Financing Agreement - Summary of Activity Under Credit Arrangements, Excluding Acquired Borrowings (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Debt Disclosure [Abstract]
Total borrowings as of December 31	$ 1,858.2	$ 1,990.9	$ 1,726.0
Average outstanding borrowings during year	2,159.3	2,074.9	1,500.4
Maximum outstanding borrowings during year	$ 2,386.6	$ 2,300.0	$ 1,903.0
Weighted-average interest rate as of December 31	5.67%	5.33%	1.77%