Revenues and Gross Profit - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Revenue Recognition [Line Items]
Performance obligations, description of timing			Performance obligations within paving service agreements are satisfied over time, primarily ranging from one day to two years. Customer payments for the paving operations are based on a contractual billing schedule and are typically "paid-when-paid", meaning the Company is paid once the customer is paid.
Future revenues from unsatisfied performance obligations	$ 252	$ 377	$ 252	$ 377
Service revenues	1,811	1,764	3,164	3,015
Service | CALIFORNIA and COLORADO | West Group
Revenue Recognition [Line Items]
Service revenues	$ 102	$ 117	$ 137	$ 143
Minimum | Service
Revenue Recognition [Line Items]
Performance obligations, period			1 day
Maximum | Service
Revenue Recognition [Line Items]
Performance obligations, period			2 years