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Note H - Employee Benefit Plans (Details Textual) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Defined Benefit Plan, Expected Future Benefit Payment, Year One | $ 10,796 |
Defined Benefit Plan, Period Of Operating, History and Sufficient Trading Volume of Invested Entity (Year) | 5 years |
Minimum [Member] |  |
Defined Benefit Plan, Period to Meet Goals (Year) | 3 years |
Maximum [Member] |  |
Defined Benefit Plan, Period to Meet Goals (Year) | 5 years |
Pension Plan [Member] |  |
Defined Benefit Plan, Plan Assets, Benefits Paid | $ 10,495 | $ 10,382
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation | 198,586 | 189,807
Defined Benefit Plan, Expected Amortization of Gain (Loss), Next Fiscal Year | 3,500 |
Qualified Plan I [Member] | Pension Plan [Member] |  |
Defined Benefit Plan, Expected Future Benefit Payment, Year One | $ 1,800 |
Defined Benefit Plan, Amortization Period (Year) | 17 years 109 days |
Qualified Plan II [Member] | Pension Plan [Member] |  |
Defined Benefit Plan, Expected Future Benefit Payment, Year One | $ 2,200 |
Defined Benefit Plan, Amortization Period (Year) | 27 years |
Restoration Pension Plan [Member] | Pension Plan [Member] |  |
Defined Benefit Plan, Plan Assets, Benefits Paid | $ 1,700 |
Restoration Plan [Member] | Pension Plan [Member] |  |
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation | $ 28,700 | $ 27,600

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- Definition Represents history and sufficient trading volume of interest entity for period of operating of defined benefit plan. + References No definition available. + Details
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- Definition Represents the defined benefit plan period required to meet investment policy's goal. + References No definition available. + Details
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- Definition Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (s) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year. + 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 (f) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2417-114920 Reference 2: 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 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2417-114920 + Details
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- Definition Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. + 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 (b)(5) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964 + Details
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