Stock-Based Compensation (Schedule of Stock Options Outstanding Expected to Vest and Exercisable) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified					12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2012 Stock Based Options [Member]	Dec. 31, 2012 Stock Based Options [Member] Range of Exercise Price One [Member]	Dec. 31, 2012 Stock Based Options [Member] Range of Exercise Price Two [Member]	Dec. 31, 2012 Stock Based Options [Member] Range of Exercise Price Three [Member]	Dec. 31, 2012 Stock Based Options [Member] Range of Exercise Price Four [Member]	Dec. 31, 2012 Stock Based Options [Member] Range of Exercise Price Five [Member]	Dec. 31, 2012 Stock Based Options [Member] Range of Exercise Price Six [Member]	Dec. 31, 2012 Stock Based Options [Member] Range of Exercise Price Seven [Member]	Dec. 31, 2012 Stock Based Options [Member] Range of Exercise Price Eight [Member]	Dec. 31, 2012 Stock Based Options [Member] Range of Exercise Price Nine [Member]	Dec. 31, 2012 Stock Based Options [Member] Range of Exercise Price Ten [Member]
Number of Options (in thousands)					6,132	23	50	20	287	265	46	1,901	1,027	1,319	1,194
Weighted Average Remaining Contractual Life (in years)					3 years 8 months 9 days	1 year 8 months 16 days	7 years 0 months 7 days	2 months 16 days	8 years 1 month 17 days	7 months 25 days	4 years 10 months 10 days	2 years 4 months 17 days	3 years 11 months 23 days	5 years 1 month 21 days	3 years 5 months 9 days
Weighted Average Exercise Price					$ 26.43	$ 0.31	$ 0.82	$ 1.39	$ 2.81	$ 4.98	$ 9.38	$ 14.87	$ 24.83	$ 35.48	$ 49.32
Aggregate Intrinsic Value (in thousands)					$ 98,949	$ 948	$ 2,020	$ 774	$ 10,944	$ 9,530	$ 1,443	$ 49,493	$ 16,515	$ 7,282	$ 0
Exercisable Number of Options (in thousands)					4,814	23	20	20	79	265	29	1,866	779	788	945
Exercisable Weighted Average Remaining Contractual Life (in years)					3 years 1 month 6 days	1 year 8 months 16 days	7 years 0 months 29 days	2 months 16 days	6 years 11 months 16 days	7 months 25 days	2 years 9 months 29 days	2 years 4 months 10 days	3 years 8 months 23 days	4 years 8 months 19 days	3 years 1 month 2 days
Exercisable Weighted Average Exercise Price					$ 25.60	$ 0.31	$ 0.82	$ 1.39	$ 2.90	$ 4.98	$ 10.51	$ 14.83	$ 24.80	$ 34.33	$ 50.05
Exercisable Aggregate Intrinsic Value (in thousands)					$ 82,379	$ 948	$ 812	$ 774	$ 2,984	$ 9,530	$ 874	$ 48,660	$ 12,552	$ 5,245	$ 0
Exercise price range, lower limit						$ 0.20	$ 0.82	$ 1.33	$ 2.77	$ 4.29	$ 7.47	$ 12.14	$ 18.49	$ 28.13	$ 43.08
Exercise price range, upper limit						$ 0.31	$ 0.82	$ 1.49	$ 4.10	$ 5.56	$ 11.20	$ 18.01	$ 26.95	$ 42.10	$ 56.50
Expected forfeitures					91
Total options outstanding	6,223	8,017	8,946	10,022	6,223