Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 197,012	$ 172,704
Short-term investments	169,459	204,577
Accounts receivable, net	55,398	55,214
Inventories	143,622	136,384
Other current assets	19,645	11,931
Total current assets	585,136	580,810
Property and equipment, net	213,830	150,001
Long-term investments	3,215	3,241
Goodwill	6,571	6,571
Deferred tax assets, net	16,686	16,830
Other long-term assets	42,675	35,979
Total assets	868,113	793,432
Current liabilities:
Accounts payable	26,544	22,678
Accrued compensation and related benefits	22,960	18,799
Other accrued liabilities	38,616	38,962
Total current liabilities	88,120	80,439
Income tax liabilities	32,402	34,375
Other long-term liabilities	43,437	38,525
Total liabilities	163,959	153,339
Commitments and contingencies
Stockholders' equity:
Common stock and additional paid-in capital: $0.001 par value; shares authorized: 150,000; shares issued and outstanding: 43,234 and 42,505, respectively	503,759	450,908
Retained earnings	204,533	194,728
Accumulated other comprehensive loss	(4,138)	(5,543)
Total stockholders’ equity	704,154	640,093
Total liabilities and stockholders’ equity	$ 868,113	$ 793,432