Business Acquisitions Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Millions		6 Months Ended
	Dec. 08, 2017	Sep. 08, 2018	Feb. 24, 2018
Business Acquisition [Line Items]
Goodwill		$ 775	$ 780
Associated Grocers Of Florida, Inc. [Member]
Business Acquisition [Line Items]
Cash and cash equivalents	$ 1	1
Accounts receivable	49	49
Inventories	48	48
Other current assets	4	4
Property, plant and equipment	84	94
Goodwill	44	39
Intangible assets	52	48
Deferred tax assets	(28)	(29)
Other assets	4	4
Accounts payable	(53)	(53)
Other current liabilities	(13)	(13)
Long-term debt and capital lease obligations	(60)	(60)
Other liabilities assumed	(1)	(1)
Total fair value of net assets acquired	131	131
Assumed obligations to make patronage payments to member-owners	5	5
Less cash acquired	(1)	(1)
Total consideration for acquisition, less cash acquired	$ 135	$ 135