CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 6,397	$ 9,705
Restricted cash	206	2,892
Accounts receivable, net of allowance for doubtful accounts of $2,531 and $2,636, as of March 31, 2019 and December 31, 2018, respectively	15,412	16,120
Inventories	20,954	16,296
Prepaid expenses and other receivables	2,806	3,373
Total current assets	45,775	48,386
Property, plant and equipment, net	94,392	91,775
Intangible assets, net	46,818	48,375
Goodwill	480	470
Other assets	4,397	1,886
Total assets	191,862	190,892
Current liabilities:
Accounts payable	7,555	5,933
Accrued expenses	9,303	9,842
Deferred income	1,875	2,426
Convertible 3.75% Senior Notes, net of debt discount and debt issuance costs (face of $13,022 and $15,702 as of March 31, 2019 and December 31, 2018, respectively)	12,214	14,411
Other current liabilities	407	0
Total current liabilities	31,354	32,612
Convertible 4.75% Senior Notes, net of debt discount and debt issuance costs (face of $75,090 as of March 31, 2019 and December 31, 2018, respectively)	57,723	56,909
Revolver, net of debt issuance costs (face of $20,000 and $15,000 as of March 31, 2019 and December 31, 2018, respectively)	20,000	15,000
2023 Term Loan, net of debt issuance costs (face of $72,020 and $70,000 as of March 31, 2019 and December 31, 2018, respectively)	69,766	67,662
Deferred tax liability	220	215
Other long term liabilities	2,579	73
Total liabilities	181,642	172,471
Commitments and Contingencies
Stockholders’ equity:
Common stock, $0.01 par value, 100,000,000 shares authorized; 53,845,427 and 53,774,221 shares issued and outstanding as of March 31, 2019 and December 31, 2018, respectively	558	557
Additional paid-in capital	117,239	116,864
Accumulated deficit	(105,074)	(96,350)
Accumulated other comprehensive loss	(2,503)	(2,650)
Total stockholders’ equity	10,220	18,421
Total liabilities and stockholders' equity	$ 191,862	$ 190,892