Acquisitions (Schedule of Purchase Price Allocation - Food Lion Supermarket Stores) (Detail) - USD ($) $ in Thousands	9 Months Ended
Sep. 24, 2016	Sep. 26, 2015
Total cash paid	$ 47,547	$ 0
Food Lion, LLC [Member]
Other long-term assets - Escrow payment made towards remaining 28 stores	15,105
Total cash paid	23,227
First Ten Stores Acquired [Member]
Inventories	1,958
Prepaid expenses	433
Accounts payable and other liabilities	(66)
Property and equipment	5,719
Other	78
Total cash paid	$ 8,122

Amount of other assets expected to be realized or consumed before one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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The amount of inventory recognized as of the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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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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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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