Revenue - Summary Current vs. Long Term Deferred Revenue (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Current portion	$ 354,756	$ 918,272
Long-term portion	0
Total	355,000	918,000	$ 1,212,000
NIH Grant
Disaggregation of Revenue [Line Items]
Current portion	355,000
Long-term portion	0
Total	355,000	918,000	568,000
BED
Disaggregation of Revenue [Line Items]
Current portion	0
Long-term portion	0
Total	$ 0	$ 0	$ 644,000

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130532-203044

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130531-203044

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130549-203045

Name:	us-gaap_ContractWithCustomerLiabilityNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant