Share-Based Compensation (Details 1) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011 Y
Summary of options outstanding
Number of options outstanding	3,775,930
Number of options exercisable	2,542,622
Price Range One [Member]
Summary of options outstanding
Exercise price, lower range limit	$ 6.26
Exercise price, upper range limit	$ 7.97
Number of options outstanding	706,928
Weighted-Average Remaining Contractual Life, Options Outstanding	1.0
Weighted-Average Exercise Price	$ 7.01
Number of options exercisable	706,928
Weighted-Average Exercise Price, Exercisable	$ 7.01
Price Range Two [Member]
Summary of options outstanding
Exercise price, upper range limit	$ 30.70
Exercise price, lower range limit	$ 15.33
Number of options outstanding	3,069,002
Weighted-Average Remaining Contractual Life, Options Outstanding	2.3
Weighted-Average Exercise Price	$ 16.29
Number of options exercisable	1,835,694
Weighted-Average Exercise Price, Exercisable	$ 17.91