Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 82,759	$ 112,703
Short-term investments	216,331	155,521
Accounts receivable, net	38,037	34,248
Inventories	99,281	71,469
Other current assets	12,762	9,043
Total current assets	449,170	382,984
Property and equipment, net	144,636	85,171
Long-term investments	5,256	5,354
Goodwill	6,571	6,571
Acquisition-related intangible assets, net	951	3,002
Deferred tax assets, net	15,917	633
Other long-term assets	30,068	27,411
Total assets	652,569	511,126
Current liabilities:
Accounts payable	22,813	17,427
Accrued compensation and related benefits	15,597	12,578
Accrued liabilities	27,507	22,916
Total current liabilities	65,917	52,921
Income tax liabilities	31,621	3,870
Other long-term liabilities	33,024	23,219
Total liabilities	130,562	80,010
Commitments and contingencies (notes 12, 13 and 14)
Stockholders' equity:
Common stock and additional paid-in capital, $0.001 par value; shares authorized: 150,000; shares issued and outstanding: 41,614 and 40,793 as of December 31, 2017 and December 31, 2016, respectively	376,586	315,969
Retained earnings	143,608	119,362
Accumulated other comprehensive income (loss)	1,813	(4,215)
Total stockholders’ equity	522,007	431,116
Total liabilities and stockholders’ equity	$ 652,569	$ 511,126