STOCK-BASED AWARDS - Additional Information (Details) - $ / shares	9 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Weighted Average Grant Date Fair Value
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	46,610,000	46,331,000
Restricted Stock Awards
Units
Outstanding-beginning of year (in shares)	639,000
Granted at fair value (in shares)	297,000
Vested (in shares)	(279,000)
Forfeited (in shares)	(64,000)
Outstanding-end of period (in shares)	593,000
Weighted Average Grant Date Fair Value
Outstanding-beginning of year (in dollars per share)	$ 17.98
Granted at fair value (in dollars per share)	87.92
Vested (in dollars per share)	24.87
Forfeited (in dollars per share)	51.16
Outstanding-end of period (in dollars per share)	$ 46.21
Restricted Stock Awards \| First year
Stock-Based Awards
Annual award vesting percentage	33.30%
Restricted Stock Awards \| Second year
Stock-Based Awards
Annual award vesting percentage	33.30%
Restricted Stock Awards \| Third year
Stock-Based Awards
Annual award vesting percentage	33.40%

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Percentage

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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

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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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- 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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