Commitments and Contingencies, Consolidated Lease Expense (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Consolidated Lease Expense [Abstract]
Fixed lease expense	$ 13.1		$ 26.5
Variable lease expense	1.1		2.9
Subtotal operating lease expense	14.2		29.4
Short-term lease expense	11.7		23.5
Total operating lease expense	$ 25.9	$ 25.8	$ 52.9	$ 51.4