EARNINGS PER SHARE (EPS) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
EARNINGS PER SHARE (EPS) [Abstract]
Net income	$ 10,631	$ 11,795	$ 33,240	$ 33,573
Less: Dividends paid on earnings allocated to participating securities	(44)	(46)	(135)	(137)
Income attributable to common stock	10,587	11,749	33,105	33,436
Weighted Average Number Of Shares Outstanding Including Participating Securities Basic (in shares)	35,664,100	34,736,804	35,371,184	34,539,530
Less: weighted average participating securities (in shares)	(318,314)	(328,003)	(321,325)	(327,099)
Weighted average shares outstanding utilized in the calculation of basic EPS (in shares)	35,345,786	34,408,801	35,049,859	34,212,431
Earnings Per Share, Basic (in dollars per share)	$ 0.30	$ 0.34	$ 0.95	$ 0.98
Income attributable to common stock	$ 10,587	$ 11,749	$ 33,105	$ 33,436
Weighted average common shares outstanding	35,345,786	34,408,801	35,049,859	34,212,431
Common stock equivalents resulting from the dilutive effect of "in-the-money" stock options	181,717	89,016	107,788	75,348
Weighted average shares outstanding utilized in the calculation of diluted EPS (in shares)	35,527,503	34,497,817	35,157,647	34,287,779
Earnings Per Share, Diluted (in dollars per share)	$ 0.30	$ 0.34	$ 0.95	$ 0.98
Weighted average shares excluded from earnings per share calculation (in shares)	761,193	1,330,792	919,821	1,323,076