Net Income (Loss) per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Feb. 29, 2020	Mar. 02, 2019	Feb. 29, 2020	Mar. 02, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income (loss) attributable to Cal-Maine Foods, Inc.	$ 13,749	$ 39,777	$ (42,072)	$ 73,989
Basic weighted-average common shares (in shares)	48,473,000	48,417,000	48,455,000	48,416,000
Dilutive potential common shares (in shares)	48,588,000	48,533,000	48,455,000	48,545,000
Antidilutive securities excluded from computation of earnings per share (in shares)	0	0	121,000	0
Net income (loss) per common share attributable to Cal-Maine Foods, Inc.:
Basic (in dollars per share)	$ 0.28	$ 0.82	$ (0.87)	$ 1.53
Diluted (in dollars per share)	$ 0.28	$ 0.82	$ (0.87)	$ 1.52
Restricted Shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Effect of dilutive securities (in shares)	115,000	116,000	0	129,000

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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