For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Publisher FASB
-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Segment Information - Major Customers (Details) - Customer Concentration Risk - Electric operating revenues	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Customer One
Concentration Risk [Line Items]
Concentration risk	24.00%	11.00%
Texas-New Mexico Power Company \| REP A
Concentration Risk [Line Items]
Concentration risk	27.00%	23.00%	21.00%
Texas-New Mexico Power Company \| REP B
Concentration Risk [Line Items]
Concentration risk	20.00%	19.00%	18.00%
Texas-New Mexico Power Company \| REP C
Concentration Risk [Line Items]
Concentration risk		10.00%	11.00%