Income Taxes - Net Deferred Tax Assets (Detail) (USD $) In Thousands, unless otherwise specified	Feb. 28, 2015	Feb. 28, 2014
Income Tax Disclosure [Abstract]
Deferred and refundable income taxes (current)	$ 40,543	$ 43,589
Deferred and refundable income taxes (noncurrent)	86,030	70,261
Deferred income taxes and noncurrent income taxes payable	(17)	(596)
Net deferred tax assets	$ 126,556us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 113,254us-gaap_DeferredTaxAssetsLiabilitiesNet

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences expected to be realized or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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Gross amount of noncurrent deferred tax liabilities, which result from applying the applicable tax rate to taxable temporary differences pertaining to each jurisdiction to which the entity is obligated to pay income tax.

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