XML 101 R75.htm IDEA: XBRL DOCUMENT
v3.22.1

Commitments and Contingencies - Cooling Water Intake Structures (Details) | 3 Months Ended
--- | ---
Mar. 31, 2022 option
Text Block [Abstract] |
Number of options for meeting BTA standards | 7

X
- Definition Number Of Options For Meeting BTA Standards + References No definition available. + Details
Name: | pnm_NumberOfOptionsForMeetingBTAStandards
Namespace Prefix: | pnm_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_TextBlockAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration