Retirement Benefits (Fair Value Of Plan Assets Utilizing Fair Value Hierarchy) (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 4,182	$ 4,272	$ 4,027
Pension Benefits | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	540	718
Pension Benefits | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,542	1,529
Pension Benefits | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,247	2,256
Pension Benefits | Includes Medical Benefit Component Under Section401 H And Excludes Receivables Related To Pending Security Sales [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,329	4,503
Pension Benefits | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	75	90
Pension Benefits | Cash and cash equivalents | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | Cash and cash equivalents | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | Cash and cash equivalents | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	75	90
Pension Benefits | U.S. large-capitalization
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	689	663
Pension Benefits | U.S. large-capitalization | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | U.S. large-capitalization | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | U.S. large-capitalization | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	689	663
Pension Benefits | U.S. small- and mid-capitalization
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	375	353
Pension Benefits | U.S. small- and mid-capitalization | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	375	353
Pension Benefits | U.S. small- and mid-capitalization | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | U.S. small- and mid-capitalization | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | International
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	408	545
Pension Benefits | International | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	182	316
Pension Benefits | International | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | International | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	226	229
Pension Benefits | Global
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	680	721
Pension Benefits | Global | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | Global | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | Global | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	680	721
Pension Benefits | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	463	479
Pension Benefits | Corporate bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | Corporate bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	463	479
Pension Benefits | Corporate bonds | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | Municipal bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	36	43
Pension Benefits | Municipal bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | Municipal bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	36	43
Pension Benefits | Municipal bonds | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | U.S. Treasury and agency securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,032	994
Pension Benefits | U.S. Treasury and agency securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | U.S. Treasury and agency securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,032	994
Pension Benefits | U.S. Treasury and agency securities | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | Diversified Credit
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	344
Pension Benefits | Diversified Credit | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | Diversified Credit | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | Diversified Credit | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	344	305
Pension Benefits | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	(6)	62
Pension Benefits | Other | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	(17)	49
Pension Benefits | Other | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	11	13
Pension Benefits | Other | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | Real estate
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	233	248
Pension Benefits | Real estate | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | Real estate | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Pension Benefits | Real estate | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	233	248
Pension Benefits | Medical benefit assets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	(200)	(196)
Pension Benefits | Net receivables
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	53	(35)
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,493	1,393	$ 1,249
Postretirement Benefits | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	517	459
Postretirement Benefits | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	173	161
Postretirement Benefits | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	601	575
Postretirement Benefits | Includes Medical Benefit Component Under Section401 H And Excludes Receivables Related To Pending Security Sales [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,291	1,195
Postretirement Benefits | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	25	10
Postretirement Benefits | Cash and cash equivalents | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	25	10
Postretirement Benefits | Cash and cash equivalents | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefits | Cash and cash equivalents | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefits | U.S. large-capitalization
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	423	383
Postretirement Benefits | U.S. large-capitalization | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	332	302
Postretirement Benefits | U.S. large-capitalization | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefits | U.S. large-capitalization | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	91	81
Postretirement Benefits | U.S. small- and mid-capitalization
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	106	96
Postretirement Benefits | U.S. small- and mid-capitalization | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	106	96
Postretirement Benefits | U.S. small- and mid-capitalization | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefits | U.S. small- and mid-capitalization | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefits | International
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	106	100
Postretirement Benefits | International | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	54	51
Postretirement Benefits | International | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefits | International | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	52	49
Postretirement Benefits | Global
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	165	174
Postretirement Benefits | Global | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefits | Global | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefits | Global | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	165	174
Postretirement Benefits | Municipal bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	173	161
Postretirement Benefits | Municipal bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefits | Municipal bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	173	161
Postretirement Benefits | Municipal bonds | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefits | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	293	271
Postretirement Benefits | Other | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefits | Other | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Postretirement Benefits | Other | NAV
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	293	271
Postretirement Benefits | Medical benefit assets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	200	196
Postretirement Benefits | Net receivables
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 2	$ 2