Quarterly report pursuant to Section 13 or 15(d)

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

v3.5.0.2
Stock-Based Compensation (Schedule Of Weighted Average Assumptions For Restricted Stock Units) (Details) - Restricted Stock Units [Member] - $ / shares
3 Months Ended 6 Months Ended
Jun. 30, 2016
Jun. 30, 2015
Jun. 30, 2016
Jun. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Vesting period, years 2 years 9 months 18 days 2 years 7 months 24 days 3 years 9 months 28 days 3 years 9 months 25 days
Expected annual dividend yield 1.20% 1.05% 1.16% 1.14%
Estimated average grant date fair value per restricted stock unit (in dollars per share) $ 54.80 $ 55.80 $ 55.94 $ 51.01