Income Per Share (Schedule of Earnings Per Share, Basic and Diluted) (Details) (USD $)	3 Months Ended																12 Months Ended
	Apr. 26, 2013		Jan. 25, 2013		Oct. 26, 2012		Jul. 27, 2012		Apr. 27, 2012		Jan. 27, 2012		Oct. 28, 2011		Jul. 29, 2011		Apr. 26, 2013		Apr. 27, 2012		Apr. 29, 2011
Income Per Share [Abstract]
Net income	$ 11,532,071		$ 13,183,494		$ 13,566,904		$ 8,075,033		$ 10,663,220		$ 9,502,184		$ 9,027,774		$ 6,884,554		$ 46,357,502		$ 36,077,732		$ 46,725,710
Add effect of Convertible Notes																	0	[1]	97,486	[1]	112,061	[1]
Diluted income																	$ 46,357,502		$ 36,175,218		$ 46,837,771
Basic weighted average shares outstanding (in Shares)																	27,604,006		27,826,586		28,050,638
Stock Options																	404,954		367,671		382,596
Convertible Notes (in Shares)																	0	[1]	112,475	[1]	176,385	[1]
Diluted weighted average shares outstanding (in Shares)																	28,008,960		28,306,732		28,609,619
Basic income per share (in Dollars per Share)																	$ 1.68		$ 1.30		$ 1.67
Diluted income per share (in Dollars per Share)	$ 0.41	[2]	$ 0.47	[2]	$ 0.48	[2]	$ 0.29	[2]	$ 0.38	[2]	$ 0.34	[2]	$ 0.32	[2]	$ 0.24	[2]	$ 1.66	[2]	$ 1.28	[2]	$ 1.64

[1] We determine the dilutive effect of any retired or repurchased Convertible Notes separately from the dilutive effect of Convertible Notes outstanding at period end.

[2] EPS in each quarter is computed using the weighted-average number of shares outstanding during that quarter while EPS for the full year is computed using the weighted-average number of shares outstanding during the year. Thus, the sum for the four quarters’ EPS does not necessarily equal the full year EPS