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v3.23.1

Goodwill rollforward (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022
Goodwill [Roll Forward] |  |  |
Balance at beginning of period | $ 763,500 | $ 765,386 | $ 765,386
Goodwill acquired during the year | 0 | 0 | 238
Measurement period adjustments | 0 | (2,124) | (2,124)
Balance at end of period | 763,500 | 763,262 | 763,500
Natural gas distribution |  |  |
Goodwill [Roll Forward] |  |  |
Balance at beginning of period | 345,736 | 345,736 | 345,736
Goodwill acquired during the year | 0 | 0 | 0
Measurement period adjustments | 0 | 0 | 0
Balance at end of period | 345,736 | 345,736 | 345,736
Construction materials and contracting |  |  |
Goodwill [Roll Forward] |  |  |
Balance at beginning of period | 274,540 | 276,426 | 276,426
Goodwill acquired during the year | 0 | 0 | 238
Measurement period adjustments | 0 | (2,124) | (2,124)
Balance at end of period | 274,540 | 274,302 | 274,540
Construction services |  |  |
Goodwill [Roll Forward] |  |  |
Balance at beginning of period | 143,224 | 143,224 | 143,224
Goodwill acquired during the year | 0 | 0 | 0
Measurement period adjustments | 0 | 0 | 0
Balance at end of period | $ 143,224 | $ 143,224 | $ 143,224

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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 852 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481372/852-10-55-10 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 24 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482548/350-20-55-24 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(15)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482598/350-20-45-1 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482573/350-20-50-1 Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 350 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482573/350-20-50-1 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(10)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 + Details
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