Employee Benefit Plans (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Components of Net Periodic Benefit Costs:
Defined benefit pension cost	$ 0	$ 24,000,000
Forecast
Contributions [Abstract]
Expected reduction in defined contribution plan expense			$ 20,000,000
Pension Plan
Contributions [Abstract]
Defined benefit plan, contributions by employer	35,000,000	33,000,000		$ 139,000,000
Defined benefit plan, expected future employer contributions				130,000,000
Pension Plan | U.S.
Components of Net Periodic Benefit Costs:
Service cost	0	1,000,000
Interest cost	18,000,000	23,000,000
Expected return on plan assets	(28,000,000)	(26,000,000)
Recognized net actuarial loss	5,000,000	7,000,000
Amortization of prior service credit	0	0
Recognized settlement loss	15,000,000	19,000,000
Recognized curtailment gain	0	0
Defined benefit pension cost	10,000,000	24,000,000
Defined contribution plans	0	5,000,000
Net Periodic Benefit Cost (Credit)	10,000,000	29,000,000
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss):
Net actuarial loss (gain)	(44,000,000)	12,000,000
Amortization of net actuarial (loss) gain	(20,000,000)	(26,000,000)
Amortization of net prior service credit	0	0
Total Recognized in Other Comprehensive Income (Loss)	(64,000,000)	(14,000,000)
Total Recognized in Net Periodic Benefit (Credit) Cost and Other Comprehensive Income (Loss)	(54,000,000)	15,000,000
Contributions [Abstract]
Defined benefit plan, contributions by employer	6,000,000	6,000,000		35,000,000
Defined benefit plan, expected future employer contributions				25,000,000
Pension Plan | U.S. | Qualified Plan
Contributions [Abstract]
Mandatory future contributions	0
Pension Plan | Non-U.S.
Components of Net Periodic Benefit Costs:
Service cost	5,000,000	5,000,000
Interest cost	22,000,000	29,000,000
Expected return on plan assets	(52,000,000)	(47,000,000)
Recognized net actuarial loss	15,000,000	14,000,000
Amortization of prior service credit	0	0
Recognized settlement loss	0	0
Recognized curtailment gain	0	(1,000,000)
Defined benefit pension cost	(10,000,000)	0
Defined contribution plans	5,000,000	5,000,000
Net Periodic Benefit Cost (Credit)	(5,000,000)	5,000,000
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss):
Net actuarial loss (gain)	1,000,000	0
Amortization of net actuarial (loss) gain	(15,000,000)	(14,000,000)
Amortization of net prior service credit	0	0
Total Recognized in Other Comprehensive Income (Loss)	(14,000,000)	(14,000,000)
Total Recognized in Net Periodic Benefit (Credit) Cost and Other Comprehensive Income (Loss)	(19,000,000)	(9,000,000)
Contributions [Abstract]
Defined benefit plan, contributions by employer	29,000,000	27,000,000		104,000,000
Defined benefit plan, expected future employer contributions				105,000,000
Retiree Health
Components of Net Periodic Benefit Costs:
Service cost	1,000,000	1,000,000
Interest cost	2,000,000	2,000,000
Expected return on plan assets	0	0
Recognized net actuarial loss	0	0
Amortization of prior service credit	(17,000,000)	(19,000,000)
Recognized settlement loss	0	0
Recognized curtailment gain	0	0
Defined benefit pension cost	(14,000,000)	(16,000,000)
Net Periodic Benefit Cost (Credit)	(14,000,000)	(16,000,000)
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss):
Net actuarial loss (gain)	0	0
Amortization of net actuarial (loss) gain	0	0
Amortization of net prior service credit	17,000,000	19,000,000
Total Recognized in Other Comprehensive Income (Loss)	17,000,000	19,000,000
Total Recognized in Net Periodic Benefit (Credit) Cost and Other Comprehensive Income (Loss)	3,000,000	3,000,000
Contributions [Abstract]
Defined benefit plan, contributions by employer	$ 6,000,000	$ 5,000,000		25,000,000
Defined benefit plan, expected future employer contributions				$ 30,000,000