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Regulatory and Rate Matters - Advanced Metering Infrastructure Application and Facebook Data Center Project (Details) $ in Millions | 3 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2017 MW | May 12, 2017 USD ($) | Jul. 08, 2016 service_rate MW | Feb. 26, 2016 USD ($)
Public Utilities, General Disclosures [Line Items] |  |  |  |
Number of requested service rates | service_rate |  |  | 2 |
Facebook Data Center |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |
PPA term | 25 years |  |  |
Public Service Company of New Mexico | Advanced metering infrastructure |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |
Application to seek recovery of costs of project | $ |  | $ 95.1 |  | $ 87.2
Application to seek recovery of undepreciated investment | $ |  |  |  | $ 33.0
PNMR Development |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |
Solar distributed generation (in mw) |  |  | 30 |
Solar capacity (in mw) |  |  | 10 |
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) | 50 |  |  |

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