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v3.23.3

Business segment data (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Sep. 30, 2022 | Jun. 30, 2022 | Mar. 31, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | $ 1,000,795 |  |  | $ 1,002,487 |  |  | $ 3,522,020 | $ 3,119,351
Operating income | 84,604 |  |  | 61,002 |  |  | 285,157 | 231,003
Income from continuing operations | 78,218 |  |  | 42,369 |  |  | 309,726 | 146,897
Discontinued operations, net of tax | (3,289) |  |  | 105,602 |  |  | (65,752) | 103,504
Net income | 74,929 | $ 130,692 | $ 38,353 | 147,971 | $ 70,667 | $ 31,763 | 243,974 | 250,401
Electric |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 108,089 |  |  | 99,283 |  |  | 294,775 | 278,518
Operating income | 28,718 |  |  | 30,395 |  |  | 71,372 | 53,764
Natural gas distribution |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 134,896 |  |  | 132,145 |  |  | 919,487 | 793,142
Operating income | (15,258) |  |  | (16,688) |  |  | 45,674 | 38,929
Pipeline |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 40,404 |  |  | 36,058 |  |  | 89,086 | 76,997
Operating income | 17,767 |  |  | 14,963 |  |  | 44,693 | 39,448
Construction services |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 717,406 |  |  | 735,001 |  |  | 2,218,672 | 1,970,694
Operating income | 50,091 |  |  | 34,949 |  |  | 139,619 | 110,588
Other |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 0 |  |  | 0 |  |  | 0 | 0
Operating income | 3,286 |  |  | (2,617) |  |  | (16,201) | (11,726)
Intersegment eliminations | Electric |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | (27) |  |  | (34) |  |  | (82) | (102)
Intersegment eliminations | Natural gas distribution |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | (69) |  |  | (69) |  |  | (208) | (206)
Intersegment eliminations | Pipeline |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | (3,701) |  |  | (3,581) |  |  | (37,889) | (37,309)
Intersegment eliminations | Construction services |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 0 |  |  | (2,037) |  |  | 0 | (4,391)
Intersegment eliminations | Other |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | (1,689) |  |  | (1,472) |  |  | (6,412) | (4,368)
Intersegment eliminations | Consolidated Operations |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | (5,486) |  |  | (7,193) |  |  | (44,591) | (46,376)
Total intersegment operating revenues | Consolidated Operations |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 5,486 |  |  | 7,193 |  |  | 44,591 | 46,376
Regulated operation |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 279,534 |  |  | 263,774 |  |  | 1,293,959 | 1,141,007
Income from continuing operations | 14,628 |  |  | 12,919 |  |  | 100,923 | 73,249
Regulated operation | Electric |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 108,089 |  |  | 99,283 |  |  | 294,775 | 278,518
Income from continuing operations | 20,942 |  |  | 21,596 |  |  | 53,887 | 37,476
Regulated operation | Natural gas distribution |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 134,896 |  |  | 132,145 |  |  | 919,487 | 793,142
Income from continuing operations | (17,764) |  |  | (18,058) |  |  | 18,007 | 10,758
Regulated operation | Pipeline |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 36,549 |  |  | 32,346 |  |  | 79,697 | 69,347
Income from continuing operations | 11,450 |  |  | 9,381 |  |  | 29,029 | 25,015
Regulated operation | Intersegment eliminations | Electric |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 27 |  |  | 34 |  |  | 82 | 102
Regulated operation | Intersegment eliminations | Natural gas distribution |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 69 |  |  | 69 |  |  | 208 | 206
Regulated operation | Intersegment eliminations | Pipeline |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 3,666 |  |  | 3,508 |  |  | 37,624 | 36,845
Regulated operation | Intersegment eliminations | Regulated Operations |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 3,762 |  |  | 3,611 |  |  | 37,914 | 37,153
Nonregulated operation |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 721,261 |  |  | 738,713 |  |  | 2,228,061 | 1,978,344
Income from continuing operations | 63,590 |  |  | 29,450 |  |  | 208,803 | 73,648
Nonregulated operation | Pipeline |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 3,855 |  |  | 3,712 |  |  | 9,389 | 7,650
Income from continuing operations | 508 |  |  | 779 |  |  | 337 | (179)
Nonregulated operation | Construction services |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 717,406 |  |  | 735,001 |  |  | 2,218,672 | 1,970,694
Income from continuing operations | 35,975 |  |  | 29,248 |  |  | 105,951 | 86,596
Nonregulated operation | Other |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 0 |  |  | 0 |  |  | 0 | 0
Income from continuing operations | 27,107 |  |  | (577) |  |  | 102,515 | (12,769)
Nonregulated operation | Intersegment eliminations | Pipeline |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 35 |  |  | 73 |  |  | 265 | 464
Nonregulated operation | Intersegment eliminations | Construction services |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 0 |  |  | 2,037 |  |  | 0 | 4,391
Nonregulated operation | Intersegment eliminations | Other |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | 1,689 |  |  | 1,472 |  |  | 6,412 | 4,368
Nonregulated operation | Intersegment eliminations | Non-regulated Operations |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Revenues | $ 1,724 |  |  | $ 3,582 |  |  | $ 6,677 | $ 9,223

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