Income Taxes (Significant Components of Deferred Tax Assets) (Details) (USD $)	Apr. 26, 2013	Apr. 27, 2012
Deferred tax assets (liabilities):
Federal net operating loss carryforwards	$ 11,652,605	$ 36,967,643
Foreign net operating loss carryforwards	12,309,347	12,957,928
State net operating loss carryforwards	882,678	1,785,714
Tax credit carryforwards	7,084,538	4,780,962
Deferred compensation	6,119,515	7,877,434
Accruals and reserves	2,102,427	2,213,570
Licensing income and expense	776,467	1,214,115
Property and Equipment	(789,106)	(145,692)
Other	4,166,569	1,460,454
Total deferred tax assets	44,305,040	69,112,128
Deferred tax valuation allowance	(26,181,763)	(37,852,345)
Net deferred tax assets	$ 18,123,277	$ 31,259,783