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Business Combination, Consideration Transferred, Equity Interests Issued And Issuable, Entity Shares Issued Per Acquiree Share

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Business Combination, Pro Forma Information, Earnings Or Loss Of Acquiree, Excluded

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Class Of Warrant Or Right, Exercise Cap, Aggregate Ownership Percentage

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Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Issued In Connection With Acquisition

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Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Issued In Connection With Acquisition, Average Fair Market Value

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Issued In Connection With Acquisition, Value Recognized As Merger Consideration

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Warrant, Exercise Period

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- Definition

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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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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ACQUISITIONS - Narrative (Details) $ / shares in Units, $ in Millions		3 Months Ended	6 Months Ended
	May 20, 2020 USD ($) $ / shares shares	Jun. 30, 2020 USD ($)	Jun. 30, 2020 USD ($) segment	Jun. 30, 2019 USD ($)
Business Acquisition [Line Items]
Number of operating segments \| segment			1
Zyla Life Sciences
Business Acquisition [Line Items]
Number of shares of Assertio common stock for each share of Zyla common stock (in shares) \| shares	2.5
Business transaction costs associated with merger		$ 4.2	$ 6.6
Proforma information adjustment, excluded income from Zyla's January 2019 Reorganization				$ 115.2
Zyla Life Sciences \| Iroko \| Warrant Agreements
Business Acquisition [Line Items]
Warrant, exercise price per share (in dollars per share) \| $ / shares	$ 0.0001
Warrant exercise cap, aggregate ownership percentage	49.00%
Warrant, exercise period	18 months
Zyla Life Sciences \| 2019 Plan
Business Acquisition [Line Items]
Issued (in shares) \| shares	5,000,000.0
Issued, average fair market value, per share (in dollars per share) \| $ / shares	$ 0.62
Issued, value recognized as merger consideration	$ 0.4
Zyla Life Sciences \| Stock options, awards and equivalents \| 2019 Plan
Business Acquisition [Line Items]
Merger exchange ratio	2.5
Vesting period	3 years
Zyla Life Sciences \| Stock options, awards and equivalents \| 2019 Plan \| Maximum
Business Acquisition [Line Items]
Term of award (may not exceed)	10 years
Zyla Life Sciences \| Stock options, awards and equivalents \| 2019 Plan \| Minimum
Business Acquisition [Line Items]
Awards vesting by the end of the first year	33.00%