Note M - Leases - Operating Lease (Details) $ in Thousands	Mar. 31, 2021 USD ($)
2021 (remaining)	$ 472
2022	544
2023	340
2024	114
Total undiscounted operating lease payments	1,470
Less: Imputed interest	$ (66)
Weighted-average remaining lease term for operating leases (years) (Year)	2 years 7 months 2 days
Weighted-average discount rate for operating leases	3.60%
Accrued Expenses And Other Liabilities And Other Long-term Liabilities [Member]
Present value of operating lease liabilities	$ 1,404
Right-of-use assets (recorded in other non-current assets)	1,404
Total operating lease liabilities	1,404
Other Current Liabilities [Member]
Current lease liabilities (recorded in other current liabilities)	631
Other Noncurrent Liabilities [Member]
Long-term lease liabilities (recorded in other long-term liabilities)	$ 773

Amount of lessee's undiscounted obligation for lease payment for operating lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease having initial or remaining lease term in excess of one year to be paid in remainder of current fiscal year.

+ References

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Amount of lessee's right to use underlying asset under operating lease.

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- Definition

Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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