Property, Plant and Equipment, Net (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		5 Months Ended	6 Months Ended
	Feb. 02, 2021	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2021	Jun. 30, 2022
Property, Plant and Equipment [Line Items]
Depreciation and depletion expense		$ 20.4			$ 51.6
Depreciation and depletion related to assets held for sale	$ 7.8		$ 57.6	$ 96.5
Cost and Timing of Decommissioning		53.0			53.0
Capitalized Costs Asset		38.2			38.2
Gain recognized from changes in cost and timing					17.4
Amount of notes receivable		$ 2.6			$ 2.6