Share-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation expenses [Abstract]
Total share-based compensation expenses		$ 6,581	$ 7,071
Performance Unit and Option Awards [Abstract]
Shares available for grant (in shares)		700,000
Manufacture and Supply [Member]
Share-based Compensation expenses [Abstract]
Total share-based compensation expenses		$ 275	231
Research and Development [Member]
Share-based Compensation expenses [Abstract]
Total share-based compensation expenses		729	720
Selling, General and Administrative [Member]
Share-based Compensation expenses [Abstract]
Total share-based compensation expenses		$ 5,577	6,120
Restricted Stock Units [Member]
Share-based Compensation expenses [Abstract]
Service period		3 years
Total share-based compensation expenses	[1]	$ 806	$ 1,863
Number of Units [Roll Forward]
Unvested, at beginning of period (in shares)		74,000	205,000
Granted (in shares)		4,000	0
Forfeited (in shares)		0	(6,000)
Vested (in shares)		(64,000)	(125,000)
Unvested, at end of period (in shares)		14,000	74,000	205,000
Weighted Average Grant Date Fair Value Per Share [Abstract]
Unvested, Balance at beginning of period (in dollars per share)		$ 14.64	$ 14.77
Granted (in dollars per share)		7.54	0
Forfeited (in dollars per share)		0	0
Vested (in dollars per share)		14.88	14.94
Unvested, Balance at end of period (in dollars per share)		11.38	14.64	$ 14.77
Aggregate Intrinsic Value [Abstract]
Weighted average grant date fair value (in dollars per share)		$ 7.54	$ 0
Additional Disclosures [Abstract]
Grant date fair value		$ 958	$ 1,863
Compensation Cost Not yet Recognized [Abstract]
Unrecognized stock-based compensation expense		$ 122
Restricted Stock Units [Member] | Senior Management and Board [Member]
Additional Disclosures [Abstract]
Vesting period		3 years
Restricted Stock Units [Member] | Key Employees [Member]
Additional Disclosures [Abstract]
Vesting period		3 years
Stock Options [Member]
Share-based Compensation expenses [Abstract]
Service period		3 years
Total share-based compensation expenses	[2]	$ 5,751	$ 5,173
Weighted Average Grant Date Fair Value Per Share [Abstract]
Granted (in dollars per share)		$ 2.61	$ 4.95
Number of Options [Roll Forward]
Outstanding at beginning of period (in shares)		2,231,000	1,033,000
Granted (in shares)		1,168,000	1,258,000
Forfeited (in shares)		(140,000)	(60,000)
Exercised (in shares)		0	0
Outstanding at end of period (in shares)		3,259,000	2,231,000	1,033,000
Vested or expected to vest at end of period (in shares)		3,035,000
Exercisable at end of period (in shares)		1,235,000
Weighted Average Exercise Price [Abstract]
Outstanding at beginning of period (in dollars per share)		$ 10.42	$ 14.72
Granted (in dollars per share)		3.32	6.66
Forfeited (in dollars per share)		4.36	5.78
Outstanding at end of period (in dollars per share)		8.14	$ 10.42	$ 14.72
Vested or expected to vest at end of period (in dollars per share)		8.14
Exercisable at end of period (in dollars per share)		$ 11.26
Weighted Average Remaining Contractual Term in Years [Abstract]
Outstanding at end of period		8 years 5 months 1 day	8 years 11 months 8 days	9 years 6 months 18 days
Vested or expected to vest at end of period		8 years 5 months 1 day
Exercisable at end of period		7 years 10 months 20 days
Aggregate Intrinsic Value [Abstract]
Intrinsic value of options exercised		$ 0
Outstanding at end of period		2,978	$ 689	$ 0
Vested or expected to vest at end of period		2,758
Exercisable at end of period		$ 403
Weighted average grant date fair value (in dollars per share)		$ 2.61	$ 4.95
Fair Value Assumptions [Abstract]
Expected dividend yield		0.00%	0.00%
Expected volatility		100.00%
Exercise prices (in dollars per share)		$ 3.32	$ 6.66
Compensation Cost Not yet Recognized [Abstract]
Unrecognized stock-based compensation expense		$ 5,653
Unrecognized compensation cost, recognition period		1 year 3 months 18 days
Term of award		10 years
Stock Options [Member] | Minimum [Member]
Weighted Average Exercise Price [Abstract]
Granted (in dollars per share)		$ 1.54	$ 3.36
Fair Value Assumptions [Abstract]
Expected volatility			85.00%
Expected term (in years)		5 years 6 months	5 years 6 months
Risk-free interest rate		0.33%	1.50%
Exercise prices (in dollars per share)		$ 1.54	$ 3.36
Stock Options [Member] | Maximum [Member]
Weighted Average Exercise Price [Abstract]
Granted (in dollars per share)		$ 7.86	$ 8.05
Fair Value Assumptions [Abstract]
Expected volatility			106.00%
Expected term (in years)		6 years 1 month 6 days	6 years 1 month 6 days
Risk-free interest rate		1.69%	2.60%
Exercise prices (in dollars per share)		$ 7.86	$ 8.05
Stock Options [Member] | Key Employees [Member]
Additional Disclosures [Abstract]
Vesting period		3 years
Stock Options [Member] | Board of Directors [Member]
Additional Disclosures [Abstract]
Vesting period		1 year
Employee Stock Purchase Plan [Member]
Share-based Compensation expenses [Abstract]
Total share-based compensation expenses	[3]	$ 24	$ 35
Employee Stock Purchase Plan [Abstract]
Purchase price of common stock as percentage of fair market value		85.00%
Number of shares reserved for issuance (in shares)		250,000
Shares issued under employee stock purchase plan (in shares)		32,986	56,378

[1] Restricted Stock Units

[2] Stock option awards

[3] Employee Stock Purchase Plan