v3.20.1

Debt - Additional Information (Details) - USD ($) $ in Millions		1 Months Ended	12 Months Ended
	Nov. 25, 2019	Jan. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Oct. 18, 2019	Sep. 03, 2019	Aug. 15, 2019
Debt Instrument [Line Items]
Gain (loss) on extinguishment of debt			$ 10	$ 73
Debtor-in possession financing, loans outstanding			148	0
Senior Secured Note due May 1, 2024
Debt Instrument [Line Items]
Principal amount issued		$ 1,100
Gain (loss) on extinguishment/modification of debt		(12)
Gain (loss) on extinguishment of debt		$ 53
Unsecured Debt
Debt Instrument [Line Items]
Gain (loss) on extinguishment of debt			10	32
Repayments of outstanding amount			40	49
Aggregate principal amount repurchased			50	84
Senior Secured Notes due February 15, 2025
Debt Instrument [Line Items]
Principal amount issued					$ 138
Cash interest payment due, not paid							$ 40
Senior Unsecured Notes due September 1, 2022
Debt Instrument [Line Items]
Cash interest payment due, not paid						$ 7
Debtor-In-Possession Senior Secured Superpriority Revolving Credit Facility
Debt Instrument [Line Items]
Principal amount issued	$ 629
Debtor-in-possession financing, amount arranged	315
Debtor-in possession financing, remaining borrowing capacity			150
Debtor-in possession financing, loans outstanding			148	$ 0
Letter of Credit
Debt Instrument [Line Items]
Debtor-in-possession financing, amount arranged	$ 50
Debtor-in-possession letter of credit outstanding			$ 17
LIBOR \| Debtor-In-Possession Senior Secured Superpriority Revolving Credit Facility
Debt Instrument [Line Items]
Debtor-in possession financing, basis spread on variable rate	3.50%
Debt Instrument Variable Rate Alternate Base Rate \| Debtor-In-Possession Senior Secured Superpriority Revolving Credit Facility
Debt Instrument [Line Items]
Debtor-in possession financing, basis spread on variable rate	2.50%
Debtor-in possession financing, unused capacity, commitment fee percentage	0.50%

Debtor-In Possession Financing, Basis Spread On Variable Rate

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- Definition

Debtor-In Possession Financing, Remaining Borrowing Capacity

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Debtor-In Possession Financing, Unused Capacity, Commitment Fee Percentage

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- Definition

Face (par) amount of debt instrument at time of issuance.

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-Publisher FASB
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-SubTopic 30
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- Definition

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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Face (par) amount of the original debt instrument that was repurchased.

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- Definition

Amount debtor-in-possession financing arranged (but not necessarily all borrowed).

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No definition available.

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Amount of debtor-in-possession borrowings outstanding.

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Amount of letters of credit outstanding under debtor-in-possession financing arrangement.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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For a debtor, the aggregate gain (loss) recognized on the restructuring of payables arises from the difference between the book value of the debt before the restructuring and the fair value of the payments on the debt after restructuring is complete.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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