Leases (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Finite-Lived Intangible Assets [Line Items]
Weighted average remaining lease term	6 years		6 years
Operating lease, weighted average discount rate	2.60%		2.60%
Operating lease related expenses	$ 1.4	$ 1.7	$ 4.7	$ 4.9
Operating lease payments			4.3	4.5
Noncash additions to operating lease assets			$ 1.0	$ 33.9