EARNINGS PER SHARE - Computation of basic and diluted earnings per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
EARNINGS PER SHARE
Net income for common shareholders	$ 10,595	$ 10,019
Weighted-average shares (thousands)
Basic weighted-average shares outstanding	24,497	24,508
Dilutive effect of outstanding stock options and unvested restricted stock awards	108	108
Diluted weighted-average shares outstanding	24,605	24,616
Earnings per share:
Basic	$ 0.43	$ 0.41
Diluted	$ 0.43	$ 0.41

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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- Definition

Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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