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Commitments and Contingencies (Narrative) (Details) - USD ($) |  |  | 9 Months Ended
--- | --- | --- | ---
Apr. 24, 2023 | Apr. 11, 2022 | Sep. 30, 2023
Commitments And Contingencies [Line Items] |  |  |
Outstanding performance bonds |  |  | $ 1,073,863,000
Revenue value remaining from outstanding performance bonds |  |  | 594,903,000
Proceeds from legal settlements |  |  | 1,930,000
One-time payment amount | $ 1,250,000 |  |
Disbursement amount from litigation escrow account | 680,000 |  |
Expected funds to be released in connection with pre-purchase construction project | $ 800,000 |  |
Benefit in cost of contract revenues |  |  | 2,410,000
Other income related to settlement |  |  | 784,000
Litigation settlement amount yet to released |  |  | 800,000
Indemnification Commitment [Member] |  |  |
Commitments And Contingencies [Line Items] |  |  |
Aggregate demolition surety performance bond |  | $ 21,934,000 |
Minimum [Member] |  |  |
Commitments And Contingencies [Line Items] |  |  |
Bids bond range |  |  | $ 1,000,000
Warranty periods |  |  | 1 year
Maximum [Member] |  |  |
Commitments And Contingencies [Line Items] |  |  |
Bids bond range |  |  | $ 10,000,000
Warranty periods |  |  | 3 years

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