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

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Retirement Benefits (Narrative) (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Dec. 31, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Contributions by employer		$ 28	$ 33	$ 141	$ 90
Estimated future employer contributions in current fiscal year		28		28
United States
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, cost recognized		39	37	122	115
United Kingdom
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, cost recognized		$ 31	$ 33	$ 108	$ 106
United Kingdom \| Non-U.S. Plans \| Geographic Concentration Risk
Defined Benefit Plan Disclosure [Line Items]
Concentration risk percentage	81.00%
Equity Funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation, percentage		60.00%		60.00%
Actual asset allocation percentage of equity		61.00%		61.00%
Equity Funds \| United Kingdom
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation, percentage		14.00%		14.00%
Actual asset allocation percentage of equity		17.00%		17.00%
Fixed Income Funds \| United States
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation, percentage		40.00%		40.00%
Actual asset allocation percentage of equity		39.00%		39.00%
Fixed Income Funds \| United Kingdom
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation, percentage		86.00%		86.00%
Actual asset allocation percentage of equity		83.00%		83.00%