Number Of Regulated Utilities

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- Definition

Amount of allowance for credit loss on accounts receivable.

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- Definition

Amount of increase (decrease) in allowance for credit loss on accounts receivable.

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- Definition

Carrying amount as of the balance sheet date of the asset arising from commodity contracts such as futures contracts tied to the movement of a particular commodity, which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer.

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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- Definition

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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Electric Operating Revenues - Narrative (Details)	3 Months Ended
Electric Operating Revenues - Narrative (Details)	Mar. 31, 2021 USD ($) utility	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Disaggregation of Revenue [Line Items]
Number of regulated utilities \| utility	2
Accounts receivable, allowance for credit loss, period increase (decrease)	$ 1,600,000	$ 300,000
Contract assets	0		$ 0
Texas-New Mexico Power Company
Disaggregation of Revenue [Line Items]
Accounts receivable, allowance for credit loss	1,400,000
PNM
Disaggregation of Revenue [Line Items]
Accounts receivable	$ 73,200,000		$ 86,200,000