Net Loss per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Sep. 02, 2017	Aug. 27, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net loss attributable to Cal-Maine Foods, Inc.	$ (15,993)	$ (30,936)
Basic weighted-average common shares (in shares)	48,330,000	48,249,000
Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract]
Restricted shares (in shares)	0	0
Dilutive potential common shares (in shares)	48,330,000	48,249,000
Earnings Per Share, Basic and Diluted [Abstract]
Basic (in dollars per share)	$ (0.33)	$ (0.64)
Diluted (in dollars per share)	$ (0.33)	$ (0.64)
Restricted Shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from calculation of earnings per share	112,353	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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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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