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Summary of Significant Accounting Policies - Unsatisfied Performance Obligations (Details) $ in Millions | Dec. 31, 2025 USD ($)
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Utility and related structures | Engineered Structures |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Unsatisfied performance obligations, Amount | $ 434.9
Percent expected to be delivered in 2026 | 95.00%
Wind towers | Engineered Structures |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Unsatisfied performance obligations, Amount | $ 627.8
Percent expected to be delivered in 2026 | 42.00%
Percent expected to be delivered in 2027 | 53.00%
Inland barges | Transportation Products |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Unsatisfied performance obligations, Amount | $ 296.9

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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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