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Goodwill and Intangible Assets Narrative (Details) - USD ($) $ in Millions	1 Months Ended	11 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 13, 2019	Dec. 31, 2020	Dec. 31, 2018	Dec. 12, 2019
Goodwill [Line Items]
Goodwill, Period Increase (Decrease)	$ 239
Goodwill, Impaired, Accumulated Impairment Loss					$ 3,400
Goodwill Impairment	0	$ 730	$ 239	$ 1,917
Eastern Hemisphere [Member]
Goodwill [Line Items]
Goodwill, Period Increase (Decrease)			239
Goodwill Impairment		222	239	537
Western Hemisphere [Member]
Goodwill [Line Items]
Goodwill, Period Increase (Decrease)	$ 0
Goodwill Impairment		$ 508	$ 0	$ 1,400