Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 223,121	$ 384,557
Short-term investments	362,747	192,234
Restricted cash	2,061	2,017
Accounts receivable, net	42,912	63,169
Inventories	67,689	59,807
Prepaid expenses and other current assets	30,582	32,155
Deferred income taxes	13,171	10,545
Total current assets	742,283	744,484
Property, plant and equipment at cost, net	96,714	98,302
Goodwill	55,828	55,828
Deferred income taxes	4,505	935
Intangible assets, net	20,118	20,974
Other assets	16,435	16,781
Total assets	935,883	937,304
Current liabilities:
Accounts payable	32,503	26,087
Accrued expenses and other current liabilities	76,132	74,260
Deferred revenue	9,216	9,380
Income taxes payable	697	2,292
Current portion of long-term debt	274	268
Total current liabilities	118,822	112,287
Deferred income taxes	7,137	7,137
Long-term debt	2,067	2,138
Other liabilities	4,737	4,530
Total liabilities	132,763	126,092
Equity:
Preferred stock, 500,000 shares authorized; no shares issued and outstanding
Common stock; $.01 par value; authorized 120,000,000 shares; 39,304,294 and 39,328,503 shares issued and outstanding in 2013 and 2012, respectively	393	393
Additional paid-in capital	711,481	708,723
Retained earnings	86,052	96,123
Accumulated other comprehensive income	5,194	5,973
Total equity	803,120	811,212
Total liabilities and equity	$ 935,883	$ 937,304