Share-Based Compensation (Details 1)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Stock options granted under the Company's option plans
Expected term (years)	5 years 9 months 18 days	5 years 7 months 6 days	5 years 9 months 18 days	5 years 8 months 0 days
Stock volatility	36.00%	41.30%	36.10%	40.50%
Risk free interest rates	0.80%	1.10%	1.00%	1.90%
Dividends during expected terms	1.50%	1.70%	1.60%	1.40%