Chapter 11 - Condensed Combined Debtors Financial Statements (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Reorganization, Chapter 11 [Line Items]
Restricted cash portion of cash collateral securing Senior Notes	$ 223	$ 168
Cash and cash equivalents	312	491
Amount due from related parties, net	28	85
Due from Related Parties, Noncurrent	0	6
Liabilities subject to compromise	6,235	$ 0
Pro Forma
Reorganization, Chapter 11 [Line Items]
Restricted cash portion of cash collateral securing Senior Notes	136
Entities Not In Bankruptcy
Reorganization, Chapter 11 [Line Items]
Net cash outflows from changes in the above assets.	4
Entities Not In Bankruptcy \| Pro Forma
Reorganization, Chapter 11 [Line Items]
Reduction to current restricted cash due to exclusion	24
Reduction to cash due to exclusion	8
Cash and cash equivalents	304
Amount due from related parties, net	21
Due from Related Parties, Noncurrent	9
Liabilities subject to compromise	$ 8

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