Net Income Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Nov. 26, 2016	Nov. 28, 2015	Nov. 26, 2016	Nov. 28, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income (loss) attributable to Cal-Maine Foods, Inc.	$ (23,010)	$ 109,230	$ (53,946)	$ 252,253
Basic weighted-average common shares (in shares)	48,250,000	48,164,000	48,249,000	48,164,000
Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract]
Restricted shares (in shares)	0	197,000	0	190,000
Dilutive potential common shares (in shares)	48,250,000	48,361,000	48,249,000	48,354,000
Earnings Per Share, Basic and Diluted [Abstract]
Basic (in dollars per share)	$ (0.48)	$ 2.27	$ (1.12)	$ 5.24
Diluted (in dollars per share)	$ (0.48)	$ 2.26	$ (1.12)	$ 5.22
Restricted Shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from calculation of earnings per share	155,285		147,753

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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