Segment Information - Schedule of Selected Information for Each Business Segment (Detail) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Mar. 30, 2017	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Segment Reporting Information [Line Items]
Revenues		$ 88,837	$ 77,966	$ 170,196	$ 154,440
Operating income
Operating income		17,897	14,179	29,824	31,852
Interest expense		4,285	6,983	9,705	14,008
Loss on extinguishment of debt	$ 2,200			2,161
Other income		(552)	(401)	(1,129)	(466)
Income before income taxes		14,164	7,597	19,087	18,310
Operating Segments [Member] | U.S. [Member]
Segment Reporting Information [Line Items]
Revenues		78,100	65,134	149,127	130,067
Operating income
Operating income		16,895	12,895	28,063	24,293
Operating Segments [Member] | International [Member]
Segment Reporting Information [Line Items]
Revenues		10,737	12,832	21,069	24,373
Operating income
Operating income		$ 1,002	$ 1,284	$ 1,761	$ 7,559