Earnings (Loss) Per Share Attributable to the Stockholders of Argan (Details) (USD $)	3 Months Ended
Apr. 30, 2013	Apr. 30, 2012
Earnings (Loss) Per Share Attributable to the Stockholders of Argan, Inc (Textual) [Abstract]
Additional shares included in the calculation of diluted EPS	151,000
Additional shares included in the calculation of diluted EPS		282,000
Shares covered by antidilutive stock options	240,000	388,000
Income (Loss) from Continuing Operations Attributable to Parent	$ 6,410,000	$ 4,723,000

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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+ Details

- Definition

Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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+ Details

- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of call options and warrants using the treasury stock method.

+ References

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+ Details