Common Stock, Securities Offerings, Value, Reserved for Future Issuance

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Share-based Payments by Share-based Payment Awards, Ultimate Expense Range, Percent of Target

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Aggregate number of common shares reserved for future issuance.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Number of shares that have been repurchased and retired during the period.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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SHAREHOLDERS' EQUITY - (Narrative) (Details) - USD ($)	12 Months Ended
SHAREHOLDERS' EQUITY - (Narrative) (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Mar. 31, 2020	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining authorized repurchase amount						$ 800,000
Repurchases of common stock	$ 10,000,000	$ 3,867,000	$ 5,061,000
Average cost per share (in dollars per share)	$ 12.50	$ 16.27
Stock repurchased (in shares)	800,235
Stock repurchased, amount	$ 10,000,000.0
Value reserved for future issuance					$ 150,000,000.0
Capital shares reserved for future issuance (in shares)					800,000
Award requisite service period	1 year
Vesting period	5 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized share-based compensation expense not yet recognized	$ 3,400,000
Unamortized share-based compensation remaining weighted average vesting period	1 year 11 months 15 days
Granted (in shares)	210,272	140,156	133,060
Minimum \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ultimate expense range, percent of target	0.00%
Vesting period	3 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount authorized to repurchase common stock	$ 20,000,000	$ 10,000,000	$ 10,000,000.0	$ 10,000,000.0			$ 10,000,000.0
Maximum \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ultimate expense range, percent of target	250.00%