CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) (unaudited) (Parenthetical) - USD ($)	3 Months Ended	6 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Foreign currency translation adjustments, tax expense (benefit)	$ (15,000,000)	$ 25,000,000	$ (22,000,000)	$ 13,000,000
Cash flow hedges adjustments, tax expense	3,000,000	0	6,000,000	0
Tax expense related to available-for-sale securities	0	0	0	1,000,000
Amortization of prior service cost, tax benefit	$ 1,000,000	$ 1,000,000	$ 2,000,000	$ 1,000,000

Amount of tax (expense) benefit of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

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Amount, after adjustment, of tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

+ References

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Amount, after reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

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Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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