CONSOLIDATED STATEMENTS OF NET INCOME - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Apr. 29, 2018	Jan. 28, 2018	Oct. 29, 2017	Jul. 30, 2017	Apr. 30, 2017	Jan. 29, 2017	Oct. 30, 2016	Jul. 31, 2016	Apr. 29, 2018	Apr. 30, 2017	May 01, 2016
Income Statement [Abstract]
net sales	$ 78,184	$ 85,310	$ 80,698	$ 79,533	$ 77,350	$ 76,169	$ 75,343	$ 80,682	$ 323,725	$ 309,544	$ 312,860
cost of sales	63,424	67,707	64,894	63,068	60,194	59,410	58,442	62,263	259,092	240,309	247,749
gross profit	14,760	17,603	15,804	16,465	17,156	16,759	16,901	18,419	64,633	69,235	65,111
selling, general and administrative expenses	8,296	9,959	9,415	9,501	9,986	9,824	9,602	9,746	37,172	39,157	36,773
income from operations	6,464	7,644	6,389	6,964	7,170	6,935	7,299	8,673	27,461	30,078	28,338
interest expense	26	31	37						94
interest income	(143)	(132)	(128)	(131)	(134)	(124)	(15)	(25)	(534)	(299)	(176)
other expense	115	229	321	353	305	69	155	152	1,018	681	616
income before income taxes	6,466	7,516	6,159	6,742	6,999	6,990	7,159	8,546	26,883	29,696	27,898
income tax expense (note 10)	(6,217)	8,208	2,108	1,640	778	643	2,684	3,233	5,740	7,339	10,963
loss from investment in unconsolidated joint venture (note 7)	17	56	75	118	23				266	23
net income	$ 12,666	$ (748)	$ 3,976	$ 4,984	$ 6,198	$ 6,347	$ 4,475	$ 5,313	$ 20,877	$ 22,334	$ 16,935
net income per share-basic	$ 1.02	$ (0.06)	$ 0.32	$ 0.40	$ 0.50	$ 0.52	$ 0.36	$ 0.43	$ 1.68	$ 1.81	$ 1.38
net income per share-diluted	$ 1.00	$ (0.06)	$ 0.32	$ 0.40	$ 0.49	$ 0.51	$ 0.36	$ 0.43	$ 1.65	$ 1.78	$ 1.36

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

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