Note 11 - Losses and LAE - Concentration of Risk (Details) - state	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Number of States That Accounted for More Than 10% of Mortgage Insurance Business Measured by Primary Risk in Force	0
CALIFORNIA \| Mortgage segment \| Primary Risk In Force \| Geographic Concentration Risk
Concentration Risk, Percentage		11.20%
CALIFORNIA \| Mortgage segment \| New Insurance Written \| Geographic Concentration Risk
Concentration Risk, Percentage	10.40%	10.60%	11.90%
CALIFORNIA \| Mortgage segment \| Minimum \| Primary Risk In Force \| Geographic Concentration Risk
Concentration Risk, Percentage	10.00%	10.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13531-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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