Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Apr. 05, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 36,047	$ 55,694
Short-term investments	142,343	90,456
Accounts receivable, less reserves of $1,024 and $1,095 in 2015 and 2014, respectively	56,264	50,938
Inventories	48,458	35,536
Deferred income taxes	8,990	8,985
Prepaid expenses and other current assets	17,857	22,997
Total current assets	309,959	264,606
Long-term investments	370,433	400,845
Property, plant, and equipment, net	48,692	47,907
Deferred income taxes	16,349	14,452
Intangible assets, net	9,606	10,699
Goodwill	81,689	81,689
Other assets	1,617	1,536
Total assets	838,345	821,734
Current liabilities:
Accounts payable	13,295	19,114
Accrued expenses	32,240	39,949
Accrued income taxes	928	1,048
Deferred revenue	20,447	20,563
Total current liabilities	66,910	80,674
Reserve for income taxes	4,372	4,623
Commitments and contingencies (Note 7)
Shareholders' equity:
Common stock, $.002 par value – Authorized: 140,000 shares, issued and outstanding: 87,128 and 86,542 shares in 2015 and 2014, respectively	174	173
Additional paid-in capital	272,070	251,717
Retained earnings	544,448	523,946
Accumulated other comprehensive loss, net of tax	(49,629)	(39,399)
Total shareholders’ equity	767,063	736,437
Total liabilities and shareholders' equity	$ 838,345	$ 821,734