Stock-Based Compensation (Summary of Option Activity) (Details) - $ / shares	3 Months Ended	9 Months Ended
	Mar. 31, 2015	Sep. 30, 2015
2005 Plan [Member]
Stock Options
Outstanding at January 1, 2015	16,928,098	16,928,098
Granted		22,500
Exercised		(1,159,395)
Canceled		(191,250)
Outstanding at September 30, 2015		15,599,953
Shares exercisable at September 30, 2015		8,275,828
Weighted-Average Exercise Price
Outstanding at January 1, 2015	$ 3.24	$ 3.24
Granted		6.70
Exercised		2.30
Canceled		3.71
Outstanding at September 30, 2015		3.30
Shares exercisable at September 30, 2015		$ 2.53
1995 Plan [Member]
Stock Options
Outstanding at January 1, 2015	35,000	35,000
Granted		0
Exercised		(35,000)
Canceled		0
Outstanding at September 30, 2015		0
Shares exercisable at September 30, 2015		0
Weighted-Average Exercise Price
Outstanding at January 1, 2015	$ 2.21	$ 2.21
Granted		0
Exercised		2.21
Canceled		0
Outstanding at September 30, 2015		0
Shares exercisable at September 30, 2015		$ 0
2015 Plan [Member]
Stock Options
Outstanding at January 1, 2015	0	0
Granted	7,014,441	7,661,441
Exercised		0
Canceled		(102,188)
Outstanding at September 30, 2015		7,559,253
Shares exercisable at September 30, 2015		240,000
Shares available for grant at September 30, 2015		17,440,747
Weighted-Average Exercise Price
Outstanding at January 1, 2015	$ 0	$ 0
Granted	$ 8.94	9.02
Exercised		0
Canceled		9.00
Outstanding at September 30, 2015		9.02
Shares exercisable at September 30, 2015		$ 8.94