Note 10 - Losses and LAE Rescissions And Denials (Details) (USD $) In Millions, unless otherwise specified	36 Months Ended																					12 Months Ended
	Dec. 31, 2011	Dec. 31, 2011 Q1 2009 [Member]		Dec. 31, 2011 Q2 2009 [Member]		Dec. 31, 2011 Q3 2009 [Member]		Dec. 31, 2011 Q4 2009 [Member]		Dec. 31, 2011 Q1 2010 [Member]		Dec. 31, 2011 Q2 2010 [Member]		Dec. 31, 2011 Q3 2010 [Member]		Dec. 31, 2011 Q4 2010 [Member]		Dec. 31, 2011 Q1 2011 [Member]		Dec. 31, 2011 Q2 2011 [Member]		Dec. 31, 2011 First Lien Claims First Loss Position [Member]		Dec. 31, 2010 First Lien Claims First Loss Position [Member]		Dec. 31, 2009 First Lien Claims First Loss Position [Member]		Dec. 31, 2011 First Lien Claims Second Loss Position [Member]		Dec. 31, 2010 First Lien Claims Second Loss Position [Member]		Dec. 31, 2009 First Lien Claims Second Loss Position [Member]		Dec. 31, 2011 Mortgage Insurance Segment		Dec. 31, 2010 Mortgage Insurance Segment		Dec. 31, 2009 Mortgage Insurance Segment		Dec. 31, 2011 Mortgage Insurance Segment	Dec. 31, 2010 Mortgage Insurance Segment
Rescissions And Denials [Line Items]
Decrease To Our Loss Reserves Due To Estimated Rescissions And Denials																																								$ 631	$ 922
Impact To Loss Reserves Based On One Percentage Change In Primary Claim Severity																																								96
Claims Rescissions and Denials [Abstract]
Claim rescissions																						360.0		339.2		330.7		114.2		199.1		372.9
Claim denials																						133.9		200.2		67.4		37.0		61.5		54.6
Total rescissions and denials																						493.9	[1]	539.4	[1]	398.1	[1]	151.2	[2]	260.6	[2]	427.5	[2]
Total First Lien Claims Rescinded Or Denied																																		645.1	[3]	800.0	[3]	825.6	[3]
Non Overturned Rebuttals on Rescinded First Lien Claims [Abstract]
Total Non Overturned Rebuttals On Rescinded First Lien Claims First Loss Position	460.7
Total Non Overturned Rebuttals On Rescinded First Lien Claims Second Loss Position	191.8
Total Non Overturned Rebuttals On Rescinded First Lien Claims	652.5
Accrued Liability For Premiums Expected To Be Refunded From Rescissions																																		$ 57.2		$ 43.5
Cumulative Denial And Rescission Rates Net Of Reinstatements [Abstract]
Claim Received Quarter		Q1 2009		Q2 2009		Q3 2009		Q4 2009		Q1 2010		Q2 2010		Q3 2010		Q4 2010		Q1 2011		Q2 2011
Cummulative Rescission Rate For Each Quarter		23.80%	[4]	25.60%	[4]	22.70%	[4]	20.80%	[4]	18.90%	[4]	18.30%	[4]	16.60%	[4]	18.20%	[4]	21.40%	[4]	22.60%	[4]
Percentage Of Claims Resolved		100.00%	[5]	100.00%	[5]	100.00%	[5]	100.00%	[5]	99.00%	[5]	99.00%	[5]	98.00%	[5]	97.00%	[5]	92.00%	[5]	79.00%	[5]

[1] Related to claims from policies in which we were in a first loss position and would have paid the claim absent the rescission or denial.

[2] Related to claims from policies in which we were in a second loss position. These rescissions or denials may not have resulted in a claim payment obligation due to deductibles and other exposure limitations included in our policies.

[3] Includes a small number of submitted claims that were subsequently withdrawn by the insured.

[4] Rescission/Denial rates represent the ratio of claims rescinded or denied to claims received (by claim count) and represent (as of December 31, 2011) the cumulative rate for each quarter based on number of claims received during that quarter. Until all of the claims received during the periods shown have been internally resolved, the rescission/denial rates for each quarter will be subject to change. These rates also will remain subject to change based on reinstatements of previously rescinded policies or denied claims.

[5] The percentage of claims resolved for each quarter presented in the table above, represents the number of claims that have been internally resolved as a percentage of the total number of claims received for that specific quarter. A claim is considered internally resolved when it is either paid or it is concluded that the claim should be denied or rescinded, though such denials or rescissions could be challenged and, potentially reinstated. For the third and fourth quarters of 2011, a significant portion of claims received for those quarters have not been internally resolved; therefore, we do not believe the cumulative rescission rates for those periods are presently meaningful and are therefore not presented.