v3.25.2
SEGMENT INFORMATION - Narrative (Details)
$ in Millions
6 Months Ended
Jun. 30, 2025
USD ($)
reportableSegment
CL&P  
Segment Reporting Information [Line Items]  
Number of reportable segment 1
NSTAR Electric  
Segment Reporting Information [Line Items]  
Number of reportable segment 1
PSNH  
Segment Reporting Information [Line Items]  
Number of reportable segment 1
Related Party  
Segment Reporting Information [Line Items]  
Amount of natural gas transmission purchased | $ $ 77.7