Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 20,486	$ 17,095
Marketable securities	23,181	47,051
Accounts receivable	438	200
Prepaid expenses and other current assets	716	1,329
Total current assets	44,821	65,675
Prepaid expenses, long-term	230	408
Property, plant and equipment, net (note 6)	1,070	1,404
Total assets	46,121	67,487
Current liabilities:
Accounts payable and accrued expenses (note 7)	3,383	3,586
Loan payable, current portion (note 8)	700
Total current liabilities	4,083	3,586
Loan payable, long-term (note 8)	6,104
Total liabilities	10,187	3,586
Shareholders’ equity:
Common shares, without par value; unlimited shares authorized; issued and outstanding: 17,998,420 (December 31, 2016 - 17,930,590) (note 9b)	173,841	173,246
Additional paid-in capital	36,471	34,326
Accumulated deficit	(173,388)	(142,681)
Accumulated other comprehensive loss	(990)	(990)
Shareholders' equity	35,934	63,901
Total liabilities and shareholders’ equity	46,121	67,487
Commitments and contingencies (note 12)

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits.

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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.