Chapter 11 Proceedings and Ability to continue as a Going Concern - Debtor in Possession Credit Agreement (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended	11 Months Ended	12 Months Ended
Dec. 31, 2019	Jun. 30, 2019	Dec. 13, 2019	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Prepetition charges	$ 0	$ 86	$ 86	$ 0	$ 0

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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