Accounts Payable and Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2017

Payables and Accruals [Abstract]

Schedule of Accounts Payable and Accrued Expenses

Accounts payable and accrued expenses consisted of the following (in thousands): 

	December 31,
	2017		2016
Trade accounts payable	$	24,189	$	14,534
Accrued salaries, vacation and benefits	22,205		18,049
Other accrued expenses	26,256		23,379
Accrued contingent consideration	2,724		3,590
Negative cash book balance	2,906		5,044
	$	78,280	$	64,596