Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 149,382	$ 148,364
Short-term investments	3,000	2,000
Accounts receivable, net of allowances of $1,994 and $2,066, respectively	21,578	24,487
Inventories	18,055	18,719
Prepaid expenses and other current assets	2,828	3,103
Total current assets	194,843	196,673
Property and equipment, net	11,382	11,013
Indefinite-lived intangibles	3,100	3,100
Goodwill	2,486	2,486
Other assets	509	535
Total assets	212,320	213,807
Current liabilities:
Accounts payable	5,793	7,073
Accrued liabilities	9,266	13,974
Total current liabilities	15,059	21,047
Other long-term liabilities	3,508	3,561
Total liabilities	18,567	24,608
Stockholders' equity:
Preferred stock, $0.001 par value; 5,000 shares authorized; none issued and outstanding
Common stock, $0.001 par value; 200,000 shares authorized; 28,859 and 28,793 shares issued, respectively 25,090 and 25,152 shares outstanding, respectively	29	29
Additional paid-in capital	177,449	174,056
Retained earnings	69,089	66,053
Treasury stock at cost, 3,769 and 3,641 shares, respectively	(52,814)	(50,939)
Total stockholders' equity	193,753	189,199
Total liabilities and stockholders' equity	$ 212,320	$ 213,807