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Represents the number of grants that will be made if target goal are not achieved.

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Number of Tranches.

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Represents the percentage of performance target for grant of performance stock unit award.

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Value 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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The number of equity-based payment instruments, excluding stock (or unit) options, that kept as vesting level due to COVID-19.

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Represents the fair value of restricted stock units granted during the period.

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Aggregate grant date fair value of equity instruments other than options.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

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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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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 of a company.

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

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Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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STOCKHOLDERS' EQUITY - Awards granted (Details) $ / shares in Units, $ in Millions		3 Months Ended		9 Months Ended
	Aug. 19, 2022 shares	Sep. 30, 2022 USD ($) tranche shares	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($) tranche shares	Sep. 30, 2021 USD ($)	May 07, 2022 $ / shares	May 03, 2022 $ / shares	Feb. 16, 2022 $ / shares
STOCKHOLDERS' EQUITY
Stock-based compensation expense \| $		$ (3.6)	$ 5.0	$ 22.3	$ 18.8
Conversion of share based payment awards into preferred stock				1
Conversion ratio of share based payment awards into common stock				1
Cumulative Adjusted EBITDA Target
STOCKHOLDERS' EQUITY
Percentage of performance targets and vesting level				50.00%
Cumulative Adjusted Free Cash Flow Target
STOCKHOLDERS' EQUITY
Percentage of performance targets and vesting level				75.00%
Board of Directors
STOCKHOLDERS' EQUITY
Stock-based compensation expense \| $				$ 0.8	0.9
2022 Performance share award
STOCKHOLDERS' EQUITY
Granted (in shares)				464,540
Stock value \| $		4.5		$ 4.5
2021 Performance share award
STOCKHOLDERS' EQUITY
Granted (in shares)				1,757,080
Stock value \| $		17.3		$ 17.3
Percentage of performance target				100.00%
2020 Performance share award
STOCKHOLDERS' EQUITY
Granted (in shares)				859,366
Stock value \| $		8.5		$ 8.5
Percentage of performance target				100.00%
Restricted stock unit
STOCKHOLDERS' EQUITY
Stock-based compensation expense \| $		$ 3.5	3.4	$ 9.8	9.1
Restricted stock unit \| Members of management and executive officers
STOCKHOLDERS' EQUITY
Number of shares to be received for each unit		1		1
Performance Vesting \| Members of management and executive officers
STOCKHOLDERS' EQUITY
Granted (in shares)				1,394,270
Number of tranches \| tranche		3		3
Awards to be granted if target not achieved (in shares)				0
Performance Vesting \| Members of management and executive officers \| Minimum
STOCKHOLDERS' EQUITY
PSUs vesting as a percentage of performance target				80.00%
Percentage of performance target				50.00%
Performance Vesting \| Members of management and executive officers \| Maximum
STOCKHOLDERS' EQUITY
PSUs vesting as a percentage of performance target				120.00%
Percentage of performance target				200.00%
Performance stock unit expense
STOCKHOLDERS' EQUITY
Stock-based compensation expense \| $		$ (7.1)		$ 11.7	4.2
Special Performance Stock
STOCKHOLDERS' EQUITY
Stock-based compensation expense \| $			$ 1.6		$ 4.6
Special Performance Stock \| 2021 Special PSU \| Minimum
STOCKHOLDERS' EQUITY
PSUs vesting as a percentage of performance target				80.00%
Special Performance Stock \| 2021 Special PSU \| Maximum
STOCKHOLDERS' EQUITY
PSUs vesting as a percentage of performance target				120.00%
2013 Equity Incentive Plan \| Members of management
STOCKHOLDERS' EQUITY
Granted (in shares)				1,394,270
Grant date fair value (in dollars) \| $				$ 13.6
Vesting period (in years)				3 years
Vesting rights percentage				33.33%
2013 Equity Incentive Plan \| Stock options \| Board of Directors
STOCKHOLDERS' EQUITY
Shares granted				41,650
Grant date fair value \| $				$ 0.8
2013 Equity Incentive Plan \| RSU and PSU Units
STOCKHOLDERS' EQUITY
Price per share (in dollars per share) \| $ / shares						$ 7.61	$ 7.76	$ 9.84
2013 Equity Incentive Plan \| Restricted stock unit \| Members of management
STOCKHOLDERS' EQUITY
Number of days for settlement				30 days
2013 Equity Incentive Plan \| Performance Vesting \| Members of management and executive officers
STOCKHOLDERS' EQUITY
Percentage of performance target				100.00%
Awards to be granted upon achieving 100% of performance target (in shares)				1,394,270
2013 Equity Incentive Plan \| Performance stock unit expense
STOCKHOLDERS' EQUITY
Percentage of performance target	100.00%
Awards to be granted upon achieving 100% of performance target (in shares)	5,124,782
AMC Preferred Equity Units \| 2013 Equity Incentive Plan \| Board of Directors
STOCKHOLDERS' EQUITY
Shares granted				41,650