Equity (Details) (USD $)	3 Months Ended			9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013	Sep. 30, 2014 plan		Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share-based compensation plans				3
Outstanding assumed options (in shares)	375,000			375,000
Additional shares authorized by Board of Directors (in shares)				4,000,000
Shares authorized (in shares)	26,500,000			26,500,000
Total unrecognized compensation expense	$ 16,675,914			$ 16,675,914
Number of shares [Roll forward]
Outstanding, beginning of period (in shares)				15,375,960
Granted (in shares)				2,948,969
Exercised (in shares)				(1,146,987)
Unvested options forfeited (in shares)				(249,670)
Vested options expired (in shares)				(84,332)
Outstanding, end of period (in shares)	16,843,940			16,843,940
Vested at end of period (in shares)	8,987,368			8,987,368
Exercisable options, vested and expected to vest (in shares)	16,515,621	[1]		16,515,621	[1]
Weighted-Average Exercise Price [Roll forward]
Outstanding, weighted average exercise price, beginning of period (in dollars per share)				$ 2.46
Granted, weighted average exercise price (in dollars per share)				$ 7.03
Exercised, weighted average exercise price (in dollars per share)				$ 1.31
Unvested options forfeited weighted-average exercise price (in dollars per share)				$ 4.04
Vested options expired weighted-average exercise price (in dollars per share)				$ 0.81
Outstanding, weighted average exercise price, end of period (in dollars per share)	$ 3.32			$ 3.32
Vested at end of period weighted average exercise price (in dollars per share)	$ 1.87			$ 1.87
Vested and expected to vest, weighted average exercise price (in dollars per share)	$ 3.27	[1]		$ 3.27	[1]
Stock options, additional disclosures [Abstract]
Vested at end of period weighted average remaining contractual term				6 years 8 months 12 days
Vested and expected to vest, weighted average remaining contractual term				7 years 6 months	[1]
Outstanding intrinsic value	64,630,326			64,630,326
Vested at end of period aggregate intrinsic value	47,252,742			47,252,742
Vested and expected to vest, aggregate intrinsic value	64,242,362	[1]		64,242,362	[1]
Exercised options, intrinsic value				6,517,614
Number of outstanding options (in shares)	16,843,940			16,843,940
Outstanding Options, weighted average remaining contractual term				7 years 6 months
Outstanding Options, weighted average exercise price (in dollars per share)	$ 3.32			$ 3.32
Number of exercisable options (in shares)	8,987,368			8,987,368
Exercisable Options, weighted average exercise price (in dollars per share)	$ 1.87			$ 1.87
Fair value options valuation assumptions [Abstract]
Expected volatility Minimum				63.60%		61.41%
Expected volatility Maximum				64.50%		64.56%
Expected life (in years)						6 years
Expected dividend yield				0.00%		0.00%
Risk-free interest rate Minimum				1.69%		0.85%
Risk-free interest rate Maximum				1.96%		1.88%
Share-based Compensation [Abstract]
Share-based compensation expense	3,021,962		1,667,766	8,160,678		4,155,005
Weighted-average grant date fair value for options granted during the period (in dollars per share)				$ 4.09
Warrants, term				5 years
Warrants
Warrants, Number of Warrants [Roll Forward]
Warrants outstanding, beginning of period (in shares)				1,284,816
Warrants exercised (in shares)				(1,079,583)
Warrants outstanding, end of period (in shares)	205,233			205,233
Warrants, Weighted-Average Exercise Price per Warrant [Roll Forward]
Warrants outstanding, beginning of period (in dollars per share)				0.90
Warrants exercised (in dollars per share)				0.80
Warrants outstanding, end of period (in dollars per share)	1.42			1.42
Cost of Products Sold
Share-based Compensation [Abstract]
Share-based compensation expense	70,424		75,287	242,689		198,119
Research and Development
Share-based Compensation [Abstract]
Share-based compensation expense	170,426		110,694	493,078		309,461
Selling, General and Administrative
Share-based Compensation [Abstract]
Share-based compensation expense	2,781,112		1,481,785	7,424,911		3,647,425
$0.50 - $0.76
Stock options, additional disclosures [Abstract]
Exercise Price Range, lower range limit (in dollars per share)				$ 0.50
Exercise Price Range, upper range limit (in dollars per share)				$ 0.76
Number of outstanding options (in shares)	720,364			720,364
Outstanding Options, weighted average remaining contractual term				4 years 8 months 12 days
Outstanding Options, weighted average exercise price (in dollars per share)	$ 0.72			$ 0.72
Number of exercisable options (in shares)	720,364			720,364
Exercisable Options, weighted average exercise price (in dollars per share)	$ 0.72			$ 0.72
$0.87 - $1.35
Stock options, additional disclosures [Abstract]
Exercise Price Range, lower range limit (in dollars per share)				$ 0.87
Exercise Price Range, upper range limit (in dollars per share)				$ 1.35
Number of outstanding options (in shares)	6,102,250			6,102,250
Outstanding Options, weighted average remaining contractual term				6 years 10 months 24 days
Outstanding Options, weighted average exercise price (in dollars per share)	$ 1.20			$ 1.20
Number of exercisable options (in shares)	4,911,058			4,911,058
Exercisable Options, weighted average exercise price (in dollars per share)	$ 1.19			$ 1.19
$1.40 - $2.29
Stock options, additional disclosures [Abstract]
Exercise Price Range, lower range limit (in dollars per share)				$ 1.40
Exercise Price Range, upper range limit (in dollars per share)				$ 2.29
Number of outstanding options (in shares)	1,482,701			1,482,701
Outstanding Options, weighted average remaining contractual term				5 years 3 months 18 days
Outstanding Options, weighted average exercise price (in dollars per share)	$ 1.64			$ 1.64
Number of exercisable options (in shares)	1,361,032			1,361,032
Exercisable Options, weighted average exercise price (in dollars per share)	$ 1.65			$ 1.65
$2.33 - $3.75
Stock options, additional disclosures [Abstract]
Exercise Price Range, lower range limit (in dollars per share)				$ 2.35
Exercise Price Range, upper range limit (in dollars per share)				$ 3.75
Number of outstanding options (in shares)	1,842,320			1,842,320
Outstanding Options, weighted average remaining contractual term				8 years
Outstanding Options, weighted average exercise price (in dollars per share)	$ 2.77			$ 2.77
Number of exercisable options (in shares)	889,298			889,298
Exercisable Options, weighted average exercise price (in dollars per share)	$ 2.69			$ 2.69
$3.95 - $5.99
Stock options, additional disclosures [Abstract]
Exercise Price Range, lower range limit (in dollars per share)				$ 3.95
Exercise Price Range, upper range limit (in dollars per share)				$ 5.99
Number of outstanding options (in shares)	3,443,402			3,443,402
Outstanding Options, weighted average remaining contractual term				8 years 7 months 6 days
Outstanding Options, weighted average exercise price (in dollars per share)	$ 5.15			$ 5.15
Number of exercisable options (in shares)	911,797			911,797
Exercisable Options, weighted average exercise price (in dollars per share)	$ 5.02			$ 5.02
$6.02 - $8.34
Stock options, additional disclosures [Abstract]
Exercise Price Range, lower range limit (in dollars per share)				$ 6.02
Exercise Price Range, upper range limit (in dollars per share)				$ 8.34
Number of outstanding options (in shares)	3,252,903			3,252,903
Outstanding Options, weighted average remaining contractual term				9 years
Outstanding Options, weighted average exercise price (in dollars per share)	$ 7.03			$ 7.03
Number of exercisable options (in shares)	193,819			193,819
Exercisable Options, weighted average exercise price (in dollars per share)	$ 6.37			$ 6.37
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expenses expected to be recognized over a weighted-average period				2 years
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expenses expected to be recognized over a weighted-average period				2 years 1 month 6 days
Total unrecognized stock-based compensation related to time-based, nonvested restricted stock	4,983,312			4,983,312
Number of Shares
Beginning Balance				576,550
Granted				592,864
Vested				(154,758)
Forfeited				(720)
Ending Balance	1,013,936			1,013,936
Weighted- Average Grant Date Fair Value
Beginning Balance (in dollars per share)				$ 5.53
Granted (in dollars per share)				$ 7.05
Vested (in dollars per share)				$ 5.72
Forfeited (in dollars per share)				$ 7.24
Beginning Balance (in dollars per share)	$ 6.40			$ 6.40
Minimum
Fair value options valuation assumptions [Abstract]
Expected life (in years)				5 years
Maximum
Fair value options valuation assumptions [Abstract]
Expected life (in years)				6 years
Consultant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock issued				5,611
Value of common stock issued				$ 39,000

[1] Includes forfeiture adjusted unvested shares.