Goodwill & Other Intangible Assets Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Feb. 24, 2017	Feb. 26, 2016	Feb. 27, 2015
Schedule Of Intangible Assets By Major ClassLine Items [Line Items]
Intangible assets amortization expense	$ 1.0	$ 1.8	$ 1.6
Finite-lived intangible assets, gross	47.2	43.7
Finite-lived intangible assets, accumulated amortization	43.2	42.7
Finite-lived intangible assets, net	4.0	1.0
Indefinite-lived intangible assets, gross	12.8	12.7
Indefinite-lived intangible assets, accumulated amortization	0.0	0.0
Indefinite-lived intangible assets, net	12.8	12.7
Other intangible assets, gross	60.0	56.4
Other intangible assets, net	16.8	$ 13.7
Estimated Amortization Expense, Fiscal Year Maturity [Abstract]
Amortization expense, 2014	0.6
Amortization expense, 2015	0.4
Amortization expense, 2016	0.4
Amortization expense, 2017	0.4
Amortization expense, 2018	0.4
Amortization Expense, 2014-2018 Total	2.2
Proprietary technology [Member]
Schedule Of Intangible Assets By Major ClassLine Items [Line Items]
Weighted average useful life		8 years 3 months
Finite-lived intangible assets, gross	26.8	$ 22.8
Finite-lived intangible assets, accumulated amortization	23.0	22.7
Finite-lived intangible assets, net	3.8	$ 0.1
Trademarks [Member]
Schedule Of Intangible Assets By Major ClassLine Items [Line Items]
Weighted average useful life		10 years
Finite-lived intangible assets, gross	9.0	$ 9.2
Finite-lived intangible assets, accumulated amortization	9.0	9.2
Finite-lived intangible assets, net	0.0	$ 0.0
Non-compete agreements [Member]
Schedule Of Intangible Assets By Major ClassLine Items [Line Items]
Weighted average useful life		5 years 1 month
Finite-lived intangible assets, gross	1.6	$ 1.6
Finite-lived intangible assets, accumulated amortization	1.6	1.4
Finite-lived intangible assets, net	0.0	$ 0.2
Other [Member]
Schedule Of Intangible Assets By Major ClassLine Items [Line Items]
Weighted average useful life		5 years
Finite-lived intangible assets, gross	9.8	$ 10.1
Finite-lived intangible assets, accumulated amortization	9.6	9.4
Finite-lived intangible assets, net	$ 0.2	0.7
Other category [Member]
Schedule Of Intangible Assets By Major ClassLine Items [Line Items]
Intangible asset impairment charges		$ 0.0