CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Sep. 27, 2014	Sep. 28, 2013
CASH FLOWS FROM OPERATING ACTIVITIES
Net (loss) income	$ (14,494)	$ (6,061)
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation, Depletion and Amortization	3,909	3,521
Amortization of acquired intangible assets	857	1,546
Share-based compensation expense	2,363	3,868
Loss on sale of property and equipment, net	56	(37)
Business Combination, Bargain Purchase, Gain Recognized, Amount	0	(499)
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	0	3,588
Decrease (increase) in deferred income taxes	(170)	(126)
Changes in operating accounts, net of acquisitions:
Decrease (increase) in trade receivables, net	(2,085)	1,101
Decrease (increase) in inventories	2,851	(170)
Decrease (increase) in shipped systems pending acceptance	(3,126)	458
Decrease in other current assets	679	(801)
Increase (decrease) in accounts payable and accrued liabilities	245	(7,051)
(Decrease) increase in deferred revenue	5,925	(2,520)
Net cash provided by operating activities	(3,102)	(3,109)
CASH FLOWS FROM INVESTING ACTIVITIES
Purchase of investments	(279,918)	(193,421)
Proceeds from sales and maturities of investments	303,793	201,615
Purchase of property, plant and equipment	(2,365)	(2,279)
Proceeds from Sale of Property, Plant, and Equipment	154
Cash paid to acquire subsidiaries	0	(9,731)
Payments to Acquire Other Investments	0	(5,000)
Decrease (increase) in other assets	(857)	(67)
Net cash provided by (used in) investing activities	20,807	(8,883)
CASH FLOWS FROM FINANCING ACTIVITIES
Cash dividends paid to shareholders	(4,834)	(4,765)
Stock plan activity, net	(262)	(430)
Payments for Repurchase of Common Stock	(1,456)
Net cash (used in) provided by financing activities	(6,552)	(5,195)
Effect of exchange rate changes on cash	(359)	249
NET CHANGE IN CASH AND CASH EQUIVALENTS	10,794	(16,938)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	68,461	88,913
CASH AND CASH EQUIVALENTS AT END OF PERIOD	79,255	71,975
SUPPLEMENTAL CASH FLOW INFORMATION
Cash paid for interest	(2)	0
Cash paid for income taxes	(489)	(2,540)
Income tax refunds received	$ 557	$ 19