Share-Based Compensation (Details) (USD $)	12 Months Ended
	Dec. 31, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Number of Outstanding Options	5,886,939
Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	5 years 11 months
Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 10.64
Exercise Price Range, Number of Exercisable Options	3,512,257
Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 10.53
Stock Options [Member] | Range One [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	$ 4.72
Exercise Price Range, Upper Range Limit	$ 7.00
Exercise Price Range, Number of Outstanding Options	132,020
Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	3 years 5 months 19 days
Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 6.63
Exercise Price Range, Number of Exercisable Options	132,020
Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 6.63
Stock Options [Member] | Range Two [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	$ 7.01
Exercise Price Range, Upper Range Limit	$ 7.46
Exercise Price Range, Number of Outstanding Options	298,340
Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	4 years 1 month
Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 7.25
Exercise Price Range, Number of Exercisable Options	293,380
Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 7.25
Stock Options [Member] | Range Three [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	$ 7.49
Exercise Price Range, Upper Range Limit	$ 8.00
Exercise Price Range, Number of Outstanding Options	288,283
Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	4 years 5 months
Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 7.82
Exercise Price Range, Number of Exercisable Options	283,803
Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 7.82
Stock Options [Member] | Range Four [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	$ 8.01
Exercise Price Range, Upper Range Limit	$ 9.00
Exercise Price Range, Number of Outstanding Options	151,588
Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	3 years 7 months
Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 8.54
Exercise Price Range, Number of Exercisable Options	141,785
Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 8.53
Stock Options [Member] | Range Five [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	$ 9.01
Exercise Price Range, Upper Range Limit	$ 10.00
Exercise Price Range, Number of Outstanding Options	1,282,671
Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	6 years 6 months
Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 9.61
Exercise Price Range, Number of Exercisable Options	643,954
Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 9.65
Stock Options [Member] | Range Six [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	$ 10.01
Exercise Price Range, Upper Range Limit	$ 11.00
Exercise Price Range, Number of Outstanding Options	1,982,999
Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	6 years 9 months
Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 10.41
Exercise Price Range, Number of Exercisable Options	868,161
Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 10.40
Stock Options [Member] | Range Seven [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	$ 11.01
Exercise Price Range, Upper Range Limit	$ 13.00
Exercise Price Range, Number of Outstanding Options	697,258
Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	6 years 0 months
Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 12.09
Exercise Price Range, Number of Exercisable Options	407,874
Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 12.16
Stock Options [Member] | Range Eight [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	$ 13.01
Exercise Price Range, Upper Range Limit	$ 16.00
Exercise Price Range, Number of Outstanding Options	973,780
Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	5 years 6 months
Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 13.70
Exercise Price Range, Number of Exercisable Options	661,280
Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 13.67
Stock Options [Member] | Range Nine [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Range, Lower Range Limit	$ 16.01
Exercise Price Range, Upper Range Limit	$ 49.50
Exercise Price Range, Number of Outstanding Options	80,000
Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	1 year 2 months
Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 16.21
Exercise Price Range, Number of Exercisable Options	80,000
Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 16.21