Summary of Short-Term Borrowings and Long-Term Debt (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Short-term borrowings
Commercial paper issuances	$ 349,000,000.0	$ 248,600,000
Various debt due to international banks	2,400,000	4,300,000
Total short-term borrowings	351,400,000	252,900,000
Long-term debt
Debt issuance costs, net	(9,400,000)	(11,500,000)
Net long-term debt	1,812,500,000	1,810,200,000
2.45% Senior notes due August 1, 2022
Long-term debt
Senior notes	300,000,000.0	300,000,000.0
Less: Discount	(100,000)	(200,000)
2.875% Senior notes due October 1, 2022
Long-term debt
Senior notes	400,000,000.0	400,000,000.0
Less: Discount	(100,000)	(100,000)
Term Loan
Long-term debt
Term loan	300,000,000.0	300,000,000.0
3.15% Senior notes due August 1, 2027
Long-term debt
Senior notes	425,000,000.0	425,000,000.0
Less: Discount	(300,000)	(300,000)
3.95% Senior notes due August 1, 2047
Long-term debt
Senior notes	400,000,000.0	400,000,000.0
Less: Discount	$ (2,600,000)	$ (2,700,000)