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v3.23.1

REVENUES (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2021 | Sep. 01, 2021
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | $ 3,751,800 | $ 3,452,000 |  |
Alternative Revenue Programs | 36,900 | 15,800 |  |
Other Revenues | 6,900 | 3,500 |  |
Operating Revenues | 3,795,643 | 3,471,310 |  |
Customer Credits at CL&P related to PURA Settlement Agreement and Storm Performance Penalty | 0 | (58,412) |  |
CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating Revenues | 1,338,905 | 1,285,831 |  |
Customer Credits at CL&P related to PURA Settlement Agreement and Storm Performance Penalty | 0 | (58,412) |  |
CL&P | Unfavorable Regulatory Action |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Loss contingency, estimate of possible earnings impact, non-compliance with performance standards |  |  |  | $ 28,400
CL&P | Unfavorable Regulatory Action | Sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Customer Credits at CL&P related to PURA Settlement Agreement and Storm Performance Penalty |  |  | $ 65,000 |
NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating Revenues | 956,283 | 863,176 |  |
PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating Revenues | 420,155 | 339,427 |  |
Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 3,347,100 | 2,857,900 |  |
Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 2,069,500 | 1,771,200 |  |
Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,122,900 | 932,400 |  |
Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 154,700 | 154,300 |  |
Wholesale Transmission Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 109,700 | 105,900 |  |
Wholesale Market Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 267,200 | 399,800 |  |
Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 27,800 | 30,400 |  |
Amortization of/(Reserve for) Revenues Subject to Refund |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers |  | 58,000 |  |
Operating Segments | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,451,800 | 1,430,100 |  |
Alternative Revenue Programs | 24,600 | 1,300 |  |
Other Revenues | 2,200 | 100 |  |
Operating Segments | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,104,400 | 1,004,700 |  |
Alternative Revenue Programs | (9,500) | (8,200) |  |
Other Revenues | 2,500 | 2,000 |  |
Operating Segments | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 461,100 | 395,100 |  |
Alternative Revenue Programs | 9,600 | (3,300) |  |
Other Revenues | 1,000 | 900 |  |
Operating Segments | Total Retail Tariff Sales Revenues | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,091,400 | 874,800 |  |
Operating Segments | Total Retail Tariff Sales Revenues | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 884,700 | 770,000 |  |
Operating Segments | Total Retail Tariff Sales Revenues | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 365,200 | 292,900 |  |
Operating Segments | Residential | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 762,200 | 599,100 |  |
Operating Segments | Residential | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 467,800 | 404,600 |  |
Operating Segments | Residential | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 234,000 | 182,500 |  |
Operating Segments | Commercial | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 295,300 | 242,200 |  |
Operating Segments | Commercial | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 384,300 | 331,300 |  |
Operating Segments | Commercial | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 108,600 | 88,400 |  |
Operating Segments | Industrial | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 33,900 | 33,500 |  |
Operating Segments | Industrial | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 32,600 | 34,100 |  |
Operating Segments | Industrial | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 22,600 | 22,000 |  |
Operating Segments | Wholesale Transmission Revenues | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 195,800 | 209,100 |  |
Operating Segments | Wholesale Transmission Revenues | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 167,800 | 165,200 |  |
Operating Segments | Wholesale Transmission Revenues | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 71,400 | 71,900 |  |
Operating Segments | Wholesale Market Sales Revenues | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 154,600 | 279,900 |  |
Operating Segments | Wholesale Market Sales Revenues | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 41,100 | 57,900 |  |
Operating Segments | Wholesale Market Sales Revenues | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 21,600 | 27,700 |  |
Operating Segments | Other Revenues from Contracts with Customers | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 9,300 | 7,900 |  |
Operating Segments | Other Revenues from Contracts with Customers | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 10,800 | 11,600 |  |
Operating Segments | Other Revenues from Contracts with Customers | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 2,900 | 2,600 |  |
Operating Segments | Amortization of/(Reserve for) Revenues Subject to Refund | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 700 | 58,400 |  |
Operating Segments | Amortization of/(Reserve for) Revenues Subject to Refund | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 |  |
Operating Segments | Amortization of/(Reserve for) Revenues Subject to Refund | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 0 | 0 |  |
Operating Segments | Amortization Of (Reserves For) Revenues Subject To Refund | CL&P | Unfavorable Regulatory Action |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers |  |  | $ 93,400 |
Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 413,800 | 383,500 |  |
Alternative Revenue Programs | 0 | 0 |  |
Other Revenues | 0 | 0 |  |
Operating Revenues | 413,800 | 383,500 |  |
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 | 24,400 |  |
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 | 413,800 | 359,100 |  |
Other | Amortization of/(Reserve for) Revenues Subject to Refund |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers |  | 0 |  |
Eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (744,000) | (723,400) |  |
Alternative Revenue Programs | (16,900) | 13,600 |  |
Other Revenues | 0 | 0 |  |
Operating Revenues | (760,900) | (709,800) |  |
Eliminations | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (6,100) | (5,600) |  |
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 | (1,000) | (1,100) |  |
Eliminations | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (5,100) | (4,500) |  |
Eliminations | Wholesale Transmission Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | (325,300) | (364,700) |  |
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 | (412,600) | (353,100) |  |
Eliminations | Amortization of/(Reserve for) Revenues Subject to Refund |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers |  | 0 |  |
Consolidations Eliminations | CL&P |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating Revenues | (139,700) | (145,700) |  |
Consolidations Eliminations | NSTAR Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating Revenues | (141,100) | (135,300) |  |
Consolidations Eliminations | PSNH |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating Revenues | (51,500) | (53,300) |  |
Electric Distribution | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 2,577,100 | 2,378,700 |  |
Alternative Revenue Programs | 6,000 | 4,800 |  |
Other Revenues | 5,500 | 2,800 |  |
Operating Revenues | 2,588,600 | 2,386,300 |  |
Electric Distribution | Operating Segments | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 2,341,500 | 1,937,100 |  |
Electric Distribution | Operating Segments | Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,464,000 | 1,186,200 |  |
Electric Distribution | Operating Segments | Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 788,400 | 661,300 |  |
Electric Distribution | Operating Segments | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 89,100 | 89,600 |  |
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 | 217,300 | 365,500 |  |
Electric Distribution | Operating Segments | Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 18,300 | 17,700 |  |
Electric Distribution | Operating Segments | Amortization of/(Reserve for) Revenues Subject to Refund |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers |  | 58,400 |  |
Natural Gas Distribution | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,016,800 | 917,000 |  |
Alternative Revenue Programs | 27,400 | 10,200 |  |
Other Revenues | 1,000 | 400 |  |
Operating Revenues | 1,045,200 | 927,600 |  |
Natural Gas Distribution | Operating Segments | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 966,200 | 882,500 |  |
Natural Gas Distribution | Operating Segments | Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 576,600 | 556,800 |  |
Natural Gas Distribution | Operating Segments | Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 320,000 | 257,600 |  |
Natural Gas Distribution | Operating Segments | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 69,600 | 68,100 |  |
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 | 49,100 | 33,500 |  |
Natural Gas Distribution | Operating Segments | Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,500 | 1,000 |  |
Natural Gas Distribution | Operating Segments | Amortization of/(Reserve for) Revenues Subject to Refund |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers |  | 0 |  |
Electric Transmission | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 439,700 | 450,000 |  |
Alternative Revenue Programs | 18,700 | (15,000) |  |
Other Revenues | 200 | 200 |  |
Operating Revenues | 458,600 | 435,200 |  |
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 | 435,000 | 446,200 |  |
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 | 4,700 | 3,800 |  |
Electric Transmission | Operating Segments | Amortization of/(Reserve for) Revenues Subject to Refund |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers |  | 0 |  |
Water Distribution | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 48,400 | 46,200 |  |
Alternative Revenue Programs | 1,700 | 2,200 |  |
Other Revenues | 200 | 100 |  |
Operating Revenues | 50,300 | 48,500 |  |
Water Distribution | Operating Segments | Total Retail Tariff Sales Revenues |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 45,500 | 43,900 |  |
Water Distribution | Operating Segments | Residential |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 28,900 | 28,200 |  |
Water Distribution | Operating Segments | Commercial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 15,500 | 14,600 |  |
Water Distribution | Operating Segments | Industrial |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | 1,100 | 1,100 |  |
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 | 800 | 800 |  |
Water Distribution | Operating Segments | Other Revenues from Contracts with Customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers | $ 2,100 | 1,900 |  |
Water Distribution | Operating Segments | Amortization of/(Reserve for) Revenues Subject to Refund |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenues from Contracts with Customers |  | $ (400) |  |

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