Commitments and Contingencies, Consolidated Lease Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Consolidated Lease Expense [Abstract]
Non-cash lease expense (amortization of ROU assets)	$ 42.8	$ 0.0	$ 0.0
Related accretion expense on lease liability balances	9.0
Total fixed lease expense	51.8
Variable lease expense	6.2
Subtotal operating lease expense	58.0
Short-term operating leases	48.6
Total operating lease expense	$ 106.6	$ 86.4	$ 103.6