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v3.23.1

Business segment data (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2023 | Mar. 31, 2022
Segment Reporting Information [Line Items] |  |
Revenues | $ 1,737,337 | $ 1,416,559
Operating income | 74,472 | 67,343
Income from continuing operations | 38,343 | 31,733
Discontinued operations, net of tax | 10 | 30
Net income | 38,353 | 31,763
Electric |  |
Segment Reporting Information [Line Items] |  |
Revenues | 95,602 | 93,594
Operating income | 21,091 | 15,044
Natural gas distribution |  |
Segment Reporting Information [Line Items] |  |
Revenues | 565,517 | 450,418
Operating income | 58,505 | 56,256
Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | 14,331 | 11,120
Operating income | 13,040 | 11,882
Construction materials and contracting |  |
Segment Reporting Information [Line Items] |  |
Revenues | 307,768 | 309,836
Operating income | (44,563) | (44,605)
Construction services |  |
Segment Reporting Information [Line Items] |  |
Revenues | 754,119 | 551,591
Operating income | 35,217 | 29,498
Other |  |
Segment Reporting Information [Line Items] |  |
Revenues | 0 | 0
Operating income | (8,818) | (732)
Intersegment eliminations |  |
Segment Reporting Information [Line Items] |  |
Revenues | (31,767) | (31,730)
Intersegment eliminations | Electric |  |
Segment Reporting Information [Line Items] |  |
Revenues | (122) | (124)
Intersegment eliminations | Natural gas distribution |  |
Segment Reporting Information [Line Items] |  |
Revenues | (150) | (136)
Intersegment eliminations | Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | (26,410) | (25,940)
Intersegment eliminations | Construction materials and contracting |  |
Segment Reporting Information [Line Items] |  |
Revenues | (132) | (130)
Intersegment eliminations | Construction services |  |
Segment Reporting Information [Line Items] |  |
Revenues | (214) | (1,059)
Intersegment eliminations | Other |  |
Segment Reporting Information [Line Items] |  |
Revenues | (4,739) | (4,341)
Total intersegment operating revenues |  |
Segment Reporting Information [Line Items] |  |
Revenues | 31,767 | 31,730
Regulated operation |  |
Segment Reporting Information [Line Items] |  |
Revenues | 673,757 | 553,456
Income from continuing operations | 64,294 | 55,549
Regulated operation | Electric |  |
Segment Reporting Information [Line Items] |  |
Revenues | 95,602 | 93,594
Income from continuing operations | 16,607 | 11,278
Regulated operation | Natural gas distribution |  |
Segment Reporting Information [Line Items] |  |
Revenues | 565,517 | 450,418
Income from continuing operations | 38,928 | 36,315
Regulated operation | Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | 12,638 | 9,444
Income from continuing operations | 8,759 | 7,956
Regulated operation | Intersegment eliminations |  |
Segment Reporting Information [Line Items] |  |
Revenues | 26,531 | 26,193
Regulated operation | Intersegment eliminations | Electric |  |
Segment Reporting Information [Line Items] |  |
Revenues | 122 | 124
Regulated operation | Intersegment eliminations | Natural gas distribution |  |
Segment Reporting Information [Line Items] |  |
Revenues | 150 | 136
Regulated operation | Intersegment eliminations | Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | 26,259 | 25,933
Nonregulated operation |  |
Segment Reporting Information [Line Items] |  |
Revenues | 1,063,580 | 863,103
Income from continuing operations | (25,951) | (23,816)
Nonregulated operation | Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | 1,693 | 1,676
Income from continuing operations | (460) | (619)
Nonregulated operation | Construction materials and contracting |  |
Segment Reporting Information [Line Items] |  |
Revenues | 307,768 | 309,836
Income from continuing operations | (41,320) | (40,010)
Nonregulated operation | Construction services |  |
Segment Reporting Information [Line Items] |  |
Revenues | 754,119 | 551,591
Income from continuing operations | 26,074 | 21,324
Nonregulated operation | Other |  |
Segment Reporting Information [Line Items] |  |
Revenues | 0 | 0
Income from continuing operations | (10,245) | (4,511)
Nonregulated operation | Intersegment eliminations |  |
Segment Reporting Information [Line Items] |  |
Revenues | 5,236 | 5,537
Nonregulated operation | Intersegment eliminations | Pipeline |  |
Segment Reporting Information [Line Items] |  |
Revenues | 151 | 7
Nonregulated operation | Intersegment eliminations | Construction materials and contracting |  |
Segment Reporting Information [Line Items] |  |
Revenues | 132 | 130
Nonregulated operation | Intersegment eliminations | Construction services |  |
Segment Reporting Information [Line Items] |  |
Revenues | 214 | 1,059
Nonregulated operation | Intersegment eliminations | Other |  |
Segment Reporting Information [Line Items] |  |
Revenues | $ 4,739 | $ 4,341

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