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Note 8 - Benefit Plans - Pension Plans With Projected Benefit Obligation in Excess of Plan Assets (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Projected benefit obligation | $ 33,115 | $ 28,470
Fair value of plan assets | (18,754) | (19,939)
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Funded Status | 14,361 | 8,531
Pension Plan [Member] |  |
Projected benefit obligation | 18,778 | 18,114
Fair value of plan assets | (18,754) | (19,939)
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Funded Status | 24 | (1,825)
Supplemental Employee Retirement Plan [Member] |  |
Projected benefit obligation | 14,337 | 10,356
Fair value of plan assets | 0 | 0
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Funded Status | $ 14,337 | $ 10,356

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- Definition The funded status of a pension plan with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented. + References No definition available. + Details
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- Definition Amount of plan asset for defined benefit pension plan with projected 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 + Details
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- Definition Amount of projected benefit obligation for defined benefit pension plan with projected 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 + Details
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