Debt (Schedule Of Changes In Debt) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($)
Debt Instrument [Line Items]
Balance as of beginning-of-year	$ 6,367
Notes issued	499
Repayment of notes	(300)
Unamortized adjustments from discontinued hedges	263
Fair value hedge on interest rate swap agreement	(82)
Balance as of end-of-period	6,748
LIBOR + 150 bps Term Loan Issued, Due 2022 [Member]
Debt Instrument [Line Items]
Notes issued	$ 500
LIBOR + 150 bps Term Loan Issued, Due 2022 [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable rate	1.50%
6.25% Senior Notes, Due 2020 [Member]
Debt Instrument [Line Items]
Repayment of notes	$ (300)
Interest rate	6.25%