Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
May 27, 2016	May 29, 2015
Income Tax Disclosure [Abstract]
Effective tax rate	32.60%	34.60%
Tax on unrealized investment gains (losses) accounted for in other comprehensive income	$ 4.9	$ 28.5
Unrecognized tax benefits	17.1
Effect on income tax expense if unrecognized tax benefits are recognized	15.4
Decrease in unrecognized tax benefits	1.4
Accrued Interest and penalties on unrecognized tax benefit	$ 1.7

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32698-109319

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Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

+ References

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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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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