CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Dec. 31, 2011	Jan. 01, 2011
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 3,476	$ 10,790
Non-cash adjustments to net income:
Depreciation and amortization	1,463	1,718
Provision for doubtful accounts and sales returns	8	467
Provision for excess and obsolete inventories	2,946	694
Deferred income taxes	(99)	734
Stock-based compensation	2,243	2,372
Tax benefit related to stock-based compensation plans	6	106
Excess tax benefit related to stock-based compensation	0	(5)
Unrealized loss (gain) from short-term investments, categorized as trading	312	(457)
Amortization of premium on short-term investments	2,266	1,554
Loss on disposal of property, plant and equipment	1	1
Changes in operating assets and liabilities:
Trade accounts receivable	1,651	(342)
Inventories	772	(5,308)
Prepaid expenses and other assets	(2,568)	111
Prepaid income taxes	1,088	(1,780)
Trade accounts payable and accrued expenses	(1,492)	829
Deferred revenue	(1,119)	(137)
Income taxes payable	(2,161)	2,790
Net cash provided by operating activities	8,793	14,137
CASH FLOWS FROM INVESTING ACTIVITIES
Purchases of property, plant and equipment	(778)	(876)
Purchases of investments	(129,217)	(99,261)
Sales of investments	67,181	17,374
Maturities and redemptions of investments	61,418	80,945
Net cash used in investing activities	(1,396)	(1,818)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from exercise of stock options and employee stock purchase plan	1,380	2,277
Stock repurchases	(15,897)	0
Excess tax benefit related to stock-based compensation	0	5
Net cash (used in) provided by financing activities	(14,517)	2,282
NET (DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS	(7,120)	14,601
CASH AND CASH EQUIVALENTS:
Beginning of period	23,962	10,153
End of period	16,842	24,754
Supplemental cash flow disclosures:
Income taxes paid, net of refunds	$ 4,600	$ 2,092