Note 2 - Significant Accounting Policies Accounting Policy (Details) (USD $)	12 Months Ended
	Dec. 31, 2013 group	Dec. 31, 2012	Dec. 31, 2011
Deferred Policy Acquisition Costs Disclosures [Abstract]
Deferred Policy Acquisition Cost, Amortization Expense	$ 41,664,000	$ 61,876,000	$ 52,763,000
Investments [Abstract]
Number of Investment Categories	3
Criteria For Establishing Reserve For Losses [Member]
Reserve for Losses and LAE [Abstract]
Number of Groups of States Used in Reserve Modeling	3
Minimum [Member]
Basis of Presentation [Abstract]
Equity Method Investment, Ownership Percentage	20.00%
Minimum [Member] | Criteria For Establishing Reserve For Losses [Member]
Reserve for Losses and LAE [Abstract]
Number Of Payments Missed For Insured Loans	2
Maximum [Member]
Basis of Presentation [Abstract]
Equity Method Investment, Ownership Percentage	50.00%
Investments [Abstract]
Maximum Maturity Duration for Short Term Investment Grouping	3 months
Maximum [Member] | Criteria For Establishing Reserve For Losses [Member]
Reserve for Losses and LAE [Abstract]
Period of Time That Insured Has to Rebut Decision to Rescind Coverage	90 days
Period of Time Insureds Have After Foreclosure to Provide Documents to Perfect a Claim	1 year
Majority [Member]
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative, Remaining Maturity	4 years
Computer Equipment [Member]
Company-Owned Life Insurance
Property, Plant and Equipment, Useful Life, Maximum	3 years
Furniture, Fixtures and Office Equipment [Member]
Company-Owned Life Insurance
Property, Plant and Equipment, Useful Life, Maximum	7 years
Financial Guaranty Segment
Deferred Policy Acquisition Costs Disclosures [Abstract]
Deferred Policy Acquisition Cost, Amortization Expense	13,179,000	27,745,000	16,712,000
Mortgage Insurance Segment
Reserve for Premium Deficiency [Abstract]
Number of Mortgage Insurance Product Categories	2
Deferred Policy Acquisition Costs Disclosures [Abstract]
Deferred Policy Acquisition Cost, Amortization Expense	28,485,000	34,131,000	36,051,000
Mortgage Insurance Segment | Maximum [Member]
Reserve for Losses and LAE [Abstract]
Number of Years That We Cap Calculating Interest on Defaulted Loan Principal	2 years
Number of Days That a Loan Is In Default When No Additional Reserve Is Created	240 days
Company Owned Life Insurance [Member]
Company-Owned Life Insurance
Cash Surrender Value of Life Insurance	$ 78,400,000	$ 76,500,000
Pool Insurance Mortgage Insurance Product [Member] | Insurance Claims [Member] | Maximum [Member]
Reserve for Losses and LAE [Abstract]
Under Our Master Insurance Policy Any Suit Or Action Arising From Any Right Of The Insured Under The Policy Must Be Commenced Within This Number Of Years After Such Right First Arose	3 years
Total Primary Insurance Mortgage Insurance Products [Member] | Insurance Claims [Member] | Maximum [Member]
Reserve for Losses and LAE [Abstract]
Under Our Master Insurance Policy Any Suit Or Action Arising From Any Right Of The Insured Under The Policy Must Be Commenced Within This Number Of Years After Such Right First Arose	2 years
Under Our Master Insurance Policy Any Suit Or Action Arising From Any Right Of Certain Other Policies Must Be Commenced Within This Number Of Years After Such Right First Arose	2 years