Stock-Based Compensation - Additional Information (Detail) (USD $)	9 Months Ended
	Sep. 24, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, options outstanding	3,554,926
Common stock, options vested	2,161,184
Common stock, options unvested	1,393,742
Stock options exercised	739
Unrecognized compensation expense, recognition period	1 year 2 months 12 days
Unrecognized compensation expense	$ 2,300,000
Non Executive Employees [Member] | Initial Public Offering [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase common stock granted	223,183
Stock options exercise price	$ 15.00
Unrecognized compensation expense	1,300,000
Unrecognized compensation expense, recognition period	4 years
Premium Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, options outstanding	2,062,442
Restricted Grants [Member] | Initial Public Offering [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of directors granted shares	2
Restricted Grants [Member] | Directors [Member] | Initial Public Offering [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares granted	3,333
Value of restricted grants	50,000
Vesting period of shares	3 years
Stock-based compensation expense to be incurred, restricted grants	$ 330,000