Note 12 - Quarterly Financial Data (Unaudited) (Details) - Quarterly Financial Data (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Apr. 27, 2013	Jan. 26, 2013	Oct. 27, 2012	Jul. 28, 2012	Apr. 28, 2012	Jan. 28, 2012	Oct. 29, 2011	Jul. 30, 2011	Apr. 27, 2013	Apr. 28, 2012	Apr. 30, 2011
Quarterly Financial Data [Abstract]
Net sales	$ 167,867	$ 144,723	$ 166,568	$ 182,849	$ 165,431	$ 136,401	$ 157,974	$ 169,080	$ 662,007	$ 628,886	$ 600,193
Gross profit	58,013	46,353	54,591	58,293	52,845	45,235	54,103	61,074	217,250	213,257	218,654
Net income	$ 12,097	$ 8,414	$ 12,017	$ 14,392	$ 11,531	$ 7,904	$ 11,123	$ 13,435	$ 46,920	$ 43,993	$ 40,754
Earnings per common share – basic (in Dollars per share)	$ 0.26	$ 0.18	$ 0.26	$ 0.31	$ 0.25	$ 0.17	$ 0.24	$ 0.29	$ 1.01	$ 0.95	$ 0.88
Earnings per common share – diluted (in Dollars per share)	$ 0.26	$ 0.18	$ 0.26	$ 0.31	$ 0.25	$ 0.17	$ 0.24	$ 0.29	$ 1.01	$ 0.95	$ 0.88