CONSOLIDATED STATEMENTS OF NET INCOME - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Apr. 30, 2017	Jan. 29, 2017	Oct. 30, 2016	Jul. 31, 2016	May 01, 2016	Jan. 31, 2016	Nov. 01, 2015	Aug. 02, 2015	Apr. 30, 2017	May 01, 2016	May 03, 2015
Income Statement [Abstract]
net sales	$ 77,350	$ 76,169	$ 75,343	$ 80,682	$ 77,253	$ 78,466	$ 76,956	$ 80,185	$ 309,544	$ 312,860	$ 310,166
cost of sales	60,194	59,410	58,442	62,263	60,640	61,903	61,223	63,983	240,309	247,749	254,599
gross profit	17,156	16,759	16,901	18,419	16,613	16,563	15,733	16,202	69,235	65,111	55,567
selling, general and administrative expenses	9,986	9,824	9,602	9,746	9,261	9,337	9,433	8,741	39,157	36,773	32,778
income from operations	7,170	6,935	7,299	8,673	7,352	7,226	6,300	7,461	30,078	28,338	22,789
interest expense								24			64
interest income	(134)	(124)	(15)	(25)	(26)	(38)	(69)	(66)	(299)	(176)	(622)
other expense	305	69	155	152	211	85	225	95	681	616	391
income before income taxes	6,999	6,990	7,159	8,546	7,167	7,179	6,144	7,408	29,696	27,898	22,956
income tax expense (note 9)	778	643	2,684	3,233	3,566	2,317	2,373	2,707	7,339	10,963	7,885
loss from investment in unconsolidated joint venture (note 6)	23								23
net income	$ 6,198	$ 6,347	$ 4,475	$ 5,313	$ 3,601	$ 4,862	$ 3,771	$ 4,701	$ 22,334	$ 16,935	$ 15,071
net income per share-basic	$ 0.50	$ 0.52	$ 0.36	$ 0.43	$ 0.29	$ 0.39	$ 0.31	$ 0.38	$ 1.81	$ 1.38	$ 1.23
net income per share-diluted	$ 0.49	$ 0.51	$ 0.36	$ 0.43	$ 0.29	$ 0.39	$ 0.30	$ 0.38	$ 1.78	$ 1.36	$ 1.21

Total costs related to goods produced and sold during the reporting period.

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