Segment Information - Schedule of Selected Information for Each Business Segment (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Revenues
Revenues	$ 74,123	$ 75,682	$ 222,260	$ 224,631
Operating income
Operating income	13,408	9,221	30,142	27,690
Interest expense, net	(7,100)	(10,585)	(31,599)	(31,704)
Loss on extinguishment of debt			(15,528)
Other income (expense), net	(183)	441	234	(148)
Income (loss) before income taxes	6,125	(923)	(16,751)	(4,162)
Total assets
Assets	236,132		236,132		$ 243,153
U.S. [Member]
Revenues
Revenues	59,212	59,429	178,257	174,808
Total assets
Assets	214,579		214,579		219,129
International [Member]
Revenues
Revenues	14,911	16,253	44,003	49,823
Total assets
Assets	21,553		21,553		$ 24,024
Operating Segments [Member]
Revenues
Revenues	79,331	80,564	238,900	238,502
Operating income
Operating income	13,305	9,183	30,011	27,264
Operating Segments [Member] | U.S. [Member]
Revenues
Revenues	64,420	64,311	194,897	188,679
Operating income
Operating income	13,303	8,174	29,424	23,611
Operating Segments [Member] | International [Member]
Revenues
Revenues	14,911	16,253	44,003	49,823
Operating income
Operating income	2	1,009	587	3,653
Inter-Segment [Member]
Revenues
Revenues	(5,208)	(4,882)	(16,640)	(13,871)
Operating income
Operating income	$ 103	$ 38	$ 131	$ 426