Debt Instrument, Covenant, Debt-to-Capital Ratio

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

Ratio of debt to capital, maximum

+ References

No definition available.

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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.

+ 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.

+ 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.

+ Details

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- Definition

Carrying amount as of the balance sheet date of unearned revenue or income, not otherwise specified in the taxonomy, which is expected to be taken into income after one year or beyond the normal operating cycle, if longer and noncurrent obligations not separately disclosed in the balance sheet (other liabilities, noncurrent).

+ References

No definition available.

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Period Type:	instant

- Definition

Variable interest rate in effect as of the balance sheet date related to the interest rate derivative.

+ References

No definition available.

+ Details

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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, 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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- Definition

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

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Financing - Financing Activities (Details) - USD ($)				3 Months Ended		6 Months Ended
Financing - Financing Activities (Details) - USD ($)	Apr. 01, 2019	Jan. 18, 2019	Apr. 09, 2018	Mar. 31, 2019	Mar. 31, 2018	Jun. 30, 2018	Jul. 01, 2019	Mar. 29, 2019	Feb. 26, 2019	Dec. 31, 2018	Jul. 25, 2018	Jul. 20, 2017	Oct. 21, 2016
Debt Instrument [Line Items]
Interest charges				$ 31,634,000	$ 33,055,000
Other deferred credits				$ 169,372,000						$ 167,668,000
PNMR 2016 Two-Year Term Loan
Debt Instrument [Line Items]
Variable interest rate				3.29%
Term loans				$ 50,000,000
Term of loan				2 years
PNM
Debt Instrument [Line Items]
Interest charges				$ 18,360,000	20,830,000
Other deferred credits				$ 215,004,000						215,737,000
PNM \| PNM 2019 Term Loan
Debt Instrument [Line Items]
Aggregate principal amount		$ 250,000,000.0
PNM \| Maximum
Debt Instrument [Line Items]
Maturity term over which financings require regulator approval (more than)				18 months
Texas-New Mexico Power Company
Debt Instrument [Line Items]
Interest charges				$ 8,800,000	$ 7,729,000
Other deferred credits				$ 3,729,000						$ 2,908,000
Texas-New Mexico Power Company \| TNMP 2019 Bond Purchase Agreement
Debt Instrument [Line Items]
Aggregate principal amount								$ 225,000,000	$ 305,000,000.0
Texas-New Mexico Power Company \| First Mortgage Bonds Due 2019, Series 2009A, at 9 point 50 percent
Debt Instrument [Line Items]
Extinguishment of debt		$ 172,300,000
Stated interest rate		9.50%
Line of credit
Debt Instrument [Line Items]
Ratio of debt to capital (less than or equal to)				65.00%		70.00%
Letter of credit \| PNMR \| JPM LOC Facility
Debt Instrument [Line Items]
Aggregate principal amount													$ 30,300,000.0
PNM 2019 Term Loan
Debt Instrument [Line Items]
Interest rate at period end				3.13%
Unsecured Debt \| Texas-New Mexico Power Company \| First Mortgage Bonds Due 2019, Series 2009A, at 9 point 50 percent
Debt Instrument [Line Items]
Extinguishment of debt	$ 172,300,000
Stated interest rate	9.50%
Mortgages \| Texas-New Mexico Power Company \| First Mortgage Bonds 3.79 Percent Due 2034
Debt Instrument [Line Items]
Aggregate principal amount								$ 75,000,000
Stated interest rate								3.79%
Mortgages \| Texas-New Mexico Power Company \| First Mortgage Bonds 3.92 Percent Due 2039
Debt Instrument [Line Items]
Aggregate principal amount								$ 75,000,000
Stated interest rate								3.92%
Mortgages \| Texas-New Mexico Power Company \| First Mortgage Bonds 4.06 Percent Due 2044
Debt Instrument [Line Items]
Aggregate principal amount								$ 75,000,000
Stated interest rate								4.06%
Mortgages \| Texas-New Mexico Power Company \| TNMP 2019 Bond Purchase Agreement
Debt Instrument [Line Items]
Aggregate principal amount				$ 305,000,000				$ 225,000,000	$ 305,000,000.0
Stated interest rate									400.00%
Debt-to-capital ratio		65.00%
Mortgages \| Texas-New Mexico Power Company \| TNMP Term Loan Agreement
Debt Instrument [Line Items]
Stated interest rate											3.20%
Mortgages \| Texas-New Mexico Power Company \| PNMR Development Term Loan
Debt Instrument [Line Items]
Stated interest rate				3.30%
Term loan agreement with banks \| PNM \| PNM 2019 Term Loan \| JPMorgan Chase Bank, N.A. and U.S. Bank National Association
Debt Instrument [Line Items]
Aggregate principal amount												$ 250,000,000
Term loan agreement with banks \| Texas-New Mexico Power Company \| TNMP Term Loan Agreement \| JPMorgan Chase Bank, N.A. and U.S. Bank National Association
Debt Instrument [Line Items]
Aggregate principal amount												$ 35,000,000
Term loan agreement with banks \| Texas-New Mexico Power Company \| PNMR Development Term Loan \| JPMorgan Chase Bank, N.A. and U.S. Bank National Association
Debt Instrument [Line Items]
Aggregate principal amount				$ 90,000,000.0
Subsequent event \| Texas-New Mexico Power Company \| First Mortgage Bonds 3.60 Percent Due 2029
Debt Instrument [Line Items]
Aggregate principal amount							$ 80,000,000
Subsequent event \| Mortgages \| Texas-New Mexico Power Company \| First Mortgage Bonds 3.60 Percent Due 2029
Debt Instrument [Line Items]
Aggregate principal amount							$ 80,000,000
Stated interest rate							3.60%
Deposit Related To Potential Transmission Interconnections \| PNMR Development
Debt Instrument [Line Items]
Amount of related party transaction			$ 68,200,000
Interest charges				900,000
Other deferred credits				$ 68,200,000