Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Current assets
Cash and cash equivalents	$ 43,039	$ 36,759
Short-term marketable securities	36,339	25,137
Accounts receivable, net of allowance for doubtful accounts of $90 and $154 as of December 31, 2013 and December 31, 2012, respectively	18,320	15,791
Inventory	5,166	4,619
Prepaid expenses and other current assets	3,569	5,364
Income taxes receivable	2,907	1,877
Deferred tax assets	455	609
Total current assets	109,795	90,156
Property and equipment, net	56,101	45,316
Long-term marketable securities	64,023	36,965
Other long-term assets	256	285
Total assets	230,175	172,722
Current liabilities
Accounts payable	6,455	4,758
Accrued compensation	6,196	5,995
Accrued liabilities and other	808	513
Current portion of long-term debt obligations	204	273
Total current liabilities	13,663	11,539
Long-term deferred tax liabilities	3,682	3,346
Long-term debt obligations	159	356
Other long-term liabilities	1,028	782
Total liabilities	18,532	16,023
Shareholders' equity
Preferred stock, $0.001 par value, authorized 10,000,000 shares; issued and outstanding 0 shares as of December 31, 2013 and December 31, 2012, respectively
Common stock, $0.001 par value, authorized 150,000,000 shares; issued and outstanding 25,546,107 and 24,803,640 shares as of December 31, 2013 and December 31, 2012, respectively	26	25
Additional paid in capital	166,861	147,032
Retained earnings	45,847	10,570
Accumulated other comprehensive income (loss)	(1,091)	(928)
Total shareholders' equity	211,643	156,699
Total liabilities and shareholders' equity	$ 230,175	$ 172,722