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REVENUES (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | $ 2,515,300 | $ 2,625,600 | $ 5,792,100 | $ 6,377,500
Alternative Revenue Programs | 13,500 | (2,700) | 62,600 | 34,200
Other Revenues | 4,700 | 6,400 | 11,400 | 13,300
Operating Revenues | 2,533,522 | 2,629,342 | 5,866,097 | 6,424,985
CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating Revenues | 964,623 | 1,034,148 | 2,085,914 | 2,373,054
NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating Revenues | 845,068 | 818,968 | 1,792,683 | 1,775,251
PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating Revenues | 287,311 | 350,070 | 613,427 | 770,225
Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 2,206,300 | 2,341,700 | 5,110,700 | 5,688,800
Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,269,400 | 1,379,500 | 3,061,300 | 3,449,000
Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 816,300 | 839,000 | 1,785,300 | 1,961,900
Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 120,600 | 123,200 | 264,100 | 277,900
Wholesale Transmission Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 116,800 | 99,200 | 229,300 | 209,000
Wholesale Market Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 168,000 | 153,100 | 392,500 | 420,300
Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 24,200 | 31,600 | 59,600 | 59,400
Operating Segments | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,112,000 | 1,124,200 | 2,362,900 | 2,576,000
Alternative Revenue Programs | 23,900 | 52,600 | 51,300 | 77,300
Other Revenues | 1,500 | 2,500 | 4,300 | 4,700
Operating Segments | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,006,000 | 961,100 | 2,103,100 | 2,065,500
Alternative Revenue Programs | 4,200 | (5,000) | 12,000 | (14,500)
Other Revenues | 1,600 | 1,800 | 3,600 | 4,300
Operating Segments | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 348,100 | 375,600 | 722,000 | 836,700
Alternative Revenue Programs | 3,400 | 21,900 | 11,000 | 31,500
Other Revenues | 600 | 700 | 1,400 | 1,700
Operating Segments | Total Retail Tariff Sales Revenues | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 794,300 | 880,000 | 1,706,800 | 1,971,400
Operating Segments | Total Retail Tariff Sales Revenues | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 764,800 | 748,800 | 1,630,400 | 1,633,600
Operating Segments | Total Retail Tariff Sales Revenues | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 241,800 | 290,700 | 513,400 | 655,900
Operating Segments | Residential | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 513,700 | 593,700 | 1,140,600 | 1,355,900
Operating Segments | Residential | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 380,200 | 370,500 | 842,400 | 838,300
Operating Segments | Residential | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 133,600 | 178,000 | 298,600 | 412,000
Operating Segments | Commercial | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 248,000 | 255,000 | 500,400 | 550,300
Operating Segments | Commercial | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 354,400 | 347,200 | 727,900 | 731,500
Operating Segments | Commercial | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 81,100 | 90,200 | 163,100 | 198,800
Operating Segments | Industrial | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 32,600 | 31,300 | 65,800 | 65,200
Operating Segments | Industrial | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 30,200 | 31,100 | 60,100 | 63,800
Operating Segments | Industrial | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 27,100 | 22,500 | 51,700 | 45,100
Operating Segments | Wholesale Transmission Revenues | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 218,800 | 172,500 | 419,500 | 368,300
Operating Segments | Wholesale Transmission Revenues | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 200,900 | 166,900 | 389,700 | 334,700
Operating Segments | Wholesale Transmission Revenues | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 93,200 | 63,600 | 177,800 | 135,100
Operating Segments | Wholesale Market Sales Revenues | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 97,400 | 62,900 | 218,600 | 217,600
Operating Segments | Wholesale Market Sales Revenues | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 27,000 | 32,500 | 58,600 | 73,600
Operating Segments | Wholesale Market Sales Revenues | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 7,600 | 16,900 | 20,100 | 38,400
Operating Segments | Other Revenues from Contracts with Customers | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,500 | 8,800 | 18,000 | 18,700
Operating Segments | Other Revenues from Contracts with Customers | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 13,300 | 12,900 | 24,400 | 23,600
Operating Segments | Other Revenues from Contracts with Customers | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 5,500 | 4,400 | 10,700 | 7,300
Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 395,200 | 408,800 | 838,800 | 822,700
Alternative Revenue Programs | 0 | 0 | 0 | 0
Other Revenues | 0 | 0 | 0 | 0
Operating Revenues | 395,200 | 408,800 | 838,800 | 822,700
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 | 395,200 | 408,800 | 838,800 | 822,700
Eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (797,300) | (715,500) | (1,607,200) | (1,459,400)
Alternative Revenue Programs | (15,800) | (65,700) | (42,600) | (82,700)
Other Revenues | 0 | 0 | 0 | 0
Operating Revenues | (813,100) | (781,200) | (1,649,800) | (1,542,100)
Eliminations | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (7,500) | (5,900) | (14,300) | (12,000)
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 | (1,500) | (1,200) | (3,200) | (2,300)
Eliminations | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (6,000) | (4,700) | (11,100) | (9,700)
Eliminations | Wholesale Transmission Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (396,100) | (303,800) | (757,700) | (629,100)
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 | (393,700) | (405,800) | (835,200) | (818,300)
Consolidations Eliminations | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating Revenues | (172,800) | (145,200) | (332,600) | (284,900)
Consolidations Eliminations | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating Revenues | (166,700) | (138,900) | (326,000) | (280,000)
Consolidations Eliminations | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating Revenues | (64,800) | (48,100) | (121,000) | (99,700)
Electric Distribution | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,948,700 | 2,052,500 | 4,191,700 | 4,629,600
Alternative Revenue Programs | 14,000 | (3,000) | 27,300 | 3,100
Other Revenues | 3,600 | 4,900 | 9,000 | 10,300
Operating Revenues | 1,966,300 | 2,054,400 | 4,228,000 | 4,643,000
Electric Distribution | Operating Segments | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,800,600 | 1,919,200 | 3,849,900 | 4,260,800
Electric Distribution | Operating Segments | Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,027,500 | 1,142,200 | 2,281,600 | 2,606,200
Electric Distribution | Operating Segments | Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 683,200 | 692,100 | 1,390,700 | 1,480,500
Electric Distribution | Operating Segments | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 89,900 | 84,900 | 177,600 | 174,100
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 | 132,000 | 112,300 | 297,300 | 329,600
Electric Distribution | Operating Segments | Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 16,100 | 21,000 | 44,500 | 39,200
Natural Gas Distribution | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 392,600 | 411,100 | 1,266,400 | 1,427,900
Alternative Revenue Programs | 200 | (3,100) | 31,600 | 24,300
Other Revenues | 700 | 1,100 | 1,500 | 2,100
Operating Revenues | 393,500 | 409,100 | 1,299,500 | 1,454,300
Natural Gas Distribution | Operating Segments | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 356,100 | 370,200 | 1,170,500 | 1,336,300
Natural Gas Distribution | Operating Segments | Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 204,100 | 198,400 | 711,700 | 774,900
Natural Gas Distribution | Operating Segments | Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 116,400 | 129,900 | 363,400 | 450,000
Natural Gas Distribution | Operating Segments | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 35,600 | 41,900 | 95,400 | 111,400
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 | 35,000 | 39,800 | 93,300 | 88,900
Natural Gas Distribution | Operating Segments | Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,500 | 1,100 | 2,600 | 2,700
Electric Transmission | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 516,500 | 407,500 | 994,600 | 847,200
Alternative Revenue Programs | 17,500 | 72,500 | 47,000 | 91,200
Other Revenues | 100 | 100 | 300 | 400
Operating Revenues | 534,100 | 480,100 | 1,041,900 | 938,800
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 | 512,900 | 403,000 | 987,000 | 838,100
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 | 3,600 | 4,500 | 7,600 | 9,100
Water Distribution | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 59,600 | 61,200 | 107,800 | 109,500
Alternative Revenue Programs | (2,400) | (3,400) | (700) | (1,700)
Other Revenues | 300 | 300 | 600 | 500
Operating Revenues | 57,500 | 58,100 | 107,700 | 108,300
Water Distribution | Operating Segments | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 57,100 | 58,200 | 104,600 | 103,700
Water Distribution | Operating Segments | Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 37,800 | 38,900 | 68,000 | 67,900
Water Distribution | Operating Segments | Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 18,200 | 18,200 | 34,400 | 33,700
Water Distribution | Operating Segments | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,100 | 1,100 | 2,200 | 2,100
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 | 1,000 | 1,000 | 1,900 | 1,800
Water Distribution | Operating Segments | Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | $ 1,500 | $ 2,000 | $ 1,300 | $ 4,000

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