25%
Bonds \| Pollution Control Revenue Bonds, 5.90%, Callable \| City of Farmington, New Mexico
Debt Instrument [Line Items]
Aggregate principal amount																										$ 255,000,000.0
Stated percentage																										5.90%
Mortgages \| Texas-New Mexico Power Company \| First Mortgage Bonds
Debt Instrument [Line Items]
Aggregate principal amount																																										$ 60,000,000.0
Stated percentage																																										3.85%
Mortgages \| Texas-New Mexico Power Company \| TNMP 2019 Bond Purchase Agreement
Debt Instrument [Line Items]
Aggregate principal amount															$ 305,000,000.0																						$ 225,000,000.0
Stated percentage															400.00%
Debt to capital ratio															65.00%
Mortgages \| Texas-New Mexico Power Company \| First Mortgage Bonds at 3.60% due 2029
Debt Instrument [Line Items]
Aggregate principal amount													$ 80,000,000.0
San Juan Coal Company, Westmoreland \| NM Capital \| Coal Supply
Debt Instrument [Line Items]
Term loans																						50,100,000
Repurchased face amount																																											$ 50,100,000
San Juan Generating Station \| PNM
Debt Instrument [Line Items]
Request issuance of energy transition bonds								$ 361,000,000					$ 361,000,000
San Juan Generating Station \| NM Capital \| Coal Supply
Debt Instrument [Line Items]
Payments to fund long-term loans to unaffiliated third party																						$ 125,000,000.0