Derivative Financial Instruments (Location And Amounts Of Pre-Tax Gains (Losses) On Cash Flow Hedge Derivatives Financial Instruments) (Details) - Cash Flow Hedging [Member] - Designated as Hedging Instrument [Member] - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Net Gains Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (effective portion)	$ 15	$ 6	$ 50	$ (8)
Cost Of Revenues [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Gains Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (effective portion)	13	5	43	(7)
Selling, General and Administrative Expenses [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net Gains Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (effective portion)	2	1	7	(1)
Foreign Exchange Contract
Derivative Instruments, Gain (Loss) [Line Items]
Change in Derivative Gains Recognized in Accumulated Other Comprehensive Income (Loss) (effective portion)	$ 33	$ 77	$ 47	$ (1)