Commitments (Details Textual) (USD $)	3 Months Ended		6 Months Ended
	Sep. 29, 2012	Oct. 01, 2011	Sep. 29, 2012	Oct. 01, 2011
Commitments (Textual) [Abstract]
Aggregate future rental income to be received	$ 5,100,000		$ 5,100,000
Rent expense, net of rental income	1,300,000	521,000	2,100,000	1,600,000
Other commitments	119,300,000		119,300,000
Non-cancelable license obligations	19,600,000		19,600,000
Maximum future commitment to acquire licenses to intellectual property until July 2023	$ 5,000,000