Annual report pursuant to Section 13 and 15(d)

Organization and Significant Accounting Policies - Additional Information 1 (Detail)

v3.10.0.1
Organization and Significant Accounting Policies - Additional Information 1 (Detail)
12 Months Ended
Sep. 29, 2018
USD ($)
Companies
Sep. 30, 2017
USD ($)
Sep. 24, 2016
USD ($)
New Accounting Pronouncement, Early Adoption [Line Items]      
Number of unconsolidated companies | Companies 9    
Equity income (loss) $ 2,800,000 $ 900,000 $ (400,000)
Investment in unconsolidated companies 18,500,000 9,200,000  
Excess loss insurance that covers any health care claims 700,000    
Stock-based compensation 11,602,000 11,115,000 8,356,000
Stock-based compensation after tax 8,400,000 7,000,000 5,300,000
Restricted cash $ 10,899,000 12,645,000 $ 10,900,000
Minimum      
New Accounting Pronouncement, Early Adoption [Line Items]      
Owned percentage in unconsolidated entities (as percent) 13.00%    
General liability and vehicle liability insurance policies $ 250,000    
Maximum      
New Accounting Pronouncement, Early Adoption [Line Items]      
Owned percentage in unconsolidated entities (as percent) 50.00%    
General liability and vehicle liability insurance policies $ 350,000    
Other income (expense) | Purishield LLC and Ceregenin LLC      
New Accounting Pronouncement, Early Adoption [Line Items]      
Non-cash impairment charge   $ 16,600,000