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REVENUES (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | $ 4,106,500 | $ 3,276,800
Alternative Revenue Programs | 4,500 | 49,100
Other Revenues | 7,400 | 6,700
Total Operating Revenues | 4,118,355 | 3,332,575
CL&P |  |
Disaggregation of Revenue [Line Items] |  |
Total Operating Revenues | 1,541,189 | 1,121,291
NSTAR Electric |  |
Disaggregation of Revenue [Line Items] |  |
Total Operating Revenues | 1,014,227 | 947,615
PSNH |  |
Disaggregation of Revenue [Line Items] |  |
Total Operating Revenues | 347,981 | 326,116
Total Retail Tariff Sales Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 3,511,000 | 2,904,500
Residential |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 2,217,200 | 1,792,000
Commercial |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 1,126,800 | 969,100
Industrial |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 167,000 | 143,400
Wholesale Transmission Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 154,700 | 112,500
Wholesale Market Sales Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 411,200 | 224,400
Other Revenues from Contracts with Customers |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 29,600 | 35,400
Operating Segments | CL&P |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 1,733,500 | 1,250,800
Alternative Revenue Programs | (18,900) | 27,400
Other Revenues | 2,700 | 2,900
Operating Segments | NSTAR Electric |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 1,200,600 | 1,097,100
Alternative Revenue Programs | (9,100) | 7,800
Other Revenues | 2,400 | 2,000
Operating Segments | PSNH |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 434,100 | 373,900
Alternative Revenue Programs | (19,700) | 7,600
Other Revenues | 900 | 800
Operating Segments | Total Retail Tariff Sales Revenues | CL&P |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 1,193,700 | 912,500
Operating Segments | Total Retail Tariff Sales Revenues | NSTAR Electric |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 912,700 | 865,600
Operating Segments | Total Retail Tariff Sales Revenues | PSNH |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 295,100 | 271,600
Operating Segments | Residential | CL&P |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 801,200 | 626,800
Operating Segments | Residential | NSTAR Electric |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 506,200 | 462,200
Operating Segments | Residential | PSNH |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 181,900 | 165,100
Operating Segments | Commercial | CL&P |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 344,100 | 252,400
Operating Segments | Commercial | NSTAR Electric |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 375,700 | 373,500
Operating Segments | Commercial | PSNH |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 88,300 | 82,000
Operating Segments | Industrial | CL&P |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 48,400 | 33,300
Operating Segments | Industrial | NSTAR Electric |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 30,800 | 29,900
Operating Segments | Industrial | PSNH |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 24,900 | 24,500
Operating Segments | Wholesale Transmission Revenues | CL&P |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 251,100 | 200,700
Operating Segments | Wholesale Transmission Revenues | NSTAR Electric |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 218,700 | 188,800
Operating Segments | Wholesale Transmission Revenues | PSNH |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 124,200 | 84,600
Operating Segments | Wholesale Market Sales Revenues | CL&P |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 280,000 | 121,200
Operating Segments | Wholesale Market Sales Revenues | NSTAR Electric |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 57,300 | 31,600
Operating Segments | Wholesale Market Sales Revenues | PSNH |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 10,500 | 12,500
Operating Segments | Other Revenues from Contracts with Customers | CL&P |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 8,700 | 16,400
Operating Segments | Other Revenues from Contracts with Customers | NSTAR Electric |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 11,900 | 11,100
Operating Segments | Other Revenues from Contracts with Customers | PSNH |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 4,300 | 5,200
Other |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 439,000 | 443,600
Alternative Revenue Programs | 0 | 0
Other Revenues | 0 | 0
Total Operating Revenues | 439,000 | 443,600
Other | Total Retail Tariff Sales Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 0 | 0
Other | Residential |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 0 | 0
Other | Commercial |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 0 | 0
Other | Industrial |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 0 | 0
Other | Wholesale Transmission Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 0 | 0
Other | Wholesale Market Sales Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 0 | 0
Other | Other Revenues from Contracts with Customers |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 439,000 | 443,600
Eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | (883,000) | (809,800)
Alternative Revenue Programs | 45,200 | (26,800)
Other Revenues | 0 | 0
Total Operating Revenues | (837,800) | (836,600)
Eliminations | Total Retail Tariff Sales Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | (7,900) | (6,800)
Eliminations | Residential |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 0 | 0
Eliminations | Commercial |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | (2,000) | (1,700)
Eliminations | Industrial |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | (5,900) | (5,100)
Eliminations | Wholesale Transmission Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | (439,300) | (361,600)
Eliminations | Wholesale Market Sales Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 0 | 0
Eliminations | Other Revenues from Contracts with Customers |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | (435,800) | (441,400)
Consolidations Eliminations | CL&P |  |
Disaggregation of Revenue [Line Items] |  |
Total Operating Revenues | (176,100) | (159,800)
Consolidations Eliminations | NSTAR Electric |  |
Disaggregation of Revenue [Line Items] |  |
Total Operating Revenues | (179,700) | (159,300)
Consolidations Eliminations | PSNH |  |
Disaggregation of Revenue [Line Items] |  |
Total Operating Revenues | (67,300) | (56,200)
Electric Distribution | Operating Segments |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 2,769,600 | 2,243,000
Alternative Revenue Programs | 2,200 | 13,200
Other Revenues | 5,900 | 5,500
Total Operating Revenues | 2,777,700 | 2,261,700
Electric Distribution | Operating Segments | Total Retail Tariff Sales Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 2,401,000 | 2,049,300
Electric Distribution | Operating Segments | Residential |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 1,489,300 | 1,254,100
Electric Distribution | Operating Segments | Commercial |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 807,600 | 707,500
Electric Distribution | Operating Segments | Industrial |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 104,100 | 87,700
Electric Distribution | Operating Segments | Wholesale Transmission Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 0 | 0
Electric Distribution | Operating Segments | Wholesale Market Sales Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 347,800 | 165,300
Electric Distribution | Operating Segments | Other Revenues from Contracts with Customers |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 20,800 | 28,400
Natural Gas Distribution | Operating Segments |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 1,133,900 | 873,800
Alternative Revenue Programs | 6,400 | 31,500
Other Revenues | 1,100 | 700
Total Operating Revenues | 1,141,400 | 906,000
Natural Gas Distribution | Operating Segments | Total Retail Tariff Sales Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 1,070,200 | 814,500
Natural Gas Distribution | Operating Segments | Residential |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 696,500 | 507,600
Natural Gas Distribution | Operating Segments | Commercial |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 305,900 | 247,100
Natural Gas Distribution | Operating Segments | Industrial |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 67,800 | 59,800
Natural Gas Distribution | Operating Segments | Wholesale Transmission Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 0 | 0
Natural Gas Distribution | Operating Segments | Wholesale Market Sales Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 62,300 | 58,200
Natural Gas Distribution | Operating Segments | Other Revenues from Contracts with Customers |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 1,400 | 1,100
Electric Transmission | Operating Segments |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 597,600 | 478,000
Alternative Revenue Programs | (49,900) | 29,600
Other Revenues | 100 | 200
Total Operating Revenues | 547,800 | 507,800
Electric Transmission | Operating Segments | Total Retail Tariff Sales Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 0 | 0
Electric Transmission | Operating Segments | Residential |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 0 | 0
Electric Transmission | Operating Segments | Commercial |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 0 | 0
Electric Transmission | Operating Segments | Industrial |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 0 | 0
Electric Transmission | Operating Segments | Wholesale Transmission Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 594,000 | 474,100
Electric Transmission | Operating Segments | Wholesale Market Sales Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 0 | 0
Electric Transmission | Operating Segments | Other Revenues from Contracts with Customers |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 3,600 | 3,900
Water Distribution | Operating Segments |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 49,400 | 48,200
Alternative Revenue Programs | 600 | 1,600
Other Revenues | 300 | 300
Total Operating Revenues | 50,300 | 50,100
Water Distribution | Operating Segments | Total Retail Tariff Sales Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 47,700 | 47,500
Water Distribution | Operating Segments | Residential |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 31,400 | 30,300
Water Distribution | Operating Segments | Commercial |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 15,300 | 16,200
Water Distribution | Operating Segments | Industrial |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 1,000 | 1,000
Water Distribution | Operating Segments | Wholesale Transmission Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 0 | 0
Water Distribution | Operating Segments | Wholesale Market Sales Revenues |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | 1,100 | 900
Water Distribution | Operating Segments | Other Revenues from Contracts with Customers |  |
Disaggregation of Revenue [Line Items] |  |
Revenues from Contracts with Customers | $ 600 | $ (200)

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