Derivatives - Cumulative Basis Adjustment for Fair Value Hedges (Details) - Fair value hedges - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Derivatives
Hedged Liability, Fair Value Hedge	$ 598	$ 1,274
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	11	22
Short-term borrowings and current portion of long-term debt
Derivatives
Hedged Liability, Fair Value Hedge	373	499
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	5
Long-term debt
Derivatives
Hedged Liability, Fair Value Hedge	225	775
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	$ 6	$ 22

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- Definition

Amount of liability hedged in fair value hedging relationship.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109999712-113959

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- Definition

Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109999712-113959

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