Note 8 - Losses and LAE Mortgage Insurance Loss Reserves Rollforward (Details) (USD $)			3 Months Ended				9 Months Ended				12 Months Ended					3 Months Ended	9 Months Ended
	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2012 Mortgage Insurance Segment		Sep. 30, 2011 Mortgage Insurance Segment		Sep. 30, 2012 Mortgage Insurance Segment		Sep. 30, 2011 Mortgage Insurance Segment		Dec. 31, 2011 Mortgage Insurance Segment		Sep. 30, 2012 Default To Claim Rate Assumptions Twelve Or More Missed Payments [Member] payment	Sep. 30, 2012 Default To Claim Rate Assumptions Two Missed Payments [Member] payment	Sep. 30, 2012 Default To Claim Rate Assumptions Three Missed Payments [Member] payment	Jun. 30, 2012 Smart Home [Member] transaction	Sep. 30, 2012 Smart Home [Member]
Loss reserve [Roll Forward]
Balance at beginning of period			$ 3,155,343,000		$ 3,268,582,000		$ 3,247,900,000		$ 3,524,971,000		$ 3,524,971,000
Less reinsurance recoverables	94,584,000	157,985,000	97,845,000	[1]	160,664,000	[1]	151,569,000	[1]	223,254,000	[1]	223,254,000	[1]
Balance at beginning of period, net of reinsurance recoverables			3,057,498,000		3,107,918,000		3,096,331,000		3,301,717,000		3,301,717,000
Add losses and LAE incurred in respect of default notices reported and unreported in [Abstract]
Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims Current Year			248,806,000	[2]	338,360,000	[2]	686,080,000	[2]	775,479,000	[2]
Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims, Prior Years			(77,001,000)		(61,761,000)		(71,468,000)		185,085,000
Total incurred			171,805,000		276,599,000		614,612,000		960,564,000
Deduct paid claims and LAE related to [Abstract]
Current year			2,912,000	[2]	59,693,000	[2]	3,185,000	[2]	61,894,000	[2]
Prior years			269,486,000		270,203,000		750,853,000		1,145,766,000
Paid losses and LAE			272,398,000		329,896,000		754,038,000		1,207,660,000
Balance at end of period, net of reinsurance recoverables			2,956,905,000		3,054,621,000		2,956,905,000		3,054,621,000		3,096,331,000
Add reinsurance recoverables	94,584,000	157,985,000	89,801,000	[1]	160,233,000	[1]	89,801,000	[1]	160,233,000	[1]	151,569,000	[1]
Balance at end of period			3,046,706,000		3,214,854,000		3,046,706,000		3,214,854,000		3,247,900,000
Increase (Decrease) in Reinsurance Recoverable																	43,600,000
Number of Transactions Terminated																1
Default To Claim Rate Detail [Abstract]
Weighted Average Default To Claim Rate Assumption Net Of Denials And Rescissions							46.00%				43.00%
Weighted Average Default To Claim Rate Assumption Excluding Pending Claims Net Of Denials And Rescissions							39.00%
Default To Claim Rate Estimate Net Of Rescission And Denial Estimates For Insured Loans That Missed Two To Three Monthly Payments							20.00%
Default To Claim Estimate Net Of Rescission And Denial Estimates For Loans That Missed Twelve Or More Monthly Payments							45.00%
Number Of Payments Missed For Insured Loans													12	2	3
Impact To Our Loss Reserves Due To Estimated Rescissions And Denials [Abstract]
Decrease To Our Loss Reserves Due To Estimated Rescissions And Denials			477,000,000				477,000,000				631,000,000
Increase To Our Loss Reserves Due To Estimated Future Reinstatements Of Previously Rescinded Policies And Denied Claims			239,000,000				239,000,000				129,000,000
IBNR Reserve Estimate [Abstract]
Liability for Unpaid Claims and Claims Adjustment Expense, Incurred but Not Reported (IBNR) Claims, Amount			261,600,000				261,600,000				170,600,000
Claim Severity Detail [Abstract]
First Lien Primary Claim Severity							27.00%
Percentage Point Change In Severity For Assumption Shift Analysis			1.00%				1.00%
Impact To Loss Reserves Based On One Percentage Change In Primary Claim Severity			88,000,000				88,000,000
First Lien Pool Claim Severity							45.00%
Impact To Loss Reserves Based On One Percentage Change In Pool Claim Severity			4,000,000				4,000,000
Impact To Loss Reserves Based On One Percentage Increase In Default To Claim Rate			$ 56,000,000				$ 56,000,000

[1] Related to ceded losses on captive reinsurance transactions, Smart Home and quota share reinsurance transactions.

[2] Related to underlying defaulted loans with a most recent date of default notice in the year indicated. For example, if a loan had defaulted in a prior year, but then subsequently cured and later re-defaulted in the current year, that default would be considered a current year default.