Retirement Benefits - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Aug. 26, 2016	Aug. 28, 2015	Aug. 26, 2016	Aug. 28, 2015	Feb. 29, 2016
Defined Contribution Plan Disclosure [Line Items]
Liability for postretirement benefits other than pensions	$ 18.9	$ 19.2	$ 18.9	$ 19.2	$ 17.8
Long-term liability for pension benefits	77.9	78.6	77.9	78.6	$ 80.2
Profit-Sharing and Benefit Plan 401 (k) [Member] | United States [Member]
Defined Contribution Plan Disclosure [Line Items]
Employer's contributions to a defined contribution retirement plan	$ 3.4	$ 3.0	$ 8.5	$ 5.9