Related Party Transactions (Management and Other Transactions) (Narrative) (Details) - Management [Member] - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Oil And Gas 2017 Acquisition [Member]
Related Party Transaction [Line Items]
Business combinations, cash paid			$ 40.6
Contingent consideration, earn-out liability		$ 75.5
Equipment, Supplies And Services [Member]
Related Party Transaction [Line Items]
Payments, related party	$ 108.0	134.4	110.7
Payables, related party	14.7	17.3
Revenue, related party	$ 2.3	10.3	$ 2.6
Receivables, related party		$ 0.3

Amount for accounts payable to related parties.

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