Benefit Plans (Fair Values of Pension and Postretirement Plan Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	$ 6,603	$ 8,793	$ 8,911
Pension [Member] | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	1,098	1,147
Pension [Member] | Municipal Bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	82	60
Pension [Member] | Debt Security, Government, Non-US [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	32	88
Pension [Member] | Corporate Debt Security, Above Investment Grade [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	2,747	3,442
Pension [Member] | Corporate Debt Security, Below Investment Grade [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	756	1,032
Pension [Member] | Common stock: International equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	327	373
Pension [Member] | Common stock: U.S. equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	591	856
Pension [Member] | Asset-Backed Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	161	89
Pension [Member] | Other, Net [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	243	200
Pension [Member] | U S Large Cap [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	$ 312	$ 873
Defined Benefit Plan, Plan Assets, Fair Value by Hierarchy and NAV [Extensible List]	NAV [Member]	NAV [Member]
Pension [Member] | U S Small Cap [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	$ 75	$ 462
Defined Benefit Plan, Plan Assets, Fair Value by Hierarchy and NAV [Extensible List]	NAV [Member]	NAV [Member]
Pension [Member] | International Developed Markets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	$ 49	$ 125
Defined Benefit Plan, Plan Assets, Fair Value by Hierarchy and NAV [Extensible List]	NAV [Member]	NAV [Member]
Pension [Member] | Other Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	$ 130	$ 46
Pension [Member] | Fair Value, Inputs, Level 1, 2 and 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	6,037	7,287
Pension [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	917	1,281
Pension [Member] | Level 1 [Member] | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	0	0
Pension [Member] | Level 1 [Member] | Municipal Bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	0	0
Pension [Member] | Level 1 [Member] | Debt Security, Government, Non-US [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	0	0
Pension [Member] | Level 1 [Member] | Corporate Debt Security, Above Investment Grade [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	0	0
Pension [Member] | Level 1 [Member] | Corporate Debt Security, Below Investment Grade [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	0	0
Pension [Member] | Level 1 [Member] | Common stock: International equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	327	373
Pension [Member] | Level 1 [Member] | Common stock: U.S. equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	591	856
Pension [Member] | Level 1 [Member] | Asset-Backed Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	0	0
Pension [Member] | Level 1 [Member] | Other, Net [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	(1)	52
Pension [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	5,120	6,006
Pension [Member] | Level 2 [Member] | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	1,098	1,147
Pension [Member] | Level 2 [Member] | Municipal Bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	82	60
Pension [Member] | Level 2 [Member] | Debt Security, Government, Non-US [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	32	88
Pension [Member] | Level 2 [Member] | Corporate Debt Security, Above Investment Grade [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	2,747	3,442
Pension [Member] | Level 2 [Member] | Corporate Debt Security, Below Investment Grade [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	756	1,032
Pension [Member] | Level 2 [Member] | Common stock: International equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	0	0
Pension [Member] | Level 2 [Member] | Common stock: U.S. equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	0	0
Pension [Member] | Level 2 [Member] | Asset-Backed Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	161	89
Pension [Member] | Level 2 [Member] | Other, Net [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	244	148
Pension [Member] | NAV [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	436	1,460
Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	122	185	$ 201
Postretirement Benefit Plan [Member] | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	5	5
Postretirement Benefit Plan [Member] | Debt Security, Government, Non-US [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	2	3
Postretirement Benefit Plan [Member] | Corporate Debt Security, Above Investment Grade [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	37	55
Postretirement Benefit Plan [Member] | Corporate Debt Security, Below Investment Grade [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	7	10
Postretirement Benefit Plan [Member] | Other, Net [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	3	0
Postretirement Benefit Plan [Member] | U S Large Cap [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	$ 47	$ 84
Defined Benefit Plan, Plan Assets, Fair Value by Hierarchy and NAV [Extensible List]	NAV [Member]	NAV [Member]
Postretirement Benefit Plan [Member] | International Developed Markets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	$ 18	$ 25
Defined Benefit Plan, Plan Assets, Fair Value by Hierarchy and NAV [Extensible List]	NAV [Member]	NAV [Member]
Postretirement Benefit Plan [Member] | Other Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	$ 3	$ 3
Postretirement Benefit Plan [Member] | Fair Value, Inputs, Level 1, 2 and 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	54	73
Postretirement Benefit Plan [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	0	0
Postretirement Benefit Plan [Member] | Level 1 [Member] | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	0	0
Postretirement Benefit Plan [Member] | Level 1 [Member] | Debt Security, Government, Non-US [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	0	0
Postretirement Benefit Plan [Member] | Level 1 [Member] | Corporate Debt Security, Above Investment Grade [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	0	0
Postretirement Benefit Plan [Member] | Level 1 [Member] | Corporate Debt Security, Below Investment Grade [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	0	0
Postretirement Benefit Plan [Member] | Level 1 [Member] | Other, Net [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	0	0
Postretirement Benefit Plan [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	54	73
Postretirement Benefit Plan [Member] | Level 2 [Member] | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	5	5
Postretirement Benefit Plan [Member] | Level 2 [Member] | Debt Security, Government, Non-US [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	2	3
Postretirement Benefit Plan [Member] | Level 2 [Member] | Corporate Debt Security, Above Investment Grade [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	37	55
Postretirement Benefit Plan [Member] | Level 2 [Member] | Corporate Debt Security, Below Investment Grade [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	7	10
Postretirement Benefit Plan [Member] | Level 2 [Member] | Other, Net [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	3	0
Postretirement Benefit Plan [Member] | NAV [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, net	$ 65	$ 109