Stock-Based Compensation Plans (Schedule Of Valuation Assumptions) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Stock-Based Compensation Plans [Abstract]
Stock price on date of issuance	$ 509.46	$ 462.04	$ 445.35
Grant date fair value per share	$ 111.24	$ 104.69	$ 96.91
Number of options granted	315,555	312,598	326,806
Expected term (years)	3 years 6 months	3 years 6 months	3 years 6 months
Risk free rate of return	4.99%	4.39%	0.87%
Volatility	19.24%	22.29%	28.81%
Dividend yield	0.30%	0.30%	0.30%
Forfeiture rate