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Hedging Activities - Schedule of Derivative Instruments Gain (Loss) (Details) - USD ($) | 12 Months Ended
--- | ---
Mar. 31, 2026 | Mar. 31, 2025 | Mar. 31, 2024
Derivatives, Fair Value [Line Items] |  |  |
Derivatives designated as cash flow and other hedges: |  | $ 0 | $ 0
Derivatives designated for hedge accounting | Net Investment Hedging | Cross-currency swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivatives designated as net investment hedges: | $ (142,000,000) | 80,000,000 | 3,000,000
Derivatives designated for hedge accounting | Cash Flow Hedging | Cross-currency swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivatives designated as cash flow and other hedges: | 0 |  |
Derivatives designated for hedge accounting | Cash Flow Hedging | Foreign currency forwards |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivatives designated as cash flow and other hedges: | 12,000,000 |  | $ 0
Derivatives designated for hedge accounting | Cash Flow Hedging | Fixed interest rate swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivatives designated as cash flow and other hedges: | $ 0 | $ 0 |

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- Definition Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 182 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480401/815-10-55-182 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4C -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4C Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-11 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 15 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-15 + Details
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