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Term Loan Obligations (Details) - USD ($)				12 Months Ended
	Mar. 29, 2020	Mar. 28, 2020	May 29, 2015	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Warrant exercise price (in dollars per share)				$ 2.25
Interest expense				$ 1,107,000	$ 1,855,000
Non-cash amortization				$ 600,000	$ 500,000
LIBOR [Member] | Interest Rate Floor [Member]
Debt Instrument [Line Items]
Basis variable rate			1.00%
Term Loan [Member]
Debt Instrument [Line Items]
Origination Date				May 29, 2015	May 29, 2015
Original Loan Amount			$ 17,700,000	$ 17,700,000	$ 17,700,000
Basis variable rate			7.95%
Maturity date	Sep. 01, 2024	Sep. 01, 2021	May 01, 2021
Fees amount associated with loan			$ 3,200,000	$ 3,200,000
Number of securities called by warrant or right			188
Warrant exercise price (in dollars per share)			$ 5,175
Date from which warrants are exercisable					Nov. 30, 2015
Warrant expiration date					May 29, 2025
Minimum liquidity covenant					$ 2,000,000
Debt principal repayment start date	May 01, 2021	May 01, 2020
Prepayments of term loan	$ 5,000,000
Related final payment	300,000
Term loan, remaining amount	4,300,000
Amendment fee	$ 1,000,000
Debt Instrument, Covenant Compliance				the Company was in compliance with all of the debt covenants under the Loan and Security Agreement.
Term Loan [Member] | Loan and Security Agreement [Member] | Sale of the Japanese Subsidiary and Certain Assets [Member]
Debt Instrument [Line Items]
Payments for principal, interest and fees			$ 3,100,000
Minimum [Member] | Term Loan [Member]
Debt Instrument [Line Items]
Interest rate			8.95%
Maximum [Member] | Term Loan [Member]
Debt Instrument [Line Items]
Original Loan Amount				$ 3,000,000
Long Term Debt Outstanding Threshold Amount				$ 4,300,000

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