CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Sep. 28, 2013	Sep. 29, 2012
CASH FLOWS FROM OPERATING ACTIVITIES
Net (loss) income	$ (6,061)	$ 4,267
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation, Depletion and Amortization	3,521	4,598
Amortization of acquired intangible assets	1,546	1,155
Share-based compensation expense	3,868	4,650
Loss on sale of property and equipment, net	(37)	0
Business Combination, Bargain Purchase, Gain Recognized, Amount	(499)	0
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	3,588	0
Decrease (increase) in deferred income taxes	(126)	2,665
Changes in operating accounts, net of acquisitions:
Decrease (increase) in trade receivables, net	1,101	(25,254)
Decrease (increase) in inventories	(170)	(11,859)
Decrease (increase) in shipped systems pending acceptance	458	1,098
Decrease in other current assets	(801)	130
Increase (decrease) in accounts payable and accrued liabilities	(7,051)	20,107
(Decrease) increase in deferred revenue	(2,520)	(1,407)
Net cash provided by operating activities	(3,109)	150
CASH FLOWS FROM INVESTING ACTIVITIES
Purchase of investments	(193,421)	(559,927)
Proceeds from sales and maturities of investments	201,615	577,733
Purchase of property, plant and equipment	(2,279)	(2,511)
Cash paid to acquire subsidiaries	(9,731)	(9,466)
Payments to Acquire Other Investments	(5,000)	0
Decrease (increase) in other assets	(67)	(63)
Net cash provided by (used in) investing activities	(8,883)	5,766
CASH FLOWS FROM FINANCING ACTIVITIES
Cash dividends paid to shareholders	(4,765)	(4,673)
Stock plan activity, net	(430)	(478)
Excess tax benefit of share-based compensation	0	54
Net cash (used in) provided by financing activities	(5,195)	(5,097)
Effect of exchange rate changes on cash	249	357
NET CHANGE IN CASH AND CASH EQUIVALENTS	(16,938)	1,176
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	88,913	69,780
CASH AND CASH EQUIVALENTS AT END OF PERIOD	71,975	70,956
SUPPLEMENTAL CASH FLOW INFORMATION
Cash paid for interest	0	(550)
Cash paid for income taxes	(2,540)	0
Income tax refunds received	$ 19	$ 650