Annual report pursuant to Section 13 and 15(d)

Financing Agreements - Narrative (Details)

v3.19.3
Financing Agreements - Narrative (Details)
12 Months Ended
Dec. 15, 2014
USD ($)
Jul. 09, 2010
USD ($)
Sep. 30, 2019
USD ($)
Rate
Sep. 30, 2018
USD ($)
Sep. 30, 2017
USD ($)
Sep. 25, 2019
USD ($)
Jul. 12, 2019
USD ($)
Sep. 30, 2018
EUR (€)
Long-term Debt                
Total debt     $ 619,500,000 $ 344,600,000        
Less: current portion     0 0        
Total long-term debt     619,500,000 344,600,000        
Maturities of long-term debt                
2020     150,000,000.0          
2021     0          
2022     0          
2023     0          
2024     $ 0          
Debt Instrument [Line Items]                
LeverageHolidayBusinessAcquisition     75,000,000.0          
Debt Instrument, Covenant Holiday, Maximum Ratio of Indebtedness to Earnings before Interest, Taxes, Depreciation, and Amortization     4.0          
Debt Instrument, Covenant Terms, Maximum Ratio of Indebtedness to Earnings before Interest, Taxes, Depreciation, and Amortization     3.5          
Debt Instrument, Covenant Terms, Minimum Ratio of Earnings before Interest, Taxes, Depreciation, and Amortization to Interest Expense     3.0          
$375 senior unsecured notes                
Long-term Debt                
Total debt     $ 370,100,000 0   $ 374,400,000    
Debt Instrument [Line Items]                
Debt issued           $ 375,000,000.0    
Debt Issuance Costs, Line of Credit Arrangements, Gross     4,300,000          
Stated interest rate           4.50%    
Notes issued at a discount           $ 0.6    
Effective annual interest rate (as a percent)           4.53%    
Debt Issuance Costs, Net     4,300,000          
$150 senior unsecured notes                
Long-term Debt                
Total debt   $ 148,400,000 149,700,000 149,300,000        
Debt Instrument [Line Items]                
Debt issued   150,000,000            
Deferred financing costs   $ 200,000            
Stated interest rate   5.50%            
Notes issued at a discount   $ 1,600,000            
Effective annual interest rate (as a percent)   5.65%            
Percentage of the principal amount at which the notes are redeemable due to a change of control   101.00%            
Debt Issuance Costs, Net     200,000 400,000        
$100 Series A Notes (3)                
Long-term Debt                
Total debt     99,700,000 99,600,000        
Debt Instrument [Line Items]                
Debt issued $ 100,000,000.0              
Deferred financing costs $ 300,000              
Stated interest rate 4.60%              
Redemption price, percentage 100.00%              
Debt Issuance Costs, Net     300,000 400,000        
$900 revolving credit facility                
Long-term Debt                
Total debt     0 95,700,000        
Debt Instrument [Line Items]                
Maximum borrowing capacity available under the facility     900,000,000 $ 900,000,000.0 $ 700,000,000.0      
Letters of credit outstanding     7,100,000          
Accordion option to increase commitments under the unsecured revolving credit facility     450,000,000          
Current borrowing capacity available under the facility     892,900,000          
Prior Debt Issuance Costs, Gross     2,000,000.0          
Debt Issuance Costs, Line of Credit Arrangements, Gross     $ 1,100,000          
Weighted average interest rates (as a percent)     2.54% 1.83% 1.40%      
Weighted average facility fee (as a percent)     0.12% 0.15% 0.23%      
$500 Term Loan                
Debt Instrument [Line Items]                
Debt issued     $ 500,000,000          
Term Loan Ticking Fee     0.15%          
$225 Term Loan                
Debt Instrument [Line Items]                
Debt issued     $ 225,000,000          
$180 term loan                
Debt Instrument [Line Items]                
Debt issued     180,000,000.0          
Weighted average interest rates (as a percent)       2.60%        
Syndicated Credit Facility                
Debt Instrument [Line Items]                
Letters of credit outstanding | €               € 150,000,000.0
Deferred financing costs       $ 1,100,000        
Bridge Facility                
Debt Instrument [Line Items]                
Deferred financing costs             $ 5,600,000  
Bridge Loan             $ 1,100,000,000  
Other Credit Arrangements                
Debt Instrument [Line Items]                
Maximum borrowing capacity available under the facility     305,700,000          
Amount of credit facility utilized for providing bank guarantees     252,200,000          
Debt Instrument, Redemption, Period One [Member] | $500 Term Loan                
Debt Instrument [Line Items]                
Debt Instrument, Periodic Payment, Principal     0.05          
Debt Instrument, Redemption, Period One [Member] | $225 Term Loan                
Debt Instrument [Line Items]                
Debt Instrument, Periodic Payment, Principal     0.05          
Debt Instrument, Redemption, Period Three [Member] | $500 Term Loan                
Debt Instrument [Line Items]                
Debt Instrument, Periodic Payment, Principal     0.075          
Debt Instrument, Redemption, Period Three [Member] | $225 Term Loan                
Debt Instrument [Line Items]                
Debt Instrument, Periodic Payment, Principal     0.075          
Debt Instrument, Redemption, Period Five [Member] | $500 Term Loan                
Debt Instrument [Line Items]                
Debt Instrument, Periodic Payment, Principal     $ 0.10          
LIBO Rate [Member] | $500 Term Loan | Maximum                
Debt Instrument [Line Items]                
Debt Instrument, Basis Spread on Variable Rate | Rate     1.75%          
LIBO Rate [Member] | $500 Term Loan | Minimum                
Debt Instrument [Line Items]                
Debt Instrument, Basis Spread on Variable Rate | Rate     1.00%          
LIBO Rate [Member] | $225 Term Loan | Maximum                
Debt Instrument [Line Items]                
Debt Instrument, Basis Spread on Variable Rate | Rate     1.625%          
LIBO Rate [Member] | $225 Term Loan | Minimum                
Debt Instrument [Line Items]                
Debt Instrument, Basis Spread on Variable Rate | Rate     0.875%          
Base Rate [Member] | $500 Term Loan | Maximum                
Debt Instrument [Line Items]                
Debt Instrument, Basis Spread on Variable Rate | Rate     0.75%          
Base Rate [Member] | $500 Term Loan | Minimum                
Debt Instrument [Line Items]                
Debt Instrument, Basis Spread on Variable Rate | Rate     0.00%          
Base Rate [Member] | $225 Term Loan | Maximum                
Debt Instrument [Line Items]                
Debt Instrument, Basis Spread on Variable Rate | Rate     0.625%          
Base Rate [Member] | $225 Term Loan | Minimum                
Debt Instrument [Line Items]                
Debt Instrument, Basis Spread on Variable Rate | Rate     0.00%