Leases (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Lessee, Lease, Description [Line Items]
Lease payments, leases not yet commenced	$ 33.4	$ 34.7
Maximum
Lessee, Lease, Description [Line Items]
Remaining lease term	33 years