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Note 4 - Periodic Pension Expense (Details Textual) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 USD ($) | Mar. 31, 2021 | Jun. 30, 2020 USD ($) | Jun. 30, 2021 USD ($) | Jun. 30, 2020 USD ($)
Defined Benefit Plans Number of Plans |  | 2 |  |  |
Defined Benefit Plans Retirement Age |  | 65 |  |  |
Defined Benefit Plan, Termination Charge | $ 6,945 |  | $ 0 | $ 6,945 | $ 0
Noncontributory Qualified Defined Pension Plans [Member] |  |  |  |  |
Defined Benefit Plan, Benefit Obligation, Payment for Settlement | 13,800 |  |  |  |
Defined Benefit Plan, Termination Charge | 6,900 |  |  | 6,900 |
Defined Benefit Plan, Remaining Undistributed Asset Surplus | 1,300 |  |  | 1,300 |
Noncontributory Qualified Defined Pension Plans [Member] | Annuitization Benefit [Member] |  |  |  |  |
Guaranteed Benefit Liability, Net, Ending Balance | $ 3,000 |  |  | $ 3,000 |

X
- Definition Represents the amount of remaining undistributed asset surplus under a defined benefit plan. + References No definition available. + Details
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X
- Definition Represents the amount recognized in earnings during the period for the termination of a defined benefit plan. + References No definition available. + Details
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- Definition Defined benefit plans number of plans + References No definition available. + Details
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- Definition Amount of payment, which decreases benefit obligation of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract. Excludes decreases to benefit obligation for remeasurement due to settlement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(10) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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X
- Definition Sum of the amount of expected guaranteed benefits in excess of the projected account balances for minimum guaranteed benefit contracts, as of the balance sheet date, net of reinsurance recoverables, for all guaranteed benefit types. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 20 -Section 55 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=124504833&loc=d3e7104-158389 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 80 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124508989&loc=d3e19393-158473 + Details
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- Details
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