CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Dec. 29, 2012	Dec. 31, 2011
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 2,718	$ 3,476
Non-cash adjustments to net income:
Depreciation and amortization	1,011	1,463
Provision for doubtful accounts and sales returns	211	8
Provision for excess and obsolete inventories	1,530	2,946
Deferred income taxes	(126)	(99)
Stock-based compensation	2,162	2,243
Tax benefit related to stock-based compensation plans	7	6
Unrealized loss (gain) from short-term investments, categorized as trading	(285)	312
Amortization of premium on short-term investments	1,927	2,266
Loss on disposal of property, plant and equipment		1
Changes in operating assets and liabilities:
Trade accounts receivable	2,067	1,651
Inventories	1,481	772
Prepaid expenses and other assets	1,466	(2,568)
Prepaid income taxes	(199)	1,088
Trade accounts payable and accrued expenses	1,207	(1,492)
Deferred revenue	(491)	(1,119)
Income taxes payable	(265)	(2,161)
Net cash provided by operating activities	14,421	8,793
CASH FLOWS FROM INVESTING ACTIVITIES
Purchases of property, plant and equipment	(434)	(778)
Purchases of investments	(80,233)	(129,217)
Sales of investments	27,749	67,181
Maturities and redemptions of investments	55,171	61,418
Net cash provided by (used in) investing activities	2,253	(1,396)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from exercise of stock options and employee stock purchase plan	363	1,380
Stock repurchases	(8,530)	(15,897)
Payments of dividends to shareholders	(11,523)
Net cash used in financing activities	(19,690)	(14,517)
NET DECREASE IN CASH AND CASH EQUIVALENTS	(3,016)	(7,120)
CASH AND CASH EQUIVALENTS:
Beginning of period	19,860	23,962
End of period	16,844	16,842
Supplemental cash flow disclosures:
Income taxes paid (refunds received), net	$ (717)	$ 4,600