CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accounts payable	$ 17,643	$ 12,941
Advance from customers	21,731	17,732
Accrued expenses and other current liabilities	$ 28,642	$ 22,688
Ordinary shares, par value (in dollars per share)	$ 0.000067	$ 0.000067
Ordinary shares, shares authorized	750,000,000	750,000,000
Ordinary shares, shares issued	203,349,887	150,011,929
Ordinary shares, shares outstanding	187,214,651	134,456,369
Treasury stock, shares	14,011,790	13,525,810
Consolidated VIEs
Accounts payable	$ 135	$ 5
Accrued expenses and other current liabilities	$ 1,012	$ 4,673

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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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. 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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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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