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Debt - Long Term Debt (Details) - USD ($) $ in Millions	Mar. 16, 2021	Jun. 30, 2021	Dec. 31, 2020	Sep. 22, 2020	Jul. 05, 2019	Jun. 04, 2019	Jul. 02, 2018
Debt Instrument [Line Items]
Long-term Debt		$ 1,122.3	$ 1,172.8
2.400% Senior Notes due September 30, 2030
Debt Instrument [Line Items]
Long-term Debt		395.8
Secured Debt
Debt Instrument [Line Items]
Repayments of Long-term Debt	$ 50.0
Secured Debt \| Term Loan due July 5, 2023
Debt Instrument [Line Items]
Long-term Debt		0.0	49.9		$ 49.9
Line of credit facility, maximum borrowing capacity						$ 50.0
Senior Notes
Debt Instrument [Line Items]
Long-term Debt			448.8
Senior Notes \| 5.000% Senior Notes due September 19, 2022
Debt Instrument [Line Items]
Long-term Debt		277.6	278.3
Stated interest rate							5.00%
Senior Notes \| 4.350% Senior Notes due February 15, 2025
Debt Instrument [Line Items]
Long-term Debt		$ 448.8
Stated interest rate		4.35%
Senior Notes \| 2.400% Senior Notes due September 30, 2030
Debt Instrument [Line Items]
Long-term Debt		$ 395.9	$ 395.8
Stated interest rate				2.40%