Note 10 - Financial Guaranty Insurance Contracts Schedule of Significant Components Of Change In Financial Guaranty Claim Liability (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Financial Guaranty Segment [Member]
Claim liability at beginning of period	$ 92,600,000	$ 70,800,000	$ 60,500,000	$ 67,400,000
(Decrease)/increase in gross claim liability	37,600,000	15,000,000	199,300,000	56,700,000
Decrease/(increase) in gross potential recoveries	(69,600,000)	(50,700,000)	(261,300,000)	(83,900,000)
Decrease/(increase) in discount	36,400,000	8,400,000	102,500,000	2,600,000
(Increase)/decrease in unearned premiums	100,000	300,000	(1,800,000)	4,300,000
Incurred losses and LAE	4,500,000	(27,000,000)	38,700,000	(20,300,000)
Paid Losses and LAE Current Year	300,000	0	0	0
Paid Losses and LAE Prior Years	(26,800,000)	(2,300,000)	(28,600,000)	(5,600,000)
Paid losses and LAE	(26,500,000)	(2,300,000)	(28,600,000)	(5,600,000)
Claim liability at end of period	70,600,000	41,500,000	70,600,000	41,500,000
Components of incurred losses and LAE [Abstract]
Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims Current Year	8,700,000	1,000,000	8,800,000	1,000,000
Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims, Prior Years	(4,200,000)	(28,000,000)	29,900,000	(21,300,000)
Total incurred	4,500,000	(27,000,000)	38,700,000	(20,300,000)
Components of (decrease)/increase in discount [Abstract]
Decrease/(increase) in discount related to claim liabilities established in current period	36,100,000	1,200,000	101,800,000	1,100,000
Decrease/(increase) in discount related to existing claim liabilites	300,000	7,200,000	700,000	1,500,000
Total decrease/(increase) in discount	36,400,000	8,400,000	102,500,000	2,600,000
Project Finance Credit [Member]
Components of (decrease)/increase in discount [Abstract]
Net Par Outstanding	70,000,000		70,000,000
Greece [Member]
Components of (decrease)/increase in discount [Abstract]
Statutory Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid	23,500,000
Radian Asset Assurance [Member] | Greece [Member]
Components of (decrease)/increase in discount [Abstract]
Statutory Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid	$ 23,500,000