Accrued Dividends Payable And Dividends per Common Share (Schedule of Dividends) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Feb. 29, 2020	Mar. 02, 2019	Feb. 29, 2020	Mar. 02, 2019	Jun. 01, 2019
Class of Stock [Line Items]
Net income (loss) attributable to Cal-Maine Foods, Inc. available for dividend	$ 13,749	$ 39,777	$ (42,072)	$ 73,989
One third of net income attributable to parent	$ 0	$ 13,245	$ 0	$ 24,626
Common stock, shares outstanding (in shares)	48,774	48,695	48,774	48,695
Dividends per common share (in dollars per share)	$ 0	$ 0.272	$ 0	$ 0.506
Common Stock
Class of Stock [Line Items]
Common stock, shares outstanding (in shares)	43,974	43,895	43,974	43,895
Class A Common Stock
Class of Stock [Line Items]
Common stock, shares outstanding (in shares)	4,800	4,800	4,800	4,800	4,800

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