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Restructuring Costs - Rollforward of Liability Associated with Cash-based Charges (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2021	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Restructuring Cost and Reserve [Line Items]
Charges incurred	$ 8	$ 17		$ 29	$ 30
Transformation Program [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance			$ 0	11	6	$ 6	$ 1
Charges incurred			2	12		30	28
Cash payments			(1)	(21)		(25)	(23)
Ending Balance	2		1	2		11	6
Transformation Program [Member] \| Real Estate Rationalization [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance				3	$ 6	6
Charges incurred				12		22	27
Cash payments				(15)		(25)	(21)
Ending Balance	0			0		3	6
Transformation Program [Member] \| Technology Modernization [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance				8
Charges incurred						8
Cash payments				(6)
Ending Balance	2			2		$ 8
Transformation Program [Member] \| Process Optimization [Member]
Restructuring Cost and Reserve [Line Items]
Charges incurred							1
Cash payments							(1)
Transformation Program [Member] \| Other [Member]
Restructuring Cost and Reserve [Line Items]
Beginning Balance			0				1
Charges incurred			2
Cash payments			(1)				$ (1)
Ending Balance	$ 0		$ 1	$ 0