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Public Utilities, Number Of Replacement Resource Scenarios

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Public Utilities, Plant Decommissioning And Coal Mine Reclamation Costs

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Public Utilities, Renewable Energy, Percentage

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Regulated Operations, Required Percentage of Renewable Energy in Portfolio to Electric Sales

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Public Utilities, Solar generation capacity in Megawatts

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Public Utilities, Solar Generation Capacity, Power Purchase Agreement, in Megawatts

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Public Utilities, Upfront Financing Costs

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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.

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Regulatory and Rate Matters - SJGS Abandonment Application (Details) $ in Millions	Apr. 01, 2020 USD ($)	Jul. 01, 2019 USD ($) scenario MW	May 31, 2019 MW	Mar. 31, 2020 USD ($) MW	Mar. 27, 2020 MMBTU MW	Feb. 21, 2020 USD ($)	Jun. 14, 2019
PNM Solar Direct
Public Utilities, General Disclosures [Line Items]
Solar generation capacity (in megawatts) \| MW			50
Power purchase agreement term			15 years
Required Percentage by 2020 \| Energy Transition Act \| Electric-Generation Portfolio Standard
Public Utilities, General Disclosures [Line Items]
Renewable energy, percentage							0.20
Required Percentage by 2025 \| Energy Transition Act \| Electric-Generation Portfolio Standard
Public Utilities, General Disclosures [Line Items]
Renewable energy, percentage							0.40
Required Percentage by 2030 \| Energy Transition Act \| Electric-Generation Portfolio Standard
Public Utilities, General Disclosures [Line Items]
Renewable energy, percentage							0.50
Required Percentage by 2040 \| Energy Transition Act \| Electric-Generation Portfolio Standard
Public Utilities, General Disclosures [Line Items]
Renewable energy, percentage							0.80
Required Percentage by 2045 \| Energy Transition Act \| Electric-Generation Portfolio Standard
Public Utilities, General Disclosures [Line Items]
Renewable energy, percentage							1
PNM
Public Utilities, General Disclosures [Line Items]
Number of megawatts in battery storage facilities (in megawatts) \| MW					40
Solar generation capacity (in megawatts) \| MW					300
Solar generation capacity, power purchase agreements (in Megawatts) \| MMBTU					20
PNM \| Renewable Portfolio Standard
Public Utilities, General Disclosures [Line Items]
Solar generation capacity (in megawatts) \| MW				133.0
PNM \| PNM Solar Direct
Public Utilities, General Disclosures [Line Items]
Solar generation capacity (in megawatts) \| MW					50
PNM \| Required Percentage by 2011 \| Renewable Portfolio Standard
Public Utilities, General Disclosures [Line Items]
Required percentage of renewable energy in portfolio to electric sales				10.00%
PNM \| Required Percentage by 2015 \| Renewable Portfolio Standard
Public Utilities, General Disclosures [Line Items]
Required percentage of renewable energy in portfolio to electric sales				15.00%
PNM \| Required Percentage by 2020 \| Renewable Portfolio Standard
Public Utilities, General Disclosures [Line Items]
Required percentage of renewable energy in portfolio to electric sales				20.00%
San Juan Generating Station \| Other deferred credits
Public Utilities, General Disclosures [Line Items]
Restructuring reserve				$ 38.1
San Juan Generating Station \| Employee Severance
Public Utilities, General Disclosures [Line Items]
Restructuring reserve				9.4
San Juan Generating Station \| PNM
Public Utilities, General Disclosures [Line Items]
Number of megawatts in natural gas-fired peaking plant (in megawatts) \| MW		280
Number of megawatts in battery storage facilities (in megawatts) \| MW		70
Solar generation capacity (in megawatts) \| MW		350
Number of megawatts in battery storage facilities, replacement resource scenario (in megawatts) \| MW		60
Number of replacement resource scenarios \| scenario		3
Request issuance of energy transition bonds		$ 361.0
Forecasted undepreciated investment		283.0				$ 361.0
Plant decommissioning and coal mine reclamation costs		28.6
Upfront financing costs		9.6
Severance costs		20.0
Proceeds from securitization bonds		$ 19.8
San Juan Generating Station \| PNM \| Other deferred credits
Public Utilities, General Disclosures [Line Items]
Restructuring reserve				36.8
San Juan Generating Station \| PNM \| Employee Severance
Public Utilities, General Disclosures [Line Items]
Restructuring reserve				8.1
San Juan Generating Station \| PNM \| Other Restructuring
Public Utilities, General Disclosures [Line Items]
Restructuring reserve				8.9
San Juan Generating Station \| PNM \| Economic Development and Workforce Training Costs
Public Utilities, General Disclosures [Line Items]
Restructuring reserve				$ 19.8
Subsequent event \| San Juan Generating Station \| PNM
Public Utilities, General Disclosures [Line Items]
Request issuance of energy transition bonds	$ 361.0