Description of Business, Basis of Presentation and Summary of Significant Accounting Policies - Schedule of self insurance liabilities (Details) - USD ($) $ in Millions	12 Months Ended
Feb. 24, 2018	Feb. 25, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Beginning balance	$ 1,264.9	$ 1,320.8
Expense	314.4	281.7
Claim payments	(287.6)	(279.6)
Other reductions	(74.0)	(58.0)
Ending balance	1,217.7	1,264.9
Less current portion	(296.0)	(293.3)
Long-term portion	$ 921.7	$ 971.6

Self Insurance Reserve, Claim Payments

No definition available.

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Balance Type:	debit
Period Type:	duration

- Definition

Self Insurance Reserve, Expense

+ References

No definition available.

+ Details

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- Definition

Self Insurance Reserve, Increase (Decrease) From Other Adjustments

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Carrying amount (including both current and noncurrent portions) of accrued known and estimated losses incurred as of the balance sheet date for which no insurance coverage exists, and for which a claim has been made or is probable of being asserted, typically arising from workmen's compensation-type of incidents and personal injury to nonemployees from accidents on the entity's property.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.24)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_SelfInsuranceReserve
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Period Type:	instant

- Definition

Carrying amount of accrued known and estimated losses incurred as of the balance sheet date for which no insurance coverage exists, and for which a claim has been made or is probable of being asserted, typically arising from workmen's compensation-type of incidents and personal injury to nonemployees from accidents on the entity's property that are expected to be paid within one year (or the normal operating cycle, if longer).

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Carrying amount of accrued known and estimated losses incurred as of the balance sheet date for which no insurance coverage exists, and for which a claim has been made or is probable of being asserted, typically arising from workmen's compensation-type of incidents and personal injury to nonemployees from accidents on the entity's property that are expected to be paid after one year (or the normal operating cycle, if longer).

+ References

No definition available.

+ Details

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