Acquisitions (Details) - KUPI $ / shares in Units, $ in Thousands	12 Months Ended
Jun. 30, 2016 USD ($) $ / shares
Unaudited Pro Forma Financial Results
Total net Sales	$ 689,754
Net income attributable to Lannett Company, Inc.	$ 61,916
Earnings per common share attributable to Lannett Company, Inc.:
Basic (in dollars per share) \| $ / shares	$ 1.70
Diluted (in dollars per share) \| $ / shares	$ 1.66
Acquisition-related expenses	$ 28,900
Acquisition costs incurred by acquirer
Earnings per common share attributable to Lannett Company, Inc.:
Acquisition-related expenses	21,500
Acquisition costs incurred by acquiree
Earnings per common share attributable to Lannett Company, Inc.:
Acquisition-related expenses	7,400
Fair value set-up adjustment
Earnings per common share attributable to Lannett Company, Inc.:
Inventory fair value step-up adjustments	$ 17,000

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Amount of addition (reduction) to the amount at which an asset could be incurred (settled) in a current transaction between willing parties.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
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