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REVENUES (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | $ 2,827,800 | $ 2,515,300 | $ 6,934,300 | $ 5,792,100
Alternative Revenue Programs | 6,400 | 13,500 | 10,900 | 62,600
Other Revenues | 3,900 | 4,700 | 11,200 | 11,400
Total Operating Revenues | 2,838,068 | 2,533,522 | 6,956,423 | 5,866,097
CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total Operating Revenues | 1,132,168 | 964,623 | 2,673,357 | 2,085,914
NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total Operating Revenues | 868,925 | 845,068 | 1,883,152 | 1,792,683
PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total Operating Revenues | 303,133 | 287,311 | 651,114 | 613,427
Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 2,436,800 | 2,206,300 | 5,947,900 | 5,110,700
Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,379,000 | 1,269,400 | 3,596,200 | 3,061,300
Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 913,000 | 816,300 | 2,039,900 | 1,785,300
Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 144,800 | 120,600 | 311,800 | 264,100
Wholesale Transmission Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 156,800 | 116,800 | 311,500 | 229,300
Wholesale Market Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 205,200 | 168,000 | 616,300 | 392,500
Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 29,000 | 24,200 | 58,600 | 59,600
Operating Segments | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,307,400 | 1,112,000 | 3,040,900 | 2,362,900
Alternative Revenue Programs | 3,200 | 23,900 | (15,700) | 51,300
Other Revenues | 100 | 1,500 | 2,800 | 4,300
Operating Segments | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,061,400 | 1,006,000 | 2,262,100 | 2,103,100
Alternative Revenue Programs | (7,900) | 4,200 | (17,000) | 12,000
Other Revenues | 2,200 | 1,600 | 4,600 | 3,600
Operating Segments | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 388,100 | 348,100 | 822,200 | 722,000
Alternative Revenue Programs | (18,800) | 3,400 | (38,500) | 11,000
Other Revenues | 600 | 600 | 1,500 | 1,400
Operating Segments | Total Retail Tariff Sales Revenues | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 937,000 | 794,300 | 2,130,800 | 1,706,800
Operating Segments | Total Retail Tariff Sales Revenues | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 790,600 | 764,800 | 1,703,300 | 1,630,400
Operating Segments | Total Retail Tariff Sales Revenues | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 251,700 | 241,800 | 546,800 | 513,400
Operating Segments | Residential | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 583,500 | 513,700 | 1,384,800 | 1,140,600
Operating Segments | Residential | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 379,600 | 380,200 | 885,700 | 842,400
Operating Segments | Residential | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 141,100 | 133,600 | 323,100 | 298,600
Operating Segments | Commercial | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 309,500 | 248,000 | 653,600 | 500,400
Operating Segments | Commercial | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 377,800 | 354,400 | 753,500 | 727,900
Operating Segments | Commercial | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 85,100 | 81,100 | 173,400 | 163,100
Operating Segments | Industrial | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 44,000 | 32,600 | 92,400 | 65,800
Operating Segments | Industrial | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 33,200 | 30,200 | 64,100 | 60,100
Operating Segments | Industrial | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 25,500 | 27,100 | 50,300 | 51,700
Operating Segments | Wholesale Transmission Revenues | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 247,100 | 218,800 | 498,200 | 419,500
Operating Segments | Wholesale Transmission Revenues | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 226,400 | 200,900 | 445,100 | 389,700
Operating Segments | Wholesale Transmission Revenues | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 122,900 | 93,200 | 247,100 | 177,800
Operating Segments | Wholesale Market Sales Revenues | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 114,700 | 97,400 | 394,700 | 218,600
Operating Segments | Wholesale Market Sales Revenues | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 32,100 | 27,000 | 89,400 | 58,600
Operating Segments | Wholesale Market Sales Revenues | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 8,400 | 7,600 | 18,800 | 20,100
Operating Segments | Other Revenues from Contracts with Customers | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 8,600 | 1,500 | 17,200 | 18,000
Operating Segments | Other Revenues from Contracts with Customers | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 12,300 | 13,300 | 24,300 | 24,400
Operating Segments | Other Revenues from Contracts with Customers | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 5,100 | 5,500 | 9,500 | 10,700
Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 405,800 | 395,200 | 844,900 | 838,800
Alternative Revenue Programs | 0 | 0 | 0 | 0
Other Revenues | 0 | 0 | 0 | 0
Total Operating Revenues | 405,800 | 395,200 | 844,900 | 838,800
Other | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 | 0 | 0
Other | Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 | 0 | 0
Other | Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 | 0 | 0
Other | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 | 0 | 0
Other | Wholesale Transmission Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 | 0 | 0
Other | Wholesale Market Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 | 0 | 0
Other | Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 405,800 | 395,200 | 844,900 | 838,800
Eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (852,900) | (797,300) | (1,735,900) | (1,607,200)
Alternative Revenue Programs | 28,200 | (15,800) | 73,400 | (42,600)
Other Revenues | 0 | 0 | 0 | 0
Total Operating Revenues | (824,700) | (813,100) | (1,662,500) | (1,649,800)
Eliminations | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (8,700) | (7,500) | (16,600) | (14,300)
Eliminations | Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 | 0 | 0
Eliminations | Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (1,900) | (1,500) | (4,000) | (3,200)
Eliminations | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (6,800) | (6,000) | (12,600) | (11,100)
Eliminations | Wholesale Transmission Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (439,600) | (396,100) | (878,900) | (757,700)
Eliminations | Wholesale Market Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 | 0 | 0
Eliminations | Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (404,600) | (393,700) | (840,400) | (835,200)
Consolidations Eliminations | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total Operating Revenues | (178,500) | (172,800) | (354,600) | (332,600)
Consolidations Eliminations | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total Operating Revenues | (186,800) | (166,700) | (366,500) | (326,000)
Consolidations Eliminations | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total Operating Revenues | (66,800) | (64,800) | (134,100) | (121,000)
Electric Distribution | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 2,156,000 | 1,948,700 | 4,925,600 | 4,191,700
Alternative Revenue Programs | 7,600 | 14,000 | 9,800 | 27,300
Other Revenues | 2,800 | 3,600 | 8,700 | 9,000
Total Operating Revenues | 2,166,400 | 1,966,300 | 4,944,100 | 4,228,000
Electric Distribution | Operating Segments | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,978,600 | 1,800,600 | 4,379,700 | 3,849,900
Electric Distribution | Operating Segments | Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,104,200 | 1,027,500 | 2,593,600 | 2,281,600
Electric Distribution | Operating Segments | Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 771,700 | 683,200 | 1,579,300 | 1,390,700
Electric Distribution | Operating Segments | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 102,700 | 89,900 | 206,800 | 177,600
Electric Distribution | Operating Segments | Wholesale Transmission Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 | 0 | 0
Electric Distribution | Operating Segments | Wholesale Market Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 155,200 | 132,000 | 502,900 | 297,300
Electric Distribution | Operating Segments | Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 22,200 | 16,100 | 43,000 | 44,500
Natural Gas Distribution | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 457,800 | 392,600 | 1,591,800 | 1,266,400
Alternative Revenue Programs | 2,300 | 200 | 8,600 | 31,600
Other Revenues | 700 | 700 | 1,700 | 1,500
Total Operating Revenues | 460,800 | 393,500 | 1,602,100 | 1,299,500
Natural Gas Distribution | Operating Segments | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 407,300 | 356,100 | 1,477,600 | 1,170,500
Natural Gas Distribution | Operating Segments | Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 234,100 | 204,100 | 930,600 | 711,700
Natural Gas Distribution | Operating Segments | Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 125,500 | 116,400 | 431,500 | 363,400
Natural Gas Distribution | Operating Segments | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 47,700 | 35,600 | 115,500 | 95,400
Natural Gas Distribution | Operating Segments | Wholesale Transmission Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 | 0 | 0
Natural Gas Distribution | Operating Segments | Wholesale Market Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 48,900 | 35,000 | 111,300 | 93,300
Natural Gas Distribution | Operating Segments | Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,600 | 1,500 | 2,900 | 2,600
Electric Transmission | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 599,700 | 516,500 | 1,197,300 | 994,600
Alternative Revenue Programs | (31,100) | 17,500 | (81,000) | 47,000
Other Revenues | 100 | 100 | 200 | 300
Total Operating Revenues | 568,700 | 534,100 | 1,116,500 | 1,041,900
Electric Transmission | Operating Segments | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 | 0 | 0
Electric Transmission | Operating Segments | Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 | 0 | 0
Electric Transmission | Operating Segments | Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 | 0 | 0
Electric Transmission | Operating Segments | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 | 0 | 0
Electric Transmission | Operating Segments | Wholesale Transmission Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 596,400 | 512,900 | 1,190,400 | 987,000
Electric Transmission | Operating Segments | Wholesale Market Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 | 0 | 0
Electric Transmission | Operating Segments | Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 3,300 | 3,600 | 6,900 | 7,600
Water Distribution | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 61,400 | 59,600 | 110,600 | 107,800
Alternative Revenue Programs | (600) | (2,400) | 100 | (700)
Other Revenues | 300 | 300 | 600 | 600
Total Operating Revenues | 61,100 | 57,500 | 111,300 | 107,700
Water Distribution | Operating Segments | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 59,600 | 57,100 | 107,200 | 104,600
Water Distribution | Operating Segments | Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 40,700 | 37,800 | 72,000 | 68,000
Water Distribution | Operating Segments | Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 17,700 | 18,200 | 33,100 | 34,400
Water Distribution | Operating Segments | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,200 | 1,100 | 2,100 | 2,200
Water Distribution | Operating Segments | Wholesale Transmission Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 | 0 | 0
Water Distribution | Operating Segments | Wholesale Market Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,100 | 1,000 | 2,100 | 1,900
Water Distribution | Operating Segments | Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | $ 700 | $ 1,500 | $ 1,300 | $ 1,300

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