Long-Term Debt (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Principal outstanding	$ 9,709	$ 8,963
Revolving Facility [Member]
Debt Instrument [Line Items]
Letters of credit outstanding	236
Available borrowing capacity	$ 664
Line of Credit Facility, Maximum Permitted Leverage Ratio - Initial Covenant Term	3.50%
Line of Credit Facility, Maximum Permitted Leverage Ratio - 2nd Covenant Term	3.25%
Line of Credit Facility, Maximum Permitted Leverage Ratio - 3rd Covenant Term	3.00%
Line of credit facility maximum borrowing capacity	$ 900
Revolving Facility [Member] \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member]
Debt Instrument [Line Items]
Interest rate margin	3.50%
Revolving Facility [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Interest rate margin	2.50%
Revolving Facility [Member] \| SOFR Floor [Member]
Debt Instrument [Line Items]
Interest rate margin	0.00%
Revolving Facility - After April 30, 2025 [Member]
Debt Instrument [Line Items]
Line of credit facility maximum borrowing capacity	$ 850
Secured Debt [Member]
Debt Instrument [Line Items]
Principal outstanding	8,859	8,113
Secured Debt [Member] \| First Lien Notes Due 10/15/2027 [Member]
Debt Instrument [Line Items]
Principal outstanding	$ 1,150	$ 1,150
Interest rate	5.875%	5.875%
Secured Debt [Member] \| First Lien Notes Due 5/1/2028 [Member]
Debt Instrument [Line Items]
Principal outstanding	$ 1,550	$ 1,550
Interest rate	5.00%	5.00%
Secured Debt [Member] \| First Lien Notes Due 3/15/2031 [Member]
Debt Instrument [Line Items]
Principal outstanding	$ 750
Interest rate	8.625%
Secured Debt [Member] \| First Lien Notes Due 5/15/2030 [Member]
Debt Instrument [Line Items]
Principal outstanding	$ 1,200	$ 1,200
Interest rate	8.75%	8.75%

Debtor-in-Possession Financing, Line of Credit Facility, Remaining Borrowing Capacity

No definition available.

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- Definition

The maximum permitted leverage ratio under the credit agreement during the 2nd Covenant Term.

+ References

No definition available.

+ Details

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- Definition

The maximum permitted leverage ratio under the credit agreement during the 3rd Covenant Term.

+ References

No definition available.

+ Details

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- Definition

The maximum permitted leverage ratio under the credit agreement during the covenant's intial term period.

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI https://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870

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-Topic 944
-SubTopic 210
-Section S99
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-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

+ Details

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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
-Paragraph 1B
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 45
-Paragraph 18
-URI https://asc.fasb.org/extlink&oid=124437977&loc=SL2890576-112764

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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