Income Tax Expense (Benefit), Excess Tax Deductions, Foreign Employees

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

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- Definition

Amount of reasonable estimate for income tax expense for which accounting for tax effect for remeasurement of deferred tax asset from change in tax rate is incomplete pursuant to Tax Cuts and Jobs Act.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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-Topic 740
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- Definition

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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 20
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Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
Income Taxes - Narrative (Details) - USD ($)	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Income tax benefit, excess tax deduction, foreign employees			$ 1,300,000
Increase in valuation allowance	$ 157,700,000	$ 86,600,000
Reduction in deferred tax asset before valuation allowance due to change in tax rate		56,500,000
Accrued penalties and interest related to unrecognized tax benefits	0	$ 0
Domestic Tax Authority
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating loss carryforwards	1,462,600,000
Domestic Tax Authority \| Research Tax Credit Carryforward
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Tax credit carryforward	35,300,000
State and Local Jurisdiction
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating loss carryforwards	919,500,000
State and Local Jurisdiction \| Research Tax Credit Carryforward
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Tax credit carryforward	23,400,000
State and Local Jurisdiction \| California Enterprise Zone Credit
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Tax credit carryforward	1,000,000.0
UNITED KINGDOM
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating loss carryforwards	$ 29,900,000