STOCK-BASED COMPENSATION - The 2019 Zyla Plan Narrative (Details) $ / shares in Units, $ in Millions		12 Months Ended
May 20, 2020 USD ($) $ / shares shares	Dec. 31, 2021 shares
Zyla Life Sciences
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Merger exchange ratio	2.5
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years
The 2019 Zyla Plan \| Zyla Life Sciences
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issued (in shares)	1,300,000
Issued, average fair market value, per share (in dollars per share) \| $ / shares	$ 2.48
Issued, value recognized as merger consideration \| $	$ 0.4
The 2019 Zyla Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under plan (in shares)		1,246,469
Shares available for future issuance (in shares)		0
The 2019 Zyla Plan \| Stock Options \| Zyla Life Sciences
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of awards (may not exceed)	10 years
Vesting period	3 years
Vesting percentage	33.00%
The 2019 Zyla Plan \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of units awarded (in shares)		0

Business Combination, Common Stock Conversion, Common Share Exchange Ratio

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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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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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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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