Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 7,649	$ 17,192
Marketable securities	4,734	3,200
Receivables, net of allowance for doubtful accounts of $102 and $129, respectively	8,849	9,378
Inventories	12,641	12,278
Deferred income taxes	3,325	3,325
Prepaid expenses and other assets	7,050	2,693
Total current assets	44,248	48,066
Long-term marketable securities	21,645	22,326
Long-term inventories, net	575	551
Property and equipment, net	2,209	1,825
Intangibles, net	6,816	3,710
Goodwill	9,872	3,472
Deferred income taxes	980	1,024
Other assets	91	87
Total assets	86,436	81,061
Current liabilities:
Accounts payable	3,324	2,730
Accrued liabilities	2,627	1,761
Deferred product revenue	4,107	4,158
Total current liabilities	10,058	8,649
Deferred rent	246	286
Other long-term liabilities	2,363	1,791
Total liabilities	12,667	10,726
Shareholders' equity:
Common stock, par value $0.001, 50,000,000 shares authorized, 9,309,529 and 8,986,080 shares issued and outstanding	9	9
Additional paid-in capital	44,182	41,311
Accumulated other comprehensive income	96	23
Retained earnings	29,482	28,992
Total shareholders' equity	73,769	70,335
Total liabilities and shareholders' equity	86,436	81,061
Inventory [Member]
Current assets:
Inventories	11,063	10,758
Distributor Channel Inventory [Member]
Current assets:
Inventories	$ 1,578	$ 1,520