Accrued Liabilities (Tables)

12 Months Ended

Dec. 31, 2017

Accrued Liabilities, Current [Abstract]

Summary of Accrued Liabilities

Accrued liabilities consist of the following at December 31:

	2017		2016
Accrued wages, bonuses and commissions	$	43,688	$	38,996
Other accrued liabilities	20,987		16,993
	$	64,675	$	55,989