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v3.23.2

Disaggregation of revenue (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | $ 1,091,126 | $ 1,009,749 | $ 2,521,224 | $ 2,116,864
Intersegment eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | (11,165) | (10,875) | (39,105) | (39,183)
Natural gas transportation |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 46,065 | 43,423 | 94,553 | 87,378
Natural gas storage |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 3,758 | 2,896 | 7,620 | 6,615
Electrical & mechanical specialty contracting |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 568,307 | 507,233 | 1,158,570 | 900,041
Transmission & distribution specialty contracting |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 167,485 | 166,174 | 319,507 | 314,640
Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 22,068 | 18,208 | 42,132 | 36,768
Revenues from contracts with customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 1,079,031 | 1,001,352 | 2,501,913 | 2,100,961
Revenues out of scope |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 12,095 | 8,397 | 19,311 | 15,903
Residential utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 151,792 | 146,112 | 517,267 | 442,232
Commercial utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 109,458 | 106,369 | 350,731 | 305,578
Industrial utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 19,553 | 19,932 | 47,154 | 43,262
Other utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 1,710 | 1,880 | 3,484 | 3,630
Electric |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 90,989 | 85,551 | 186,686 | 179,235
Electric | Intersegment eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | (27) | (34) | (55) | (68)
Electric | Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 11,531 | 10,216 | 23,410 | 22,969
Electric | Revenues from contracts with customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 92,671 | 86,363 | 191,231 | 184,042
Electric | Revenues out of scope |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | (1,682) | (812) | (4,545) | (4,807)
Electric | Residential utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 30,825 | 29,363 | 68,650 | 66,667
Electric | Commercial utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 38,262 | 34,015 | 74,609 | 69,615
Electric | Industrial utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 10,370 | 10,923 | 21,133 | 21,229
Electric | Other utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 1,710 | 1,880 | 3,484 | 3,630
Natural gas distribution |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 218,995 | 210,510 | 784,590 | 660,998
Natural gas distribution | Intersegment eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | (69) | (71) | (139) | (137)
Natural gas distribution | Natural gas transportation |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 11,671 | 11,456 | 25,175 | 23,837
Natural gas distribution | Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 3,272 | 3,751 | 7,993 | 6,360
Natural gas distribution | Revenues from contracts with customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 216,220 | 213,248 | 783,789 | 663,621
Natural gas distribution | Revenues out of scope |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 2,775 | (2,738) | 801 | (2,623)
Natural gas distribution | Residential utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 120,967 | 116,749 | 448,617 | 375,565
Natural gas distribution | Commercial utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 71,196 | 72,354 | 276,122 | 235,963
Natural gas distribution | Industrial utility sales |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 9,183 | 9,009 | 26,021 | 22,033
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: | 34,209 | 29,818 | 48,683 | 40,938
Pipeline | Intersegment eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | (7,918) | (7,787) | (34,188) | (33,729)
Pipeline | Natural gas transportation |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 34,394 | 31,967 | 69,378 | 63,541
Pipeline | Natural gas storage |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 3,758 | 2,896 | 7,620 | 6,615
Pipeline | Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 3,937 | 2,676 | 5,797 | 4,387
Pipeline | Revenues from contracts with customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 34,171 | 29,752 | 48,607 | 40,814
Pipeline | Revenues out of scope |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 38 | 66 | 76 | 124
Construction services |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 746,933 | 683,870 | 1,501,265 | 1,235,693
Construction services | Intersegment eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 0 | (1,527) | 0 | (2,353)
Construction services | Electrical & mechanical specialty contracting |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 568,307 | 507,233 | 1,158,570 | 900,041
Construction services | Transmission & distribution specialty contracting |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 167,485 | 166,174 | 319,507 | 314,640
Construction services | Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 177 | 109 | 209 | 156
Construction services | Revenues from contracts with customers |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 735,969 | 671,989 | 1,478,286 | 1,212,484
Construction services | Revenues out of scope |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 10,964 | 11,881 | 22,979 | 23,209
Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 0 | 0 | 0 | 0
Other | Intersegment eliminations |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | (3,151) | (1,456) | (4,723) | (2,896)
Other | Other |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Operating revenues: | 3,151 | 1,456 | 4,723 | 2,896
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

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