Defined Benefit Plan, Assumptions Used In Calculation, Period Between Negotiations With Plan Trustee

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- Definition

Defined Benefit Plan, Health Care Cost Trend, Entity's Maximum Trend Rate

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Defined Benefit Plan, Number of Shares of Equity Securities Issued By Employer and Related Parties as Percentage Of Plan Assets

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- Definition

Defined Contribution Plan, Employee Stock Ownership Plan (ESOP), Shares in ESOP, Value

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Guarantor Obligation, Period

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

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Amount of payment, which decreases benefit obligation of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract. Excludes decreases to benefit obligation for remeasurement due to settlement.

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Amount of contribution received by defined benefit plan from employer which increases plan assets.

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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.

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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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Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status.

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- Definition

Number of shares of employer stock in which defined benefit plan asset is invested. Includes, but is not limited to, stock issued or managed by related party of employer.

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- Definition

Amount of plan asset for defined benefit pension plan with projected benefit obligation in excess of plan assets.

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Amount of projected benefit obligation for defined benefit pension plan with projected benefit obligation in excess of plan assets.

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Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

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Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

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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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Ultimate trend rate for health care cost for defined benefit postretirement plan.

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Percentage of actual 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 cost for defined contribution plan.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Retirement Benefits (Narrative) (Details) $ in Millions		1 Months Ended	12 Months Ended
Retirement Benefits (Narrative) (Details) $ in Millions	Jan. 01, 2017	Nov. 30, 2019 GBP (£)	Dec. 31, 2021 USD ($) shares	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Assumed health care cost trend rate for Medicare eligibles and non-Medicare eligibles			4.94%
Future assumed health care cost trend rate			4.36%
Automatic employer contribution of employee's eligible base pay (as a percent)	4.00%
401(k) Plan's assets invested in common stock			$ 742	$ 537
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase (for expense)*			1.85%	1.76%
Post-retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase (for expense)*			0.00%	0.00%
U.S.
Defined Benefit Plan Disclosure [Line Items]
Expected employer contributions, next fiscal year			$ 31
Cost of defined contribution plans			$ 150	$ 145	$ 139
U.S. \| Pension and Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Assumed health care cost trend rate for Medicare eligibles and non-Medicare eligibles			5.50%
Future assumed health care cost trend rate			4.00%
Cap on employer share of health care trend (as a percent)			5.00%
U.S. \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation for plans with accumulated benefit obligations in excess of plan assets			$ 6,600	6,900
Aggregate fair value of plan assets for plans with accumulated benefit obligations in excess of plan assets			5,500	5,100
Projected benefit obligation for plans with projected benefit obligations in excess of plan assets			6,600	6,900
Fair value of plan assets for plans with projected benefit obligations in excess of plan assets			5,500	5,100
Employer contributions			$ 35	65
U.S. \| Post-retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Number of shares held in defined benefit plan (in shares) \| shares			2,000,000
Change in plan assets (as a percent)			6.30%
Employer contributions			$ 3	3
U.S. \| Equities and equity alternatives
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation percentage			60.00%
Actual asset allocation percentage			65.00%
U.S. \| Equities and equity alternatives \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation percentage			56.00%
U.S. \| Equities and equity alternatives \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation percentage			64.00%
U.S. \| Fixed income
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation percentage			40.00%
Actual asset allocation percentage			35.00%
U.S. \| Fixed income \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation percentage			36.00%
U.S. \| Fixed income \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation percentage			44.00%
Non-U.S.
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation for plans with accumulated benefit obligations in excess of plan assets			$ 1,600	3,100
Aggregate fair value of plan assets for plans with accumulated benefit obligations in excess of plan assets			1,200	2,500
Projected benefit obligation for plans with projected benefit obligations in excess of plan assets			1,700	3,300
Fair value of plan assets for plans with projected benefit obligations in excess of plan assets			$ 1,200	$ 2,600
Non-U.S. \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase (for expense)*			2.84%	2.75%
Non-cash settlement charges			$ 5	$ 3	7
Expected employer contributions, next fiscal year			147
Employer contributions			$ 95	$ 78
Non-U.S. \| Post-retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Rate of compensation increase (for expense)*			0.00%	0.00%
Employer contributions			$ 3	$ 2
United Kingdom
Defined Benefit Plan Disclosure [Line Items]
Cost of defined contribution plans			141	$ 121	$ 100
United Kingdom \| Pension Plan Funded Status Guarantee
Defined Benefit Plan Disclosure [Line Items]
Annual deficit contributions (GBP) \| £		£ 450,000,000
Annual deficit contributions, period		7 years
United Kingdom \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Expected employer contributions, next fiscal year			112
Employer contributions			$ 38
Period between legally-prescribed negotiations between the Company and the plans' trustee			3 years
United Kingdom \| Equities and equity alternatives
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation percentage			26.00%
Actual asset allocation percentage			28.00%
United Kingdom \| Equities and equity alternatives \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation percentage			23.00%
United Kingdom \| Equities and equity alternatives \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation percentage			29.00%
United Kingdom \| Fixed income
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation percentage			74.00%
Actual asset allocation percentage			72.00%
United Kingdom \| Fixed income \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation percentage			71.00%
United Kingdom \| Fixed income \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation percentage			77.00%
United Kingdom Pension and Postretirement Benefit Plan, Defined Benefit \| United Kingdom \| Geographic Concentration Risk
Defined Benefit Plan Disclosure [Line Items]
Concentration risk (as a percent)			81.00%