Note 11 - Losses and LAE Reserve Activity (Details) $ in Millions		12 Months Ended
		Dec. 31, 2019 USD ($) incident	Dec. 31, 2018	Dec. 31, 2017
Hurricanes Harvey and Irma
Number of Natural Disasters | incident		2
Mortgage Insurance Segment | Total primary reserves | Incurred But Not Reported
Liability for Future Policy Benefits, Other Increase (Decrease) | $		$ 30.5
Mortgage Insurance Segment | Primary Mortgage Product
Default To Claim Rate Estimate, Gross, For New Defaults	[1]	7.50%	8.00%	10.00%
Default To Claim Estimate, Gross, For Foreclosure Stage Defaults		70.00%	75.00%	81.00%
Mortgage Insurance Segment | Primary Mortgage Product | Hurricanes Harvey and Irma
Default To Claim Rate Estimate, Gross, For New Defaults		3.00%
Mortgage Insurance Segment | Primary Mortgage Product | Aged less than or equal to 5 years
Default To Claim Rate Estimate, Gross, For Pre-Foreclosure Stage Defaults	[1],[2]	23.90%	25.80%	28.30%
Mortgage Insurance Segment | Primary Mortgage Product | Aged greater than 5 Years
Default To Claim Rate Estimate, Gross, For Pre-Foreclosure Stage Defaults		63.00%	68.00%	62.00%
Mortgage Insurance Segment | Primary Mortgage Product | Aged less than or equal to 5 Years - more aged
Default To Claim Rate Estimate, Gross, For Pre-Foreclosure Stage Defaults	[2]	55.60%	57.40%	62.00%

[1] A 3% Default to Claim Rate assumption was assigned to the new primary defaults from FEMA Designated Areas associated with Hurricanes Harvey and Irma that were reported subsequent to those two natural disasters in 2017 and through February 2018.

[2] Represents the weighted average Default to Claim Rate for all defaults not in foreclosure stage that have been in default for up to five years, including new defaults. The estimated Default to Claim Rates applied to defaults within this population vary by Time in Default, and range from the Default to Claim Rates on new defaults shown above, up to 55.6%, 57.4% and 62.0% for more aged defaults in this category as of December 31, 2019, 2018, and 2017, respectively.