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Debt Financing and Revolving Credit Facilities (Long-Term Debt) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	May 14, 2021	Dec. 31, 2020	Nov. 24, 2020
Debt Instrument [Line Items]
Total Debt	$ 91,239		$ 66,979
Total debt, net of discount and deferred financing costs	80,881		55,273
Less amounts due within one year	(10,161)		(17,605)
Long-term debt, net of current portion	70,720		37,668
M&T Credit Agreement [Member]
Debt Instrument [Line Items]
Total Debt	10,161		10,105
Paycheck Protection Program Loan [Member]
Debt Instrument [Line Items]
Total Debt	0		10,000
Siena Loan Agreement [Member]
Debt Instrument [Line Items]
Total Debt	24,164		6,874
Term Loan Credit Agreement [Member]
Debt Instrument [Line Items]
Total Debt	56,914		40,000
discount	(7,531)		(8,892)
deferred financing costs	$ (2,827)	$ (480)	$ (2,814)	$ (2,872)