Debt instrument covenant unrestricted cash.

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Number of customer.

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Extended line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Working capital.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of obligation due after one year or beyond the normal operating cycle, if longer.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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The cash inflow from bank borrowing during the year.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Description of Business, Basis of Presentation and Principles of Consolidation - Additional Information (Details)		3 Months Ended		12 Months Ended
	Apr. 21, 2020 USD ($)	Mar. 31, 2021 USD ($) Segment Customer	Mar. 31, 2020 Customer	Dec. 31, 2020 USD ($) Customer
Significant Accounting Policies [Line Items]
Number of operating segments \| Segment		1
Accumulated deficit		$ (196,036,168)		$ (191,187,861)
Working capital		26,800,000
Long-term liabilities		11,500,000
Debt instrument, covenant unrestricted cash		$ 12,500,000
Paycheck Protection Program Loan \| Silicon Valley Bank
Significant Accounting Policies [Line Items]
Proceeds from PPP Loan	$ 1,700,000
Sales Revenue, Net \| Customer Concentration Risk
Significant Accounting Policies [Line Items]
Number of customers \| Customer		2	3
Sales Revenue, Net \| Customer Concentration Risk \| Customers Located Outside Of United States
Significant Accounting Policies [Line Items]
Sales revenue percentage		41.00%	32.00%
Sales Revenue, Net \| Customer Concentration Risk \| Customer One
Significant Accounting Policies [Line Items]
Sales revenue percentage		19.00%	28.00%
Sales Revenue, Net \| Customer Concentration Risk \| Customer Two
Significant Accounting Policies [Line Items]
Sales revenue percentage		15.00%	17.00%
Sales Revenue, Net \| Customer Concentration Risk \| Customer Three
Significant Accounting Policies [Line Items]
Sales revenue percentage			11.00%
Accounts Payable \| Customer Concentration Risk
Significant Accounting Policies [Line Items]
Number of customers \| Customer		2		2
Accounts Payable \| Customer Concentration Risk \| Customer One
Significant Accounting Policies [Line Items]
Sales revenue percentage		16.00%		21.00%
Accounts Payable \| Customer Concentration Risk \| Customer Two
Significant Accounting Policies [Line Items]
Sales revenue percentage		11.00%		20.00%
Accounts Receivable \| Customer Concentration Risk
Significant Accounting Policies [Line Items]
Number of customers \| Customer				2
Accounts Receivable \| Customer Concentration Risk \| Customer One
Significant Accounting Policies [Line Items]
Sales revenue percentage		22.00%		9.00%
Accounts Receivable \| Customer Concentration Risk \| Customer Two
Significant Accounting Policies [Line Items]
Sales revenue percentage		14.00%		9.00%
Accounts Receivable \| Customer Concentration Risk \| Customer Three
Significant Accounting Policies [Line Items]
Sales revenue percentage		13.00%