Net Income Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Aug. 27, 2016	Aug. 29, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income (loss) attributable to Cal-Maine Foods, Inc.	$ (30,936)	$ 143,023
Basic weighted-average common shares	48,249	48,163
Restricted shares		335
Dilutive potential common shares	48,249	48,498
Basic	$ (0.64)	$ 2.97
Diluted	$ (0.64)	$ 2.95
Restricted Shares [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from calculation of earnings per share	140,551

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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