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Note 9 - Employee Benefit Plans - Investment Policy Allocation (Details) | Dec. 31, 2020
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Large Cap US Equity [Member] |
Investment policy allocation | 17.00%
Large Cap US Equity [Member] | Maximum [Member] |
Investment policy allocation | 20.00%
Small Cap US Equity [Member] |
Investment policy allocation | 8.00%
Small Cap US Equity [Member] | Maximum [Member] |
Investment policy allocation | 10.00%
Debt Security, Government, Non-US [Member] |
Investment policy allocation | 25.00%
Debt Security, Government, Non-US [Member] | Maximum [Member] |
Investment policy allocation | 30.00%
Fixed Income Funds [Member] |
Investment policy allocation | 23.00%
Fixed Income Funds [Member] | Maximum [Member] |
Investment policy allocation | 28.00%
Real Estate [Member] |
Investment policy allocation | 15.00%
Real Estate [Member] | Maximum [Member] |
Investment policy allocation | 18.00%
Absolute Return [Member] |
Investment policy allocation | 5.00%
Absolute Return [Member] | Maximum [Member] |
Investment policy allocation | 7.00%
Real Return [Member] |
Investment policy allocation | 7.00%
Real Return [Member] | Maximum [Member] |
Investment policy allocation | 13.00%

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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: 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 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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