Fresh Start Accounting (Fresh Start - Cumulative Impact Of Reorganization) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Apr. 30, 2021
Successor [Member]
Net impact on accumulated deficit	$ 414
Reorganization Adjustments [Member]
Net impact on accumulated deficit		10,028
Reorganization Adjustments [Member] \| Successor [Member]
Gain on settlement of Liabilities Subject to Compromise		5,274
Cancellation of Predecessor equity		4,754
Net impact on accumulated deficit		$ 10,028

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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