Long-term Debt and Capitalized Lease Obligations - Narrative (Details) - USD ($)	Sep. 08, 2018	Feb. 24, 2018
Debt Instrument [Line Items]
Debt covenant - maximum cumulative distributions limit as a percentage of total assets	4.00%
Outstanding balance on letters of credit	$ 183,000,000.0	$ 205,600,000
Capitalized lease obligations	818,500,000	864,600,000
Current maturities of capitalized lease obligations	104,100,000	102,100,000
Long-term maturities of capitalized lease obligations	714,400,000	762,500,000
LOC Sub-facility
Debt Instrument [Line Items]
Outstanding balance on letters of credit	547,600,000	576,800,000
Line of credit \| Asset-Based Loan Facility
Debt Instrument [Line Items]
Outstanding balance on line of credit	0	$ 0
Maximum
Debt Instrument [Line Items]
Debt covenant - maximum cumulative distributions limit	$ 1,000,000,000.0

Debt Instrument, Covenant, Cumulative Distribution Allowable, Percentage of Total Assets

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Debt Instrument, Covenant, Cumulative Distributions Allowable

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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