Borrowings - Interest on Debt (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Interest on Debt
Interest capitalized	$ 6	$ 5
Total interest paid and accrued	1,323	1,478
Cost of financing
Interest on Debt
Interest paid	346	483
Interest expense
Interest on Debt
Interest paid	$ 971	$ 990

Amount of interest capitalized during the period.

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-Publisher FASB
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Total interest costs incurred during the period and either capitalized or charged against earnings.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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-Section 50
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