Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	0 Months Ended	1 Months Ended	3 Months Ended		9 Months Ended	12 Months Ended
	Jul. 26, 2013	Oct. 31, 2009	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2013 Customer Segment Unit	Dec. 31, 2012	Dec. 31, 2011
Schedule Of Significant Accounting Policies [Line Items]
Stockholders reverse stock split	1-for-8
Stockholders reverse stock split, ratio	0.125
Stock split effective date	Aug. 09, 2013
Number of operating segment						1
Foreign currency re-measurement loses						$ 47,000.0	$ 100,000	$ 300,000
Short-term investments				15,433,967		0	15,433,967
Common stock, shares issued		1,362,500		10,942,973		12,151,670	10,942,973
Warrants to purchase common stock, in shares		681,275
Derivative liability, fair value, gross liability			696,065	1,173,747	696,065	379,468	1,173,747
Derivative gain (loss) fair value of stock warrants			(427,656)		(477,682)	794,280	6,995,099	(2,164,543)
Expense (income) recognized on adjustment of fair value of stock warrant liability					(477,682)	(794,280)	(6,995,099)	2,164,543
Reserves for excess and obsolete inventory				1,100,000		200,000	1,100,000
Net of allowance for doubtful accounts				1,159,145		7,197,032	1,159,145
Unbilled accounts receivable				0		2,800,000	0
Write-down of impaired assets				900,000			889,869
Number of major customers						2
Number of reporting unit						1
Goodwill impaired						0
Number of months before product expiration during which customer can return product						3 months
Number of months after product expiration during which customer can return product						12 months
Reimbursements recorded as reduction to research and development expense							(400,000)	(3,200,000)
Share based compensation						475,303	668,392	814,520
Weighted average period to recognize unamortized share-based compensation cost related to non-vested stock options						4 years 6 months 11 days
Cash received from option exercised						10,718	0	2,641,950
Company options granted to employees, in shares						88,749	104,375	129,375
Share based compensation expense allocation						475,303	668,392	814,520
Tax benefit recognized						0	0	0
Weighted average grant date fair values of options granted						$ 3.52	$ 3.68	$ 10.56
Antidilutive securities excluded from computation of earnings per share						1,599,551	1,841,857	769,757
Milestone 1 [Member]
Schedule Of Significant Accounting Policies [Line Items]
Discount volume levels						10,000,000
Milestone 2 [Member]
Schedule Of Significant Accounting Policies [Line Items]
Discount volume levels						20,000,000
Milestone 3 [Member]
Schedule Of Significant Accounting Policies [Line Items]
Discount volume levels						30,000,000
Minimum [Member]
Schedule Of Significant Accounting Policies [Line Items]
Finite-lived intangible asset, useful life						3 years
Minimum [Member] | Merck Serono [Member]
Schedule Of Significant Accounting Policies [Line Items]
Revenue recognition, recorded revenue cost plus percentage						20.00%
Maximum [Member]
Schedule Of Significant Accounting Policies [Line Items]
Finite-lived intangible asset, useful life						7 years
Maximum [Member] | Merck Serono [Member]
Schedule Of Significant Accounting Policies [Line Items]
Revenue recognition, recorded revenue cost plus percentage						30.00%
Consultants [Member]
Schedule Of Significant Accounting Policies [Line Items]
Share based compensation expense allocation						0	100,000	100,000
Stock Options [Member]
Schedule Of Significant Accounting Policies [Line Items]
Unamortized share-based compensation cost related to non-vested stock options not yet recognized						500,000
Weighted average period to recognize unamortized share-based compensation cost related to non-vested stock options						2 years 2 months 12 days
Credit to compensation related costs forfeited options							200,000
Molecular Profiles [Member]
Schedule Of Significant Accounting Policies [Line Items]
Assumed obligation under grant arrangement by the entity						3,889,486
Molecular Profiles [Member] | Regional Growth Fund [Member]
Schedule Of Significant Accounting Policies [Line Items]
Assumed obligation under grant arrangement by the entity						2,500,000
Deferred revenue						$ 2,600,000