Note 11 - Losses and LAE Reserve Activity (Details) - incident	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2016
Mortgage Insurance Segment | Primary Mortgage Product
Default To Claim Rate Estimate, Gross, For New Defaults	8.00%	10.00%		12.00%
Hurricanes Harvey and Irma
Number of Natural Disasters			2
Hurricanes Harvey and Irma | Mortgage Insurance Segment | Primary Mortgage Product
Default To Claim Rate Estimate, Gross, For New Defaults			3.00%