Quarterly report pursuant to Section 13 or 15(d)

Stock Based Compensation - Equity Incentive Plan - Additional Information (Detail)

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Stock Based Compensation - Equity Incentive Plan - Additional Information (Detail) - USD ($)
 3 Months Ended
Apr. 10, 2015
Mar. 27, 2014
Mar. 10, 2014
Mar. 31, 2018
Dec. 28, 2017
May 19, 2016
Mar. 06, 2014
Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Employee contribution through payroll withholdings       $ 200,935        
Performance Share Units [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Share-based compensation arrangement by share-based payment award, number of shares authorized 1,310,104              
Employee Stock Purchase Plan [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Share-based compensation arrangement by share-based payment award, number of shares available for grant       405,921        
Lowest percentage of annual compensation to be utilized by an employee for the plan 1.00%              
Highest percentage of annual compensation to be utilized by an employee for the plan 10.00%              
Maximum number of shares permitted to purchase 7,500              
Offering period 6 months              
Exercise price discount from fair value on offering date 85.00%              
Exercise price discount from fair value on exercise date 85.00%              
Share-based compensation arrangement by share-based payment award, terms of award       On April 10, 2015, the Company’s Board approved the ESPP, under which shares of common stock were reserved for purchase by the Company’s employees, subject to approval by the stockholders. On May 21, 2015, the Company’s stockholders approved the ESPP. Employees may designate an amount not less than 1% but not more than 10% of their annual compensation, but for not more than 7,500 shares during an offering period. An offering period shall be six months in duration commencing on or about January 1 and July 1 of each year. The exercise price of the option will be the lesser of 85% of the fair market of the common stock on the first business day of the offering period and 85% of the fair market value of the common stock on the applicable exercise date.        
2013 Equity Incentive Plan [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Share-based compensation arrangement by share-based payment award, number of shares authorized           4,485,967   1,042,167
Percentage of total number of shares to be issued under incentive plan     18.00%          
Share-based compensation arrangement by share-based payment award, other share increase (decrease)   2,335,967            
Common stock, capital shares reserved for future issuance           2,150,000    
Common stock to be issued       404,215        
Share-based compensation arrangement by share-based payment award, number of shares available for grant       31,951        
Non-Employee Equity Compensation Plan 2014 [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Share-based compensation arrangement by share-based payment award, number of shares authorized           600,000 250,000  
Common stock, capital shares reserved for future issuance           350,000    
Common stock available to be issued       157,439        
2017 Equity Inducement Plan [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Common stock available to be issued       434,000        
2017 Equity Inducement Plan [Member] | Restricted Stock Units (RSUs) [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Common stock, capital shares reserved for future issuance         600,000