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Note 4 - Segment Reporting - Concentration of Risk (Details) - Customer Concentration Risk - customer | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
New Insurance Written |  |  |
Entity Wide Revenue, Major Customer, Number of Customers | 1 | 0 | 0
Concentration Risk, Percentage | 10.00% | 10.00% | 10.00%
Consolidated Revenue |  |  |
Entity Wide Revenue, Major Customer, Number of Customers | 0 | 0 | 0
Concentration Risk, Percentage | 10.00% | 10.00% | 10.00%

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