REVENUE FROM CONTRACTS WITH CUSTOMERS - Consolidated Statements of Earnings (Details) - USD ($) $ in Millions	3 Months Ended
	Aug. 26, 2018	Aug. 27, 2017
Revenue from Contracts with Customers
Net sales	$ 914.9	$ 817.5
Cost of sales	684.3	621.2
Income from operations	152.6	137.6
Income tax expense	34.3	44.1
Net income attributable to Lamb Weston Holdings, Inc.	107.8	$ 83.4
Calculated under Revenue Guidance in Effect before Topic 606 | Accounting Standards Update 2014-09
Revenue from Contracts with Customers
Net sales	917.4
Cost of sales	685.8
Income from operations	153.6
Income tax expense	34.6
Net income attributable to Lamb Weston Holdings, Inc.	108.5
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
Revenue from Contracts with Customers
Net sales	(2.5)
Cost of sales	(1.5)
Income from operations	(1.0)
Income tax expense	(0.3)
Net income attributable to Lamb Weston Holdings, Inc.	$ (0.7)