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REVENUES (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | $ 3,067,400 | $ 2,833,500 | $ 8,859,500 | $ 9,211,000
Alternative Revenue Programs | (10,100) | (48,200) | 52,500 | (14,000)
Other Revenues | 5,900 | 6,200 | 17,300 | 19,500
Total Operating Revenues | 3,063,224 | 2,791,482 | 8,929,321 | 9,216,467
CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total Operating Revenues | 1,345,253 | 1,190,096 | 3,431,167 | 3,563,150
NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total Operating Revenues | 1,077,523 | 953,531 | 2,870,206 | 2,728,782
PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total Operating Revenues | 342,027 | 353,074 | 955,453 | 1,123,300
Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 2,679,800 | 2,441,000 | 7,790,600 | 8,129,800
Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,595,900 | 1,503,600 | 4,657,200 | 4,952,700
Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 945,000 | 816,300 | 2,730,400 | 2,778,100
Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 138,900 | 121,100 | 403,000 | 399,000
Wholesale Transmission Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 152,500 | 133,600 | 381,800 | 342,600
Wholesale Market Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 204,000 | 227,600 | 596,400 | 647,800
Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 31,100 | 31,300 | 90,700 | 90,800
Operating Segments | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,563,600 | 1,396,200 | 3,926,400 | 3,972,200
Alternative Revenue Programs | (46,500) | (49,300) | 4,900 | 28,000
Other Revenues | 2,400 | 2,400 | 6,700 | 7,100
Operating Segments | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,236,800 | 1,129,200 | 3,339,900 | 3,194,500
Alternative Revenue Programs | 8,100 | (29,000) | 20,100 | (43,500)
Other Revenues | 2,000 | 1,900 | 5,600 | 6,300
Operating Segments | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 418,500 | 411,000 | 1,140,500 | 1,247,700
Alternative Revenue Programs | (9,700) | 900 | 1,300 | 32,400
Other Revenues | 500 | 700 | 2,000 | 2,300
Operating Segments | Total Retail Tariff Sales Revenues | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,158,200 | 1,029,300 | 2,864,900 | 3,000,700
Operating Segments | Total Retail Tariff Sales Revenues | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 980,600 | 901,800 | 2,611,100 | 2,535,400
Operating Segments | Total Retail Tariff Sales Revenues | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 296,300 | 303,800 | 809,700 | 959,700
Operating Segments | Residential | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 757,100 | 703,900 | 1,897,700 | 2,059,900
Operating Segments | Residential | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 530,800 | 480,500 | 1,373,200 | 1,318,700
Operating Segments | Residential | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 177,600 | 191,500 | 476,200 | 603,500
Operating Segments | Commercial | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 349,900 | 286,400 | 850,200 | 836,700
Operating Segments | Commercial | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 416,900 | 389,400 | 1,144,800 | 1,121,000
Operating Segments | Commercial | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 91,400 | 88,700 | 254,600 | 287,500
Operating Segments | Industrial | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 51,200 | 39,000 | 117,000 | 104,100
Operating Segments | Industrial | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 32,900 | 31,900 | 93,100 | 95,700
Operating Segments | Industrial | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 27,300 | 23,600 | 78,900 | 68,700
Operating Segments | Wholesale Transmission Revenues | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 262,200 | 245,100 | 681,700 | 613,300
Operating Segments | Wholesale Transmission Revenues | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 212,300 | 186,400 | 602,000 | 521,000
Operating Segments | Wholesale Transmission Revenues | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 109,100 | 88,700 | 286,900 | 223,900
Operating Segments | Wholesale Market Sales Revenues | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 134,100 | 112,800 | 352,800 | 330,400
Operating Segments | Wholesale Market Sales Revenues | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 31,800 | 28,600 | 90,300 | 102,100
Operating Segments | Wholesale Market Sales Revenues | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 7,900 | 13,500 | 28,000 | 51,900
Operating Segments | Other Revenues from Contracts with Customers | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 9,100 | 9,000 | 27,000 | 27,800
Operating Segments | Other Revenues from Contracts with Customers | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 12,100 | 12,400 | 36,500 | 36,000
Operating Segments | Other Revenues from Contracts with Customers | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 5,200 | 5,000 | 15,900 | 12,200
Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 414,700 | 394,700 | 1,253,600 | 1,217,300
Alternative Revenue Programs | 0 | 0 | 0 | 0
Other Revenues | 0 | 0 | 0 | 0
Total Operating Revenues | 414,700 | 394,700 | 1,253,600 | 1,217,300
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 | 414,700 | 394,700 | 1,253,600 | 1,217,300
Eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (851,600) | (784,900) | (2,458,700) | (2,244,300)
Alternative Revenue Programs | 41,000 | 31,900 | (1,700) | (50,800)
Other Revenues | 0 | 0 | 0 | 0
Total Operating Revenues | (810,600) | (753,000) | (2,460,400) | (2,295,100)
Eliminations | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (7,900) | (5,900) | (22,200) | (18,000)
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 | (2,500) | (1,100) | (5,700) | (3,400)
Eliminations | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (5,400) | (4,800) | (16,500) | (14,600)
Eliminations | Wholesale Transmission Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (431,100) | (386,600) | (1,188,800) | (1,015,600)
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 | (412,600) | (392,400) | (1,247,700) | (1,210,700)
Consolidations Eliminations | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total Operating Revenues | (174,200) | (159,200) | (506,800) | (444,100)
Consolidations Eliminations | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total Operating Revenues | (169,400) | (148,600) | (495,400) | (428,500)
Consolidations Eliminations | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Total Operating Revenues | (67,300) | (59,500) | (188,300) | (159,100)
Electric Distribution | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 2,630,900 | 2,410,300 | 6,822,500 | 7,039,800
Alternative Revenue Programs | (2,900) | (43,800) | 24,400 | (40,700)
Other Revenues | 4,800 | 4,800 | 13,900 | 15,200
Total Operating Revenues | 2,632,800 | 2,371,300 | 6,860,800 | 7,014,300
Electric Distribution | Operating Segments | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 2,434,700 | 2,234,500 | 6,284,600 | 6,495,300
Electric Distribution | Operating Segments | Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,465,500 | 1,375,900 | 3,747,100 | 3,982,100
Electric Distribution | Operating Segments | Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 857,800 | 764,100 | 2,248,500 | 2,244,700
Electric Distribution | Operating Segments | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 111,400 | 94,500 | 289,000 | 268,500
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 | 173,800 | 154,900 | 471,100 | 484,400
Electric Distribution | Operating Segments | Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 22,400 | 20,900 | 66,800 | 60,100
Natural Gas Distribution | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 220,200 | 219,800 | 1,486,500 | 1,647,700
Alternative Revenue Programs | (3,600) | (2,400) | 28,100 | 21,900
Other Revenues | 600 | 900 | 2,100 | 3,000
Total Operating Revenues | 217,200 | 218,300 | 1,516,700 | 1,672,600
Natural Gas Distribution | Operating Segments | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 189,300 | 146,900 | 1,359,800 | 1,483,300
Natural Gas Distribution | Operating Segments | Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 86,700 | 83,000 | 798,300 | 858,000
Natural Gas Distribution | Operating Segments | Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 71,000 | 33,700 | 434,500 | 483,600
Natural Gas Distribution | Operating Segments | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 31,600 | 30,200 | 127,000 | 141,700
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 | 29,000 | 71,600 | 122,200 | 160,500
Natural Gas Distribution | Operating Segments | Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,900 | 1,300 | 4,500 | 3,900
Electric Transmission | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 587,100 | 525,000 | 1,581,600 | 1,372,300
Alternative Revenue Programs | (45,200) | (33,600) | 1,900 | 57,600
Other Revenues | 100 | 200 | 400 | 500
Total Operating Revenues | 542,000 | 491,600 | 1,583,900 | 1,430,400
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 | 583,600 | 520,200 | 1,570,600 | 1,358,200
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 | 3,500 | 4,800 | 11,000 | 14,100
Water Distribution | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 66,100 | 68,600 | 174,000 | 178,200
Alternative Revenue Programs | 600 | (300) | (200) | (2,000)
Other Revenues | 400 | 300 | 900 | 800
Total Operating Revenues | 67,100 | 68,600 | 174,700 | 177,000
Water Distribution | Operating Segments | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 63,700 | 65,500 | 168,400 | 169,200
Water Distribution | Operating Segments | Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 43,700 | 44,700 | 111,800 | 112,600
Water Distribution | Operating Segments | Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 18,700 | 19,600 | 53,100 | 53,200
Water Distribution | Operating Segments | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,300 | 1,200 | 3,500 | 3,400
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 | 1,200 | 1,100 | 3,100 | 2,900
Water Distribution | Operating Segments | Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | $ 1,200 | $ 2,000 | $ 2,500 | $ 6,100

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