Derivative Instruments (Tables)

12 Months Ended

Dec. 31, 2013

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Components of Derivative Instruments

Derivative instruments consist of the following:

	December 31,
	2013		2012
	(in thousands)
Amended and Restated Convertible Notes	$	10,371	$	230
Amended and Restated Reimbursement Notes		7		—
Amended and Restated Bridge Notes		960		—
Amended and Restated August 2009 Warrants		597		372
Amended and Restated June 2010 MHR Warrants		249		79
Amended and Restated August 2010 Warrants		420		277
August 2010 Investor Warrants		171		258
Amended and Restated August 2010 MHR Waiver Warrants		156		103
Amended and Restated July 2011 Warrants		482		340
July 2011 Investor Warrants		369		340
Amended and Restated July 2011 MHR Waiver Warrants		127		90
May 2013 MHR Modification Warrants		1,600		—
	$	15,509	$	2,089