Reporting Segment Information - Schedule of Segment Reporting Information, by Operating Segment (Detail) - USD ($) $ in Thousands	4 Months Ended
Apr. 20, 2019	Apr. 21, 2018	Dec. 29, 2018
Segment Reporting Information [Line Items]
Net sales	$ 2,542,375	$ 2,385,073
Merger/acquisition and integration	782	2,206
Restructuring charges (gains) and asset impairment	(5,662)	6,202
Depreciation and amortization	26,632	25,237
Operating earnings (loss)	22,209	25,748
Capital expenditures	16,006	21,041
Total Assets	2,359,496		$ 1,971,912
Discontinued Operations [Member]
Segment Reporting Information [Line Items]
Total Assets	3,090		3,151
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	2,542,375	2,385,073
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales	(288,408)	(253,324)
Food Distribution [Member]
Segment Reporting Information [Line Items]
Net sales	1,169,238	1,155,211
Merger/acquisition and integration	(130)	2,195
Restructuring charges (gains) and asset impairment	(6,343)	1,260
Depreciation and amortization	10,233	9,540
Operating earnings (loss)	24,592	24,521
Capital expenditures	4,249	12,445
Total Assets	1,156,089		1,074,125
Food Distribution [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	1,169,238	1,155,211
Food Distribution [Member] \| Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales	(288,408)	(253,324)
Military [Member]
Segment Reporting Information [Line Items]
Net sales	671,370	663,620
Merger/acquisition and integration		4
Depreciation and amortization	3,597	3,678
Operating earnings (loss)	(1,557)	1,513
Capital expenditures	1,142	254
Total Assets	428,518		405,587
Military [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	671,370	663,620
Retail [Member]
Segment Reporting Information [Line Items]
Net sales	701,767	566,242
Merger/acquisition and integration	912	7
Restructuring charges (gains) and asset impairment	681	4,942
Depreciation and amortization	12,802	12,019
Operating earnings (loss)	(826)	(286)
Capital expenditures	10,615	8,342
Total Assets	771,799		$ 489,049
Retail [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales	$ 701,767	$ 566,242

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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