EARNINGS PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Earnings per share
Net income	$ 11,988	$ 8,104	$ 22,347	$ 30,606
Average number of common shares issued	26,525	26,525	26,525	26,525
Less: average number of treasury shares	1,360	1,519	1,400	1,403
Less: average number of unvested stock award shares	418	258	404	287
Average number of basic common shares outstanding	24,747	24,748	24,721	24,835
Average number of diluted common shares outstanding	24,861	24,873	24,835	25,001
Earnings per share:
Basic (in dollars per share)	$ 0.48	$ 0.33	$ 0.90	$ 1.23
Diluted (in dollars per share)	$ 0.48	$ 0.33	$ 0.90	$ 1.22
Non-vested Stock Awards
Earnings per share
Plus: dilutive effect of share-based payment arrangements (in shares)	68	46	59	60
Stock Options
Earnings per share
Plus: dilutive effect of share-based payment arrangements (in shares)	46	79	55	106

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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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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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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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