Stockholders' Equity (Summary Of Activity Related To Stock Option Plans) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	9 Months Ended
	Sep. 30, 2012
Stockholders' Equity Note [Abstract]
Shares Available for Grant, Beginning Balances	7,013,508
Shares Available for Grant, Granted	(1,321,197)
Shares Available for Grant, Exercised	0
Shares Available for Grant, Canceled	48
Shares Available for Grant, Expired	(1,160,721)
Shares Available for Grant, Ending Balances	4,531,638
Options Outstanding, Number of Shares, Beginning Balances	2,957,754
Options Outstanding, Number of Shares, Granted	1,321,197
Options Outstanding, Number of Shares, Exercised	(146,916)
Options Outstanding, Number of Shares, Canceled	(48)
Options Outstanding, Number of Shares, Expired	0
Options Outstanding, Number of Shares, Ending Balances	4,131,987
Options Outstanding, Number of Shares, Vested and exercisable	4,131,987
Options Outstanding, Weighted-Average Exercise Price, Beginning Balances	$ 66.59
Options Outstanding, Weighted-Average Exercise Price, Granted	$ 75.95
Options Outstanding, Weighted-Average Exercise Price, Exercised	$ 14.06
Options Outstanding, Weighted-Average Exercise Price, Canceled	$ 35.95
Options Outstanding, Weighted-Average Exercise Price, Expired	$ 0.00
Options Outstanding, Weighted-Average Exercise Price, Ending Balances	$ 71.45
Options Outstanding, Weighted-Average Exercise Price, Vested and exercisable	$ 71.45
Weighted-Average Remaining Contractual Term, Ending Balances (in Years)	6 years 11 months 19 days
Weighted-Average Remaining Contractual Term, Vested and exercisable (in Years)	6 years 11 months 19 days
Aggregate Intrinsic Value, Ending Balances	$ 50,057
Aggregate Intrinsic Value, Vested and exercisable	$ 50,057