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Term Loan Obligations (Details) - USD ($)				3 Months Ended
	Mar. 29, 2020	Mar. 28, 2020	May 29, 2015	Mar. 31, 2022	Mar. 31, 2021
Debt Instrument [Line Items]
Interest expense				$ 198,000	$ 247,000
Non-cash amortization				$ 100,000	$ 100,000
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
Original Loan Amount			$ 17,700,000
Basis variable rate			7.95%
Maturity date	Jun. 01, 2024	Sep. 01, 2021	May 01, 2021
Fees amount associated with loan			$ 3,200,000	$ 3,200,000
Number of shares callable by warrants (in shares)			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				$ 2,000,000.0
Debt principal repayment start date	May 01, 2021	May 01, 2020
Prepayments of term loan	$ 5,000,000.0
Related final payment	300,000
Amendment fee	$ 1,000,000.0
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
Term Loan [Member] | Minimum [Member]
Debt Instrument [Line Items]
Interest rate			8.95%
Term Loan [Member] | Maximum [Member]
Debt Instrument [Line Items]
Original Loan Amount				$ 3,000,000
Long Term Debt Outstanding Threshold Amount				$ 3,600,000

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