Segment Information - Statement of Operations for Operating Segments (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 30, 2022	Jan. 31, 2021	Jan. 30, 2022	Jan. 31, 2021
Segment Reporting Information [Line Items]
net sales	$ 80,291	$ 79,341	$ 237,899	$ 220,656
gross profit	9,110	13,872	32,336	38,035
selling, general, and administrative expenses	8,007	9,835	26,275	27,597
income from operations	1,103	4,037	6,061	10,438
Interest expense				(51)
interest income	214	90	347	208
other expense	(322)	(1,010)	(963)	(2,057)
income before income taxes	995	3,117	5,445	8,538
Mattress Fabrics [Member]
Segment Reporting Information [Line Items]
net sales	38,439	38,600	122,380	114,733
Upholstery Fabrics [Member]
Segment Reporting Information [Line Items]
net sales	41,852	40,741	115,519	105,923
Operating Segments [Member]
Segment Reporting Information [Line Items]
net sales	80,291	79,341	237,899	220,656
selling, general, and administrative expenses	8,007	9,835	26,275	27,597
Operating Segments [Member] | Mattress Fabrics [Member]
Segment Reporting Information [Line Items]
net sales	38,439	38,600	122,380	114,733
gross profit	3,164	6,458	16,106	18,650
selling, general, and administrative expenses	2,800	3,161	8,991	9,125
income from operations	364	3,297	7,115	9,525
Operating Segments [Member] | Upholstery Fabrics [Member]
Segment Reporting Information [Line Items]
net sales	41,852	40,741	115,519	105,923
gross profit	5,946	7,414	16,230	19,385
selling, general, and administrative expenses	3,500	3,551	10,491	10,122
income from operations	2,446	3,863	5,739	9,263
Unallocated Corporate [Member]
Segment Reporting Information [Line Items]
selling, general, and administrative expenses	1,707	3,123	6,793	8,350
income from operations	$ (1,707)	$ (3,123)	$ (6,793)	$ (8,350)