Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 154,880	$ 172,960
Short-term investments	334,386	282,437
Accounts receivable, net	54,341	52,704
Inventories	131,499	127,500
Other current assets	29,679	19,605
Total current assets	704,785	655,206
Property and equipment, net	236,807	228,315
Long-term investments	3,057	3,138
Goodwill	6,571	6,571
Deferred tax assets, net	13,821	17,193
Other long-term assets	42,463	45,952
Total assets	1,007,504	956,375
Current liabilities:
Accounts payable	37,752	27,271
Accrued compensation and related benefits	18,633	26,164
Other accrued liabilities	56,110	44,790
Total current liabilities	112,495	98,225
Income tax liabilities	37,596	37,596
Other long-term liabilities	44,223	47,063
Total liabilities	194,314	182,884
Commitments and contingencies
Stockholders’ equity:
Common stock and additional paid-in capital: $0.001 par value; shares authorized: 150,000; shares issued and outstanding: 44,715 and 43,616, respectively	581,736	549,517
Retained earnings	241,465	229,450
Accumulated other comprehensive loss	(10,011)	(5,476)
Total stockholders’ equity	813,190	773,491
Total liabilities and stockholders’ equity	$ 1,007,504	$ 956,375