EARNINGS PER SHARE (Calculations of Basic and Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Aug. 31, 2026	Aug. 31, 2025	Aug. 31, 2024
Earnings Per Share [Abstract]
Net earnings	$ 655,849	$ 84,662	$ 485,491
Earnings Per Share, Basic [Abstract]
Average basic shares outstanding (in shares)	110,857,469	112,994,381	115,844,977
Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract]
Effect of dilutive securities (in shares)	1,007,398	1,092,369	1,307,575
Average diluted shares outstanding (in shares)	111,864,867	114,086,750	117,152,552
Diluted earnings per share from continuing operations attributable to CMC (USD per share)	$ 5.86	$ 0.74	$ 4.14

The amount of net income (loss) derived from continuing operations during 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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+ Details

- Definition

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

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