Supplemental Disclosures to the Consolidated Statements of Cash Flows - Narrative (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Oct. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Loss Contingencies [Line Items]
Litigation settlement, expense			$ 30
Risk and Insurance Services | Guy Carpenter
Loss Contingencies [Line Items]
Gain from the settlement	$ 58	$ 58
Litigation settlement, expense	$ 10