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Note H - Employee Benefit Plans - Acceptable Level of Volatility (Details) | Dec. 31, 2020
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Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities [Member] |
Target rate | 64.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities [Member] | Minimum [Member] |
Target rate | 54.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities [Member] | Maximum [Member] |
Target rate | 74.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities, US, Large Cap [Member] |
Target rate | 23.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities, US, Large Cap [Member] | Minimum [Member] |
Target rate | 18.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities, US, Large Cap [Member] | Maximum [Member] |
Target rate | 28.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities, US, Mid Cap [Member] |
Target rate | 15.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities, US, Mid Cap [Member] | Minimum [Member] |
Target rate | 10.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities, US, Mid Cap [Member] | Maximum [Member] |
Target rate | 20.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities, US, Small Cap [Member] |
Target rate | 8.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities, US, Small Cap [Member] | Minimum [Member] |
Target rate | 4.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities, US, Small Cap [Member] | Maximum [Member] |
Target rate | 12.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities, Non-US [Member] |
Target rate | 13.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities, Non-US [Member] | Minimum [Member] |
Target rate | 8.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities, Non-US [Member] | Maximum [Member] |
Target rate | 25.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities, Emerging Markets [Member] |
Target rate | 5.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities, Emerging Markets [Member] | Minimum [Member] |
Target rate | 0.00%
Other Pension Plan [Member] | Defined Benefit Plan, Equity Securities, Emerging Markets [Member] | Maximum [Member] |
Target rate | 8.00%
Pension Plan [Member] | Emerging Markets [Member] |
Target rate | 34.00%
Pension Plan [Member] | Emerging Markets [Member] | Minimum [Member] |
Target rate | 24.00%
Pension Plan [Member] | Emerging Markets [Member] | Maximum [Member] |
Target rate | 44.00%
Pension Plan [Member] | Investment Grade [Member] |
Target rate | 34.00%
Pension Plan [Member] | Investment Grade [Member] | Minimum [Member] |
Target rate | 24.00%
Pension Plan [Member] | Investment Grade [Member] | Maximum [Member] |
Target rate | 44.00%
Pension Plan [Member] | Cash Equivalent [Member] |
Target rate | 2.00%
Pension Plan [Member] | Cash Equivalent [Member] | Minimum [Member] |
Target rate | 0.00%
Pension Plan [Member] | Cash Equivalent [Member] | Maximum [Member] |
Target rate | 40.00%

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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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