Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 156,483	$ 172,960
Short-term investments	355,840	282,437
Accounts receivable, net	55,136	52,704
Inventories	152,119	127,500
Other current assets	29,286	19,605
Total current assets	748,864	655,206
Property and equipment, net	251,980	228,315
Long-term investments	3,032	3,138
Goodwill	6,571	6,571
Deferred tax assets, net	13,432	17,193
Other long-term assets	47,276	45,952
Total assets	1,071,155	956,375
Current liabilities:
Accounts payable	45,169	27,271
Accrued compensation and related benefits	32,785	26,164
Other accrued liabilities	58,831	44,790
Total current liabilities	136,785	98,225
Income tax liabilities	35,624	37,596
Other long-term liabilities	49,801	47,063
Total liabilities	222,210	182,884
Stockholders’ equity:
Common stock and additional paid-in capital: $0.001 par value; shares authorized: 150,000; shares issued and outstanding: 44,911 and 43,616, respectively	605,165	549,517
Retained earnings	247,864	229,450
Accumulated other comprehensive loss	(4,084)	(5,476)
Total stockholders’ equity	848,945	773,491
Total liabilities and stockholders’ equity	$ 1,071,155	$ 956,375