Lessee Arrangements - Lease Expense (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Leases [Abstract]
Operating lease expense	$ 2.9	$ 9.3
Variable lease expense	1.0	3.5
Short-term lease expense	0.7	1.6
Total lease expense	$ 4.6	$ 14.4