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v3.20.1

Disaggregation of revenue (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2020 | Mar. 31, 2019
Disaggregation of Revenue [Line Items] |  |
Revenues | $ 1,197,373 | $ 1,091,191
Intersegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | (31,085) | (32,003)
Intrasegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | (44,104) | (35,140)
Natural gas transportation |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 39,230 | 36,628
Natural gas gathering |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 2,090 | 2,121
Natural gas storage |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 3,046 | 2,646
Contracting services |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 98,401 | 83,039
Construction materials |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 207,910 | 179,309
Inside specialty contracting |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 372,209 | 299,530
Outside specialty contracting |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 130,150 | 107,398
Other |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 17,531 | 23,590
Revenues from contracts with customers |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 1,183,547 | 1,081,040
Revenues out of scope |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 13,826 | 10,151
Residential utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 219,050 | 237,164
Commercial utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 148,583 | 157,464
Industrial utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 18,888 | 17,495
Other utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 1,648 | 1,799
Electric |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 85,908 | 92,566
Electric | Intersegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | (195) | 0
Electric | Other |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 8,450 | 9,121
Electric | Revenues from contracts with customers |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 86,206 | 92,030
Electric | Revenues out of scope |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | (298) | 536
Electric | Residential utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 32,349 | 36,555
Electric | Commercial utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 33,587 | 35,671
Electric | Industrial utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 10,367 | 8,884
Electric | Other utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 1,648 | 1,799
Natural gas distribution |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 326,443 | 342,147
Natural gas distribution | Intersegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | (185) | 0
Natural gas distribution | Natural gas transportation |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 11,798 | 11,570
Natural gas distribution | Other |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 2,498 | 3,913
Natural gas distribution | Revenues from contracts with customers |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 324,329 | 346,496
Natural gas distribution | Revenues out of scope |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 2,114 | (4,349)
Natural gas distribution | Residential utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 186,701 | 200,609
Natural gas distribution | Commercial utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 114,996 | 121,793
Natural gas distribution | Industrial utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 8,521 | 8,611
Natural gas distribution | Other utility sales |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 0 | 0
Pipeline |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 10,655 | 8,613
Pipeline | Intersegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | (25,199) | (23,955)
Pipeline | Natural gas transportation |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 27,432 | 25,058
Pipeline | Natural gas gathering |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 2,090 | 2,121
Pipeline | Natural gas storage |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 3,046 | 2,646
Pipeline | Other |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 3,241 | 2,696
Pipeline | Revenues from contracts with customers |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 10,610 | 8,566
Pipeline | Revenues out of scope |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 45 | 47
Construction materials and contracting |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 262,144 | 227,113
Construction materials and contracting | Intersegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | (63) | (95)
Construction materials and contracting | Intrasegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | (44,104) | (35,140)
Construction materials and contracting | Contracting services |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 98,401 | 83,039
Construction materials and contracting | Construction materials |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 207,910 | 179,309
Construction materials and contracting | Other |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 0 | 0
Construction materials and contracting | Revenues from contracts with customers |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 262,144 | 227,113
Construction materials and contracting | Revenues out of scope |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 0 | 0
Construction services |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 512,205 | 420,733
Construction services | Intersegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | (2,470) | (129)
Construction services | Inside specialty contracting |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 372,209 | 299,530
Construction services | Outside specialty contracting |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 130,150 | 107,398
Construction services | Other |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 351 | 17
Construction services | Revenues from contracts with customers |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 500,240 | 406,816
Construction services | Revenues out of scope |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 11,965 | 13,917
Other |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 18 | 19
Other | Intersegment eliminations |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | (2,973) | (7,824)
Other | Other |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 2,991 | 7,843
Other | Revenues from contracts with customers |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | 18 | 19
Other | Revenues out of scope |  |
Disaggregation of Revenue [Line Items] |  |
Revenues | $ 0 | $ 0

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