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v3.23.3

Disaggregation of revenue (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | $ 1,000,795 | $ 1,002,487 | $ 3,522,020 | $ 3,119,351
Natural gas transportation |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 48,388 | 44,054 | 142,941 | 131,432
Natural gas storage |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 4,808 | 3,595 | 12,427 | 10,210
Electrical & mechanical specialty contracting |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 514,378 | 543,717 | 1,672,948 | 1,443,758
Transmission & distribution specialty contracting |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 192,056 | 181,550 | 511,563 | 496,190
Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 24,098 | 19,739 | 66,231 | 56,507
Revenues from contracts with customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 991,276 | 989,085 | 3,493,191 | 3,090,046
Revenues out of scope |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 9,519 | 13,402 | 28,829 | 29,305
Residential utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 103,036 | 101,055 | 620,304 | 543,287
Commercial utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 90,114 | 82,519 | 440,846 | 388,097
Industrial utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 18,019 | 18,047 | 65,173 | 61,309
Other utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 1,865 | 2,002 | 5,349 | 5,632
Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 108,089 | 99,283 | 294,775 | 278,518
Electric | Intersegment eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | (27) | (34) | (82) | (102)
Electric | Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 14,701 | 10,758 | 38,111 | 33,727
Electric | Revenues from contracts with customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 111,343 | 99,330 | 302,574 | 283,372
Electric | Revenues out of scope |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | (3,254) | (47) | (7,799) | (4,854)
Electric | Residential utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 34,303 | 36,981 | 102,953 | 103,648
Electric | Commercial utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 49,754 | 38,785 | 124,363 | 108,400
Electric | Industrial utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 10,747 | 10,838 | 31,880 | 32,067
Electric | Other utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 1,865 | 2,002 | 5,349 | 5,632
Natural gas distribution |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 134,896 | 132,145 | 919,487 | 793,142
Natural gas distribution | Intersegment eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | (69) | (69) | (208) | (206)
Natural gas distribution | Natural gas transportation |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 13,050 | 11,910 | 38,225 | 35,747
Natural gas distribution | Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 3,881 | 3,495 | 11,874 | 9,854
Natural gas distribution | Revenues from contracts with customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 133,227 | 130,353 | 917,018 | 793,973
Natural gas distribution | Revenues out of scope |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 1,669 | 1,792 | 2,469 | (831)
Natural gas distribution | Residential utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 68,733 | 64,074 | 517,351 | 439,639
Natural gas distribution | Commercial utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 40,360 | 43,734 | 316,483 | 279,697
Natural gas distribution | Industrial utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 7,272 | 7,209 | 33,293 | 29,242
Natural gas distribution | Other utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 0 | 0 | 0 | 0
Pipeline |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 40,404 | 36,058 | 89,086 | 76,997
Pipeline | Intersegment eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | (3,701) | (3,581) | (37,889) | (37,309)
Pipeline | Natural gas transportation |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 35,338 | 32,144 | 104,716 | 95,685
Pipeline | Natural gas storage |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 4,808 | 3,595 | 12,427 | 10,210
Pipeline | Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 3,916 | 3,814 | 9,713 | 8,201
Pipeline | Revenues from contracts with customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 40,361 | 35,972 | 88,967 | 76,787
Pipeline | Revenues out of scope |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 43 | 86 | 119 | 210
Construction services |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 717,406 | 735,001 | 2,218,672 | 1,970,694
Construction services | Intersegment eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 0 | (2,037) | 0 | (4,391)
Construction services | Electrical & mechanical specialty contracting |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 514,378 | 543,717 | 1,672,948 | 1,443,758
Construction services | Transmission & distribution specialty contracting |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 192,056 | 181,550 | 511,563 | 496,190
Construction services | Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | (89) | 200 | 121 | 357
Construction services | Revenues from contracts with customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 706,345 | 723,430 | 2,184,632 | 1,935,914
Construction services | Revenues out of scope |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 11,061 | 11,571 | 34,040 | 34,780
Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 0 | 0 | 0 | 0
Other | Intersegment eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | (1,689) | (1,472) | (6,412) | (4,368)
Other | Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 1,689 | 1,472 | 6,412 | 4,368
Other | Revenues from contracts with customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 0 | 0 | 0 | 0
Other | Revenues out of scope |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 0 | 0 | 0 | 0
Consolidated Operations | Intersegment eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | $ (5,486) | $ (7,193) | $ (44,591) | $ (46,376)

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