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Term Loan Obligations (Details) - USD ($) $ / shares in Units, $ in Thousands				3 Months Ended		9 Months Ended
	Mar. 29, 2020	Mar. 28, 2020	May 29, 2015	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Debt Instrument [Line Items]
Maturity date	Sep. 01, 2024	Sep. 01, 2021
Warrant exercise price (in dollars per share)					$ 2.25		$ 2.25
Prepayments of term loan	$ 5,000		$ 3,100
Minimum liquidity covenant			$ 2,000
Debt principal repayment start date	May 01, 2021	May 01, 2020
Related final payment	$ 300
Term loan, remaining amount	4,300
Amendment fee	$ 1,000
Interest expense				$ 232	$ 253	$ 708	$ 854
Non-cash amortization				100	$ 100	400	$ 400
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
Basis variable rate			7.95%
Maturity date			Sep. 01, 2024
Fees amount associated with loan			$ 3,200	3,200		$ 3,200
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
Debt Instrument, Covenant Compliance						the Company was in compliance with all of the debt covenants under the Loan and Security Agreement.
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				$ 4,300		$ 4,300
Long Term Debt Outstanding Threshold Amount						$ 3,000

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