Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 75,104	$ 96,371
Short-term investments	85,521	77,827
Accounts receivable, net of allowances of $20 in 2012 and $5 in 2011	19,383	15,097
Inventories	32,115	20,104
Deferred income tax assets, net - current	1	421
Prepaid expenses and other current assets	2,177	1,685
Total current assets	214,301	211,505
Property and equipment, net	59,412	47,794
Long-term investments	11,755	13,675
Deferred income tax assets, net - long-term	669	239
Other assets	1,025	654
Total assets	287,162	273,867
Current liabilities:
Accounts payable	9,859	8,904
Accrued compensation and related benefits	7,686	9,321
Accrued liabilities	5,915	7,845
Total current liabilities	23,460	26,070
Non-current income tax liabilities	5,408	4,920
Total liabilities	28,868	30,990
Commitments and contingencies (Note 9)
Stockholders' equity:
Common stock, $0.001 par value; shares authorized: 150,000,000; shares issued and outstanding: 35,673,282 and 33,826,032 in 2012 and 2011, respectively	194,079	159,336
Retained earnings	60,040	79,948
Accumulated other comprehensive income	4,175	3,593
Total stockholders’ equity	258,294	242,877
Total liabilities and stockholders’ equity	$ 287,162	$ 273,867