Financial Instruments and Derivatives (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Jun. 30, 2020
Financial Instruments And Derivatives [Abstract]
Initial Margin Collateral Receivable	$ 462	$ 462
Net investment hedge, European business		5,300
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	10,000	10,000	$ 7,500
Terminated short-term committed line of credit	7,000
Short Term Financing [Member]
Debt Instrument [Line Items]
Unused credit line	11,000	11,000
Long Term Financing [Member]
Debt Instrument [Line Items]
Unused credit line	$ 200	$ 200