Fresh Start Accounting Reorganization Adjustments - Sources and Uses of Cash (Details) $ in Millions	Jul. 01, 2019 USD ($)
Fresh-Start Adjustment [Line Items]
Proceeds from the Rights Offerings	$ 300
Proceeds from the Senior Notes	450
Proceeds from the Senior Secured Term Loan	1,196
Release of utility deposit	1
Total sources	1,947
Repayment of 1st Lien Notes	(1,383)
Repayment of DIP Term Loan Facility	(350)
Repayment of DIP Term Loan interest	(5)
Debt and Equity Backstop premiums	(104)
Financing fees	(19)
Success fees at emergence	(31)
Other professional fees	(26)
Total uses	(1,918)
Cash and Cash Equivalents	$ 29