Credit Facility - Narrative (Details)
Sep. 01, 2017
USD ($)
Jul. 31, 2020
Apr. 30, 2018
Aug. 31, 2017
USD ($)
Minimum | Revolving Credit Facility        
Line of Credit Facility [Line Items]        
Commitment fee percentage on unused portion of the Facility 0.20%      
Maximum | Revolving Credit Facility        
Line of Credit Facility [Line Items]        
Commitment fee percentage on unused portion of the Facility 0.35%      
Prior Credit Facility | Revolving Credit Facility | Line of Credit        
Line of Credit Facility [Line Items]        
Line of credit facility, borrowing capacity       $ 800,000,000.0
Credit Facility        
Line of Credit Facility [Line Items]        
Debt Instrument, term 5 years      
Weighted average interest rate     4.02%  
Deferred financing costs $ 18,700,000      
Credit Facility | Line of Credit        
Line of Credit Facility [Line Items]        
Deferred financing costs 5,200,000      
Credit Facility | Term Loan        
Line of Credit Facility [Line Items]        
Debt instrument, face amount 800,000,000.0      
Deferred financing costs 13,400,000      
Credit Facility | Revolving Credit Facility | Line of Credit        
Line of Credit Facility [Line Items]        
Line of credit facility, borrowing capacity 900,000,000.0      
Borrowing capacity after initial year of term 800,000,000.0      
Credit Facility | Standby Letters of Credit        
Line of Credit Facility [Line Items]        
Line of credit facility, borrowing capacity 300,000,000.0      
Credit Facility | Swing Line Loan        
Line of Credit Facility [Line Items]        
Line of credit facility, borrowing capacity $ 75,000,000.0      
Credit Facility | Minimum        
Line of Credit Facility [Line Items]        
Fixed charge coverage ratio 1.50      
Credit Facility | Maximum        
Line of Credit Facility [Line Items]        
Leverage ratio 4.75      
Leverage ratio election option for four fiscal quarters in event of material acquisition 3.75      
Credit Facility | Maximum | Forecast        
Line of Credit Facility [Line Items]        
Leverage ratio   3.50    
Credit Facility | Eurodollar | Minimum        
Line of Credit Facility [Line Items]        
Basis spread on variable rate 1.00%      
Credit Facility | Eurodollar | Maximum        
Line of Credit Facility [Line Items]        
Basis spread on variable rate 2.25%      
Credit Facility | Base Rate | Minimum        
Line of Credit Facility [Line Items]        
Basis spread on variable rate 0.00%      
Credit Facility | Base Rate | Maximum        
Line of Credit Facility [Line Items]        
Basis spread on variable rate 1.25%