Net Loss Per Common Share (Tables)

9 Months Ended

Sep. 30, 2013

Net Loss Per Common Share

Schedule of computation of basic and diluted net loss per share

	Three months ended September 30,						Nine months ended September 30,
	2013			2012			2013			2012
Basic and diluted net loss per common share calculation:
Net loss	$	(16,132	)	$	(4,153	)	$	(30,757	)	$	(10,731	)
Accretion of preferred stock dividends	(2,292		)	(1,775		)	(5,891		)	(5,288		)
Net loss attributable to common shareholders	$	(18,424	)	$	(5,928	)	$	(36,648	)	$	(16,019	)
Weighted average common shares outstanding	1,795			1,455			1,579			1,447
Net loss per share of common stock - basic and diluted	$	(10.26	)	$	(4.07	)	$	(23.21	)	$	(11.07	)

Schedule of potentially dilutive securities that have been excluded from the computations of diluted weighted average shares outstanding

	Three months ended September 30,		Nine months ended September 30,
	2013	2012	2013	2012
Redeemable convertible preferred stock	—	16,513	—	16,513
Stock options outstanding	2,620	1,301	2,620	1,301
Warrants	101	78	101	78
Total	2,721	17,892	2,721	17,892