Share Based Compensation (Details 2) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Stock Options Outstanding Summary [Line Items]
Balance,	2,230	3,504	4,213
Exercise Price, Lower Range Limit	$ 16.97	$ 3.91	$ 1.49	$ 0.25
Exercise Price, Upper Range Limit	$ 98.87	$ 98.87	$ 98.87	$ 98.87
Granted			0
Exercise Price, Lower Range Limit Granted			$ 0
Exercise Price, Upper Range Limit Granted			$ 0
Forfeited	(99)	(68)	(43)
Exercise Price, Lower Range Limit Forfeited	$ 51.60	$ 51.60	$ 51.60
Exercise Price, Upper Range Limit Forfeited	$ 75.18	$ 76.01	$ 78.55
Exercised	(672)	(1,206)	(666)
Exercise Price, Lower Range Limit Exercised	$ 3.91	$ 1.49	$ 0.25
Exercise Price, Upper Range Limit Exercised	$ 33.57	$ 45.95	$ 33.57
Balance,	1,459	2,230	3,504	4,213