Debt - Additional Information (Details)		1 Months Ended	12 Months Ended
	Apr. 25, 2018 USD ($)	May 31, 2019 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Debt, gross			$ 847,500,000
Commercial paper			0	$ 117,800,000
Total debt			839,600,000	1,029,100,000
Other Credit Facilities
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity			21,400,000
Line of credit facility, amount outstanding			0
Line of Credit | Revolving credit facilities
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity	$ 800,000,000.0	$ 900,000,000.0
Debt term	5 years
Line of Credit Facility, Increase (Decrease), Net		$ 100,000,000.0
Debt, gross			36,100,000	35,800,000
Remaining borrowing capacity			863,900,000
Line of Credit | Revolving credit facilities | Minimum
Debt Instrument [Line Items]
Covenant, unrestricted cash			$ 5,000,000.0
Leverage ratio covenant			3.75
EBITDA ratio covenant			1.00
Line of Credit | Revolving credit facilities | Maximum
Debt Instrument [Line Items]
Covenant, unrestricted cash			$ 250,000,000.0
Leverage ratio covenant			1.00
EBITDA ratio covenant			3.00
Term loans | Term Loans, 1.224% due in 2023
Debt Instrument [Line Items]
Debt, gross			$ 200,000,000.0	200,000,000.0
Line of credit increase limit			300,000,000.0
Senior Notes | Senior Notes, 4.500% due in 2029
Debt Instrument [Line Items]
Debt, gross			400,000,000.0	$ 400,000,000.0
Senior Notes | Senior Notes Maturing In 2021
Debt Instrument [Line Items]
Total debt			$ 103,800,000