Commitments and Contingencies Texas Fuel Reconciliation (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
Alternative Energy [Member] \| NMPRC [Member] \| SPS
Public Utilities, General Disclosures [Line Items]
Fuel Costs Disallowed	$ 6

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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