EARNINGS PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Earnings per share
Net income (loss)	$ 8,759	$ (1,106)
Average number of common shares issued	26,525	26,525
Less: average number of treasury shares	1,295	1,425
Less: average number of unvested stock award shares	427	402
Average number of basic common shares outstanding	24,803	24,698
Average number of diluted common shares outstanding	24,955	24,698
Earnings per share:
Total basic earning per share (in dollars per share)	$ 0.35us-gaap_EarningsPerShareBasic	$ (0.04)us-gaap_EarningsPerShareBasic
Total diluted earnings per share (in dollars per share)	$ 0.35us-gaap_EarningsPerShareDiluted	$ (0.04)us-gaap_EarningsPerShareDiluted
Unvested Stock Award shares
Earnings per share
Plus: dilutive effect of share-based payment arrangements (in shares)	89
Options
Earnings per share
Plus: dilutive effect of share-based payment arrangements (in shares)	63

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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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