Long-Term Debt - 2021 8 Percent Senior Secured Notes (Details) - 2021 Senior Unsecured Notes - Senior Notes $ in Millions	1 Months Ended
Jan. 31, 2021 USD ($)
Debt Instrument [Line Items]
Proceeds from issuance of senior secured notes	$ 1,175
Note stated interest rate	8.00%
Prior to February 1, 2023
Debt Instrument [Line Items]
Redemption price (as a percent)	100.00%
Redemption period	12 months
Initial twelve-month period, prior to February 1, 2023
Debt Instrument [Line Items]
Redemption price (as a percent)	103.00%
Initial twelve-month period, prior to February 1, 2023 \| Maximum
Debt Instrument [Line Items]
Redemption period	12 months
Percent amount the can be redeemed	10.00%
Subsequent the initial twelve-month period, prior to February 1, 2023
Debt Instrument [Line Items]
Redemption period	12 months
Subsequent the initial twelve-month period, prior to February 1, 2023 \| Maximum
Debt Instrument [Line Items]
Redemption period	12 months
Percent amount the can be redeemed	10.00%

Debt Instrument, Redemption Price, Period

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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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.

+ References

No definition available.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
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-URI https://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823

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Percentage of principal amount of debt redeemed.

+ References

No definition available.

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- Definition

The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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