Income Taxes - Operating loss carryforwards (Details) $ in Thousands	Feb. 29, 2020 USD ($)
Operating Loss Carryforwards [Line Items]
Deferred tax asset for operating loss carryforwards expiring in years 2030 through 2037	$ 53,184
Deferred tax asset for operating loss carryforwards that have indefinite expiration	22,923
U.S. federal
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	272,804
U.S. states
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 258,875

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

No definition available.

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- Definition

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

+ 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
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319

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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

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