Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities:
Net income	$ 12,479	$ 15,257
Adjustments to reconcile net income from operations to net cash used in operating activities:
Depreciation and amortization	774	586
Loss on disposals of property, plant and equipment	1	296
Equity income in net income of affiliates	(539)	(260)
Unrealized gain on trading securities	(8,970)	0
Deferred income taxes	(4,632)	(757)
Stock-based compensation	4,323	2,919
Change in fair value of financial liability	11,964	0
Net changes in operating assets and liabilities:
Accounts receivable	(27,575)	(19,634)
Other receivables	(3,512)	1,187
Inventory	(18,362)	(5,889)
Prepaid expenses	(3,371)	323
Other long-term assets	(839)	(182)
Accounts payable	22,023	(417)
Advances from customers	(1,142)	746
Income tax payable	389	162
Other payables and accrued expenses	5,962	2,352
Deferred revenue	819	0
Other long-term liabilities	2,172	(1,441)
Net cash flow used in operating activities	(8,036)	(4,752)
Cash flows from investing activities:
Purchase of property and equipment	(3,583)	(832)
Purchase of intangible assets	(81)	(114)
Purchase of land-use-right	(9,331)	0
Purchase of trading securities	(14,680)	0
Prepayment for property	(6,978)	0
Investments in unconsolidated affiliates	0	(4,348)
Net cash used in investing activities	(34,653)	(5,294)
Cash flows from financing activities:
Proceeds from short-term borrowings	31,068	18,267
Repayments of short-term borrowings	(16,881)	(11,770)
Repayments of notes payable	(1,820)	0
Proceeds from stock option exercise to common stock	2,191	312
Proceeds from issuance of Class A common stock in connection with public offering, net of direct issuance expenses of $2,287	0	26,463
Payment for repurchase of Class A common stock	0	(785)
Payment for cancellation of stock option	0	(576)
Proceeds from issuance of common stock to redeemable Non-controlling interest	0	27,264
Net cash provided by financing activities	14,558	59,175
Effect of exchange rate changes on cash, cash equivalents and restricted cash	2,475	(2,407)
Net increase (decrease) in cash, cash equivalents and restricted cash	(25,656)	46,722
Cash, cash equivalents and restricted cash at beginning of period	117,859	27,124
Cash, cash equivalents and restricted cash at end of period	92,203	73,846
Supplemental disclosure of cash flow information:
Interest paid	611	538
Cash paid for income taxes	4,606	0
Reconciliation of cash, cash equivalents and restricted cash in condensed consolidated statements of cash flows:
Cash and cash equivalents	92,203	47,264
Restricted cash	0	26,582
Non-cash financing activities:
Warrant conversion to common stock	399	0
Share cancellation, note 12	9,715	0
Issuance of warrant for settlement of financial liability and cancellation of note receivable	$ 19,859	$ 0