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Revenue from contracts with customers - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |  |
Construction contractor, contract cost, subject to uncertainty, amount | $ 31.2 |  | $ 31.2 |
Contract with customer, liability, revenue recognized | 47.4 | $ 6.3 | 169.0 | $ 164.3
Amounts from performance obligations satisfied in prior periods | 25.8 | $ 20.2 | 71.8 | $ 41.7
Remaining performance obligation, amount | 3,500.0 |  | 3,500.0 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-10-01 |  |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |  |
Remaining performance obligation, amount | $ 2,300.0 |  | $ 2,300.0 |
Revenue, remaining performance obligation, expected timing of satisfaction, period | 12 months |  | 12 months |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-10-01 |  |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |  |
Remaining performance obligation, amount | $ 681.1 |  | $ 681.1 |
Revenue, remaining performance obligation, expected timing of satisfaction, period | 12 months |  | 12 months |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-10-01 |  |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |  |
Remaining performance obligation, amount | $ 551.1 |  | $ 551.1 |
Revenue, remaining performance obligation, expected timing of satisfaction, period |  |  |  |
Construction services |  |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |  |
Contract with customer, term (less than) | 2 years |  | 2 years |
Pipeline |  |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |  |
Contract with customer, term (less than) | 12 months |  | 12 months |
Pipeline | Firm Transportation Contract |  |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |  |
Contract weighted average remaining duration (less than) | 5 years |  | 5 years |
Pipeline | Firm Storage Contract |  |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |  |
Contract weighted average remaining duration (less than) | 2 years |  | 2 years |

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- Definition Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 606 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479806/606-10-50-8 + Details
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- Definition Amount of revenue recognized from performance obligation satisfied or partially satisfied in previous reporting periods. Includes, but is not limited to, change in transaction price. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 606 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 12A -Publisher FASB -URI https://asc.fasb.org/1943274/2147479806/606-10-50-12A + Details
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- Definition Amount of transaction price allocated to performance obligation that has not been recognized as revenue. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (a) -SubTopic 10 -Topic 606 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479806/606-10-50-13 + Details
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- Definition Amount of cost incurred on construction contract for unapproved change order, claim, or similar item subject to uncertainty. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 910 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482332/910-20-50-1 + Details
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