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Regulatory and Rate Matters - Advanced Metering Infrastructure Application and Facebook Data Center Project (Details) $ in Millions |  | 3 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Aug. 24, 2018 Facility power_purchase_agreement MW | Dec. 31, 2017 MW | Dec. 31, 2019 MW | Sep. 05, 2017 MW | Aug. 17, 2016 service_rate | Feb. 26, 2016 USD ($)
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Number of requested service rates | service_rate |  |  |  |  | 2 |
Ownership percentage |  |  | 50.00% |  |  |
Facebook Data Center |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
PPA term |  | 25 years |  |  |  |
Number of additional PPAs | power_purchase_agreement | 2 |  |  |  |  |
Public Service Company of New Mexico | Advanced metering infrastructure |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Application to seek recovery of costs of project | $ |  |  |  |  |  | $ 87.2
Adjustment to estimated costs to be recovered | $ |  |  |  |  |  | 95.1
Application to seek recovery of undepreciated investment | $ |  |  |  |  |  | $ 33.0
PNMR Development |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Solar distributed generation (in mw) |  |  | 80 | 50 |  |
Ownership percentage |  |  | 50.00% |  |  |
Casa Mesa Wind, LLC | Facebook Data Center |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Solar distributed generation (in mw) |  | 50 |  |  |  |
Avangrid Renewables, LLC | Facebook Data Center |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Solar distributed generation (in mw) |  | 166 |  |  |  |
Route 66 Solar Energy Center, LLC | Facebook Data Center |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Solar distributed generation (in mw) | 100 | 50 |  |  |  |
Number of solar facilities | Facility | 2 |  |  |  |  |

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