Pension Benefits - Schedule Of Net Periodic Expense For Pension Plans (Details) - Pension Plans, Defined Benefit - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
United States
Defined Benefit Plan Disclosure [Line Items]
Service cost - benefits earned during the year	$ 0	$ 0	$ 3
Interest cost on projected benefit obligation	6	14	14
Expected return on assets	(4)	(16)	(19)
Amortization of unrecognized actuarial loss and prior service costs	2	5	6
Curtailment/settlement loss	127	4	2
Net periodic pension expense	131	7	6
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost - benefits earned during the year	16	15	15
Interest cost on projected benefit obligation	19	21	22
Expected return on assets	(22)	(23)	(26)
Amortization of unrecognized actuarial loss and prior service costs	6	4	5
Curtailment/settlement loss	0	1	1
Net periodic pension expense	$ 19	$ 18	$ 17