Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Cash flows from operating activities
Net income (loss)	$ 22,069	$ (24,210)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation and amortization	7,362	7,115
Non-cash lease expense	1,640	2,066
Gain (loss) on sale of assets	37	(8)
Amortization of debt discount and debt issuance costs	502	1,425
Deferred income taxes	31	(189)
Stock-based compensation expense	349	399
Non-cash interest expense	3,658	1,347
Bad debt expense	1
Change in fair value of embedded derivative liability	(96)	154
Change in fair value of warrant liabilities	(1,762)	(7,260)
Change in fair value of contingent consideration		296
(Gain) loss on extinguishment of debt	(790)	10,056
Changes in assets and liabilities
Accounts receivable - trade	(9,798)	370
Alternative fuels tax credit receivable	817	976
Due from related party	30	(1)
Other assets	(3,252)	(1,640)
Accounts payable	(943)	(5,471)
Accrued expenses and other current liabilities	(5,264)	(2,122)
Accrued interest - related party	220	476
Operating lease liabilities	(3,207)	(2,160)
Net cash provided by (used in) operating activities	11,604	(18,381)
Cash flows from investing activities
Purchases of equipment	(4,814)	(61)
Proceeds from sale of assets	214	8
Net cash provided by (used in) investing activities	(4,600)	(53)
Cash flows from financing activities
Proceeds from sale of common stock, preferred stock and warrants		6,150
Proceeds from issuance of debt	3,658	10,000
Payments of principal on debt	(2,931)	(3,230)
Proceeds from issuance of debt - related party		6,150
Payments of principal on debt - related party	(18,435)	(171)
Payment of prepayment penalty fees - related party	(777)
Advances from factoring arrangements	103,885	90,433
Payments on factoring arrangements	(105,365)	(87,009)
Debt issuance costs		(296)
Payments on finance lease liabilities	(1,257)	(1,388)
Net cash provided by (used in) financing activities	(21,222)	20,639
Net increase in cash	(14,218)	2,205
Cash - beginning of year	26,644	3,274
Cash - end of year	12,426	5,479
Supplemental disclosures of cash flow information:
Income tax paid	596
Interest paid	253	2,670
Supplemental schedule of non-cash investing and financing activities:
Right-of-use assets obtained in exchange for finance lease liabilities	810	16,991
Right-of-use assets obtained in exchange for operating lease liabilities	1,061	3,379
Fair value of warrants and common stock issued in connection with financing arrangements	$ 2,208
Held-for-sale assets sold for noncash consideration		$ 450