CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) shares in Thousands, $ in Thousands	Total	Issuance of common stock to RPI Finance Trust	Common Stock	Common Stock Issuance of common stock to RPI Finance Trust	Capital Contributed in Excess of Par	Capital Contributed in Excess of Par Issuance of common stock to RPI Finance Trust	Treasury Stock	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest	Convertible Preferred Stock
Beginning balance (in shares) at Dec. 31, 2017			161,303								0
Beginning Balance at Dec. 31, 2017	$ 16,450		$ 1,613		$ 659,467		$ (458)	$ (642,973)	$ (401)	$ (798)	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reclassification of warrant liability to equity, net	137,976				137,976
Exercise of stock options (in shares)			403
Exercise of stock options, net	1,596		$ 4		1,592
Stock-based compensation (in shares)			284
Stock-based compensation	2,685		$ 3		2,682
Exercise of common stock warrants (in shares)			7,400
Exercise of common stock warrants	27,750		$ 74		27,676
Issuance of common stock (in shares)			13,225	4,373
Issuance of common stock	299,467	$ 67,784	$ 132	$ 44	299,335	$ 67,740
Conversion of RSU's for tax withholding payments (in shares)			(187)
Conversion of RSU's for tax withholding payments	(1,472)		$ (2)		(1,470)
Other comprehensive gain (loss)	48								48
Net loss	(152,598)							(152,575)		(23)
Ending balance (in shares) at Jun. 30, 2018			186,801								0
Ending Balance at Jun. 30, 2018	399,686		$ 1,868		1,194,998		(458)	(795,548)	(353)	(821)	$ 0
Beginning balance (in shares) at Mar. 31, 2018			167,256								0
Beginning Balance at Mar. 31, 2018	71,820		$ 1,672		750,392		(458)	(678,519)	(457)	(810)	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reclassification of warrant liability to equity, net	120,219				120,219
Exercise of stock options (in shares)			320
Exercise of stock options, net	1,262		$ 4		1,258
Stock-based compensation	1,354				1,354
Exercise of common stock warrants (in shares)			6,000
Exercise of common stock warrants	22,500		$ 60		22,440
Issuance of common stock (in shares)			13,225
Issuance of common stock	299,467		$ 132		299,335
Other comprehensive gain (loss)	104								104
Net loss	(117,040)							(117,029)		(11)
Ending balance (in shares) at Jun. 30, 2018			186,801								0
Ending Balance at Jun. 30, 2018	399,686		$ 1,868		1,194,998		(458)	(795,548)	(353)	(821)	$ 0
Beginning balance (in shares) at Dec. 31, 2018			190,446								0
Beginning Balance at Dec. 31, 2018	265,849		$ 1,905		1,219,237		(824)	(953,216)	(351)	(902)	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)			1,140
Exercise of stock options, net	2,106		$ 11		3,366		(1,271)
Stock-based compensation (in shares)			15
Stock-based compensation	4,147		$ 0		4,147
Issuance of common stock (in shares)			371
Issuance of common stock	5,829		$ 4		5,825
Other comprehensive gain (loss)	(14)								(14)
Net loss	(163,357)							(163,290)		(67)
Ending balance (in shares) at Jun. 30, 2019			191,972								0
Ending Balance at Jun. 30, 2019	114,560		$ 1,920		1,232,575		(2,095)	(1,116,506)	(365)	(969)	$ 0
Beginning balance (in shares) at Mar. 31, 2019			191,509								0
Beginning Balance at Mar. 31, 2019	181,804		$ 1,915		1,224,066		(2,095)	(1,040,553)	(560)	(969)	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)			77
Exercise of stock options, net	281		$ 1		280		0
Stock-based compensation (in shares)			15
Stock-based compensation	2,404		$ 0		2,404
Issuance of common stock (in shares)			371
Issuance of common stock	5,829		$ 4		5,825
Other comprehensive gain (loss)	195								195
Net loss	(75,953)							(75,953)		0
Ending balance (in shares) at Jun. 30, 2019			191,972								0
Ending Balance at Jun. 30, 2019	$ 114,560		$ 1,920		$ 1,232,575		$ (2,095)	$ (1,116,506)	$ (365)	$ (969)	$ 0