Pension Plans, Postretirement and Other Employee Benefits - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension and Other Postretirement Benefits Disclosure [Line Items]
Expense recorded relating to employee matching contribution	$ 78	$ 77	$ 76
Curtailment gain (loss)		21
Non-cash settlement charge		6
Acceptable tolerance limit of investment allocations for securities	5.00%
Pension Plans
Pension and Other Postretirement Benefits Disclosure [Line Items]
Accumulated benefit obligation	$ 2,247	2,446
Other Postretirement Benefits Plans
Pension and Other Postretirement Benefits Disclosure [Line Items]
Expected contributions in 2020	18
Pension benefit obligations	82	81
Increase (decrease) plan amendments	(20)	(59)
Increase (decrease) in AOCI	20	57	13
Increase in AOCI (net of tax)	0	0	4
Curtailment gain (loss)	0	21	7
Non-cash settlement charge	0	0	0
Other Postretirement Benefits Plans \| FM OPEB Plan
Pension and Other Postretirement Benefits Disclosure [Line Items]
Increase (decrease) plan amendments	$ (20)	(57)	(17)
U.S. \| Equity securities
Pension and Other Postretirement Benefits Disclosure [Line Items]
Targeted pension plan allocations in debt securities	54.00%
U.S. \| Fixed income securities
Pension and Other Postretirement Benefits Disclosure [Line Items]
Targeted pension plan allocations in debt securities	46.00%
U.S. \| Pension Plans
Pension and Other Postretirement Benefits Disclosure [Line Items]
Expected contributions in 2020	$ 4
Increase (decrease) plan amendments	0	1
Curtailment gain (loss)	0	0	0
Non-cash settlement charge	$ 0	$ (1)	(6)
Non-cash charge			$ 5
Weighted average return on assets	5.60%	6.20%
Expected long-term return on plan assets	6.20%	6.30%	6.30%
Non-U.S.
Pension and Other Postretirement Benefits Disclosure [Line Items]
Expected long-term return on plan assets	2.70%	2.90%
Non-U.S. \| Pension Plans
Pension and Other Postretirement Benefits Disclosure [Line Items]
Expected contributions in 2020	$ 46
Increase (decrease) plan amendments	0	$ 0
Curtailment gain (loss)	0	0	$ 0
Non-cash settlement charge	$ (1)	$ (6)	$ (1)
Expected long-term return on plan assets	2.90%	3.50%	4.00%

Acceptable tolerance limit of investment allocations for securities.

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Defined plan benefit obligation.

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Pension and Other Postretirement Benefits Disclosure [Line Items]

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Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Weighted average rate of return on plan assets, used to determine net periodic benefit cost (credit) of defined benefit plan, in subsequent interim measurement.

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Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

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Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

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Amount of increase (decrease) in benefit obligation of defined benefit plan from change in terms of existing plan or initiation of new plan.

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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Amount of gain (loss) recognized in net periodic benefit (cost) credit from event reducing expected years of future service of present employees or eliminating accrual of defined benefits for some or all future services of present employees.

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Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

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The amount of plan compensation cost recognized during the period.

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Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan, attributable to parent.

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Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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Amount of noncash expense (reversal of expense) for pension benefits. Excludes other postretirement benefits.

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