Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Nov. 25, 2016	Nov. 27, 2015	Nov. 25, 2016	Nov. 27, 2015
Income Taxes [Line Items]
Effective tax rate	26.00%	31.50%	31.70%	31.70%
Unrecognized tax benefit due to the issuance of regulations that clarified the law and the expiration of statute		$ 4,300,000		$ 4,300,000
Tax on unrealized investment gains (losses) accounted for in other comprehensive income			$ 8,800,000	$ 16,400,000
Description of prior-period information retrospectively adjusted			In November 2015, the FASB issued ASU 2015-17, “Balance Sheet Classification of Deferred Taxes,” which simplifies the presentation of deferred income taxes. This ASU requires that deferred tax assets and liabilities be classified as non-current in a statement of financial position. The Corporation early adopted ASU 2015-17 during the fourth quarter of 2016 on a prospective basis. Adoption of ASU 2015-17 resulted in a reclassification of the Corporation’s net current deferred tax asset to the net non-current deferred tax asset in the Corporation’s Consolidated Statement of Financial Position as of February 29, 2016. No prior periods were retrospectively adjusted.
Unrecognized tax benefits	$ 16,100,000		$ 16,100,000
Effect on income tax expense if unrecognized tax benefits are recognized	14,400,000		14,400,000
Decrease in unrecognized tax benefits	400,000		400,000
Accrued Interest and penalties on unrecognized tax benefit	$ 1,600,000		1,600,000
Accounting Standards Update 2015-17 [Member]
Income Taxes [Line Items]
Prior period reclassification adjustment			$ 0