Leases (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Lessee, Lease, Description [Line Items]
Right-of-use asset recognized as non-cash asset addition	$ 0.5	$ 0.9
Cash paid for amounts included in measurement of operating lease liability	0.9	1.0
Total operating lease expense	3.6	2.0
Operating lease expense	1.0	1.0
Operating lease revenues	$ 3.1	$ 3.3
Minimum
Lessee, Lease, Description [Line Items]
Operating leases remaining term, lessee	1 year
Operating leases remaining term, lessor	2 years
Maximum
Lessee, Lease, Description [Line Items]
Operating leases remaining term, lessee	11 years
Operating leases remaining term, lessor	10 years