INVESTMENT IN JOINT VENTURES - Variable Interest Entity (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Nov. 27, 2016	Nov. 29, 2015	Nov. 27, 2016	Nov. 29, 2015	May 29, 2016	May 31, 2015
Condensed Combined and Consolidated Balance Sheets
Cash and equivalents	$ 69.4	$ 23.9	$ 69.4	$ 23.9	$ 36.4	$ 30.6
Inventories	615.9		615.9		498.9
Prepaid expenses and other current assets	18.5		18.5		58.2
Property, plant and equipment, net	1,134.3		1,134.3		1,043.1
Goodwill	131.7		131.7		133.9
Intangible assets, net	38.3		38.3		39.6
Notes payable	25.2		25.2		24.9
Current portion of long-term debt	39.0		39.0		13.5
Accounts payable	314.3		314.3		238.0
Long-term debt, excluding current portion	2,382.0		2,382.0		104.6
Redeemable noncontrolling interest (b)	50.0		$ 50.0		47.4
Lamb Weston BSW
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)			49.99%
Purchases	12.5	11.4	$ 36.6	27.8
Condensed Combined and Consolidated Balance Sheets
Cash and equivalents	12.0		12.0		4.3
Receivables, less allowance for doubtful accounts (a)	0.1		0.1		0.1
Inventories	1.9		1.9		1.2
Prepaid expenses and other current assets	0.1		0.1		0.4
Property, plant and equipment, net	50.4		50.4		52.2
Goodwill	18.8		18.8		18.8
Intangible assets, net	4.8		4.8		5.2
Total assets	88.1		88.1		82.2
Notes payable					1.0
Current portion of long-term debt	1.2		1.2		0.5
Accounts payable	10.1		10.1		10.9
Accrued liabilities	2.5		2.5		1.7
Long-term debt, excluding current portion	28.8		28.8		29.5
Total liabilities	42.6		42.6		43.6
Redeemable noncontrolling interest (b)	50.0		50.0		$ 47.4
Lamb Weston BSW | Eliminated in consolidation
Condensed Combined and Consolidated Balance Sheets
Receivables, less allowance for doubtful accounts (a)	$ 22.2	$ 25.8	$ 22.2	$ 25.8
Lamb Weston RDO
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)			50.00%