Segment Information (Operations By Lines Of Business) (Details) (USD $)	3 Months Ended	12 Months Ended
Jun. 29, 2013	Sep. 27, 2014	Sep. 28, 2013	Sep. 29, 2012
Segment Reporting Information By Segment [Line Items]
Total revenues from unaffiliated customers		$ 3,835,986,000imkta_Revenue	$ 3,738,540,000imkta_Revenue	$ 3,718,315,000imkta_Revenue
Total income from operations		123,345,157us-gaap_OperatingIncomeLoss	125,574,175us-gaap_OperatingIncomeLoss	123,846,842us-gaap_OperatingIncomeLoss
Other income, net		3,001,161us-gaap_OtherNonoperatingIncomeExpense	2,900,341us-gaap_OtherNonoperatingIncomeExpense	3,527,065us-gaap_OtherNonoperatingIncomeExpense
Interest expense		46,569,864us-gaap_InterestExpense	59,142,378us-gaap_InterestExpense	60,026,564us-gaap_InterestExpense
Loss on early extinguishment of debt	43,100,000		(43,089,248)
Income before income taxes		79,776,454	26,242,890	67,347,343
Total assets		1,656,951,564us-gaap_Assets	1,669,327,737us-gaap_Assets	1,642,109,000us-gaap_Assets
Total capital expenditures		108,338,402	101,453,001	180,628,852
Depreciation and amortization expense		97,663,587us-gaap_DepreciationAndAmortization	94,889,139us-gaap_DepreciationAndAmortization	90,530,952us-gaap_DepreciationAndAmortization
Elimination Of Intercompany Receivable [Member]
Segment Reporting Information By Segment [Line Items]
Total assets		(2,770,000)	(2,392,000)	(2,267,000)
Grocery Sales [Member]
Segment Reporting Information By Segment [Line Items]
Total revenues from unaffiliated customers		3,683,353,000	3,599,820,000	3,577,510,000
Total income from operations		112,030,000	114,380,000	111,540,000
Total assets		1,515,055,000	1,528,483,000	1,486,109,000
Total capital expenditures		105,808,000	99,995,000	175,835,000
Depreciation and amortization expense		90,025,000	87,331,000	82,584,000
Other Segment [Member]
Segment Reporting Information By Segment [Line Items]
Total revenues from unaffiliated customers		152,633,000	138,720,000	140,805,000
Total income from operations		11,315,000	11,194,000	12,307,000
Total assets		144,667,000	143,237,000	158,267,000
Total capital expenditures		2,531,000	1,458,000	4,794,000
Depreciation and amortization expense		$ 7,639,000	$ 7,558,000	$ 7,947,000

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