Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Schedule Of Weighted Average Assumptions) (Details)

v3.10.0.1
Stock-Based Compensation (Schedule Of Weighted Average Assumptions) (Details) - Stock Option [Member] - $ / shares
3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Expected term, years 4 years 3 months 20 days 4 years 4 months 6 days 4 years 5 months 28 days 4 years 6 months 16 days
Expected stock price volatility 27.75% 28.79% 28.41% 28.91%
Risk-free interest rate 2.81% 1.68% 2.47% 1.72%
Expected annual dividend yield 1.01% 1.23% 1.15% 1.30%
Weighted average grant date fair value (in dollars per share) $ 21.37 $ 13.47 $ 18.80 $ 13.03