CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Foreign currency translation adjustments, tax expense (benefit)	$ (9)	$ (15)	$ (31)	$ (2)
Cash flow hedges adjustments, tax expense (benefit)	0	(1)	6	(1)
Tax expense (benefit) related to available-for-sale securities	(4)	0	(4)	1
Prior service cost, tax	0	0	0	0
Amortization of prior service cost, tax benefit	$ 1	$ 0	$ 3	$ 1

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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- Definition

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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-Publisher FASB
-Name Accounting Standards Codification
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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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-Name Accounting Standards Codification
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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.

+ References

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Amount of tax (expense) benefit for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

+ References

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