Retirement Benefits - Status (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Pension Plan
Plan Contributions [Abstract]
Payment for Pension and Other Postretirement Benefits	$ 567
Pension and Other Postretirement Benefit Contributions Unfunded Plans	379
Pension And Other Postretirement Expected Benefit Contributions Unfunded Plans	400
Pension Plan | Minimum
Plan Contributions [Abstract]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	500
Pension Plan | Maximum
Plan Contributions [Abstract]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	600
Pension Plan | U.S. Plans
Change in Benefit Obligation
Benefit obligation at January 1	44,888	$ 49,020
Service cost	500	526	$ 520
Interest cost	1,054	928	1,291
Amendments	0	0
Separation programs/other	4	(25)
Curtailments	0	0
Settlements	(1,172)	(1,297)
Plan participant contributions	18	20
Benefits paid	(2,466)	(2,522)
Foreign exchange translation	0	0
Actuarial (gain)/loss	(9,959)	(1,762)
Benefit obligation at December 31	32,867	44,888	49,020
Change in Plan Assets
Fair value of plan assets at January 1	45,909	48,355
Actual return on plan assets	(9,548)	1,150
Company contributions	223	247
Plan participant contributions	18	20
Benefits paid	(2,466)	(2,522)
Settlements	(1,172)	(1,297)
Foreign exchange translation	0	0
Defined Benefit Plan Other Increase Decrease Plan Assets	(42)	(44)
Fair value of plan assets at December 31	32,922	45,909	48,355
Funded status at December 31	55	1,021
Amounts Recognized on the Balance Sheet
Prepaid assets	2,064	3,130
Accrued liabilities	(2,009)	(2,109)
Total	55	1,021
Amounts Recognized in Accumulated Other Comprehensive Loss (pre-tax)
Unamortized prior service costs/(credits)	0	2
Pension Plans in which Accumulated Benefit Obligation Exceeds Plan Assets at December 31
Accumulated benefit obligation	15,055	2,192
Fair value of plan assets	13,576	140
Accumulated Benefit Obligation at December 31	32,336	43,879
Pension Plans in which Projected Benefit Obligation Exceeds Plan Assets at December 31
Projected benefit obligation	15,585	2,249
Fair value of plan assets	13,576	140
Expected Future Benefit Payments and Amortization
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	3,805
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	2,595
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	2,605
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	2,570
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	2,530
Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Year Thereafter	12,445
Pension Plan | U.S. Plans | Alternatives
Change in Plan Assets
Fair value of plan assets at January 1	6,690
Fair value of plan assets at December 31	6,306	6,690
Pension Plan | U.S. Plans | Hedge Funds
Change in Plan Assets
Fair value of plan assets at January 1	3,390
Fair value of plan assets at December 31	3,342	3,390
Pension Plan | U.S. Plans | Private Equity Funds
Change in Plan Assets
Fair value of plan assets at January 1	1,977
Fair value of plan assets at December 31	1,411	1,977
Pension Plan | Non-U.S. Plans
Change in Benefit Obligation
Benefit obligation at January 1	34,432	39,835
Service cost	416	557	529
Interest cost	504	420	514
Amendments	0	4
Separation programs/other	56	185
Curtailments	(2)	(4)
Settlements	(674)	0
Plan participant contributions	12	13
Benefits paid	(1,302)	(1,565)
Foreign exchange translation	(2,877)	(1,432)
Actuarial (gain)/loss	(8,960)	(3,581)
Benefit obligation at December 31	21,605	34,432	39,835
Change in Plan Assets
Fair value of plan assets at January 1	33,085	33,820
Actual return on plan assets	(7,516)	788
Company contributions	722	912
Plan participant contributions	12	13
Benefits paid	(1,302)	(1,565)
Settlements	(674)	0
Foreign exchange translation	(2,973)	(855)
Defined Benefit Plan Other Increase Decrease Plan Assets	(10)	(28)
Fair value of plan assets at December 31	21,344	33,085	33,820
Funded status at December 31	(261)	(1,347)
Amounts Recognized on the Balance Sheet
Prepaid assets	3,599	5,404
Accrued liabilities	(3,860)	(6,751)
Total	(261)	(1,347)
Amounts Recognized in Accumulated Other Comprehensive Loss (pre-tax)
Unamortized prior service costs/(credits)	130	170
Pension Plans in which Accumulated Benefit Obligation Exceeds Plan Assets at December 31
Accumulated benefit obligation	8,346	12,586
Fair value of plan assets	5,068	6,835
Accumulated Benefit Obligation at December 31	20,304	31,850
Pension Plans in which Projected Benefit Obligation Exceeds Plan Assets at December 31
Projected benefit obligation	8,932	13,651
Fair value of plan assets	5,068	6,900
Expected Future Benefit Payments and Amortization
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	1,300
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	1,225
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	1,245
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	1,255
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	1,275
Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Year Thereafter	6,485
Pension Plan | Non-U.S. Plans | Alternatives
Change in Plan Assets
Fair value of plan assets at January 1	2,363
Fair value of plan assets at December 31	1,998	2,363
Pension Plan | Non-U.S. Plans | Hedge Funds
Change in Plan Assets
Fair value of plan assets at January 1	1,221
Fair value of plan assets at December 31	1,009	1,221
Pension Plan | Non-U.S. Plans | Private Equity Funds
Change in Plan Assets
Fair value of plan assets at January 1	756
Fair value of plan assets at December 31	584	756
Worldwide OPEB
Change in Benefit Obligation
Benefit obligation at January 1	6,040	6,575
Service cost	42	49	47
Interest cost	146	127	169
Amendments	0	0
Separation programs/other	0	0
Curtailments	0	0
Settlements	0	0
Plan participant contributions	1	21
Benefits paid	(363)	(356)
Foreign exchange translation	(92)	0
Actuarial (gain)/loss	(1,315)	(376)
Benefit obligation at December 31	4,459	6,040	6,575
Change in Plan Assets
Fair value of plan assets at January 1	0	0
Actual return on plan assets	0	0
Company contributions	0	0
Plan participant contributions - Worldwide OPEB	0	0
Benefits paid - Worldwide OPEB	0	0
Settlements	0	0
Foreign exchange translation	0	0
Defined Benefit Plan Other Increase Decrease Plan Assets	0	0
Fair value of plan assets at December 31	0	0	$ 0
Funded status at December 31	(4,459)	(6,040)
Amounts Recognized on the Balance Sheet
Prepaid assets	0	0
Accrued liabilities	(4,459)	(6,040)
Total	(4,459)	(6,040)
Amounts Recognized in Accumulated Other Comprehensive Loss (pre-tax)
Unamortized prior service costs/(credits)	25	$ 22
Expected Future Benefit Payments and Amortization
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	335
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	335
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	335
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	330
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	330
Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Year Thereafter	$ 1,595