Accounts Payable and Accrued Expenses - Summary of Accounts Payable and Accrued Expenses (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Payables And Accruals [Abstract]
Trade accounts payable, including due to subcontractors	$ 53,075	$ 45,409
Compensation and related benefits	5,710	5,246
Current portion of earnout liability	1,198	2,989
Accrued warranty	3,456	4,464
Contract liabilities	5,743	1,676
Other accrued expenses	10,170	11,002
Total accounts payable and accrued expenses	$ 79,352	$ 70,786

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits.

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Carrying value as of the balance sheet date of obligations incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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