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v3.21.2

Business segment data (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 | Mar. 31, 2021 | Jun. 30, 2020 | Mar. 31, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | $ 1,423,657 |  | $ 1,362,928 |  | $ 2,651,595 | $ 2,560,302
Operating income | 137,689 |  | 138,254 |  | 222,853 | 195,325
Income from continuing operations | 100,171 |  | 99,842 |  | 152,287 | 125,381
Income (loss) from discontinued operations, net of tax | 19 |  | (139) |  | 34 | (548)
Net income | 100,190 | $ 52,131 | 99,703 | $ 25,130 | 152,321 | 124,833
Electric |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 83,650 |  | 76,438 |  | 168,324 | 162,346
Operating income | 12,806 |  | 12,810 |  | 26,672 | 27,669
Natural gas distribution |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 153,788 |  | 141,494 |  | 503,994 | 467,937
Operating income | 3,601 |  | 678 |  | 57,173 | 50,677
Pipeline |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 27,773 |  | 27,658 |  | 37,685 | 38,313
Operating income | 11,076 |  | 12,225 |  | 23,612 | 23,644
Construction materials and contracting |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 633,674 |  | 621,045 |  | 899,333 | 883,190
Operating income | 72,452 |  | 74,741 |  | 37,563 | 31,472
Construction services |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 524,744 |  | 496,405 |  | 1,042,214 | 1,008,610
Operating income | 37,774 |  | 37,882 |  | 78,051 | 61,678
Other |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 28 |  | (112) |  | 45 | (94)
Operating income | (20) |  | (82) |  | (218) | 185
Intersegment eliminations |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | (12,440) |  | (12,222) |  | (43,375) | (43,306)
Intersegment eliminations | Electric |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | (136) |  | (196) |  | (271) | (391)
Intersegment eliminations | Natural gas distribution |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | (142) |  | (185) |  | (284) | (370)
Intersegment eliminations | Pipeline |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | (7,862) |  | (7,999) |  | (34,092) | (33,198)
Intersegment eliminations | Construction materials and contracting |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | (142) |  | (90) |  | (204) | (152)
Intersegment eliminations | Construction services |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | (797) |  | (779) |  | (1,839) | (3,249)
Intersegment eliminations | Other |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | (3,361) |  | (2,973) |  | (6,685) | (5,946)
Total intersegment operating revenues |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 0 |  | 0 |  | 0 | 0
Regulated operation |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 260,568 |  | 241,353 |  | 702,951 | 660,035
Income from continuing operations | 17,686 |  | 19,878 |  | 73,808 | 71,007
Regulated operation | Electric |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 83,650 |  | 76,438 |  | 168,324 | 162,346
Income from continuing operations | 10,304 |  | 12,153 |  | 21,054 | 23,527
Regulated operation | Natural gas distribution |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 153,788 |  | 141,494 |  | 503,994 | 467,937
Income from continuing operations | (707) |  | (959) |  | 35,471 | 31,410
Regulated operation | Pipeline |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 23,130 |  | 23,421 |  | 30,633 | 29,752
Income from continuing operations | 8,089 |  | 8,684 |  | 17,283 | 16,070
Regulated operation | Intersegment eliminations |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 7,973 |  | 8,238 |  | 34,240 | 33,801
Regulated operation | Intersegment eliminations | Electric |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 136 |  | 196 |  | 271 | 391
Regulated operation | Intersegment eliminations | Natural gas distribution |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 142 |  | 185 |  | 284 | 370
Regulated operation | Intersegment eliminations | Pipeline |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 7,695 |  | 7,857 |  | 33,685 | 33,040
Nonregulated operation |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 1,163,089 |  | 1,121,575 |  | 1,948,644 | 1,900,267
Income from continuing operations | 82,485 |  | 79,964 |  | 78,479 | 54,374
Nonregulated operation | Pipeline |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 4,643 |  | 4,237 |  | 7,052 | 8,561
Income from continuing operations | 1,106 |  | 268 |  | 810 | 255
Nonregulated operation | Construction materials and contracting |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 633,674 |  | 621,045 |  | 899,333 | 883,190
Income from continuing operations | 51,396 |  | 53,020 |  | 20,584 | 14,806
Nonregulated operation | Construction services |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 524,744 |  | 496,405 |  | 1,042,214 | 1,008,610
Income from continuing operations | 28,885 |  | 27,932 |  | 58,709 | 44,755
Nonregulated operation | Other |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 28 |  | (112) |  | 45 | (94)
Income from continuing operations | 1,098 |  | (1,256) |  | (1,624) | (5,442)
Nonregulated operation | Intersegment eliminations |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 4,467 |  | 3,984 |  | 9,135 | 9,505
Nonregulated operation | Intersegment eliminations | Pipeline |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 167 |  | 142 |  | 407 | 158
Nonregulated operation | Intersegment eliminations | Construction materials and contracting |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 142 |  | 90 |  | 204 | 152
Nonregulated operation | Intersegment eliminations | Construction services |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | 797 |  | 779 |  | 1,839 | 3,249
Nonregulated operation | Intersegment eliminations | Other |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |
Revenues | $ 3,361 |  | $ 2,973 |  | $ 6,685 | $ 5,946

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
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- Details
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Namespace Prefix: |
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Period Type: |

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Period Type: |

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- Details
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Namespace Prefix: |
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- Details
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