Debt instrument redemption amount.

No definition available.

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- Definition

Extinguishment Of Debt, Early Termination Premium

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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Period Type:	instant

- Definition

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

+ 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 210.5-02.22(a)(1))
-URI http://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, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28555-108399

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Period Type:	instant

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6036836-161870

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-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
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Debt - Public Debt (Details) - USD ($)					3 Months Ended		9 Months Ended	12 Months Ended
Debt - Public Debt (Details) - USD ($)	Jan. 15, 2021	May 21, 2020	Apr. 06, 2020	Oct. 15, 2019	Mar. 31, 2021	Jun. 30, 2020	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Apr. 24, 2020	Mar. 31, 2018
Debt Instrument [Line Items]
Early termination premium						$ 35,000,000
Interest expense							$ 17,000,000			$ 19,000,000
Debt prepayment cost								$ 59,000,000	$ 0	$ 17,000,000
5.400% Notes, due 2021
Debt Instrument [Line Items]
Early redemption of debt		$ 589,000,000	$ 300,000,000
Long- term debt, interest rate (percentage)		5.40%	5.40%					5.40%
Interest expense						24,000,000
Debt prepayment cost			$ 315,000,000
5.400% Notes, due 2021 \| Subsequent Event
Debt Instrument [Line Items]
Early redemption of debt	$ 361,000,000
Long- term debt, interest rate (percentage)	5.40%
Interest expense	$ 19,000,000
5.400% Notes, due 2021 \| Scenario, forecast
Debt Instrument [Line Items]
Early termination premium					$ 5,000,000
5.870% Notes, due 2022
Debt Instrument [Line Items]
Early redemption of debt		$ 151,000,000
Long- term debt, interest rate (percentage)		5.87%						5.87%
Interest expense							$ 4,000,000
6.875% Notes, due 2025
Debt Instrument [Line Items]
Long- term debt, interest rate (percentage)								6.875%			6.875%
Aggregate principal amount											$ 1,200,000,000
Deferred financing costs						$ 14,000,000
6.150% Notes, due 2020
Debt Instrument [Line Items]
Early redemption of debt			$ 1,000,000,000
Long- term debt, interest rate (percentage)			6.15%					6.15%
Debt prepayment cost			$ 1,020,000,000
1.63% convertible notes
Debt Instrument [Line Items]
Early redemption of debt				$ 403,000,000
Long- term debt, interest rate (percentage)				1.63%
5.72% Notes due 2019
Debt Instrument [Line Items]
Long- term debt, interest rate (percentage)												5.72%
Aggregate principal amount												$ 500,000,000
Debt instrument redemption amount												$ 518,000,000