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v3.23.1

Disaggregation of revenue (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2023 | Mar. 31, 2022
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | $ 1,737,337 | $ 1,416,559
Intersegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | (31,767) | (31,730)
Intrasegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | (39,585) | (46,033)
Natural gas transportation |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 48,487 | 43,955
Natural gas storage |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 3,861 | 3,719
Contracting services |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 114,983 | 114,267
Construction materials |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 232,502 | 241,732
Electrical & mechanical specialty contracting |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 590,263 | 392,808
Transmission & distribution specialty contracting |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 152,022 | 148,466
Other |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 23,230 | 21,460
Revenues from contracts with customers |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 1,730,121 | 1,409,053
Revenues out of scope |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 7,216 | 7,506
Residential utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 365,476 | 296,120
Commercial utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 241,274 | 199,209
Industrial utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 27,601 | 23,330
Other utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 1,774 | 1,750
Electric |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 95,602 | 93,594
Electric | Intersegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | (122) | (124)
Electric | Other |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 11,878 | 12,753
Electric | Revenues from contracts with customers |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 98,465 | 97,589
Electric | Revenues out of scope |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | (2,863) | (3,995)
Electric | Residential utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 37,825 | 37,304
Electric | Commercial utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 36,347 | 35,600
Electric | Industrial utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 10,763 | 10,306
Electric | Other utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 1,774 | 1,750
Natural gas distribution |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 565,517 | 450,418
Natural gas distribution | Intersegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | (150) | (136)
Natural gas distribution | Natural gas transportation |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 13,504 | 12,381
Natural gas distribution | Other |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 4,721 | 2,609
Natural gas distribution | Revenues from contracts with customers |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 567,491 | 450,303
Natural gas distribution | Revenues out of scope |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | (1,974) | 115
Natural gas distribution | Residential utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 327,651 | 258,816
Natural gas distribution | Commercial utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 204,927 | 163,609
Natural gas distribution | Industrial utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 16,838 | 13,024
Natural gas distribution | Other utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 0 | 0
Pipeline |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 14,331 | 11,120
Pipeline | Intersegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | (26,410) | (25,940)
Pipeline | Natural gas transportation |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 34,983 | 31,574
Pipeline | Natural gas storage |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 3,861 | 3,719
Pipeline | Other |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 1,859 | 1,709
Pipeline | Revenues from contracts with customers |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 14,293 | 11,062
Pipeline | Revenues out of scope |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 38 | 58
Construction materials and contracting |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 307,768 | 309,836
Construction materials and contracting | Intersegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | (132) | (130)
Construction materials and contracting | Intrasegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | (39,585) | (46,033)
Construction materials and contracting | Contracting services |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 114,983 | 114,267
Construction materials and contracting | Construction materials |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 232,502 | 241,732
Construction materials and contracting | Other |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 0 | 0
Construction materials and contracting | Revenues from contracts with customers |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 307,768 | 309,836
Construction materials and contracting | Revenues out of scope |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 0 | 0
Construction services |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 754,119 | 551,591
Construction services | Intersegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | (214) | (1,059)
Construction services | Electrical & mechanical specialty contracting |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 590,263 | 392,808
Construction services | Transmission & distribution specialty contracting |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 152,022 | 148,466
Construction services | Other |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 33 | 48
Construction services | Revenues from contracts with customers |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 742,104 | 540,263
Construction services | Revenues out of scope |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 12,015 | 11,328
Other |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 0 | 0
Other | Intersegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | (4,739) | (4,341)
Other | Other |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 4,739 | 4,341
Other | Revenues from contracts with customers |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | 0 | 0
Other | Revenues out of scope |  |
Disaggregation of Revenue [Line Items] |  |
Operating revenues: | $ 0 | $ 0

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