Revenue Recognition - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
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 20 months. For product revenues and freight revenues, customer payment terms are generally 30 days from invoice date. Customer payments for the paving operations are based on a contractual billing schedule and are due 30 days from invoice date.
Product and freight revenues customer payment terms	30 days
Customer payments term based on contractual billing	30 days
Future revenues from unsatisfied performance obligations	$ 88,054,000	$ 145,921,000
Revenue recognized from contract liabilities	4,199,000	3,835,000
Retainage on contracts	4,824,000	5,759,000	$ 9,029,000
Colorado
Revenue Recognition [Line Items]
Service revenues	$ 11,143,000	$ 16,000,000
Minimum
Revenue Recognition [Line Items]
Performance obligations, customer satisfaction period	1 day	1 day
Construction contracts warranty provisions period	9 months
Maximum
Revenue Recognition [Line Items]
Performance obligations, customer satisfaction period	20 months	11 months
Construction contracts warranty provisions period	1 year