INCOME TAXES - Narrative (Details) $ in Thousands	12 Months Ended
Jan. 31, 2026 USD ($)	Jan. 31, 2025 USD ($)	Jan. 31, 2024 USD ($)	Jan. 31, 2023 USD ($)
Operating Loss Carryforwards [Line Items]
Valuation allowance	$ 32,400	$ 39,100	$ 69,900
Federal	841,500	805,000
State	702,200	628,600
Foreign	19,800	20,000
Not subject to expiration	$ 826,400	$ 789,900
Carryforwards on taxable income (in percent)	0.80	0.80
Subject to expiration	$ 15,100	$ 15,100
Unrecognized tax benefits	10,904	9,457	8,783	$ 7,477
Unrecognized tax benefits that would impact effective tax rate	2,300	1,900	$ 2,400
Penalties and interest accrued	600	400
Domestic Tax Jurisdiction
Operating Loss Carryforwards [Line Items]
Federal net operating loss carryforward	841,500	805,000
Domestic Tax Jurisdiction \| Research Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Tax credit carryforward, amount	17,000	15,500
State and Local Jurisdiction \| Research Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Tax credit carryforward, amount	$ 13,200	$ 11,100

Operating Loss Carryforwards Limitation On Taxable Income, Percent

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local operating loss carryforwards.

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-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are not subject to expiration dates.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are subject to expiration dates.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of unrecognized tax benefits.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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