Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net income (loss)	$ 32,277	$ (9,372)	$ (6,607)
Adjustments to reconcile net loss to net cash provided by operating activities
Depreciation and amortization expense	7,926	6,402	8,273
Stock-based compensation expense	29,992	16,009	1,379
Inventory write-down	1,817	1,446	321
Impairment of internal-use software	0	959
Other	117	106	9
Changes in assets and liabilities:
Accounts receivable	14,456	6,261	(1,521)
Related party accounts receivable	736	337	363
Inventories	(13,096)	(2,070)	8,144
Prepaid expenses and other assets	(1,859)	2,951	(3,145)
Accounts payable	5,826	2,606	(1,148)
Accrued expenses and other liabilities	9,798	3,491	(1,732)
Net cash provided by operating activities	59,078	16,604	7,378
Cash flows from investing activities
Purchase of property and equipment	(30,878)	(6,098)	(1,426)
Cash paid for intangibles	(2,910)	(1,695)	(1,776)
Net cash used in investing activities	(33,788)	(7,793)	(3,202)
Cash flows from financing activities
Proceeds from public offering, net of underwriting discounts and commissions and other offering costs	460,646	45,789	56,353
Tax withholding paid on behalf of employees for net share settlement	0	(3,493)	0
Proceeds from loans from financial institutions	0	35,000	0
Principal payments on loans to financial institutions	0	(76,000)	(2,000)
Principal payments on loan to MegaChips	0	0	(3,000)
Net cash provided by financing activities	460,646	1,296	51,353
Net increase in cash and cash equivalents	485,936	10,107	55,529
Cash and cash equivalents
Beginning of period	73,525	63,418	7,889
End of period	559,461	73,525	63,418
Supplemental disclosure of cash flow information
Interest paid during the period	0	799	2,167
Income taxes paid	24	1	1
Supplemental disclosure of noncash flow information
Unpaid property and equipment	1,437	343	77
Unpaid intangibles, net	3,178	0	0
Right-of-use assets acquired under operating leases	$ 689	$ 382	$ 10,763