Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 29, 2012		Oct. 01, 2011
Cash flows from operating activities:
Net income	$ 33,813		$ 28,059
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation	3,625		3,096
Amortization	214		53
Accretion of asset retirement obligations	87		82
Gain on disposal of equipment	5		(4)
Stock-based compensation	8,379		6,190
Deferred income taxes	0		(17)
Changes in operating assets and liabilities:
Accounts receivable	6,180		(2,065)
Inventories	(6,511)		(11,527)
Prepaid expenses and other current assets	292		(484)
Other assets	(929)		1,297
Accounts payable	4,549		2,496
Deferred product and services income	6,714		(3,453)
Other current liabilities	(6,578)		2,455
Other liabilities	6,123		3,601
Net cash provided by operating activities	55,963		29,779
Cash flows from investing activities:
Capital expenditures	(6,198)		(3,020)
Purchase of patents	(8,000)		0
Purchase of investments in securities	(266,225)		(157,685)
Proceeds from maturities of investments	228,925		120,320
Net cash used in investing activities	(51,498)		(40,385)
Cash flows from financing activities:
Proceeds from notes payable	3,000		10,000
Repayment of notes payable	(3,000)		(12,000)
Proceeds from issuance of common stock for stock option exercises	15,372		12,980
Tax payment for issuance of common stock from release of restricted stock units	(4,312)		(1,268)
Net cash provided by (used in) financing activities	11,060		9,712
Net decrease in cash and cash equivalents	15,525		(894)
Cash and cash equivalents at beginning of period	58,780	[1]	63,626
Cash and cash equivalents at end of period	$ 74,305		$ 62,732

[1] The Balance Sheet as of December 31, 2011 has been derived from the audited financial statements at that date.