Accounts Receivable - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2015 USD ($) mo	Dec. 31, 2014 USD ($)
Accounts Notes And Loans Receivable [Line Items]
Retainages expected to be collected in 2017	$ 145,000,000
Retainages expected to be collected in 2018	10,000,000
Allowance for doubtful accounts	$ 0	$ 0
Maximum [Member]
Accounts Notes And Loans Receivable [Line Items]
Employee receivables expected collection months | mo	12