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SHARE-BASED COMPENSATION - Weighted Average Assumptions Used in Estimating the Value of Performance Share Units Granted (Detail) (Performance share units, USD $)
3 Months Ended
Mar. 31, 2012
Performance share units
 
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Performance period 1/1/2012 – 12/31/2013
Valuation date closing stock price $ 20.56
Expected dividends 2.92%
Risk-free rate minimum 0.08%
Risk-free rate maximum 0.32%
Volatility minimum 34.66%
Volatility maximum 34.86%