Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 29, 2013	Jun. 30, 2012
Cash flows from operating activities:
Net income (loss)	$ (10,148)	$ 6,209
Reconciliation of net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization	4,268	3,857
Stock-based compensation	3,208	3,054
Excess tax benefit from equity awards	367	(814)
Loss on disposal of fixed assets	10	134
Inventory write down	2,764	1,740
Deferred income taxes	(6,657)	995
Changes in fair value of contingent consideration	1,000	9
Changes in assets and liabilities:
Accounts receivable	(11,095)	(11,141)
Inventories	(4,121)	(1,475)
Inventories-delivered systems	(170)	(229)
Prepaid expenses and other	(109)	(1,798)
Accounts payable, accrued and other liabilities	1,566	(3,060)
Deferred revenue	2,548	4,222
Income taxes payable	(389)	466
Net cash provided by (used in) operating activities	(16,958)	2,169
Cash flows from investing activities:
Maturities of marketable securities	22,788	0
Escrow payment received related to Nanda acquisition	0	508
Purchases of marketable securities	(23,454)	(13,764)
Purchases of property, plant and equipment	(1,970)	(2,635)
Net cash used in investing activities	(2,636)	(15,891)
Cash flows from financing activities:
Payments of contingent consideration	(216)	(198)
Repayments of debt obligations	(456)	(374)
Proceeds from sale of shares under employee stock option plans and purchase plan	2,858	2,632
Excess tax benefit from equity awards	(367)	814
Taxes paid on net issuance of stock awards	(86)	(16)
Repurchases of common stock	(5,000)	(4,960)
Net cash used in financing activities	(3,267)	(2,102)
Effect of exchange rate changes on cash and cash equivalents	(952)	115
Net decrease in cash and cash equivalents	(23,813)	(15,709)
Cash and cash equivalents, beginning of period	62,915	97,699
Cash and cash equivalents, end of period	$ 39,102	$ 81,990