Business Optimization Charges - Summary of Business Optimization Charges (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 26	$ 17	$ 58	$ 94
Business Optimization Programs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	26	17	58	94
Costs to implement business optimization programs	6	10	19	32
Accelerated depreciation	0	1	0	5
Total business optimization charges	$ 32	$ 28	$ 77	$ 131

Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

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