Derivatives and Hedging Activities Textuals (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Derivatives, hedged liabilities	$ 8,700	$ 13,500
Cumulative amount of fair value hedging adjustments	(2)	(184)
Net increases (reductions) in interest expense on long-term debt	90	75	$ (53)
Notional amounts of foreign currency derivatives	3,000	2,900
Gain (loss) on net investment hedges	(44)	127	(174)
Net gains on derivatives not designated as hedges	87	59	$ 21
Credit Risk Contract [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative in net liability position	38
Fair Value Hedging [Member]
Derivatives, Fair Value [Line Items]
Derivatives, hedged liabilities	$ 8,800	$ 13,800

Changes in the fair value of the derivatives and the related underlying foreign currency exposure

No definition available.

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- Definition

Represents the amount of a net (increase) reduction to interest expense, primarily related to the net settlements on the Company's fair value hedges.

+ References

No definition available.

+ Details

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- Definition

Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

+ References

No definition available.

+ Details

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- Definition

Nominal or face amount used to calculate payments on the derivative liability.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624258-113959

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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 addition (reduction) to the amount at which a liability could be incurred (settled) in a current transaction between willing parties.

+ References

No definition available.

+ Details

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- Definition

Amount of increase (decrease) in the cumulative translation adjustment from gain (loss), after tax, on foreign currency derivatives, that are designated as, and are effective as, economic hedges of a net investment in a foreign entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section 45
-Paragraph 20
-Subparagraph (b),(c),(d)
-URI http://asc.fasb.org/extlink&oid=118261656&loc=d3e32211-110900

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- Details

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