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Restructuring, Impairment, and Related Charges - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring, impairment, and related charges recognized	$ 18	$ 155	$ 208	$ 271
Restructuring, impairment, and related charges	18	40	208	156
International (1)
Restructuring Cost and Reserve [Line Items]
Impairment, Long-Lived Asset, Held-for-Use		115		115
Restructuring, impairment, and related charges		131		189
Restructuring Plan - Remote Work Transitioning
Restructuring Cost and Reserve [Line Items]
Restructuring, impairment, and related charges	5		115
Restructuring Plan - Remote Work Transitioning \| Minimum \| Restructuring Type, Exit Related Costs, Accelerated Depreciation, Amortization and Asset Impairments
Restructuring Cost and Reserve [Line Items]
Expected total pre-tax charges	140		140
Restructuring Plan - Remote Work Transitioning \| Maximum \| Restructuring Type, Exit Related Costs, Accelerated Depreciation, Amortization and Asset Impairments
Restructuring Cost and Reserve [Line Items]
Expected total pre-tax charges	$ 180		$ 180
Operating Model and Cost Optimization Programs \| International (1)
Restructuring Cost and Reserve [Line Items]
Restructuring, impairment, and related charges		$ 9		$ 50