CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 34,740	$ 46,563
Restricted cash	487	971
Accounts receivable	23,377	5,339
Unbilled receivables	1,192	404
Inventories	9,092	10,344
Prepaid expenses and other current assets	3,849	1,403
Total current assets	72,737	65,024
Inventories, long-term		3,155
Property, plant and equipment, net	172,202	104,096
Deferred financing costs, net	892	1,154
Other assets	971	23
Total assets	246,802	173,452
Current liabilities:
Accounts payable	26,123	1,663
Accrued and other expenses	7,576	2,430
Deferred revenue	0	1,615
Income taxes payable		7,058
Current portion of equipment financing obligations	572	674
Current portion of notes payable	288	282
Total current assets	34,559	13,722
Equipment financing obligations, net of current portion		572
Notes payable, net of current portion		288
Deferred tax liabilities, long-term, net	13,239	15,044
Asset retirement obligation	8,982	1,384
Total liabilities	56,780	31,010
Commitments and contingencies (Note 21)
Stockholders’ equity
Common stock, $0.001 par value, 350,000,000 shares authorized; 40,474,085 issued and 40,393,033 outstanding at December 31, 2017; 38,884,068 issued and 38,816,474 outstanding at December 31, 2016	40	39
Treasury stock, at cost, 81,052 shares and 67,594 shares at December 31, 2017 and 2016, respectively	(666)	(539)
Additional paid-in capital	159,059	132,879
Retained earnings	31,589	10,063
Total stockholders’ equity	190,022	142,442
Total liabilities and stockholders’ equity	$ 246,802	$ 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
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- 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.