Share-based Compensation - Stock Option Activity (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Jan. 02, 2016	Jan. 03, 2015	Dec. 28, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercised, Shares			0
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning balance, Shares	1,757,000	1,221,000	830,000
Options granted, Shares	2,976,000	684,000	441,000
Options exercised, Shares	(238,000)	(113,000)
Options forfeited or expired, Shares	(21,000)	(35,000)	(50,000)
Ending balance, Shares	4,474,000	1,757,000	1,221,000	830,000
Exercisable shares, Ending balance	850,000
Beginning balance, Weighted average exercise price	$ 8.50	$ 7.77	$ 8.17
Vested or expected to vest at December 31, 2016	4,474,000
Granted, Weighted average exercise price	$ 11.15	9.22	8.00
Options exercised, Weighted average exercise price	7.29	4.94
Forfeited or expired, Weighted average exercise price	9.99	8.56	16.45
Ending balance, Weighted average exercise price	10.32	$ 8.50	$ 7.77	$ 8.17
Exercisable at December 31, 2016, Weighted average exercise price	$ 8.27
Beginning balance, Aggregate intrinsic value	$ 4,373,800	$ 400,700		$ 811,900
Vested or expected to vest at December 31, 2016, Weighted average exercise price	$ 10.32
Beginning balance, Weighted average contractual term (years)	8 years 9 months 18 days	8 years	7 years 7 months 6 days	7 years 7 months 6 days
Exercisable at December 31, 2016, Weighted average contractual term (years)	6 years 6 months
Vested or expected to vest at December 31, 2016, Weighted average contractual term (years)	8 years 9 months 18 days
Exercised, Aggregate intrinsic value	$ 2,304,700	$ 637,400
Ending balance, Aggregate intrinsic value	5,623,300	$ 4,373,800	$ 400,700
Exercisable at December 31, 2016, Aggregate intrinsic value	2,598,600
Vested or expected to vest at December 31, 2016, Aggregate intrinsic value	$ 5,623,300