Investments in Affiliates - Summarized Balance Sheet Information for Equity Method Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Schedule of Equity Method Investments [Line Items]
Current assets	$ 1,695,050	$ 1,347,296
Total assets	2,580,321	2,167,933
Current liabilities	1,056,476	797,594
Granite’s share of net assets	91,101	80,725
Equity Method Investment, Nonconsolidated Investee or Group of Investees
Schedule of Equity Method Investments [Line Items]
Current assets	207,838	194,210
Noncurrent assets	163,121	172,560
Total assets	370,959	366,770
Current liabilities	90,889	106,780
Long-term liabilities	58,202	59,356
Total liabilities	149,091	166,136
Net assets	$ 221,868	$ 200,634