Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Current assets
Cash and cash equivalents	$ 56,324	$ 43,329
Short-term marketable securities	31,190	30,706
Accounts receivable, net of allowance for doubtful accounts of $150 and $198 as of June 30, 2015 and December 31, 2014, respectively	29,493	24,226
Inventory	6,828	6,194
Prepaid expenses and other current assets	3,935	$ 3,406
Income taxes receivable	2,931
Deferred tax assets	464	$ 483
Total current assets	131,165	108,344
Property and equipment, net	100,921	91,626
Goodwill	28,916	28,916
Other intangible assets, net	3,710	4,083
Long-term marketable securities	54,482	54,318
Other long-term assets	197	227
Total assets	319,391	287,514
Current liabilities
Accounts payable	11,334	7,882
Accrued compensation	8,264	6,067
Accrued liabilities and other	$ 1,779	2,718
Income taxes payable		1,953
Current portion of long-term debt obligations	$ 71	139
Total current liabilities	21,448	18,759
Long-term deferred tax liabilities	$ 2,423	1,846
Long-term debt obligations		10
Other long-term liabilities	$ 1,533	1,360
Total liabilities	$ 25,404	$ 21,975
Shareholders' equity
Preferred stock, $0.001 par value, authorized 10,000,000 shares; issued and outstanding 0 shares as of each of June 30, 2015 and December 31, 2014
Common stock, $0.001 par value, authorized 150,000,000 shares; issued and outstanding 25,953,735 and 25,838,110 shares as of June 30, 2015 and December 31, 2014, respectively	$ 26	$ 26
Additional paid-in capital	187,070	180,960
Retained earnings	109,621	87,482
Accumulated other comprehensive loss	(2,730)	(2,929)
Total shareholders' equity	293,987	265,539
Total liabilities and shareholders' equity	$ 319,391	$ 287,514