Fresh Start Accounting Reorganization Value (Details) - USD ($) $ in Millions	Sep. 30, 2019	Jul. 01, 2019
Fresh-Start Adjustment [Line Items]
Enterprise Value	$ 3,100	$ 3,100
Cash and Cash Equivalents		125
Postconfirmation, Non-debt and non-pension current liabilities		540
Postconfirmation, Non-debt and non-pension long-term liabilities		527
Postconfirmation, Total non-debt and non-pension liabilities		1,067
Total liabilities and equity (deficit)		$ 4,292
Minimum [Member]
Fresh-Start Adjustment [Line Items]
Reorganization Value	2,900
Maximum [Member]
Fresh-Start Adjustment [Line Items]
Reorganization Value	$ 3,300

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Current liabilities after fresh-start adjustments less debt obligations and pension liabilities

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Long-term liabilities after fresh-start adjustments less debt obligations and pension liabilities

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Total liabilities after fresh-start adjustments less debt obligations and pension liabilities

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

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Total liabilities and stockholders' equity 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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