Business and Basis of Presentation (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	Dec. 31, 2020
Organization And Basis Of Presentation [Line Items]
Accounts receivable, net	$ 683,319		$ 310,818
Net proceeds from issuance of stock and warrants	1,943,052	$ 4,197
Accumulated deficit	200,121,819		199,163,257
Cash and cash equivalents	23,769,380		22,572,104
Prepaid expenses and other current assets	(422,616)		(598,384)
Assets, Current	(25,587,251)		(24,187,859)
Accrued Sales Return provisions	11,000		39,000
Liabilities, Current	(1,727,254)		(1,365,697)
Operating Lease, Liability, Noncurrent	(283,209)		(306,709)
Stockholders' Equity Attributable to Parent	24,237,908	5,261,052	23,215,786	$ 5,247,775
Cost of revenues	508,874	576,289
Gross Profit	1,793,517	1,579,183
Compensation cost not yet recognized	$ 93,991
Compensation cost not yet recognized, period for recognition	3 years 4 months 24 days
Operating Lease, Right-of-Use Asset	$ (450,374)		(475,230)
Other long-term assets	(26,400)		(26,400)
Assets	(26,248,371)		(24,888,192)
Accrued Liabilities, Current	(1,207,008)		(814,155)
Liabilities	(2,010,463)		(1,672,406)
Allowance for doubtful accounts	25,000		$ 25,000
Other Comprehensive Income (Loss), Net of Tax	$ 0	$ 0
One Customer | Revenue | Customer Concentration Risk
Organization And Basis Of Presentation [Line Items]
Concentration risk, percentage	43.00%	36.00%
Three Customers [Member] | Accounts Receivable | Customer Concentration Risk
Organization And Basis Of Presentation [Line Items]
Concentration risk, percentage	55.00%
Two Customers | Accounts Receivable | Customer Concentration Risk
Organization And Basis Of Presentation [Line Items]
Concentration risk, percentage			35.00%