(Fair Values Pension Plan Assets By Asset Class) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount		$ 520
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	$ 12,075		$ 12,018	$ 10,165
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	1,713		3,770
Significant Observable Inputs (Level 2) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	7,349		5,765
Significant Unobservable Inputs (Level 3) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	(5)		8	(5)
Equities – domestic
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	805		1,806
Equities – domestic | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	471		1,037
Equities – domestic | Significant Observable Inputs (Level 2) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	334		769
Equities – domestic | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	0
Equities – domestic | Significant Unobservable Inputs (Level 3) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount			0
Equities – international
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	1,381		2,921
Equities – international | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	976		2,181
Equities – international | Significant Observable Inputs (Level 2) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	405		740
Equities – international | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	0
Equities – international | Significant Unobservable Inputs (Level 3) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount			0
Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	2,249		2,345
Corporate bonds | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	0		0
Corporate bonds | Significant Observable Inputs (Level 2) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	2,249		2,345
Corporate bonds | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	0
Corporate bonds | Significant Unobservable Inputs (Level 3) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount			0
Government securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	5,733		3,377
Government securities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	0		0
Government securities | Significant Observable Inputs (Level 2) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	5,733		3,377
Government securities | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	0
Government securities | Significant Unobservable Inputs (Level 3) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount			0
Mortgage backed securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	126		133
Mortgage backed securities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	0		0
Mortgage backed securities | Significant Observable Inputs (Level 2) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	126		133
Mortgage backed securities | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	0
Mortgage backed securities | Significant Unobservable Inputs (Level 3) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount			0
Other fixed income
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	(1,482)		(1,585)
Other fixed income | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	0		0
Other fixed income | Significant Observable Inputs (Level 2) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	(1,498)		(1,599)
Other fixed income | Significant Unobservable Inputs (Level 3) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	16		14	14
Derivatives
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	(21)		336
Derivatives | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	0		342
Derivatives | Significant Observable Inputs (Level 2) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	0		0
Derivatives | Significant Unobservable Inputs (Level 3) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	(21)		(6)	$ (19)
Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	266		210
Cash and cash equivalents | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	266		210
Cash and cash equivalents | Significant Observable Inputs (Level 2) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	0		0
Cash and cash equivalents | Significant Unobservable Inputs (Level 3) [Member] | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	0		0
Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	1,368		1,112
Private equity
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	721		563
Real estate funds
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets, amount	$ 929		$ 800