Income Taxes (Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Millions	Mar. 31, 2017	Mar. 31, 2016
Deferred income tax assets:
Provisions not currently deductible for tax purposes	$ 459	$ 396
Tax losses/benefit carryforwards, net	724	741
Depreciation and amortization	45	41
Other assets	4	(1)
Total deferred income tax assets	1,232	1,177
Less: valuation allowance	(680)	(613)
Net deferred income tax assets	552	564
Deferred income tax liabilities:
Depreciation and amortization	442	457
Inventory valuation reserves	84	64
Monetary exchange gains, net	14	15
Other liabilities	24	30
Total deferred income tax liabilities	564	566
Net deferred income tax liabilities	$ 12	$ 2