Pension Plans, Retirement Benefits and Savings Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension Plans [Member]
Change in projected benefit obligation [Roll Forward]
Benefit obligation, balance, beginning of year	$ 4,591	$ 4,195
Benefits earned	141	133	$ 118
Interest cost on benefit obligation	83	114	141
Actuarial (gain) loss	(75)	356
Benefits paid	(268)	(212)
Amendment	0	1
Foreign currency exchange rate change, change in projected benefit obligation	(1)	4
Benefit obligation, balance, end of year	4,471	4,591	4,195
Change in plan assets [Roll Forward]
Fair value of plan assets, balance, beginning of year	4,756	4,385
Actual return on plan assets	537	570
Company contributions	12	9
Benefits paid	(268)	(212)
Foreign currency exchange rate change, change in plan assets	(1)	4
Fair value of plan assets, balance, end of year	5,036	4,756	4,385
Funded status of plan at end of year	565	165
Amounts recognized in the consolidated balance sheet consist of:
Accrued over-funded benefit plan assets	696	306
Accrued under-funded benefit plan liabilities	(131)	(141)
Total amount recognized in the consolidated balance sheet	565	165
Amounts recognized in accumulated other comprehensive income consist of:
Net actuarial loss (gain)	667	1,113
Prior service cost (benefit)	(1)	(1)
Total amount recognized in accumulated other comprehensive income	666	1,112
Pension Plans [Member] | United States [Member] | Qualified Plan [Member]
Change in projected benefit obligation [Roll Forward]
Benefit obligation, balance, beginning of year	4,326	3,954
Benefits earned	135	128
Interest cost on benefit obligation	79	109
Actuarial (gain) loss	(73)	336
Benefits paid	(255)	(201)
Amendment	0	0
Foreign currency exchange rate change, change in projected benefit obligation	0	0
Benefit obligation, balance, end of year	4,212	4,326	3,954
Change in plan assets [Roll Forward]
Fair value of plan assets, balance, beginning of year	4,631	4,270
Actual return on plan assets	526	562
Company contributions	0	0	0
Benefits paid	(255)	(201)
Foreign currency exchange rate change, change in plan assets	0	0
Fair value of plan assets, balance, end of year	4,902	4,631	4,270
Funded status of plan at end of year	690	305
Amounts recognized in the consolidated balance sheet consist of:
Accrued over-funded benefit plan assets	690	305
Accrued under-funded benefit plan liabilities	0	0
Total amount recognized in the consolidated balance sheet	690	305
Amounts recognized in accumulated other comprehensive income consist of:
Net actuarial loss (gain)	618	1,050
Prior service cost (benefit)	(2)	(2)
Total amount recognized in accumulated other comprehensive income	616	1,048
Nonqualified and Foreign Pension Plans [Member]
Change in projected benefit obligation [Roll Forward]
Benefit obligation, balance, beginning of year	265	241
Benefits earned	6	5
Interest cost on benefit obligation	4	5
Actuarial (gain) loss	(2)	20
Benefits paid	(13)	(11)
Amendment	0	1
Foreign currency exchange rate change, change in projected benefit obligation	(1)	4
Benefit obligation, balance, end of year	259	265	241
Change in plan assets [Roll Forward]
Fair value of plan assets, balance, beginning of year	125	115
Actual return on plan assets	11	8
Company contributions	12	9
Benefits paid	(13)	(11)
Foreign currency exchange rate change, change in plan assets	(1)	4
Fair value of plan assets, balance, end of year	134	125	115
Funded status of plan at end of year	(125)	(140)
Amounts recognized in the consolidated balance sheet consist of:
Accrued over-funded benefit plan assets	6	1
Accrued under-funded benefit plan liabilities	(131)	(141)
Total amount recognized in the consolidated balance sheet	(125)	(140)
Amounts recognized in accumulated other comprehensive income consist of:
Net actuarial loss (gain)	49	63
Prior service cost (benefit)	1	1
Total amount recognized in accumulated other comprehensive income	50	64
Postretirement Benefit Plans [Member]
Change in projected benefit obligation [Roll Forward]
Benefit obligation, balance, beginning of year	171	171
Benefits earned	0	0	0
Interest cost on benefit obligation	3	4	7
Actuarial (gain) loss	(16)	5
Benefits paid	(9)	(10)
Foreign currency exchange rate change, change in projected benefit obligation	0	1
Benefit obligation, balance, end of year	149	171	171
Change in plan assets [Roll Forward]
Fair value of plan assets, balance, beginning of year	11	12
Actual return on plan assets	0	1
Company contributions	7	8
Benefits paid	(9)	(10)
Fair value of plan assets, balance, end of year	9	11	$ 12
Funded status of plan at end of year	(140)	(160)
Amounts recognized in the consolidated balance sheet consist of:
Accrued under-funded benefit plan liabilities	(140)	(160)
Total amount recognized in the consolidated balance sheet	(140)	(160)
Amounts recognized in accumulated other comprehensive income consist of:
Net actuarial loss (gain)	(54)	(41)
Prior service cost (benefit)	(14)	(18)
Total amount recognized in accumulated other comprehensive income	$ (68)	$ (59)