Net Sales by Geographic Area (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 30, 2012	Oct. 02, 2011	Sep. 30, 2012	Oct. 02, 2011
Operating Statistics [Line Items]
Total net sales	$ 30,622	$ 36,120	$ 59,873	$ 73,098
United States [Member]
Operating Statistics [Line Items]
Total net sales	8,083	9,372	14,276	18,491
China [Member]
Operating Statistics [Line Items]
Total net sales	10,720	12,757	20,709	25,308
Singapore [Member]
Operating Statistics [Line Items]
Total net sales	3,280	3,607	7,316	7,495
Germany [Member]
Operating Statistics [Line Items]
Total net sales	3,165	3,257	6,203	7,710
Europe (excluding Germany) [Member]
Operating Statistics [Line Items]
Total net sales	1,438	1,675	2,543	3,347
Japan [Member]
Operating Statistics [Line Items]
Total net sales	1,387	1,796	2,868	3,040
Rest of world [Member]
Operating Statistics [Line Items]
Total net sales	$ 2,549	$ 3,656	$ 5,958	$ 7,707