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Note 5 - Retirement Plans - Weighted Average Actuarial Assumptions (Details) | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Discount rate | 2.80% | 2.42% |
Compensation increase | 4.30% | 4.40% |
Discount rate for benefit obligations | 2.42% | 3.26% | 4.23%
Discount rate for interest on benefit obligations | 1.90% | 2.89% | 3.94%
Discount rate for service cost | 2.61% | 3.42% | 4.33%
Discount rate for interest on service cost | 2.53% | 3.36% | 4.30%
Expected return on plan assets | 6.25% | 7.00% | 7.00%
Compensation increase | 4.40% | 4.10% | 4.10%

X
- Definition Represents discount rate for benefit obligations of net periodic benefit cost for assumption used calculating Defined benefit plan. + References No definition available. + Details
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- Definition Represents discount rate for interest on benefit obligations for defined benefit plan assumptions used calculating for defined benefit plan. + References No definition available. + Details
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- Definition Represents discount rate for interest on service cost for defined benefit plan assumption used calculating net periodic benefit cost. + References No definition available. + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows for service cost , used to determine net periodic benefit cost of defined benefit plan. + References No definition available. + Details
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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 http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related 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)(2) -URI http://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 http://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 http://asc.fasb.org/extlink&oid=123447040&loc=d3e2919-114920 + Details
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