Company pension investments which are categorized as level three assets percentage.

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- Definition

Expected annual standard deviation in returns of the target portfolio which reflects both the equity allocation and the diversification benefits among the asset classes in which the portfolio invests.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

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.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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- Definition

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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- Definition

Amount of cost for defined contribution plan.

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Pension and Other Postretirement Benefit Plans - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation		$ 26,400	$ 22,800
Employer contributions to defined contribution savings plans		$ 166	$ 149	$ 136
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Percentage of Company's pension investments categorized as Level 3 assets (as percent)		4.00%	4.00%
Pension Benefits \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 942	$ 860
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		1,221	1,102	$ 968
Expected contributions to the pension plans and other postretirement benefit plans during next fiscal year		35
Other Postretirement Benefits \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 0	$ 0
United States
Defined Benefit Plan Disclosure [Line Items]
Expected annual standard deviation in returns of the target portfolio which reflects both the equity allocation and the diversification benefits among the asset classes in which the portfolio invests (as percent)		11.00%
Expected rate of return on plan assets (as percent)		7.30%	8.10%	8.20%
United States \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets (as percent)		7.00%
United States \| Minimum \| Forecast
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets (as percent)	6.50%
United States \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets (as percent)		7.30%
United States \| Maximum \| Forecast
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets (as percent)	6.70%
United States \| U.S. equities \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target allocation (as percent)		30.00%
United States \| U.S. equities \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target allocation (as percent)		45.00%
United States \| International equities \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target allocation (as percent)		15.00%
United States \| International equities \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target allocation (as percent)		30.00%
United States \| Fixed Income Investments \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target allocation (as percent)		35.00%
United States \| Fixed Income Investments \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target allocation (as percent)		45.00%
United States \| Cash And Other Investments \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target allocation (as percent)		5.00%
United States \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation		$ 14,400	$ 12,800
Fair value of plan assets		12,672	11,361	$ 9,648
Expected contributions to the pension plans and other postretirement benefit plans during next fiscal year		300
United States \| Pension Benefits \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		7	9	13
International \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		12,049	$ 10,163	$ 8,580
Expected contributions to the pension plans and other postretirement benefit plans during next fiscal year		$ 170
Expected rate of return on plan assets (as percent)		4.40%	4.90%	5.10%
International \| Pension Benefits \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 935	$ 851	$ 813