Summary of Significant Accounting Policies Environmental Contingencies (Details) - USD ($) $ in Millions	Feb. 22, 2019	Feb. 23, 2018
Accounting Policies [Abstract]
Accrual for Environmental Loss Contingencies, Discount Rate		3.50%
Accrued Environmental Loss Contingencies, Current	$ 0.7	$ 0.7
Accrued Environmental Loss Contingencies, Noncurrent	2.4	2.5
Accrual for Environmental Loss Contingencies, Gross	$ 3.1	$ 3.2

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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-Topic 410
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Rate applied to the undiscounted amount of environmental loss contingencies to arrive at the present value recorded as of the balance sheet date.

+ References

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Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable after twelve months or beyond the next operating cycle if longer.

+ References

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