v3.26.1
Long-Term Debt (Narrative) (Details) - USD ($)
1 Months Ended 3 Months Ended 9 Months Ended
Dec. 31, 2019
Jun. 30, 2021
Sep. 30, 2017
Jun. 27, 2026
Jun. 28, 2025
Jun. 27, 2026
Jun. 28, 2025
Dec. 31, 2010
Debt Instrument [Line Items]                
Property and equipment with undepreciated cost pledge as collateral for long term debt       $ 234,700,000   $ 234,700,000    
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]           us-gaap:SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember    
Line of Credit [Member]                
Debt Instrument [Line Items]                
Line of credit facility borrowing capacity       150,000,000.0   $ 150,000,000.0    
Debt maturity date           Jun. 01, 2030    
Letter of Credit [Member]                
Debt Instrument [Line Items]                
Line of credit facility borrowing capacity       10,000,000.0   $ 10,000,000.0    
Borrowings outstanding       900,000   900,000    
Cash Flow Hedging [Member]                
Debt Instrument [Line Items]                
Other comprehensive income (loss), net of income taxes       (42,200) $ (1,100,000) (232,600) $ (600,000)  
Unrealized gains included in other assets       7,100,000 $ 8,200,000 7,100,000 $ 8,200,000  
Interest Rate Swap [Member]                
Debt Instrument [Line Items]                
Derivative notional amount       103,300,000   103,300,000    
Senior Notes, Maturing 2031 [Member]                
Debt Instrument [Line Items]                
Debt instrument principal amount   $ 350,000,000.0            
Debt instrument stated interest rate   4.00%            
Maturity period of senior notes   2031            
Secured Debt Maturing October 2027 [Member]                
Debt Instrument [Line Items]                
Debt maturity date     Oct. 01, 2027          
Secured borrowing     $ 60,000,000          
Secured Debt Maturing October 2027 [Member] | Interest Rate Swap [Member]                
Debt Instrument [Line Items]                
Derivative notional amount       $ 8,000,000.0   $ 8,000,000.0    
Derivative, fixed interest rate       3.962%   3.962%    
Monthly principal amortization           $ 500,000    
Derivative maturity date           Oct. 01, 2027    
Debt instrument variable interest rate           1.75%    
Secured Debt Maturing January 2030 [Member]                
Debt Instrument [Line Items]                
Debt instrument principal amount $ 155,000,000              
Debt maturity date Jan. 01, 2030              
Secured Debt Maturing January 2030 [Member] | Interest Rate Swap [Member]                
Debt Instrument [Line Items]                
Derivative, fixed interest rate       2.998%   2.998%    
Monthly principal amortization           $ 650,000    
Debt instrument variable interest rate           1.60%    
Recovery Zone Facility Bonds [Member]                
Debt Instrument [Line Items]                
Debt maturity date           Jan. 01, 2036    
Annual amount of redemption of bonds       $ 4,500,000   $ 4,500,000    
Mandatory bonds redemption beginning period           Jan. 01, 2014    
Mandatory bonds redemption period end date           Dec. 17, 2029    
Total amount of bonds funded       $ 40,900,000   $ 40,900,000   $ 99,700,000