EARNINGS PER SHARE (Computation of Basic and Diluted Earnings Per Share) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Jun. 30, 2013		Jun. 30, 2012
Earnings Per Share [Abstract]
Net income	$ 6,331		$ 6,412		$ 11,993		$ 12,995
Dividends and undistributed earnings allocated to participating securities	(20)	[1]	(18)	[1]	(30)	[1]	(30)	[1]
Net income loss available to common shareholders	$ 6,311		$ 6,394		$ 11,963		$ 12,965
Weighted-average common shares outstanding for basic EPS	7,637,433		7,675,819		7,632,586		7,673,927
Dilutive effect of stock-based awards	14,766	[2]	11,801	[2]	14,156	[2]	12,820	[2]
Weighted-average common and potential common shares for diluted EPS	7,652,199		7,687,620		7,646,742		7,686,747
Basic EPS	$ 0.83		$ 0.84		$ 1.57		$ 1.69
Diluted EPS	$ 0.82		$ 0.83		$ 1.56		$ 1.69

[1] Represents dividends paid and undistributed earnings allocated to nonvested restricted stock awards.

[2] Represents the effect of the assumed exercise of stock options, vesting of restricted shares, and vesting of restricted stock units, based on the treasury stock method.