Stock-Based Compensation (Schedule Of Non-Vested Restricted Stock Units and Performance Stock Units) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Restricted Stock Units (RSUs)
Number of Shares
Number of Shares, Non-vested, beginning balance	676,299
Number of Shares, Granted	201,094
Number of Shares, Vested	(168,021)
Number of Shares, Forfeited	(18,958)
Number of Shares, Non-vested, ending balance	690,414	676,299
Weighted Average Grant Date Fair Value
Weighted Average Fair Value, Non-vested, beginning balance (in dollars per share)	$ 77.73
Weighted Average Fair Value, Granted (in dollars per share)	107.75
Weighted Average Fair Value, Vested (in dollars per share)	79.76
Weighted Average Fair Value, Forfeited (in dollars per share)	85.63
Weighted Average Fair Value, Non-vested, ending balance (in dollars per share)	$ 85.77	$ 77.73
Performance Stock Units
Number of Shares
Number of Shares, Non-vested, beginning balance	256,394
Number of Shares, Granted	69,491
Number of Shares, Vested	(71,757)
Number of Shares, Forfeited	(3,759)
Number of Shares, Non-vested, ending balance	250,369	256,394
Weighted Average Grant Date Fair Value
Weighted Average Fair Value, Non-vested, beginning balance (in dollars per share)	$ 97.14
Weighted Average Fair Value, Granted (in dollars per share)	147.98	$ 109.94	$ 74.61
Weighted Average Fair Value, Vested (in dollars per share)	114.38
Weighted Average Fair Value, Forfeited (in dollars per share)	109.38
Weighted Average Fair Value, Non-vested, ending balance (in dollars per share)	$ 106.13	$ 97.14