Asset Impairment, Restructuring and Other Special Charges - Narrative (Details) $ in Millions	1 Months Ended		3 Months Ended	9 Months Ended		12 Months Ended
	Nov. 30, 2021 position	Jan. 31, 2021 position	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2021 restructuring_program
Restructuring Cost and Reserve [Line Items]
Number of restructuring programs announced | restructuring_program							2
Expected payment term				12 months
Forecast
Restructuring Cost and Reserve [Line Items]
Cash paid						$ 34
January 2021 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Expected number of positions eliminated | position		315
Restructuring costs			$ 1		$ 44
November 2021 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Expected number of positions eliminated | position	380
Restructuring reserve, accrual adjustment				$ 9