XML 50 R39.htm IDEA: XBRL DOCUMENT v2.3.0.15
Equity Compensation Plans (Principal Assumptions For SSARs Granted Fair Value) (Details) (USD $)
9 Months Ended
Sep. 30, 2011
Sep. 30, 2010
Equity Compensation Plans [Abstract]  
Weighted average fair value of SSARs granted during the period$ 11.47$ 10.41
Risk-free interest rate1.70%2.20%
Expected volatility23.20%29.80%
Expected dividend yield2.10%2.20%
Expected life, in years55
Termination rate0.99%1.09%
Exercise multiple1.431.38