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Note H - Components of Net Periodic Benefit Cost (Details Textual) - USD ($) $ in Millions | 6 Months Ended
--- | ---
Jun. 30, 2020 | Jun. 30, 2019
Qualified Pension Plan [Member] |  |
Defined Benefit Plan, Minimum Employer Contributions, Fiscal Year | $ 6.0 |
Restoration Pension Plan [Member] |  |
Defined Benefit Plan, Plan Assets, Contributions by Employer | $ 0.9 | $ 0.4

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- Details
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