Pension and Other Postretirement Benefits - Narrative (Details) £ in Millions, $ in Millions	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2022 GBP (£)	Sep. 30, 2022 GBP (£)
Retirement Benefits [Abstract]
Settlement charge		$ 1,511
Expected contributions	$ 141			$ 141		$ 141		£ 127
Employer contributions						$ 104	£ 93
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Recognized prior service credit	$ 5		$ 6	$ 15	$ 19