Net Loss per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Dec. 01, 2018	Dec. 02, 2017	Dec. 01, 2018	Dec. 02, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income (loss) attributable to Cal-Maine Foods, Inc.	$ 21,807	$ (26,136)	$ 34,212	$ (42,129)
Basic weighted-average common shares (in shares)	48,391	48,330	48,390	48,330
Weighted Average Number Diluted Shares Outstanding Adjustment	143	0	135	0
Dilutive potential common shares (in shares)	48,534	48,330	48,525	48,330
Earnings Per Share, Basic and Diluted [Abstract]
Basic (in dollars per share)	$ 0.45	$ (0.54)	$ 0.71	$ (0.87)
Diluted (in dollars per share)	$ 0.45	$ (0.54)	$ 0.71	$ (0.87)
Restricted Shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from calculation of earnings per share	0	138	0	127

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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