Other Current Assets and Other Assets - Current (Details) - USD ($) $ in Thousands	Jan. 26, 2019	Jan. 27, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid expenses	$ 12,758	$ 13,167
Insurance recoveries/receivables for accrued insurance claims	0	13,701
Receivables on equipment sales	69	31
Deposits and other current assets, including restricted cash	16,318	12,811
Total other current assets	29,145	39,710
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Income tax receivable	$ 3,461	$ 13,852

No definition available.

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Carrying value of amounts transferred to third parties for security purposes that are expected to be returned or applied towards payment within one year or during the operating cycle, if shorter.

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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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Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

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Amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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Amount of current assets classified as other.

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Amount, after allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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