ACQUISITIONS - Acquisition Date Fair Value of Consideration Transferred (Details) $ / shares in Units, $ in Thousands	May 20, 2020 USD ($) $ / shares shares
Business Acquisition [Line Items]
Share price (in dollars per share) \| $ / shares	$ 0.90
Zyla Life Sciences
Business Acquisition [Line Items]
Total number of Company ordinary shares issued (in shares) \| shares	25,478,539
Assertio share price as of May 20, 2020 (in dollars per share) \| $ / shares	$ 0.90
Taxes paid by the Company on behalf of Zyla (in thousands)	$ 529
Total purchase consideration (in thousands)	35,086
Zyla Life Sciences \| Common Stock
Business Acquisition [Line Items]
Fair value issued (in thousands)	22,931
Zyla Life Sciences \| Warrants and Options
Business Acquisition [Line Items]
Fair value issued (in thousands)	$ 11,626
Zyla Life Sciences \| Warrants
Business Acquisition [Line Items]
Purchase price, number of shares outstanding (in shares) \| shares	12,430,913
Zyla Life Sciences \| Warrants \| Zyla Life Sciences
Business Acquisition [Line Items]
Purchase price, number of shares outstanding (in shares) \| shares	4,972,365
Purchase price, number of shares outstanding, per share (in dollars per share) \| $ / shares	$ 0.0004

Business Acquisition, Equity Interest Issued Or Issuable, Shares Outstanding, Exercise Price

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- Definition

Business Acquisition, Equity Interest Issued Or Issuable, Shares Outstanding, Number Of Shares

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- Definition

Business Combination, Consideration Transferred, Equity Interests Issued and Issuable, Taxes Paid

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Number of shares of equity interests issued or issuable to acquire entity.

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-Publisher FASB
-Name Accounting Standards Codification
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Price of a single share of a number of saleable stocks of a company.

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