CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 63,357	$ 46,563
Restricted cash	485	971
Accounts receivable	14,836	5,339
Unbilled receivables	128	404
Inventories	8,811	10,344
Prepaid expenses and other current assets	4,818	1,403
Total current assets	92,435	65,024
Inventories, long-term		3,155
Property, plant and equipment, net	111,077	104,096
Deferred financing costs, net	1,125	1,154
Other assets	23	23
Total assets	204,660	173,452
Current liabilities:
Accounts payable	3,898	1,663
Accrued and other expenses	8,281	2,430
Deferred revenue	5	1,615
Income taxes payable		7,058
Current portion of equipment financing obligations	285	674
Current portion of notes payable		282
Total current liabilities	12,469	13,722
Equipment financing obligations, net of current portion	432	572
Notes payable, net of current portion	288	288
Deferred tax liabilities, long-term, net	19,202	15,044
Asset retirement obligation	1,425	1,384
Total liabilities	33,816	31,010
Commitments and contingencies (Note 20)
Stockholders’ equity
Common stock, $0.001 par value, 350,000,000 shares authorized; 40,453,735 issued and 40,372,683 outstanding at June 30, 2017; 38,884,068 issued and 38,816,474 outstanding at December 31, 2016	40	39
Treasury stock, at cost, 81,052 and 67,594 shares at June 30, 2017 and December 31, 2016, respectively	(666)	(539)
Additional paid-in capital	157,807	132,879
Retained earnings	13,663	10,063
Total stockholders’ equity	170,844	142,442
Total liabilities and stockholders’ equity	$ 204,660	$ 173,452

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Balance Type:	credit
Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.