Stock-Based Compensation (Schedule Of Stock Option Plans Activity) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Options outstanding at beginning of year	1,371
Options granted	76
Options exercised	(82)
Options forfeited and expired	60
Options outstanding at end of year	1,305
Options exercisable at end of year	1,106
Options granted during the year, price per share	$ 57.34
Options exercised during the year, price per share	$ 46.15
Options outstanding at the end of year, price per share	$ 72.08	$ 71.48
Options exercisable at end of year, price per share	$ 74.89
Stock Options Plans [Member]
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Options outstanding at beginning of year	1,371	1,481	1,506
Options granted	76	40	76
Options exercised	(82)	(74)	(35)
Options forfeited and expired	(60)	(76)	(66)
Options outstanding at end of year	1,305	1,371	1,481
Options exercisable at end of year	1,106	1,160	1,165
Options granted during the year, price per share	$ 57.34	$ 46.80	$ 28.37
Minimum [Member]
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Options exercised during the year, price per share	$ 28.37	$ 16.66	$ 16.66
Options forfeited and expired during the year, price per share	$ 28.37	$ 22.63	$ 19.94
Options outstanding at the end of year, price per share	$ 28.37	$ 28.37	$ 16.66
Options exercisable at end of year, price per share	$ 28.37	$ 28.37	$ 16.66
Maximum [Member]
Share Based Compensation Arrangement by Share Based Payment Award [Line Items]
Options exercised during the year, price per share	$ 63.14	$ 57.88	$ 48.50
Options forfeited and expired during the year, price per share	$ 93.65	$ 93.65	$ 93.65
Options outstanding at the end of year, price per share	$ 93.65	$ 93.65	$ 93.65
Options exercisable at end of year, price per share	$ 93.65	$ 93.65	$ 93.65