STOCK-BASED COMPENSATION - Restricted Stock Activity (Details) - $ / shares	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Service-based Awards
Number of Shares
Outstanding (in shares)	41,398
Shares granted (in shares)	460,382	174,720	105,035
Shares forfeited (in shares)	(271)
Shares vested (in shares)	(232,907)
Outstanding (in shares)	268,602	41,398
Weighted- Average Price
Beginning of the Year (in dollars per share)	$ 24.10
Shares granted (in dollars per share)	9.15	$ 21.40	$ 26.70
Shares forfeited (in dollars per share)	24.50
Shares vested (in dollars per share)	10.32
End of the Year (in dollars per share)	$ 10.44	$ 24.10
Service and Performance-based Awards
Number of Shares
Outstanding (in shares)	37,500
Shares granted (in shares)	0
Shares forfeited (in shares)	0
Shares vested (in shares)	(21,250)
Outstanding (in shares)	16,250	37,500
Weighted- Average Price
Beginning of the Year (in dollars per share)	$ 27.00
Shares granted (in dollars per share)	0
Shares forfeited (in dollars per share)	0
Shares vested (in dollars per share)	27.00
End of the Year (in dollars per share)	$ 27.00	$ 27.00
Service and Market-based Awards
Number of Shares
Outstanding (in shares)	118,962
Shares granted (in shares)	0
Shares forfeited (in shares)	(106,800)
Shares vested (in shares)	(6,917)
Outstanding (in shares)	5,245	118,962
Weighted- Average Price
Beginning of the Year (in dollars per share)	$ 18.00
Shares granted (in dollars per share)	0
Shares forfeited (in dollars per share)	18.20
Shares vested (in dollars per share)	16.70
End of the Year (in dollars per share)	$ 16.70	$ 18.00
Service, Performance, and Market-based Awards
Number of Shares
Outstanding (in shares)	70,800
Shares granted (in shares)	0
Shares forfeited (in shares)	0
Shares vested (in shares)	(31,600)
Outstanding (in shares)	39,200	70,800
Weighted- Average Price
Beginning of the Year (in dollars per share)	$ 9.80
Shares granted (in dollars per share)	0
Shares forfeited (in dollars per share)	0
Shares vested (in dollars per share)	9.80
End of the Year (in dollars per share)	$ 9.80	$ 9.80

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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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The weighted average fair value at grant date for nonvested equity-based awards issued 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 non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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