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Commitments and Contingencies (Narrative) (Details) - USD ($) |  |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | --- | ---
Apr. 24, 2023 | Apr. 11, 2022 | Jun. 30, 2023 | Jun. 30, 2023
Commitments And Contingencies [Line Items] |  |  |  |
Outstanding performance bonds |  |  | $ 865,428,000 | $ 865,428,000
Revenue value remaining from outstanding performance bonds |  |  | 371,275,000 | 371,275,000
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 |
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 | $ 1,000,000
Warranty periods |  |  |  | 1 year
Maximum [Member] |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Bids bond range |  |  | $ 10,000,000 | $ 10,000,000
Warranty periods |  |  |  | 3 years

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