Earnings Per Common Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014
Earnings Per Common Share
Net Income Attributable to Lannett Company, Inc	$ 36,233	$ 22,995	$ 115,976	$ 33,566
Basic weighted average common shares outstanding	35,880,954	35,025,968	35,715,061	33,082,460
Effect of potentially dilutive stock options and restricted stock awards	1,329,184	1,743,625	1,367,077	1,503,547
Diluted weighted average common shares outstanding	37,210,138	36,769,593	37,082,138	34,586,007
Earnings per common share attributable to Lannett Company, Inc.:
Basic (in dollars per share)	$ 1.01us-gaap_EarningsPerShareBasic	$ 0.66us-gaap_EarningsPerShareBasic	$ 3.25us-gaap_EarningsPerShareBasic	$ 1.01us-gaap_EarningsPerShareBasic
Diluted (in dollars per share)	$ 0.97us-gaap_EarningsPerShareDiluted	$ 0.63us-gaap_EarningsPerShareDiluted	$ 3.13us-gaap_EarningsPerShareDiluted	$ 0.97us-gaap_EarningsPerShareDiluted
Anti-dilutive shares excluded in the computation of diluted earnings per share	77,000	3,000	490,000	9,000

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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