Note 8 - Losses and LAE Mortgage Insurance Loss Reserves Rollforward (Details) (USD $)	3 Months Ended				6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011		Jun. 30, 2012		Jun. 30, 2011		Dec. 31, 2011
Loss reserve [Roll Forward]
Less reinsurance recoverables									$ 157,985,000
Deduct paid claims and LAE related to [Abstract]
Add reinsurance recoverables	103,143,000				103,143,000				157,985,000
Mortgage Insurance Segment
Loss reserve [Roll Forward]
Balance at beginning of period	3,230,938,000		3,542,797,000		3,247,900,000		3,524,971,000
Less reinsurance recoverables	118,071,000	[1]	192,258,000	[1]	(151,569,000)	[1]	223,254,000
Balance at beginning of period, net of reinsurance recoverables	3,112,867,000		3,350,539,000		3,096,331,000		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	218,929,000	[2]	246,433,000	[2]	437,274,000	[2]	437,119,000	[2]
Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims, Prior Years	(10,851,000)		23,559,000		5,533,000		246,846,000
Total incurred	208,078,000		269,992,000		442,807,000		683,965,000
Deduct paid claims and LAE related to [Abstract]
Current year	273,000	[2]	1,364,000	[2]	273,000	[2]	2,201,000	[2]
Prior years	263,174,000		511,249,000		481,367,000		875,563,000
Paid losses and LAE	263,447,000		512,613,000		481,640,000		877,764,000
Balance at end of period, net of reinsurance recoverables	3,057,498,000		3,107,918,000		3,057,498,000		3,107,918,000
Add reinsurance recoverables	97,845,000	[1]	160,664,000	[1]	97,845,000	[1]	160,664,000	[1]
Balance at end of period	3,155,343,000		3,268,582,000		3,155,343,000		3,268,582,000
Default To Claim Rate Detail [Abstract]
Weighted Average Default To Claim Rate Assumption Net Of Denials And Rescissions	46.00%				46.00%				43.00%
Default To Claim Rate Estimate Net Of Rescission And Denial Estimates For Insured Loans That Missed Two To Three Monthly Payments	20.00%				20.00%
Default To Claim Estimate Net Of Rescission And Denial Estimates For Loans That Missed Twelve Or More Monthly Payments	45.00%				45.00%
Impact To Our Loss Reserves Due To Estimated Rescissions And Denials [Abstract]
Decrease To Our Loss Reserves Due To Estimated Rescissions And Denials	532,000,000				532,000,000				631,000,000
Increase To Our Loss Reserves Due To Estimated Future Reinstatements Of Previously Rescinded Policies And Denied Claims	224,000,000				224,000,000				129,000,000
IBNR Reserve Estimate [Abstract]
Liability for Unpaid Claims and Claims Adjustment Expense, Incurred but Not Reported (IBNR) Claims, Amount	249,500,000				249,500,000				170,600,000
Claim Severity Detail [Abstract]
First Lien Primary Claim Severity	27.00%				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	91,000,000				91,000,000
First Lien Pool Claim Severity	45.00%				45.00%
Impact To Loss Reserves Based On One Percentage Change In Pool Claim Severity	5,000,000				5,000,000
Impact To Loss Reserves Based On One Percentage Change in Default To Claim Rate	58,000,000				58,000,000
Default To Claim Rate Assumptions Twelve Or More Missed Payments [Member]
Default To Claim Rate Detail [Abstract]
Number Of Payments Missed For Insured Loans	12				12
Default To Claim Rate Assumptions Two Missed Payments [Member]
Default To Claim Rate Detail [Abstract]
Number Of Payments Missed For Insured Loans	2				2
Default To Claim Rate Assumptions Three Missed Payments [Member]
Default To Claim Rate Detail [Abstract]
Number Of Payments Missed For Insured Loans	3				3
Smart Home [Member]
Liability For Unpaid Claims And Claims Adjustment Expense Activity In Liability [Line Items]
Number of Transactions Terminated	1				1
Deduct paid claims and LAE related to [Abstract]
Increase (Decrease) in Reinsurance Recoverable					$ 39,600,000

[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.