v3.25.3

INCOME TAXES (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
INCOME TAXES (Details) - USD ($) $ in Millions	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Income Tax Contingency
Effective income tax rate (as a percent)	(0.40%)	(2.30%)	(0.60%)	(1.60%)
Unrecognized tax benefits	$ 83.6		$ 83.6
Unrecognized tax benefits that would impact effective tax rate	74.4		74.4
Accrued interest and penalties related to unrecognized tax benefits	1.3		1.3
Deferred tax assets, gross	5.3		5.3
Deferred tax assets, valuation allowance	5.2		5.2
Deferred tax assets, net of valuation allowance	0.1		0.1
Other long-term assets
Income Tax Contingency
Unrecognized tax benefits	76.0		76.0
Other long-term liabilities
Income Tax Contingency
Unrecognized tax benefits	$ 7.6		$ 7.6

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

+ References

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations.

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Amount of unrecognized tax benefits.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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QUANTUM CORP /DE/ 10-Q