STOCK-BASED COMPENSATION PLANS (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended		12 Months Ended			12 Months Ended			12 Months Ended			12 Months Ended
	Dec. 31, 2011 plan	Jun. 08, 2011	Dec. 31, 2011 Long-Term Incentive Plan Options	Dec. 31, 2010 Long-Term Incentive Plan Options Y	Dec. 31, 2009 Long-Term Incentive Plan Options Y	Dec. 31, 2011 Equity Incentive Plan	Dec. 31, 2010 Equity Incentive Plan	Apr. 27, 2005 Equity Incentive Plan	Dec. 31, 2011 Equity Incentive Plan Restricted Stock Awards (RSAs)	Dec. 31, 2010 Equity Incentive Plan Restricted Stock Awards (RSAs)	Dec. 31, 2011 Equity Incentive Plan Restricted Stock Awards (RSAs) Outside directors	Dec. 31, 2011 Equity Incentive Plan Restricted Stock Awards (RSAs) Restricted stock awards to employees	Dec. 31, 2011 Equity Incentive Plan Stock Appreciation Rights (SARs)	Dec. 31, 2009 Equity Incentive Plan Stock Appreciation Rights (SARs) Y
STOCK-BASED COMPENSATION PLANS
Number of stockholder-approved stock-based compensation plans	2
Stock-based Compensation
Options vested on anniversary date (as a percent)			25.00%
Vesting period	12 months		4 years									48 months	48 months
Expiration period of award (in years)			P10Y										P10Y
Summary of the awards made under the Long-Term Incentive Plan
Outstanding at the beginning of the period (in shares)			65,000	125,500
Exercised (in shares)			(65,000)	(60,500)
Outstanding at the end of the period (in shares)				65,000
Weighted Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)			$ 12.58	$ 12.75
Exercised (in dollars per share)			$ 12.58	$ 12.94
Outstanding at the end of the period (in dollars per share)				$ 12.58
Weighted Average Remaining Contractual Life
Weighted average remaining contractual life (in years)				1.01	1.6
Options Exercisable
Options exercisable at the beginning of the period (in shares)			65,000	125,500
Exercised (in shares)			(65,000)	(60,500)
Options exercisable at the end of the period (in shares)				65,000
Shares authorized to be issued under the plan (in shares)	2,000,000	2,000,000						2,000,000
Awards granted (in shares)									85,426	77,956
Awards cancelled (in shares)										2,754
Weighted average grant date fair value (in dollars per share)									$ 17.44	$ 17.74
Percentage of RSAs granted to outside directors expected to vest											100.00%
Assumptions utilized to determine the grant-date fair value
Expected dividend yield (as a percent)														3.07%
Expected volatility (as a percent)														22.10%
Risk-free interest rate (as a percent)														2.84%
Expected holding period (in years)														6.75
SARs outstanding and RSAs
Stock Appreciation Rights (SAR) outstanding													361,356
Exercisable (in shares)													310,768
Weighted average fair value of shares exercisable (in dollars per share)													$ 3.70
Compensation expense
Recorded compensation costs for the RSAs and SARs						$ 1,300	$ 1,077
Unrecognized future compensation expense for the RSAs and SARs						$ 1,719