Financial Instruments - Cash Flow Hedges After-tax Gains/(Losses) (Details) - Cash flow hedges - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
After-tax gains/(losses) recognized in other comprehensive earnings/(losses)	$ (21)	$ (69)
Interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
After-tax gains/(losses) reclassified from accumulated other comprehensive income into earnings/(losses)	(81)	0
After-tax gains/(losses) recognized in other comprehensive earnings/(losses)	$ (21)	$ (69)

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.

No definition available.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
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-Section 55
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Amount, after tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e689-108580

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e637-108580

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