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v3.21.1

Business segment data (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020
Segment Reporting Information [Line Items] |  |
Revenues | $ 1,227,938 | $ 1,197,373
Operating income (loss) | 85,164 | 57,070
Income from continuing operations | 52,116 | 25,539
Income (loss) from discontinued operations, net of tax | 15 | (409)
Net income | 52,131 | 25,130
Electric |  |
Segment Reporting Information [Line Items] |  |
Revenues | 84,673 | 85,908
Operating income (loss) | 13,865 | 14,859
Natural gas distribution |  |
Segment Reporting Information [Line Items] |  |
Revenues | 350,206 | 326,443
Operating income (loss) | 53,573 | 49,998
Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | 9,913 | 10,655
Operating income (loss) | 12,536 | 11,419
Construction materials and contracting |  |
Segment Reporting Information [Line Items] |  |
Revenues | 265,659 | 262,144
Operating income (loss) | (34,889) | (43,269)
Construction services |  |
Segment Reporting Information [Line Items] |  |
Revenues | 517,470 | 512,205
Operating income (loss) | 40,277 | 23,796
Other |  |
Segment Reporting Information [Line Items] |  |
Revenues | 17 | 18
Operating income (loss) | (198) | 267
Intersegment eliminations |  |
Segment Reporting Information [Line Items] |  |
Revenues | (30,935) | (31,085)
Intersegment eliminations | Electric |  |
Segment Reporting Information [Line Items] |  |
Revenues | (136) | (195)
Intersegment eliminations | Natural gas distribution |  |
Segment Reporting Information [Line Items] |  |
Revenues | (142) | (185)
Intersegment eliminations | Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | (26,229) | (25,199)
Intersegment eliminations | Construction materials and contracting |  |
Segment Reporting Information [Line Items] |  |
Revenues | (62) | (63)
Intersegment eliminations | Construction services |  |
Segment Reporting Information [Line Items] |  |
Revenues | (1,042) | (2,470)
Intersegment eliminations | Other |  |
Segment Reporting Information [Line Items] |  |
Revenues | (3,324) | (2,973)
Total intersegment operating revenues |  |
Segment Reporting Information [Line Items] |  |
Revenues | 0 | 0
Regulated operation |  |
Segment Reporting Information [Line Items] |  |
Revenues | 442,381 | 418,682
Income from continuing operations | 56,121 | 51,129
Regulated operation | Electric |  |
Segment Reporting Information [Line Items] |  |
Revenues | 84,673 | 85,908
Income from continuing operations | 10,749 | 11,374
Regulated operation | Natural gas distribution |  |
Segment Reporting Information [Line Items] |  |
Revenues | 350,206 | 326,443
Income from continuing operations | 36,178 | 32,369
Regulated operation | Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | 7,502 | 6,331
Income from continuing operations | 9,194 | 7,386
Regulated operation | Intersegment eliminations |  |
Segment Reporting Information [Line Items] |  |
Revenues | 26,268 | 25,563
Regulated operation | Intersegment eliminations | Electric |  |
Segment Reporting Information [Line Items] |  |
Revenues | 136 | 195
Regulated operation | Intersegment eliminations | Natural gas distribution |  |
Segment Reporting Information [Line Items] |  |
Revenues | 142 | 185
Regulated operation | Intersegment eliminations | Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | 25,990 | 25,183
Nonregulated operation |  |
Segment Reporting Information [Line Items] |  |
Revenues | 785,557 | 778,691
Income from continuing operations | (4,005) | (25,590)
Nonregulated operation | Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | 2,411 | 4,324
Income from continuing operations | (296) | (13)
Nonregulated operation | Construction materials and contracting |  |
Segment Reporting Information [Line Items] |  |
Revenues | 265,659 | 262,144
Income from continuing operations | (30,813) | (38,215)
Nonregulated operation | Construction services |  |
Segment Reporting Information [Line Items] |  |
Revenues | 517,470 | 512,205
Income from continuing operations | 29,825 | 16,823
Nonregulated operation | Other |  |
Segment Reporting Information [Line Items] |  |
Revenues | 17 | 18
Income from continuing operations | (2,721) | (4,185)
Nonregulated operation | Intersegment eliminations |  |
Segment Reporting Information [Line Items] |  |
Revenues | 4,667 | 5,522
Nonregulated operation | Intersegment eliminations | Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | 239 | 16
Nonregulated operation | Intersegment eliminations | Construction materials and contracting |  |
Segment Reporting Information [Line Items] |  |
Revenues | 62 | 63
Nonregulated operation | Intersegment eliminations | Construction services |  |
Segment Reporting Information [Line Items] |  |
Revenues | 1,042 | 2,470
Nonregulated operation | Intersegment eliminations | Other |  |
Segment Reporting Information [Line Items] |  |
Revenues | $ 3,324 | $ 2,973

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