Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Current assets
Cash	$ 12,426	$ 26,644
Accounts receivable - trade, net	22,829	13,033
Alternative fuels tax credit receivable	237	1,054
Due from related party	10	40
Prepaids and other current assets	4,389	2,205
Total current assets	39,891	42,976
Non-current assets
Property and equipment, net	29,075	28,240
Goodwill	23,837	23,837
Intangible assets, net	4,631	5,087
Operating lease right-of-use assets, net	8,213	10,473
Finance lease right-of-use assets, net	25,350	27,913
Deposits and other long-term assets	4,865	3,797
Total non-current assets	95,971	99,347
Total assets	135,862	142,323
Current liabilities
Accounts payable	10,943	11,698
Accrued expenses and other current liabilities	12,891	18,589
Accrued interest - related party	2,469	2,249
Embedded derivative liability	2,182	2,278
Warrant liabilities	9,502	11,264
Advances under factoring arrangements, current portion	17,373	24,397
Current portion of long-term debt	30,412	12,727
Current portion of long-term debt - related party	24,170	50,252
Operating lease liabilities, current portion	3,618	3,801
Finance lease liabilities, current portion	4,459	4,597
Total current liabilities	118,019	141,852
Non-current liabilities
Advances under factoring arrangements, less current portion	6,069
Long-term debt, less current portion	7,699	24,737
Long-term debt, less current portion - related party	11,399	3,379
Operating lease liabilities, less current portion	4,589	6,553
Finance lease liabilities, less current portion	22,512	24,884
Deferred tax liability	48	17
Total non-current liabilities	52,316	59,570
Total liabilities	170,335	201,422
Commitments and contingencies (Note 11)
Stockholders’ deficit
Common stock, $0.0001 par value; 100,000,000 shares authorized; 12,972,815 (June 30, 2021 and December 31, 2020) shares issued and outstanding	2	2
Common stock issuable	4,390	3,474
Additional paid-in capital	32,139	30,821
Accumulated deficit	(79,550)	(101,619)
Total stockholders’ deficit	(43,019)	(67,322)
Total liabilities, temporary equity, and stockholders' deficit	135,862	142,323
Series A Redeemable Convertible Preferred Stock [Member]
Temporary Equity
Redeemable stock	416	398
Series B Redeemable Convertible Preferred Stock [Member]
Temporary Equity
Redeemable stock	6,930	6,625
Redeemable Common Stock [Member]
Temporary Equity
Redeemable stock	$ 1,200	$ 1,200