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Term Loan Obligations (Details) - USD ($)				3 Months Ended		6 Months Ended
	Mar. 29, 2020	Mar. 28, 2020	May 29, 2015	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Sep. 30, 2020
Debt Instrument [Line Items]
Maturity date	Sep. 01, 2024	Sep. 01, 2021
Warrant exercise price (in dollars per share)								$ 2.25
Prepayments of term loan	$ 5,000,000.0		$ 3,100,000
Minimum liquidity covenant			$ 2,000.0
Debt principal repayment start date	May 01, 2021	May 01, 2020
Related final payment	$ 300,000
Term loan, remaining amount	4,300,000
Amendment fee	$ 1,000,000.0
Interest expense				$ 229,000	$ 252,000	$ 476,000	$ 601,000
Non-cash amortization				100,000	$ 200,000	300,000	$ 300,000
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			Sep. 01, 2024
Fees amount associated with loan			$ 3,200,000	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
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				$ 4,300,000		$ 4,300,000
Long Term Debt Outstanding Threshold Amount						$ 3,000,000

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