Leases Leases - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2018	Dec. 31, 2019
Leases [Abstract]
Lease liability - operating	$ 59.1		$ 54.2
Noncancellable operating leases terminate date	2030
Right-of-use asset, operating lease	$ 55.1		$ 50.0
Weighted average remaining lease term (in years)	7 years 3 months 18 days		6 years 2 months 12 days
Weighted average discount rate (as a percentage)	5.70%		5.40%
Operating leases, rent expense		$ 18.3