Annual report pursuant to Section 13 and 15(d)

Financing Agreements (Details)

v3.10.0.1
Financing Agreements (Details)
 12 Months Ended
Dec. 15, 2014
USD ($)
Jul. 09, 2010
USD ($)
Sep. 30, 2018
USD ($)
Sep. 30, 2017
USD ($)
Mar. 24, 2016
USD ($)
Feb. 01, 2016
USD ($)
Dec. 19, 2014
USD ($)
Financing Agreements              
LeverageHolidayBusinessAcquisition     75.0        
Long-term Debt              
Total debt     $ 344,600,000 $ 465,700,000      
Less: current portion     0 18,800,000      
Total long-term debt     344,600,000 446,900,000      
Maturities of long-term debt              
2016     0        
2017     150,000,000        
2018     0        
2019     0        
2020     95,700,000        
Accordion option to increase commitments under the unsecured revolving credit facility     450.0        
Debt Issuance Costs, Line of Credit Arrangements, Gross     $ 2.1        
Debt Instrument, Covenant Terms, Maximum Ratio of Indebtedness to Earnings before Interest, Taxes, Depreciation, and Amortization     3.5        
Restricted Cash and Cash Equivalents     $ 500,000 800,000      
Debt Instrument, Covenant Terms, Minimum Ratio of Earnings before Interest, Taxes, Depreciation, and Amortization to Interest Expense     3.0        
Maximum              
Financing Agreements              
Debt Instrument, Covenant Holiday, Maximum Ratio of Indebtedness to Earnings before Interest, Taxes, Depreciation, and Amortization     4.0        
$700 revolving credit facility              
Financing Agreements              
Long-term Debt, Gross     $ 95,700,000 68,000,000      
Maturities of long-term debt              
Maximum borrowing capacity available under the facility     900.0 $ 700.0   $ 700.0 $ 700,000,000.0
Letters of credit outstanding     7,300,000        
Remaining borrowing capacity available under the credit facility     769,200,000        
Current borrowing capacity available under the facility     $ 797,000,000        
Weighted average interest rates (as a percent)     1.83% 1.40%      
Weighted average facility fee (as a percent)     0.15% 0.23%      
$180 term loan              
Financing Agreements              
Long-term Debt, Gross     $ 0 $ 148,500,000      
Maturities of long-term debt              
Debt issued     $ 180.0     $ 180.0 $ 180,000,000.0
Weighted average interest rates (as a percent)     2.60% 2.27%      
$150 senior unsecured notes              
Financing Agreements              
Long-term Debt, Gross     $ 149,700,000 $ 149,500,000      
Long-term Debt              
Total debt     $ 149,300,000 148,900,000      
Total long-term debt   $ 148,400,000          
Maturities of long-term debt              
Debt issued   150,000,000          
Deferred financing costs   $ 2,100,000          
Term of debt instrument     10 years        
Stated interest rate   5.50% 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     $ 400,000 600,000      
$100 Series A Notes (2)              
Financing Agreements              
Long-term Debt, Gross     100,000,000 100,000,000      
Long-term Debt              
Total debt     99,600,000 99,700,000      
Maturities of long-term debt              
Debt issued $ 100,000,000.0            
Deferred financing costs $ 400,000            
Private Shelf Facility, Accordion Feature, Maximum         $ 200    
Stated interest rate 4.60%            
Redemption price, percentage 100.00%            
Debt Issuance Costs, Net     400,000 300,000      
Other              
Long-term Debt              
Total debt     0 $ 600,000      
Syndicated Credit Facility              
Maturities of long-term debt              
Deferred financing costs     1.0        
Other Financing Agreements              
Maturities of long-term debt              
Maximum borrowing capacity available under the facility     248,400,000        
Amount of credit facility utilized for providing bank guarantees     196,500,000        
Interest Rate Swap [Member] | Cash Flow Hedging              
Maturities of long-term debt              
Derivative, Notional Amount     50.0        
Letter of Credit [Member]              
Maturities of long-term debt              
Letters of credit outstanding     150.0        
Scenario, Previously Reported [Member]              
Maturities of long-term debt              
Debt Issuance Costs, Line of Credit Arrangements, Gross     1.0        
Scenario, Previously Reported [Member] | Syndicated Credit Facility              
Maturities of long-term debt              
Deferred financing costs     $ 0.6