Property and Equipment Property and Equipment (Sale of Produced Water Assets) (Details) - KFM - Affiliated Entity $ in Millions		2 Months Ended
Nov. 09, 2018 USD ($) well	Dec. 31, 2018 USD ($)
Property, Plant and Equipment [Line Items]
Number of produced water disposal wells sold \| well	20
Proceeds from sale of business	$ 98.0
Proceeds from sale of water systems	$ 90.0
Accounts receivable, related party		$ 8.0
Initial term	15 years
Expenses recognized		$ 4.7

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