Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Schedule of financial assets and liabilities (Details)

v3.21.2
Fair Value Measurements - Schedule of financial assets and liabilities (Details) - USD ($)
$ in Millions
Jun. 30, 2021
Sep. 30, 2020
Assets:    
Cash and cash equivalents $ 476.2 $ 302.2
Investments in rabbi trust 4.7 3.9
Derivative instruments 2.6 2.6
Liabilities:    
Derivative instruments 2.3 1.6
Cash flow hedging | Foreign Exchange Forward    
Liabilities:    
Derivative, notional amount 260.5 232.8
Level 1    
Assets:    
Cash and cash equivalents 476.2 302.2
Investments in rabbi trust 4.7 3.9
Derivative instruments 0.0 0.0
Liabilities:    
Derivative instruments 0.0 0.0
Level 2    
Assets:    
Cash and cash equivalents   0.0
Investments in rabbi trust 0.0 0.0
Derivative instruments 2.6 2.6
Liabilities:    
Derivative instruments 2.3 1.6
Level 3    
Assets:    
Cash and cash equivalents 0.0 0.0
Investments in rabbi trust 0.0 0.0
Derivative instruments 0.0 0.0
Liabilities:    
Derivative instruments 0.0 0.0
2020 Notes    
Liabilities:    
Debt instruments 400.0 400.0
2020 Notes | Level 1    
Liabilities:    
Debt instruments 429.7 429.0
2020 Notes | Level 2    
Liabilities:    
Debt instruments 0.0 0.0
2020 Notes | Level 3    
Liabilities:    
Debt instruments 0.0 0.0
2019 Notes    
Liabilities:    
Debt instruments 374.6 374.5
2019 Notes | Level 1    
Liabilities:    
Debt instruments 418.2 409.0
2019 Notes | Level 2    
Liabilities:    
Debt instruments 0.0 0.0
2019 Notes | Level 3    
Liabilities:    
Debt instruments 0.0 0.0
2019 Notes    
Liabilities:    
Debt instruments 350.0  
2019 Notes | Level 1    
Liabilities:    
Debt instruments 347.8  
2019 Notes | Level 2    
Liabilities:    
Debt instruments 0.0  
2019 Notes | Level 3    
Liabilities:    
Debt instruments 0.0  
$500.0 term loan    
Liabilities:    
Debt instruments   475.0
$500.0 term loan | Level 1    
Liabilities:    
Debt instruments   0.0
$500.0 term loan | Level 2    
Liabilities:    
Debt instruments   475.0
$500.0 term loan | Level 3    
Liabilities:    
Debt instruments   0.0
$225.0 term loan    
Liabilities:    
Debt instruments   213.7
$225.0 term loan | Level 1    
Liabilities:    
Debt instruments   0.0
$225.0 term loan | Level 2    
Liabilities:    
Debt instruments   213.7
$225.0 term loan | Level 3    
Liabilities:    
Debt instruments   0.0
Series A Notes    
Liabilities:    
Debt instruments 100.0 100.0
Series A Notes | Level 1    
Liabilities:    
Debt instruments 0.0 0.0
Series A Notes | Level 2    
Liabilities:    
Debt instruments 105.7 105.3
Series A Notes | Level 3    
Liabilities:    
Debt instruments $ 0.0 $ 0.0