Employee Benefits (Schedule Of Fair Value Of Pension Plan Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
United States [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 563	$ 526
United States [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	264	247
United States [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	299	279
Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	21	19
Foreign Plan [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6	6
Foreign Plan [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	15	13
Pension Plan [Member] | United States [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	563	526	$ 486
Pension Plan [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	21	19	$ 17
Cash and Cash Equivalents [Member] | United States [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Cash and Cash Equivalents [Member] | United States [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Cash and Cash Equivalents [Member] | United States [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Cash and Cash Equivalents [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6	6
Cash and Cash Equivalents [Member] | Foreign Plan [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6	6
Cash and Cash Equivalents [Member] | Foreign Plan [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Common Stock | United States [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	15
Common Stock | United States [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	15
Common Stock | United States [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Common Stock | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Common Stock | Foreign Plan [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Common Stock | Foreign Plan [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Large-Cap Mutual Funds [Member] | United States [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	196	161
Large-Cap Mutual Funds [Member] | United States [Member] | Level 1 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	64	49
Large-Cap Mutual Funds [Member] | United States [Member] | Level 2 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	132	112
Large-Cap Mutual Funds [Member] | Foreign Plan [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2	1
Large-Cap Mutual Funds [Member] | Foreign Plan [Member] | Level 1 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Large-Cap Mutual Funds [Member] | Foreign Plan [Member] | Level 2 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2	1
Small-Cap Mutual Funds [Member] | United States [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14	22
Small-Cap Mutual Funds [Member] | United States [Member] | Level 1 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	8
Small-Cap Mutual Funds [Member] | United States [Member] | Level 2 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14	14
Small-Cap Mutual Funds [Member] | Foreign Plan [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Small-Cap Mutual Funds [Member] | Foreign Plan [Member] | Level 1 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Small-Cap Mutual Funds [Member] | Foreign Plan [Member] | Level 2 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International Mutual Funds [Member] | United States [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	134	120
International Mutual Funds [Member] | United States [Member] | Level 1 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	84	75
International Mutual Funds [Member] | United States [Member] | Level 2 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	50	45
International Mutual Funds [Member] | Foreign Plan [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6	5
International Mutual Funds [Member] | Foreign Plan [Member] | Level 1 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
International Mutual Funds [Member] | Foreign Plan [Member] | Level 2 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6	5
Bond Mutual Funds [Member] | United States [Member] | Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	212	198
Bond Mutual Funds [Member] | United States [Member] | Level 1 [Member] | Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	116	100
Bond Mutual Funds [Member] | United States [Member] | Level 2 [Member] | Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	96	98
Bond Mutual Funds [Member] | Foreign Plan [Member] | Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7	7
Bond Mutual Funds [Member] | Foreign Plan [Member] | Level 1 [Member] | Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Bond Mutual Funds [Member] | Foreign Plan [Member] | Level 2 [Member] | Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7	7
Short Term Investment Funds [Member] | United States [Member] | Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7	10
Short Term Investment Funds [Member] | United States [Member] | Level 1 [Member] | Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Short Term Investment Funds [Member] | United States [Member] | Level 2 [Member] | Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7	10
Short Term Investment Funds [Member] | Foreign Plan [Member] | Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Short Term Investment Funds [Member] | Foreign Plan [Member] | Level 1 [Member] | Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Short Term Investment Funds [Member] | Foreign Plan [Member] | Level 2 [Member] | Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0