v3.26.1
Construction Joint Ventures - Schedule of Unconsolidated Construction Joint Ventures Revenue and Costs (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Guarantor Obligations [Line Items]        
Cost of revenue $ 1,217,101 $ 926,865 $ 2,019,661 $ 1,542,563
Changes to net income (loss) (271,584) 80,345 (307,973) 52,018
Granite’s interest in net income (loss)     (13,096) (3,814)
Collaborative Arrangement        
Guarantor Obligations [Line Items]        
Revenue 16,447 5,963 17,930 10,881
Cost of revenue 5,021 3,735 5,691 7,685
Granite’s interest in gross profit 11,426 2,228 12,239 3,196
Granite’s interest in net income (loss) 11,709 2,597 13,096 3,814
Collaborative Arrangement | Corporate Joint Venture        
Guarantor Obligations [Line Items]        
Revenue 8,598 (411) 15,281 3,661
Cost of revenue 7,252 15,286 10,541 32,820
Changes to net income (loss) 2,338 (14,511) 6,762 (26,972)
Collaborative Arrangement | Co-venturer | Other Partners Interest in Partnerships        
Guarantor Obligations [Line Items]        
Revenue (7,849) (6,374) (2,649) (7,220)
Cost of revenue 2,231 11,551 4,850 25,135
Changes to net income (loss) $ (9,371) $ (17,108) $ (6,334) $ (30,786)