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Note 4 - Segment Reporting Concentration of Risk (Details) - Customer Concentration Risk - Mortgage Insurance Segment - customer | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
New Insurance Written |  |  |
Entity Wide Revenue, Major Customer, Number of Customers | 0 | 0 | 0
Concentration Risk, Percentage | 10.00% | 10.00% | 10.00%
Earned Premium Benchmark, Amount |  |  |
Entity Wide Revenue, Major Customer, Number of Customers | 0 | 0 | 0
Concentration Risk, Percentage | 10.00% | 10.00% | 10.00%

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- Definition Number of customers that account for 10 percent or more of an entity's revenues + References No definition available. + Details
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