Leases (Narrative) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
	Jan. 01, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Lessee, Lease, Description [Line Items]
Right-of-use asset recognized as non-cash asset addition	$ 8.7			$ 1.5	$ 0.8
Cash paid for amounts included in measurement of operating lease liability				2.1	1.8
Total operating lease expense		$ 2.1	$ 2.0	4.1	4.3
Operating lease expense		0.9	0.9	1.9	1.8
Operating lease revenues		$ 3.0	$ 3.5	$ 6.3	$ 6.8
Minimum
Lessee, Lease, Description [Line Items]
Operating leases remaining term, lessee		1 year		1 year
Operating leases remaining term, lessor		2 years		2 years
Maximum
Lessee, Lease, Description [Line Items]
Operating leases remaining term, lessee		11 years		11 years
Operating leases remaining term, lessor		10 years		10 years