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Summary of Significant Accounting Policies - Unsatisfied Performance Obligations (Details) $ in Millions	Dec. 31, 2025 USD ($)
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

Revenue Remaining Performance Obligation Percentage Year 1

+ References

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- Definition

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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

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