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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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(a))
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Concentration of risks (Additional Information) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Concentration Risk [Line Items]
Accounts receivable, net of provision for doubtful accounts of $1 and nil, respectively		$ 119
Accounts payable, trade	$ 235	222
Major Customer One [Member]
Concentration Risk [Line Items]
Concentration risk percentage	66.70%
Major Customer Two [Member]
Concentration Risk [Line Items]
Concentration risk percentage	18.30%
Major Customer One Two And Three [Member]
Concentration Risk [Line Items]
Accounts receivable, net of provision for doubtful accounts of $1 and nil, respectively			$ 228
Sales Revenue [Member] \| Major Vendor One And Two [Member]
Concentration Risk [Line Items]
Revenues	$ 40
Concentration risk percentage	85.00%
Sales Revenue [Member] \| Major Customer One [Member]
Concentration Risk [Line Items]
Concentration risk percentage			39.60%
Sales Revenue [Member] \| Major Customer Two [Member]
Concentration Risk [Line Items]
Concentration risk percentage			16.20%
Sales Revenue [Member] \| Major Customer Three [Member]
Concentration Risk [Line Items]
Concentration risk percentage			11.00%
Sales Revenue [Member] \| Major Customer One Two And Three [Member]
Concentration Risk [Line Items]
Revenues			$ 1,244
Concentration risk percentage			66.80%
Sales Revenue [Member] \| Major Customer [Member]
Concentration Risk [Line Items]
Revenues		$ 4,315
Concentration risk percentage		85.10%
Accounts Payable [Member] \| Major Vendor One And Two [Member]
Concentration Risk [Line Items]
Concentration risk percentage		86.10%
Accounts Payable [Member] \| Major Vendor One, Two and Three [Member]
Concentration Risk [Line Items]
Concentration risk percentage	90.60%		83.40%
Accounts payable, trade			$ 46
Accounts Receivable [Member] \| Major Customer [Member]
Concentration Risk [Line Items]
Accounts receivable, net of provision for doubtful accounts of $1 and nil, respectively		$ 119
Honesty Group [Member] \| Accounts Payable [Member] \| Major Vendor One, Two and Three [Member]
Concentration Risk [Line Items]
Concentration risk percentage			15.60%