Note 4 - Fair Value of Financial Instruments Fair Value Assets Liabilities by Hierarchy Level (Details) (USD $)	Sep. 30, 2011		Dec. 31, 2010
Fair Value by Hierarchy Level Assets and Liabilities
Derivative Assets	$ 20,315,000		$ 26,212,000
Derivative liabilities	188,921,000		723,579,000
VIE debt	273,379,000		520,114,000
Fixed-maturities held to maturity	4,248,000		11,416,000
Fair Value, Inputs, Level 1 | US government and agency securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	405,100,000		1,075,000,000
Fair Value, Inputs, Level 1 | State and municipal obligations | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	0		0
Fair Value, Inputs, Level 1 | Money market instruments | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	499,000,000		310,900,000
Fair Value, Inputs, Level 1 | Corporate bonds and notes | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	0		0
Fair Value, Inputs, Level 1 | RMBS | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	0		0
Fair Value, Inputs, Level 1 | CMBS | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	0		0
Fair Value, Inputs, Level 1 | CDO | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	0		0
Fair Value, Inputs, Level 1 | Other ABS | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	0		0
Fair Value, Inputs, Level 1 | Foreign government securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	0		0
Fair Value, Inputs, Level 1 | Hybrid securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	0		0
Fair Value, Inputs, Level 1 | Equity securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	149,100,000	[1]	168,400,000	[1]
Fair Value, Inputs, Level 1 | Other investments | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	0	[2]	0	[3]
Fair Value, Inputs, Level 1 | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	1,053,200,000	[4]	1,554,300,000	[5]
Derivative Assets	0		0
Other Assets	0	[6]	0	[6]
Total Assets at Fair Value	1,053,200,000		1,554,300,000
Derivative liabilities	0		0
VIE debt	0	[7]	0	[8]
Total Liabilities at Fair Value	0		0
Fair Value, Inputs, Level 2 | US government and agency securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	737,200,000		731,400,000
Fair Value, Inputs, Level 2 | State and municipal obligations | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	1,066,700,000		1,159,700,000
Fair Value, Inputs, Level 2 | Money market instruments | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	0		0
Fair Value, Inputs, Level 2 | Corporate bonds and notes | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	766,700,000		1,060,400,000
Fair Value, Inputs, Level 2 | RMBS | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	983,000,000		913,500,000
Fair Value, Inputs, Level 2 | CMBS | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	189,000,000		173,600,000
Fair Value, Inputs, Level 2 | CDO | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	0		0
Fair Value, Inputs, Level 2 | Other ABS | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	112,400,000		131,100,000
Fair Value, Inputs, Level 2 | Foreign government securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	100,400,000		83,500,000
Fair Value, Inputs, Level 2 | Hybrid securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	324,600,000		318,900,000
Fair Value, Inputs, Level 2 | Equity securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	169,200,000	[1]	168,600,000	[1]
Fair Value, Inputs, Level 2 | Other investments | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	151,600,000	[2]	150,000,000	[3]
Fair Value, Inputs, Level 2 | Committed Preferred Securities CPS | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	150,000,000
Fair Value, Inputs, Level 2 | Short Term CDs | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	1,600,000
Fair Value, Inputs, Level 2 | Lottery Annuities
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value			2,600,000
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	4,600,800,000	[4]	4,890,700,000	[5]
Derivative Assets	300,000		0
Other Assets	0	[6]	0	[6]
Total Assets at Fair Value	4,601,100,000		4,890,700,000
Derivative liabilities	0		0
VIE debt	0	[7]	0	[8]
Total Liabilities at Fair Value	0		0
Fair Value, Inputs, Level 3
Fair Value by Hierarchy Level Assets and Liabilities
Total Level III Assets	4.80%
Total Level III Liabilities	100.00%
Number Of Consolidated Other Financial Guaranty Transactions	2		2
Fair Value, Inputs, Level 3 | US government and agency securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	0		0
Fair Value, Inputs, Level 3 | State and municipal obligations | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	62,600,000		23,200,000
Fair Value, Inputs, Level 3 | Money market instruments | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	0		0
Fair Value, Inputs, Level 3 | Corporate bonds and notes | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	0		0
Fair Value, Inputs, Level 3 | RMBS | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	48,800,000		52,500,000
Fair Value, Inputs, Level 3 | CMBS | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	38,000,000		23,000,000
Fair Value, Inputs, Level 3 | CDO | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	5,400,000		2,400,000
Fair Value, Inputs, Level 3 | Other ABS | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	2,700,000		3,300,000
Fair Value, Inputs, Level 3 | Foreign government securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	0		0
Fair Value, Inputs, Level 3 | Hybrid securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	0		0
Fair Value, Inputs, Level 3 | Equity securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	2,800,000	[1]	2,900,000	[1]
Fair Value, Inputs, Level 3 | Other investments | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	6,200,000	[2]	4,600,000	[3]
Fair Value, Inputs, Level 3 | Lottery Annuities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	1,700,000
Fair Value, Inputs, Level 3 | Consolidated Committed Preferred Custodial Trust Securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	4,500,000		2,000,000
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	166,500,000	[4]	111,900,000	[5]
Derivative Assets	20,000,000		26,200,000
Other Assets	96,800,000	[6]	109,700,000	[6]
Total Assets at Fair Value	283,300,000		247,800,000
Derivative liabilities	188,900,000		723,600,000
VIE debt	273,400,000		520,100,000
Total Liabilities at Fair Value	462,300,000		1,243,700,000
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring | NIMS [Member]
Fair Value by Hierarchy Level Assets and Liabilities
VIE debt	31,200,000		141,000,000
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring | Consolidated Financial Guaranty Insurance Contracts [Member]
Fair Value by Hierarchy Level Assets and Liabilities
VIE debt	242,200,000		379,100,000
US government and agency securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	1,142,300,000		1,806,400,000
State and municipal obligations | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	1,129,300,000		1,182,900,000
Money market instruments | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	499,000,000		310,900,000
Corporate bonds and notes | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	766,700,000		1,060,400,000
RMBS | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	1,031,800,000		966,000,000
CMBS | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	227,000,000		196,600,000
CDO | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	5,400,000		2,400,000
Other ABS | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	115,100,000		134,400,000
Foreign government securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	100,400,000		83,500,000
Hybrid securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	324,600,000		318,900,000
Equity securities | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	321,100,000	[1]	339,900,000	[1]
Other investments | Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	157,800,000	[2]	154,600,000	[3]
Fair Value, Measurements, Recurring
Fair Value by Hierarchy Level Assets and Liabilities
Total Investments at Fair Value	5,820,500,000	[4]	6,556,900,000	[5]
Derivative Assets	20,300,000		26,200,000
Other Assets	96,800,000	[6]	109,700,000	[6]
Total Assets at Fair Value	5,937,600,000		6,692,800,000
Derivative liabilities	188,900,000		723,600,000
VIE debt	273,400,000	[7]	520,100,000	[8]
Total Liabilities at Fair Value	462,300,000		1,243,700,000
Fair Value, Measurements, Recurring | Carrying (Reported) Amount, Fair Value Disclosure [Member]
Fair Value by Hierarchy Level Assets and Liabilities
Fixed-maturities held to maturity	4,100,000		10,800,000
Short Term Investments (Carried at Cost) Fair Value Disclosure	0		1,600,000
Other invested assets fair value disclosure	62,400,000		59,600,000
Consolidated Financial Guaranty Insurance Contracts [Member]
Fair Value by Hierarchy Level Assets and Liabilities
Derivative Assets	0		0
Derivative liabilities	20,800,000		19,200,000
VIE debt	$ 242,200,000		$ 379,100,000
Number Of Consolidated Other Financial Guaranty Transactions	2

[1] Comprising broadly diversified domestic equity mutual funds included within Level I and various preferred and common stocks invested across numerous companies and industries included within Levels II and III.

[2] Comprising short-term commercial paper within CPS trusts ($150.0 million) and short-term CDs ($1.6 million) included within Level II, and lottery annuities ($1.7 million) and TruPs held by consolidated VIEs ($4.5 million) included within Level III.

[3] Comprising short-term commercial paper within CPS trusts included within Level II, and lottery annuities ($2.6 million) and TruPs held by consolidated VIEs ($2.0 million) included within Level III.

[4] Does not include fixed-maturities held to maturity ($4.1 million) and other invested assets ($62.4 million), primarily invested in limited partnerships, accounted for as cost-method investments and not measured at fair value.

[5] Does not include fixed-maturities held to maturity ($10.8 million), certain short-term investments ($1.6 million), primarily invested in CDs and time deposits, and other invested assets ($59.6 million), primarily invested in limited partnerships, accounted for as cost-method investments and not measured at fair value.

[6] Comprising manufactured housing loan collateral related to two consolidated financial guaranty VIEs.

[7] Comprising consolidated debt related to NIMS VIEs ($31.2 million) and amounts related to financial guaranty VIEs ($242.2 million).

[8] Comprising consolidated debt related to NIMS VIEs ($141.0 million) and amounts related to financial guaranty VIEs ($379.1 million) that required consolidation as of January 1, 2010, under the accounting standard update regarding improvements to financial reporting by enterprises involving VIEs.