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v3.22.1

Business segment data (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2022 | Mar. 31, 2021
Segment Reporting Information [Line Items] |  |
Revenues | $ 1,416,559 | $ 1,227,938
Operating income | 67,343 | 85,164
Income from continuing operations | 31,733 | 52,116
Income from discontinued operations, net of tax | 30 | 15
Net income | 31,763 | 52,131
Electric |  |
Segment Reporting Information [Line Items] |  |
Revenues | 93,594 | 84,673
Operating income | 15,044 | 13,865
Natural gas distribution |  |
Segment Reporting Information [Line Items] |  |
Revenues | 450,418 | 350,206
Operating income | 56,256 | 53,573
Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | 11,120 | 9,913
Operating income | 11,882 | 12,536
Construction materials and contracting |  |
Segment Reporting Information [Line Items] |  |
Revenues | 309,836 | 265,659
Operating income | (44,605) | (34,889)
Construction services |  |
Segment Reporting Information [Line Items] |  |
Revenues | 551,591 | 517,470
Operating income | 29,498 | 40,277
Other |  |
Segment Reporting Information [Line Items] |  |
Revenues | 0 | 17
Operating income | (732) | (198)
Intersegment eliminations |  |
Segment Reporting Information [Line Items] |  |
Revenues | (31,730) | (30,935)
Intersegment eliminations | Electric |  |
Segment Reporting Information [Line Items] |  |
Revenues | (124) | (136)
Intersegment eliminations | Natural gas distribution |  |
Segment Reporting Information [Line Items] |  |
Revenues | (136) | (142)
Intersegment eliminations | Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | (25,940) | (26,229)
Intersegment eliminations | Construction materials and contracting |  |
Segment Reporting Information [Line Items] |  |
Revenues | (130) | (62)
Intersegment eliminations | Construction services |  |
Segment Reporting Information [Line Items] |  |
Revenues | (1,059) | (1,042)
Intersegment eliminations | Other |  |
Segment Reporting Information [Line Items] |  |
Revenues | (4,341) | (3,324)
Total intersegment operating revenues |  |
Segment Reporting Information [Line Items] |  |
Revenues | 0 | 0
Regulated operation |  |
Segment Reporting Information [Line Items] |  |
Revenues | 553,456 | 442,381
Income from continuing operations | 55,549 | 56,121
Regulated operation | Electric |  |
Segment Reporting Information [Line Items] |  |
Revenues | 93,594 | 84,673
Income from continuing operations | 11,278 | 10,749
Regulated operation | Natural gas distribution |  |
Segment Reporting Information [Line Items] |  |
Revenues | 450,418 | 350,206
Income from continuing operations | 36,315 | 36,178
Regulated operation | Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | 9,444 | 7,502
Income from continuing operations | 7,956 | 9,194
Regulated operation | Intersegment eliminations |  |
Segment Reporting Information [Line Items] |  |
Revenues | 26,193 | 26,268
Regulated operation | Intersegment eliminations | Electric |  |
Segment Reporting Information [Line Items] |  |
Revenues | 124 | 136
Regulated operation | Intersegment eliminations | Natural gas distribution |  |
Segment Reporting Information [Line Items] |  |
Revenues | 136 | 142
Regulated operation | Intersegment eliminations | Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | 25,933 | 25,990
Nonregulated operation |  |
Segment Reporting Information [Line Items] |  |
Revenues | 863,103 | 785,557
Income from continuing operations | (23,816) | (4,005)
Nonregulated operation | Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | 1,676 | 2,411
Income from continuing operations | (619) | (296)
Nonregulated operation | Construction materials and contracting |  |
Segment Reporting Information [Line Items] |  |
Revenues | 309,836 | 265,659
Income from continuing operations | (40,010) | (30,813)
Nonregulated operation | Construction services |  |
Segment Reporting Information [Line Items] |  |
Revenues | 551,591 | 517,470
Income from continuing operations | 21,324 | 29,825
Nonregulated operation | Other |  |
Segment Reporting Information [Line Items] |  |
Revenues | 0 | 17
Income from continuing operations | (4,511) | (2,721)
Nonregulated operation | Intersegment eliminations |  |
Segment Reporting Information [Line Items] |  |
Revenues | 5,537 | 4,667
Nonregulated operation | Intersegment eliminations | Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | 7 | 239
Nonregulated operation | Intersegment eliminations | Construction materials and contracting |  |
Segment Reporting Information [Line Items] |  |
Revenues | 130 | 62
Nonregulated operation | Intersegment eliminations | Construction services |  |
Segment Reporting Information [Line Items] |  |
Revenues | 1,059 | 1,042
Nonregulated operation | Intersegment eliminations | Other |  |
Segment Reporting Information [Line Items] |  |
Revenues | $ 4,341 | $ 3,324

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