CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Cash provided by (used in) operating activities
Net loss	$ (5,584)	$ (26,009)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Amortization of intangible assets	1,819	2,366
Depreciation	2,605	2,524
Change in value and exercise of warrants	1,352	9,000
Stock-based compensation expense	928	1,418
Amortization of financing fees	361	659
Deferred income taxes	(458)	(208)
Other non-cash adjustments, net	(68)	325
Changes in operating assets and liabilities:
Accounts receivable, net	10,292	(1,739)
Inventory, net	(4,393)	(14,825)
Prepaid expenses and other assets	4,902	(4,815)
Accounts payable	(1,201)	13,200
Accrued expenses	(5,354)	7,914
Other noncurrent liabilities	(3,230)	1,998
Net cash provided by (used in) operating activities	1,971	(8,192)
Cash used in investing activities
Capital expenditures	(1,536)	(1,588)
Asset acquisitions	0	(6,595)
Net cash used in investing activities	(1,536)	(8,183)
Cash (used in) provided by financing activities
Proceeds from revolving line of credit	267,584	240,698
Repayments of revolving line of credit	(268,743)	(223,419)
Proceeds from Weichai Warrant exercise	1,616	0
Other financing activities, net	(896)	(902)
Net cash (used in) provided by financing activities	(439)	16,377
Net (decrease) increase in cash and restricted cash	(4)	2
Cash at beginning of the period	54	0
Cash at end of the period	$ 50	$ 2

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