Segment Information - Schedule of Selected Information for Each Business Segment (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Revenues
Revenues	$ 76,474	$ 74,823
Revenues	76,474	74,823
Operating income
Operating income	17,673	11,378
Interest expense, net	(7,018)	(10,623)
Other income (expense), net	58	(383)
Income before income taxes	10,713	372
Total assets
Assets	249,263		$ 242,379
U.S. [Member]
Revenues
Revenues	64,933	60,667
Revenues	64,933	60,667
Total assets
Assets	232,217		222,926
International [Member]
Revenues
Revenues	11,541	14,156
Revenues	11,541	14,156
Total assets
Assets	17,046		$ 19,453
Operating Segments [Member]
Revenues
Revenues	82,311	79,944
Revenues	82,311	79,944
Operating income
Operating income	17,538	11,205
Operating Segments [Member] | U.S. [Member]
Revenues
Revenues	70,770	65,788
Revenues	70,770	65,788
Operating income
Operating income	13,403	12,679
Operating Segments [Member] | International [Member]
Revenues
Revenues	11,541	14,156
Revenues	11,541	14,156
Operating income
Operating income	4,135	(1,474)
Inter-Segment [Member]
Revenues
Revenues	(5,837)	(5,121)
Revenues	(5,837)	(5,121)
Operating income
Operating income	$ 135	$ 173