Note A - Summary of Significant Accounting Policies 1 (Details Textual) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounts Payable, Other, Current		$ 4,510,000	$ 1,308,000
Proceeds from Sale and Maturity of Debt Securities, Available-for-sale, Total		57,823,000	161,420,000	$ 173,060,000
Debt Securities, Available-for-sale, Realized Gain (Loss), Total		0	0	0
OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, before Tax, Total		24,000	145,000	135,000
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax, Total		0	0	0
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One		38,007,000
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five		5,006,000
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10		825,000
Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10		$ 25,143,000
Debt Securities, Available for Sale, Number of Days to Tender (Day)		7 days
Property, Plant and Equipment, Gross, Ending Balance		$ 96,488,000	93,982,000
Goodwill, Impairment Loss		0	0	0
Goodwill, Ending Balance		15,317,000	15,317,000
Impairment of Intangible Assets (Excluding Goodwill), Total		0	0
Finite-Lived Intangible Assets, Gross, Total		2,142,000
Finite-Lived Intangible Assets, Accumulated Amortization		304,000	83,000
Amortization of Intangible Assets, Total		221,000	83,000	2,167,000
Finite-Lived Intangible Asset, Expected Amortization, Year One		214,000
Finite-Lived Intangible Asset, Expected Amortization, Year Two		214,000
Finite-Lived Intangible Asset, Expected Amortization, Year Three		214,000
Finite-Lived Intangible Asset, Expected Amortization, Year Four		214,000
Finite-Lived Intangible Asset, Expected Amortization, Year Five		$ 214,000
Expected Prepayment Utilization Period (Year)		2 years
Contract with Customer, Liability, Decrease from Product Recall		$ 2,073,000
Advertising Expense		$ 2,655,000	245,000	181,000
Initial Product Return Period (Day)		60 days
Estimated Product Recall Payable		$ 2,769,000
Other Current Assets [Member]
Materials, Supplies, and Other		4,311,000	4,614,000
Accounts Payable and Accrued Liabilities [Member]
Contract with Customer, Liability, Current		4,723,000	1,847,000
Defense [Member]
Impairment of Long-Lived Assets Held-for-use	$ 2,975,000
Goodwill, Ending Balance		11,486,000
Goodwill, Impaired, Accumulated Impairment Loss		0
Impairment of Intangible Assets (Excluding Goodwill), Total	$ 46,000
Contract with Customer, Liability, Cumulative Catch-up Adjustment to Revenue, Modification of Contract			9,412,000
Contract with Customer, Liability, Revenue Recognized		0	9,574,000	$ 676,000
Revenue, Remaining Performance Obligation, Amount		320,214,000	310,385,000
Safety [Member]
Goodwill, Ending Balance		3,831,000
Goodwill, Impaired, Accumulated Impairment Loss		0
Housewares/Small Appliances [Member]
Materials, Supplies, and Other		11,217,000	9,396,000
Building [Member] | Defense [Member]
Construction in Progress, Gross		1,398,000	$ 2,413,000
Leased Manufacturing and Office Space [Member]
Property, Plant and Equipment, Gross, Ending Balance		$ 6,774,000
Minimum [Member]
Accounts Receivable, Collection Period (Day)		25 days
Finite-Lived Intangible Asset, Useful Life (Year)		2 years
Revenue Contract Period (Month)		3 months
Minimum [Member] | Housewares/Small Appliances [Member]
Standard Product Warranty, Coverage Period (Year)		1 year
Minimum [Member] | Building [Member]
Property, Plant and Equipment, Useful Life (Year)		15 years
Minimum [Member] | Machinery and Equipment [Member]
Property, Plant and Equipment, Useful Life (Year)		3 years
Minimum [Member] | Land Improvements [Member]
Property, Plant and Equipment, Useful Life (Year)		15 years
Maximum [Member]
Accounts Receivable, Collection Period (Day)		60 days
Finite-Lived Intangible Asset, Useful Life (Year)		15 years
Revenue Contract Period (Month)		24 months
Maximum [Member] | Housewares/Small Appliances [Member]
Standard Product Warranty, Coverage Period (Year)		12 years
Maximum [Member] | Building [Member]
Property, Plant and Equipment, Useful Life (Year)		40 years
Maximum [Member] | Machinery and Equipment [Member]
Property, Plant and Equipment, Useful Life (Year)		10 years
Maximum [Member] | Land Improvements [Member]
Property, Plant and Equipment, Useful Life (Year)		20 years