Summary of Significant Accounting Policies - Narrative (Details)	1 Months Ended			12 Months Ended
	Sep. 30, 2020 USD ($)	Jan. 31, 2020 USD ($)	Oct. 31, 2014 USD ($)	Dec. 31, 2021 USD ($) agreement	Dec. 31, 2020 USD ($)	Dec. 31, 2017 USD ($)	Jun. 30, 2021 USD ($)
Accounting Policies [Abstract]
Number of distribution and license agreements | agreement				5
Customers average payment term				30 days
Distributors average payment term				45 days
Summary of significant accounting policies
Net revenue				$ 61,931,000	$ 62,197,000
Impairment losses				0	0
Bad-debt expense				0	0
Contract assets				0	0
Revenue performance obligation				8,200,000	10,200,000
Impairments of long-lived assets				$ 0	0
Finite-lived intangible asset useful life				17 years
Recognized revenue				$ 1,900,000	2,000,000
Contract liabilities				8,157,000	10,190,000
Research and product development expense				6,835,000	7,092,000
Baxter Healthcare Organization
Summary of significant accounting policies
Revenue performance obligation				5,200,000
Distribution agreement term			10 years
Upfront payment			$ 20,000,000
Contract liabilities				5,200,000	7,200,000
Wanbang Biopharmaceutical
Summary of significant accounting policies
Upfront payment						$ 4,000,000
Recognized revenue				200,000	200,000
Contract liabilities				2,500,000	2,700,000
Sun Pharma Agreements
Summary of significant accounting policies
Upfront payment		$ 100,000
Recognized revenue				10,000	10,000
Contract liabilities				80,000	90,000
Jeil Pharma Agreements
Summary of significant accounting policies
Upfront payment	$ 200,000
Recognized revenue				10,000	2,500
Contract liabilities				187,500	197,500
Drogsan Pharma Agreements
Summary of significant accounting policies
Recognized revenue				7,500
Contract liabilities				$ 100,000			$ 150,000
Minimum
Summary of significant accounting policies
Property and equipment useful life				3 years
Market and performance-based stock unit awards service period				1 year
Maximum
Summary of significant accounting policies
Property and equipment useful life				10 years
Market and performance-based stock unit awards service period				2 years
License
Summary of significant accounting policies
Net revenue				$ 2,200,000	2,200,000
Product
Summary of significant accounting policies
Net revenue				59,700,000	60,000,000
Upfront Fee | Baxter Healthcare Organization
Summary of significant accounting policies
Recognized revenue				1,900,000	2,000,000
Concentrate Products
Summary of significant accounting policies
Net revenue				60,855,000	61,061,000
Reserve for returns				$ 0	$ 0