Stock-Based Compensation (Details Textuals 1) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended	12 Months Ended	3 Months Ended	6 Months Ended	12 Months Ended	0 Months Ended	6 Months Ended				3 Months Ended
	Jun. 30, 2014	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014 Restricted Stock Units (RSUs) [Member]	Jun. 30, 2014 Restricted Stock Units (RSUs) [Member]	Dec. 31, 2013 Restricted Stock Units (RSUs) [Member]	Mar. 01, 2013 Performance-Based Restricted Stock Units [Member]	Jun. 30, 2014 Vesting in One Year [Member] Performance-Based Restricted Stock Units [Member]	Jun. 30, 2014 Vesting in One Year [Member] Total Stockholder Return Performance-Based Restricted Stock Units [Member]	Jun. 30, 2014 Vesting in Two Years [Member] Performance-Based Restricted Stock Units [Member]	Jun. 30, 2014 Vesting in Two Years [Member] Total Stockholder Return Performance-Based Restricted Stock Units [Member]	Jun. 30, 2014 Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Document Period End Date		Jun. 30, 2014
Number of common stock issued to exercise stock options	74,000	478,000	177,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period												4 years 0 months
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Percentage Of Target Number Of Shares Eligible To Receive												250.00%
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 42.1	$ 42.1
Number of shares of common stock issued upon vesting of RSUs				145,000	1,355,000	665,000
Current Fiscal Year End Date		--12-31
Vesting percentage							33.33333%	33.33333%	50.00%	33.33333%	50.00%