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

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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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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- Definition

Fair value amount of debt instrument that was repurchased.

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- 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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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Debt 2019 Debt Redemption (Details) - USD ($) $ in Millions		1 Months Ended	3 Months Ended	12 Months Ended
Debt 2019 Debt Redemption (Details) - USD ($) $ in Millions	Dec. 31, 2020	Aug. 31, 2019	Sep. 28, 2019	Jan. 02, 2021	Dec. 28, 2019	May 31, 2020	May 31, 2018	Nov. 30, 2016	Mar. 31, 2014	May 31, 2012	Dec. 31, 2010
Debt Instrument [Line Items]
Interest expense	$ 20		$ 16	$ 281	$ 284
Debt repurchase amount			$ 1,000
4.15% U.S. Dollar Notes Due 2019
Debt Instrument [Line Items]
Debt instrument, stated interest rate			4.15%
Debt repurchase amount			$ 500
4.0% U.S. Dollar Notes Due 2020
Debt Instrument [Line Items]
Debt instrument, stated interest rate			4.00%			4.00%					4.00%
Interest expense		$ 6
Debt repurchase amount		248	$ 248						$ 150
3.25% U.S. Dollar Notes Due 2021
Debt Instrument [Line Items]
Debt instrument, stated interest rate	3.25%		3.25%				3.25%
Interest expense		6		3
Debt repurchase amount	$ 198	202	$ 202	198
2.65% U.S. Dollar Notes Due 2023
Debt Instrument [Line Items]
Debt instrument, stated interest rate			2.65%					2.65%
Interest expense		2
Debt repurchase amount		$ 50	$ 50
3.125% U.S. Dollar Debentures Due 2022
Debt Instrument [Line Items]
Debt instrument, stated interest rate	3.125%									3.125%
Interest expense				17
Debt repurchase amount	$ 358			$ 358					$ 342