Leases - Lease Expense (Details) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)
Leases [Abstract]
Operating lease cost included in continuing operations	$ 3.0	$ 5.7
Operating leases, weighted average remaining lease term (years)	8 years 6 months	8 years 6 months
Operating leases, weighted average discount rate (percent)	5.70%	5.70%