Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies - Insurance and Revenues (Details)

v3.8.0.1
Summary of Significant Accounting Policies - Insurance and Revenues (Details)
 1 Months Ended 3 Months Ended 9 Months Ended 12 Months Ended
May 02, 2017
USD ($)
$ / shares
shares
Nov. 24, 2016
derivative
Sep. 28, 2017
USD ($)
Sep. 29, 2016
USD ($)
Sep. 28, 2017
USD ($)
Sep. 29, 2016
USD ($)
Dec. 26, 2013
derivative
Dec. 29, 2016
USD ($)
Jan. 01, 2016
USD ($)
Self-Insurance Reserves                  
Maximum loss before additional coverage applies         $ 7,000,000        
Derivative Financial Instruments                  
Cash flow hedge ineffectiveness during the period         0 $ 0      
Revenue Recognition and Gift Cards                  
Gift card breakage income         568,000 452,000      
Sales Returns and Allowances                  
Allowance for sales returns     $ 6,892,000   6,892,000     $ 4,887,000  
Advertising and Pre-opening Expense                  
Pre-opening expenses     6,700,000 $ 5,046,000 13,825,000 10,989,000      
Loss on Early Extinguishment of Debt Abstract                  
Common stock, par value | $ / shares $ 0.001                
Payments on term loans $ 192,000,000       196,625,000 900,000      
Loss on extinguishment of debt     $ 0 $ 0 (5,442,000) (153,000)      
Selling and store operating expenses and pre-opening expenses                  
Advertising and Pre-opening Expense                  
Advertising expense         $ 31,938,000 $ 25,404,000      
Interest Rate Cap                  
Derivative Financial Instruments                  
Number of derivatives designated cash flow hedges entered into during period | derivative   2              
Interest Rate Swap                  
Derivative Financial Instruments                  
Number of derivatives designated cash flow hedges entered into during period | derivative             2    
Minimum                  
Advertising and Pre-opening Expense                  
Period prior to store opening or relocation that pre-opening expenses begin         3 months        
Stock-Based Compensation                  
Period of vesting provision         3 years        
Maximum                  
Revenue Recognition and Gift Cards                  
Number of days customers may store merchandise         14 days        
Advertising and Pre-opening Expense                  
Period prior to store opening or relocation that pre-opening expenses begin         6 months        
Stock-Based Compensation                  
Period of vesting provision         5 years        
Retained Earnings [Member] | Accounting Standards Update 2016-09 [Member]                  
Stock-Based Compensation                  
Cumulative effect of adoption                 $ (148,000)
Additional Paid-in Capital [Member] | Accounting Standards Update 2016-09 [Member]                  
Stock-Based Compensation                  
Cumulative effect of adoption                 $ 238,000
IPO                  
Loss on Early Extinguishment of Debt Abstract                  
Number of shares issued | shares 10,147,025                
Net proceeds $ 192,000,000