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Note H - Employee Benefit Plans - Weighted-average Assumptions Used for Measurement of Defined Pension Plans (Details) | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021
Qualified Plan I [Member] |  |
Weighted-average assumptions used to determine net periodic benefit cost | 2.75% | 2.37%
Expected return on plan assets | 4.25% | 5.50%
Weighted-average assumptions used to determine benefit obligations, discount rate | 5.13% | 2.75%
Qualified Plan II [Member] |  |
Weighted-average assumptions used to determine net periodic benefit cost | 2.92% |
Expected return on plan assets | 5.75% |
Weighted-average assumptions used to determine benefit obligations, discount rate | 5.18% | 2.92%
Restoration Plan [Member] |  |
Weighted-average assumptions used to determine net periodic benefit cost | 2.73% | 2.34%
Weighted-average assumptions used to determine benefit obligations, discount rate | 5.12% | 2.73%

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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 8 -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e2919-114920 + Details
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