Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities:
Net loss	$ (68,552)	$ (67,657)	$ (51,013)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	4,392	5,209	4,142
Depreciation and amortization	2,366	1,497	1,121
Non-cash interest expense	271	302	247
Deferred income tax	6	(1,548)	(11,435)
Other	11		(3)
Intangible impairment charge		23,200
Change in fair value of contingent consideration liability	916	(5,800)	2,600
Changes in assets and liabilities:
Accounts receivable	(12,176)	204	892
Other current assets	(2,898)	(403)	2,046
Other assets	(2,035)	(150)	468
Accounts payable	808	(2,906)	2,779
Accrued expenses	2,612	1,009	(6,274)
Other current liabilities	80
Other liabilities	(499)	291	323
Net cash used in operating activities	(74,698)	(46,752)	(54,107)
Cash flows from investing activities:
Acquisition of AZEDRA manufacturing assets	(8,000)
Purchases of property and equipment	(7,231)	(817)	(269)
Portion of MIP milestones paid to former advisor	(277)
Proceeds from sale of fixed assets			37
Net cash used in investing activities	(15,508)	(817)	(232)
Cash flows from financing activities:
Repayment of debt	(5,843)	(5,390)
Proceeds from exercise of stock options	1,942	467	469
Return of estimated interest payment for noncontrolling interest			15
Net cash (used in) provided by financing activities	(3,901)	94,717	5,510
Effect of currency rate changes on cash, cash equivalents and restricted cash	(48)	(92)	83
Net decrease in cash, cash equivalents, and restricted cash	(94,155)	47,056	(48,746)
Cash, cash equivalents, and restricted cash at beginning of period	139,220	92,164	140,910
Cash, cash equivalents, and restricted cash at end of period	45,065	139,220	92,164
Supplemental disclosure of cash flow information
Cash paid for interest	4,131	4,660	4,821
Noncash financing activity
Subscription receivable		(2,109)	2,109
Cash and cash equivalents at beginning of period	137,686	90,642
Restricted cash included in long-term assets at the beginning of period	1,534	1,522
Cash, cash equivalents, and restricted cash at beginning of period	139,220	92,164	140,910
Cash and cash equivalents at end of period	42,049	137,686	90,642
Restricted cash included in long-term assets at the end of period	3,016	1,534	1,522
Cash, cash equivalents, and restricted cash at end of period	45,065	139,220	92,164
Public Offering [Member]
Cash flows from financing activities:
Net proceeds common stock		69,987
At-the-market Offering [Member]
Cash flows from financing activities:
Net proceeds common stock		$ 29,653	$ 5,026