Significant Accounting Policies - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2018 Facility State Segment
Significant Accounting Policies [Line Items]
Number of states with aggregates business sales by destination | State	30
Number of reportable segments | Segment	3
Minimum [Member]
Significant Accounting Policies [Line Items]
Number of quarries and yards | Facility	300