Earnings (Loss) Per Common Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Sep. 30, 2013	Sep. 30, 2012
Earnings (Loss) Per Common Share
Net Income (Loss) Attributable to Lannett Company, Inc	$ (5,995)	$ 2,926
Basic weighted average common shares outstanding	29,586,237	28,278,514
Effect of potentially dilutive options and restricted stock awards (in shares)		190,710
Diluted weighted average common shares outstanding	29,586,237	28,469,224
Earnings (Loss) per common share attributable to the entity:
Basic (in dollars per share)	$ (0.20)	$ 0.10
Diluted (in dollars per share)	$ (0.20)	$ 0.10
Anti-dilutive shares excluded in the computation of diluted earnings per share	3,000,000	2,000,000

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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- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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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 average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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