Segment Information - Balance Sheet Information by Operating Segments (Detail) - USD ($)		9 Months Ended
		Jan. 31, 2021	Feb. 02, 2020	May 03, 2020
Segment Reporting Information [Line Items]
Inventory		$ 57,794,000	$ 54,009,000	$ 47,907,000	[1]
Cash and cash equivalents		35,987,000	21,640,000	69,790,000	[1]
Short-term investments - available for sale		5,548,000	7,580,000	923,000	[1]
Short-term investments - held-to-maturity		9,785,000	3,171,000	4,271,000	[1]
Current income taxes receivable			776,000	1,585,000	[1]
Current assets - discontinued operation			4,738,000
Other current assets		3,116,000	3,112,000	2,116,000	[1]
Deferred income taxes		640,000	920,000	793,000	[1]
Property, plant and equipment		42,385,000	44,652,000	43,147,000	[1]
Right of use assets		6,206,000	4,574,000	3,903,000	[1]
Goodwill		0	13,569,000	0
Intangible assets		3,098,000	3,617,000	3,380,000	[1]
Long-term investments - rabbi trust		8,232,000	7,804,000	7,834,000	[1]
Long-term investments - held-to-maturity		512,000	2,224,000	2,076,000	[1]
Noncurrent income taxes receivable			733,000
Other assets		555,000	464,000	664,000	[1]
Noncurrent assets - discontinued operation			9,241,000
Investment in unconsolidated joint venture		1,723,000	1,668,000	1,602,000	[1]
Total assets		211,978,000	212,140,000	215,084,000	[1]
Capital expenditures	[2]	4,453,000	4,171,000
Depreciation expense		5,203,000	5,880,000
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total assets		142,013,000	128,137,000	118,912,000
Depreciation expense		5,203,000	5,880,000
Operating Segments [Member] | Mattress Fabrics [Member]
Segment Reporting Information [Line Items]
Accounts receivable		17,722,000	12,940,000	12,212,000
Inventory		30,326,000	29,753,000	26,620,000
Property, plant and equipment	[3]	39,550,000	42,368,000	40,682,000
Right of use assets	[4]	1,077,000	426,000	362,000
Investment in unconsolidated joint venture		1,723,000	1,668,000	1,602,000
Total assets		90,398,000	87,155,000	81,478,000
Capital expenditures	[2]	3,886,000	3,416,000
Depreciation expense		4,579,000	5,017,000
Operating Segments [Member] | Upholstery Fabrics [Member]
Segment Reporting Information [Line Items]
Accounts receivable		18,675,000	12,908,000	12,881,000
Inventory		27,468,000	24,256,000	21,287,000
Property, plant and equipment	[5]	1,953,000	1,675,000	1,633,000
Right of use assets	[6]	3,519,000	2,143,000	1,633,000
Total assets		51,615,000	40,982,000	37,434,000
Capital expenditures	[2]	259,000	253,000
Depreciation expense		624,000	577,000
Operating Segments [Member] | Discontinued Operation [Member]
Segment Reporting Information [Line Items]
Capital expenditures	[2]		104,000
Depreciation expense			286,000
Unallocated Corporate [Member]
Segment Reporting Information [Line Items]
Cash and cash equivalents		35,987,000	21,640,000	69,790,000
Short-term investments - available for sale		5,548,000	7,580,000	923,000
Short-term investments - held-to-maturity		9,785,000	3,171,000	4,271,000
Current income taxes receivable			776,000	1,585,000
Current assets - discontinued operation			4,738,000
Other current assets		3,116,000	3,112,000	2,116,000
Deferred income taxes		640,000	920,000	793,000
Property, plant and equipment	[7]	882,000	609,000	832,000
Right of use assets	[8]	1,610,000	2,005,000	1,908,000
Goodwill			13,569,000
Intangible assets		3,098,000	3,617,000	3,380,000
Long-term investments - rabbi trust		8,232,000	7,804,000	7,834,000
Long-term investments - held-to-maturity		512,000	2,224,000	2,076,000
Noncurrent income taxes receivable			733,000
Other assets		555,000	464,000	664,000
Long-term note receivable affiliated with discontinued operation			1,800,000
Noncurrent assets - discontinued operation			9,241,000
Total assets		211,978,000	212,140,000	$ 215,084,000
Capital expenditures	[2]	$ 308,000	$ 398,000

[1] Derived from audited financial statements.

[2] Capital expenditure amounts are stated on the accrual basis. See Consolidated Statements of Cash Flows for capital expenditure amounts on a cash basis.

[3] The $39.6 million as of January 31, 2021, represents property, plant, and equipment of $27.3 million and $12.3 million located in the U.S. and Canada, respectively. The $42.4 million as of February 2, 2020, represents property, plant, and equipment of $28.7 million and $13.7 million located in the U.S. and Canada, respectively.   The $40.7 million as of May 3, 2020, represents property, plant, and equipment of $27.7 million and $13.0 million located in the U.S. and Canada, respectively.

[4] The $1.1 million as of January 31, 2021, represents right of use assets of $632,000 and $445,000 located in the U.S. and Canada, respectively.  The $426,000 as of February 2, 2020, and the $362,000 as of May 3, 2020, represents right of use assets located in the U.S.

[5] The $2.0 million as of January 31, 2021, represents property, plant, and equipment of $1.1 million and $881,000 located in the U.S. and China, respectively. The $1.7 million as of February 2, 2020, represents property, plant, and equipment of $1.2 million and $469,000 located in the U.S. and China, respectively.   The $1.6 million as of May 3, 2020, represents property, plant, and equipment of $1.2 million and $471,000 located in the U.S. and China, respectively.

[6] The $3.5 million as of January 31, 2021, represents right of use assets of $2.4 million and $1.1 million located in China and the U.S., respectively.  The $2.1 million as of February 2, 2020, represents right of use assets of $1.1 million and $1.0 million located in China and the U.S., respectively.  The $1.6 million as of May 3, 2020, represents right of use assets of $857,000 and $776,000 located in the U.S. and China, respectively.

[7] The $882,000, $609,000 and $832,000 as of January 31, 2021, February 2, 2020, and May 3, 2020, respectively, represent property, plant, and equipment associated with unallocated corporate departments and corporate departments shared by our mattress fabrics and upholstery fabrics segments. Property, plant, and equipment associated with our corporate departments reside in the U.S.

[8] The $1.6 million, $2.0 million, and $1.9 million as of January 31, 2021, February 2, 2020, and May 3, 2020, respectively, represent right of use assets located in the U.S.