Fresh Start Accounting (Reconciliation Of Enterprise Value To Reorganization Value ) (Details) - Successor [Member] $ in Millions	Jun. 30, 2020 USD ($)
Fresh-Start Adjustment [Line Items]
Enterprise value	$ 12,500
Plus: Cash and cash equivalents and restricted cash	940
Plus: Current liabilities (excluding debt, finance leases, and non-operating liabilities)	1,179
Plus: Long term liabilities (excluding debt, finance leases, deferred tax liability)	307
Reorganization value	$ 14,926

Postconfirmation Current Liabilities Excluding Debt, Finance Leases, And Non Operating Liabilities

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- Definition

Postconfirmation Noncurrent Liabilities Excluding Debt, Finance Leases, And Deferred Tax Liability

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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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Amount of current restricted cash and cash equivalents at the balance sheet date after fresh-start adjustments.

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Amount attributed to the reconstituted entity, as well as the expected net realizable value of those assets that will be disposed before reconstitution occurs.

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Amount of reorganization value related to present value of discounted cash flows of the emerging entity. Reorganization value is the amount attributed to the reconstituted entity, as well as the expected net realizable value of those assets that will be disposed before reconstitution occurs.

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