Related Party Transactions (Management) (Narrative) (Details) - Management [Member] - Equipment, Supplies and Services [Member] - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Related Party Transaction [Line Items]
Payments, related party	$ 16.2	$ 17.8	$ 41.5	$ 46.3
Payables, related party	7.6		7.6		$ 14.7
Revenue, related party	1.3	$ 0.6	2.3	$ 0.9
Receivables, net, related party	$ 0.4		$ 0.4

Amount for accounts payable to related parties.

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