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Note 4 - Segment Reporting Concentration of Risk (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($) customer	Dec. 31, 2017 customer	Dec. 31, 2016 customer
Mortgage and Real Estate Services Segment
Corporate Cash and Investments Allocated to Subsidiary | $	$ 0.0
Customer Concentration Risk | Mortgage Insurance Segment | New Insurance Written
Concentration Risk, Percentage	10.00%	10.00%	10.00%
Entity Wide Revenue, Major Customer, Number of Customers	0	0	0
Customer Concentration Risk | Mortgage Insurance Segment | Earned Premium Benchmark, Amount
Concentration Risk, Percentage	10.00%	10.00%	10.00%
Entity Wide Revenue, Major Customer, Number of Customers	0	0	0
CALIFORNIA | Geographic Concentration Risk | Mortgage Insurance Segment | Primary Risk In Force
Concentration Risk, Percentage	12.30%	12.40%
CALIFORNIA | Geographic Concentration Risk | Mortgage Insurance Segment | New Insurance Written
Concentration Risk, Percentage	11.90%	14.10%	14.80%
Minimum | CALIFORNIA | Geographic Concentration Risk | Mortgage Insurance Segment | Primary Risk In Force
Concentration Risk, Percentage	10.00%

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- Definition

Corporate Cash and Investments Allocated to Subsidiary

+ References

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- Definition

Number of customers that account for 10 percent or more of an entity's revenues

+ References

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13531-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13537-108611

Reference 4: 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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