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SHARE-BASED COMPENSATION - Assumptions Used in Valuing Options Granted (Detail)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Expected term (years)	6 years 6 months	6 years 10 months 24 days	6 years 10 months 24 days
Expected volatility	38.00%	30.00%	36.00%
Annual forfeiture rate	1.60%	1.60%	1.80%
Risk-free interest rate	2.10%	3.40%	3.10%
Dividend yield	1.30%	1.30%	1.30%

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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