Indebtedness (Details) - USD ($) $ in Millions	1 Months Ended		3 Months Ended		9 Months Ended
	Jul. 31, 2022	Feb. 28, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 15, 2022	Sep. 15, 2015
Debt Instrument [Line Items]
Face amount								$ 1,000.0
Redemption rate							99.92%
Senior notes interest rate			3.625%		3.625%
Extinguishment of Debt, Amount	$ 2.4
Repayments of Senior Debt		$ 151.8
Interest Expense			$ 59.9	$ 66.3	$ 191.8	$ 187.3
5.200% Senior Notes due 2045
Debt Instrument [Line Items]
Senior notes interest rate			5.20%		5.20%
Repayments of Senior Debt		12.1
Debt Instrument, Redemption, Amount		8.9
Long Term Debt, Exchanged, Amount		624.6
Gain (Loss) on Extinguishment of Debt			$ 3.2
Repayments of borrowings and premiums paid on debt exchange			13.8
Interest Expense			$ 6.1
3.250% Senior Notes, Due February 15, 2051
Debt Instrument [Line Items]
Senior notes interest rate			3.25%		3.25%
Long Term Debt, Exchanged, Amount		$ 700.7