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Note M - Subsequent Events (Details Textual) - USD ($) $ in Millions | Jan. 14, 2022 | Mar. 12, 2021 | Sep. 19, 2020 | Jan. 31, 2022 | Dec. 31, 2021
--- | --- | --- | --- | --- | ---
Stock Repurchase Program, Additional Authorized Amount |  | $ 3 | $ 2 |  |
Stock Repurchase Program, Authorized Amount |  | $ 15 | $ 12 |  |
Wells Fargo Bank, N.A. [Member] |  |  |  |  |
Maximum Dividends Issued Upon Repurchasing Stock |  |  |  |  | $ 5
Subsequent Event [Member] |  |  |  |  |
Stock Repurchase Program, Additional Authorized Amount | $ 3 |  |  |  |
Stock Repurchase Program, Authorized Amount | $ 18 |  |  |  |
Subsequent Event [Member] | Wells Fargo Bank, N.A. [Member] |  |  |  |  |
Maximum Dividends Issued Upon Repurchasing Stock |  |  |  | $ 7 |

X
- Definition Annual limit to repurchase stock or issue dividends under covenant of debt instrument. + References No definition available. + Details
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X
- Definition Additional amount of stock repurchase plan authorized. + References No definition available. + Details
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X
- Definition Amount of stock repurchase plan authorized. + References No definition available. + Details
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X
- Details
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X
- Details
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