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Derivative Instruments and Hedging Activities - Additional Information (Details) - USD ($)
$ in Millions
1 Months Ended 3 Months Ended 12 Months Ended
Nov. 30, 2019
Dec. 31, 2019
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2008
Derivative [Line Items]              
Amortization of net (loss) gain on treasury lock     $ (18.2) $ (5.3)      
3.90% Senior Notes, due June 2022              
Derivative [Line Items]              
Stated interest rate   3.90% 3.90%        
2008 Interest Rate Protection Agreement              
Derivative [Line Items]              
Payments for (Proceeds from) settlement of interest rate protection agreement             $ 4.4
2010 Interest Rate Protection Agreement              
Derivative [Line Items]              
Payments for (Proceeds from) settlement of interest rate protection agreement           $ (9.9)  
2011 Interest Rate Protection Agreement              
Derivative [Line Items]              
Payments for (Proceeds from) settlement of interest rate protection agreement         $ 65.5    
Treasury Lock              
Derivative [Line Items]              
Amortization of net (loss) gain on treasury lock $ (13.1) $ (13.1)          
Amortization of treasury lock settlements, after tax   6.5          
Income tax benefit from stranded tax effects in accumulated OCI related to write-off of remaining treasury lock   $ 3.2