Note 9 - Financial Guaranty Insurance Contracts Future Premium Revenues For Financial Guaranty Contracts (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012
Financial Guarantee Insurance Contracts, Future Expected Premium Revenue to be Recognized During First Quarter Following Balance Sheet Date [Member]
Future Premium Revenue To Be Recognized [Line Items]
Unearned premiums	$ 284.0
Amortization of Unearned Premium	6.4
Accretion of premium receivable	0.3
Total Premium Revenue to be recognized	6.7
Financial Guarantee Insurance Contracts, Future Expected Premium Revenue to be Recognized During Second Quarter Following Balance Sheet Date [Member]
Future Premium Revenue To Be Recognized [Line Items]
Unearned premiums	277.2
Amortization of Unearned Premium	6.8
Accretion of premium receivable	0.3
Total Premium Revenue to be recognized	7.1
Financial Guarantee Insurance Contracts, Future Expected Premium Revenue to be Recognized During Third Quarter Following Balance Sheet Date [Member]
Future Premium Revenue To Be Recognized [Line Items]
Unearned premiums	271.0
Amortization of Unearned Premium	6.2
Accretion of premium receivable	0.2
Total Premium Revenue to be recognized	6.4
2012 [Member]
Future Premium Revenue To Be Recognized [Line Items]
Unearned premiums	271.0
Amortization of Unearned Premium	19.4
Accretion of premium receivable	0.8
Total Premium Revenue to be recognized	20.2
2013 [Member]
Future Premium Revenue To Be Recognized [Line Items]
Unearned premiums	244.8
Amortization of Unearned Premium	26.2
Accretion of premium receivable	0.9
Total Premium Revenue to be recognized	27.1
2014 [Member]
Future Premium Revenue To Be Recognized [Line Items]
Unearned premiums	221.0
Amortization of Unearned Premium	23.8
Accretion of premium receivable	0.8
Total Premium Revenue to be recognized	24.6
2015 [Member]
Future Premium Revenue To Be Recognized [Line Items]
Unearned premiums	200.2
Amortization of Unearned Premium	20.8
Accretion of premium receivable	0.8
Total Premium Revenue to be recognized	21.6
2016 [Member]
Future Premium Revenue To Be Recognized [Line Items]
Unearned premiums	181.4
Amortization of Unearned Premium	18.8
Accretion of premium receivable	0.7
Total Premium Revenue to be recognized	19.5
2012 - 2016 [Member]
Future Premium Revenue To Be Recognized [Line Items]
Unearned premiums	181.4
Amortization of Unearned Premium	109.0
Accretion of premium receivable	4.0
Total Premium Revenue to be recognized	113.0
2017 - 2021 [Member]
Future Premium Revenue To Be Recognized [Line Items]
Unearned premiums	104.1
Amortization of Unearned Premium	77.3
Accretion of premium receivable	2.8
Total Premium Revenue to be recognized	80.1
2022 - 2026 [Member]
Future Premium Revenue To Be Recognized [Line Items]
Unearned premiums	52.1
Amortization of Unearned Premium	52.0
Accretion of premium receivable	1.8
Total Premium Revenue to be recognized	53.8
2027 - 2031 [Member]
Future Premium Revenue To Be Recognized [Line Items]
Unearned premiums	22.4
Amortization of Unearned Premium	29.7
Accretion of premium receivable	1.1
Total Premium Revenue to be recognized	30.8
After 2031 [Member]
Future Premium Revenue To Be Recognized [Line Items]
Unearned premiums	0
Amortization of Unearned Premium	22.4
Accretion of premium receivable	1.4
Total Premium Revenue to be recognized	23.8
Total Financial Guarantee Insurance Contracts Future Premium Revenue to be Recognized [Member]
Future Premium Revenue To Be Recognized [Line Items]
Unearned premiums	0
Amortization of Unearned Premium	290.4
Accretion of premium receivable	11.1
Total Premium Revenue to be recognized	$ 301.5