Allowance for Credit Losses (Details) (USD $)	12 Months Ended
	Apr. 27, 2013	Apr. 28, 2012
Allowance for Credit Losses [Abstract]
Notes receivable, gross	$ 8,300,000	$ 10,300,000
Number of customers with notes receivable balance	9	12
Allowance for credit losses	1,986,000	1,537,000
Notes receivable, current	1,800,000	1,900,000
Allowance for Credit Losses [Roll Forward]
Ending balance	1,986,000	1,537,000
Allowance for Credit Losses [Member]
Allowance for Credit Losses [Abstract]
Allowance for credit losses	1,986,000	1,537,000
Allowance for Credit Losses [Roll Forward]
Beginning balance	1,537,000	2,067,000
Recoveries	(73,000)	(38,000)
Write-offs	0	(1,231,000)
Provision for credit losses, net	522,000	825,000
Currency effect	0	(86,000)
Ending balance	$ 1,986,000	$ 1,537,000