Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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The price per share of the conversion feature embedded in the debt instrument.

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The cash inflow from a borrowing supported by a written promise to pay an obligation.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Number of shares of stock issued during the period pursuant to acquisitions.

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Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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Subsequent events (Additional Information) (Details) $ / shares in Units, $ in Thousands, $ in Millions				1 Months Ended
	Apr. 10, 2018 USD ($) $ / shares shares	Jan. 05, 2017 shares	Mar. 15, 2016 shares	Apr. 18, 2018 USD ($) $ / shares	Feb. 22, 2018 USD ($) shares	Feb. 22, 2018 HKD ($) shares	Apr. 28, 2017 shares	Dec. 31, 2017
Subsequent Event [Line Items]
Ordinary shares issued to employees, directors and consultants		190,000
Stock Issued During Period, Shares, Acquisitions			1,162,305				1,500,000
Debt Instrument, Interest Rate, Stated Percentage								5.00%
Subsequent Events [Member]
Subsequent Event [Line Items]
Ordinary shares issued to employees, directors and consultants	180,000
Grant date fair value for ordinary shares issued to independent directors and certain employees \| $ / shares	$ 1.08
Compensation expense \| $	$ 194
Debt Instrument, Term				5 years
Proceeds from Notes Payable \| $				$ 5,779,602
Debt Instrument, Interest Rate, Stated Percentage				2.50%
Debt Instrument, Convertible, Conversion Price \| $ / shares				$ 1.50
Subsequent Events [Member] \| Hau Fook Street Limited [Member]
Subsequent Event [Line Items]
Business Combination, Consideration Transferred					$ 3,300	$ 26.1
Stock Issued During Period, Shares, Acquisitions					2,935,223	2,935,223