Income Taxes (Unrecognized Tax Benefits Reconciliation) (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance of unrecognized tax benefits	$ 68	$ 80	$ 73
Additions based on tax positions related to the current period	5	5	9
Additions based on tax positions of prior years(1)	7	6	12
Reductions based on tax positions of prior years (2)	5	17	4
Settlements (3)	5	6	10
Foreign exchange	4	0	0
Ending Balance of unrecognized tax benefits	74	68	80
Income Tax Details [Line Items]
Additions based on tax positions related to the current period	5	5	9
Reductions based on tax positions of prior years (2)	5	17	4
Settlements (3)	5	6	$ 10
Germany
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Reductions based on tax positions of prior years (2)	12
Settlements (3)	3	10
Income Tax Details [Line Items]
Reductions based on tax positions of prior years (2)	12
Settlements (3)	$ 3	$ 10

Unrecognized Tax Benefits, Net Changes Resulting from Foreign Currency Translation

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Amount of unrecognized tax benefits.

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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 217
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482663/740-10-55-217

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-15A

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 10B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482525/740-10-45-10B

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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