XML 19 R48.htm IDEA: XBRL DOCUMENT

Significant Accounting Policies (Schedule of Fair Value Assumptions and Methodology) (Details)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Accounting Policies [Abstract]
Risk-free interest rate	1.44%	2.64%	3.04%
Dividend yield	1.20%	1.20%	1.20%
Volatility factors	46.70%	46.70%	44.30%
Weighted-average expected life	8 years	8 years	8 years

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.

+ References+ Details