Note 5 - Fair Value of Financial Instruments Fair Value, Measurement Inputs Disclosure (Details) (USD $)																																																																																								12 Months Ended
	Dec. 31, 2013 contract	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Consolidated Financial Guaranty Insurance Contracts [Member] Fair Value, Inputs, Level 3	Dec. 31, 2013 CDOS of commercial mortgage backed securities (CMBS)[Member]	Dec. 31, 2013 Non Corporate Collateralized Debt Obligations And Other Derivative Transactions [Member]	Dec. 31, 2013 Corporate collateralized debt obligations (CDO's)[Member]	Dec. 31, 2013 Base Correlation Model Valuation Technique [Member] Corporate collateralized debt obligations (CDO's)[Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Base Correlation Model Valuation Technique [Member] Corporate collateralized debt obligations (CDO's)[Member] Fair Value, Inputs, Level 3		Dec. 31, 2013 Base Correlation Model Valuation Technique [Member] Maximum [Member] Corporate collateralized debt obligations (CDO's)[Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Base Correlation Model Valuation Technique [Member] Maximum [Member] Corporate collateralized debt obligations (CDO's)[Member] Fair Value, Inputs, Level 3	Dec. 31, 2013 Base Correlation Model Valuation Technique [Member] Minimum [Member] Corporate collateralized debt obligations (CDO's)[Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Base Correlation Model Valuation Technique [Member] Minimum [Member] Corporate collateralized debt obligations (CDO's)[Member] Fair Value, Inputs, Level 3	Dec. 31, 2013 Base Correlation Model Valuation Technique [Member] Weighted Average [Member] Corporate collateralized debt obligations (CDO's)[Member] Fair Value, Inputs, Level 3	Dec. 31, 2012 Base Correlation Model Valuation Technique [Member] Weighted Average [Member] Corporate collateralized debt obligations (CDO's)[Member] Fair Value, Inputs, Level 3	Dec. 31, 2012 Base Correlation Model Valuation Technique [Member] Less Than [Member] Minimum [Member] Corporate collateralized debt obligations (CDO's)[Member] Fair Value, Inputs, Level 3	Dec. 31, 2013 Discounted Cash Flow Valuation Technique [Member] US States and Political Subdivisions Debt Securities [Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] US States and Political Subdivisions Debt Securities [Member] Fair Value, Inputs, Level 3		Dec. 31, 2013 Discounted Cash Flow Valuation Technique [Member] Other investments Fair Value, Inputs, Level 3		Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] Other investments Fair Value, Inputs, Level 3		Dec. 31, 2013 Discounted Cash Flow Valuation Technique [Member] Collateralized Debt Obligation of Commercial Mortgage Backed Securities [Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] Collateralized Debt Obligation of Commercial Mortgage Backed Securities [Member] Fair Value, Inputs, Level 3		Dec. 31, 2013 Discounted Cash Flow Valuation Technique [Member] TruPs Collateralized Debt Obligation [Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] TruPs Collateralized Debt Obligation [Member] Fair Value, Inputs, Level 3		Dec. 31, 2013 Discounted Cash Flow Valuation Technique [Member] TruPs-Related VIE [Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] TruPs-Related VIE [Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] NIMS Derivatives Fair Value, Inputs, Level 3		Dec. 31, 2013 Discounted Cash Flow Valuation Technique [Member] NIMS VIEs [Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] NIMS VIEs [Member] Fair Value, Inputs, Level 3		Dec. 31, 2013 Discounted Cash Flow Valuation Technique [Member] Maximum [Member] Collateralized Debt Obligation of Commercial Mortgage Backed Securities [Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] Maximum [Member] Collateralized Debt Obligation of Commercial Mortgage Backed Securities [Member] Fair Value, Inputs, Level 3	Dec. 31, 2013 Discounted Cash Flow Valuation Technique [Member] Maximum [Member] TruPs Collateralized Debt Obligation [Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] Maximum [Member] TruPs Collateralized Debt Obligation [Member] Fair Value, Inputs, Level 3	Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] Maximum [Member] NIMS VIEs [Member] Fair Value, Inputs, Level 3		Dec. 31, 2013 Discounted Cash Flow Valuation Technique [Member] Minimum [Member] Collateralized Debt Obligation of Commercial Mortgage Backed Securities [Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] Minimum [Member] Collateralized Debt Obligation of Commercial Mortgage Backed Securities [Member] Fair Value, Inputs, Level 3	Dec. 31, 2013 Discounted Cash Flow Valuation Technique [Member] Minimum [Member] TruPs Collateralized Debt Obligation [Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] Minimum [Member] TruPs Collateralized Debt Obligation [Member] Fair Value, Inputs, Level 3	Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] Minimum [Member] NIMS VIEs [Member] Fair Value, Inputs, Level 3		Dec. 31, 2013 Discounted Cash Flow Valuation Technique [Member] Weighted Average [Member] US States and Political Subdivisions Debt Securities [Member] Fair Value, Inputs, Level 3	Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] Weighted Average [Member] US States and Political Subdivisions Debt Securities [Member] Fair Value, Inputs, Level 3	Dec. 31, 2013 Discounted Cash Flow Valuation Technique [Member] Weighted Average [Member] Other investments Fair Value, Inputs, Level 3	Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] Weighted Average [Member] Other investments Fair Value, Inputs, Level 3	Dec. 31, 2013 Discounted Cash Flow Valuation Technique [Member] Weighted Average [Member] TruPs Collateralized Debt Obligation [Member] Fair Value, Inputs, Level 3	Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] Weighted Average [Member] TruPs Collateralized Debt Obligation [Member] Fair Value, Inputs, Level 3	Dec. 31, 2013 Discounted Cash Flow Valuation Technique [Member] Weighted Average [Member] TruPs-Related VIE [Member] Fair Value, Inputs, Level 3	Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] Weighted Average [Member] TruPs-Related VIE [Member] Fair Value, Inputs, Level 3	Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] Weighted Average [Member] NIMS Derivatives Fair Value, Inputs, Level 3		Dec. 31, 2013 Discounted Cash Flow Valuation Technique [Member] Weighted Average [Member] NIMS VIEs [Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Discounted Cash Flow Valuation Technique [Member] Weighted Average [Member] NIMS VIEs [Member] Fair Value, Inputs, Level 3	Dec. 31, 2013 Risk-Based Model Valuation Technique [Member] Non Corporate Collateralized Debt Obligations And Other Derivative Transactions [Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Risk-Based Model Valuation Technique [Member] Non Corporate Collateralized Debt Obligations And Other Derivative Transactions [Member] Fair Value, Inputs, Level 3		Dec. 31, 2013 Risk-Based Model Valuation Technique [Member] Maximum [Member] Non Corporate Collateralized Debt Obligations And Other Derivative Transactions [Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Risk-Based Model Valuation Technique [Member] Maximum [Member] Non Corporate Collateralized Debt Obligations And Other Derivative Transactions [Member] Fair Value, Inputs, Level 3	Dec. 31, 2013 Risk-Based Model Valuation Technique [Member] Minimum [Member] Non Corporate Collateralized Debt Obligations And Other Derivative Transactions [Member] Fair Value, Inputs, Level 3		Dec. 31, 2012 Risk-Based Model Valuation Technique [Member] Minimum [Member] Non Corporate Collateralized Debt Obligations And Other Derivative Transactions [Member] Fair Value, Inputs, Level 3	Dec. 31, 2013 Risk-Based Model Valuation Technique [Member] Less Than [Member] Minimum [Member] Non Corporate Collateralized Debt Obligations And Other Derivative Transactions [Member] Fair Value, Inputs, Level 3	Dec. 31, 2012 Risk-Based Model Valuation Technique [Member] Less Than [Member] Minimum [Member] Non Corporate Collateralized Debt Obligations And Other Derivative Transactions [Member] Fair Value, Inputs, Level 3	Dec. 31, 2013 Fair Value, Measurements, Recurring		Dec. 31, 2012 Fair Value, Measurements, Recurring		Dec. 31, 2013 Fair Value, Measurements, Recurring Fair Value, Inputs, Level 3		Dec. 31, 2012 Fair Value, Measurements, Recurring Fair Value, Inputs, Level 3		Dec. 31, 2013 Fair Value, Measurements, Recurring Consolidated Financial Guaranty Insurance Contracts [Member] Fair Value, Inputs, Level 3	Dec. 31, 2012 Fair Value, Measurements, Recurring Consolidated Financial Guaranty Insurance Contracts [Member] Fair Value, Inputs, Level 3	Dec. 31, 2013 Fair Value, Measurements, Recurring NIMS VIEs [Member] Fair Value, Inputs, Level 3	Dec. 31, 2012 Fair Value, Measurements, Recurring NIMS VIEs [Member] Fair Value, Inputs, Level 3	Dec. 31, 2013 Fair Value, Measurements, Recurring US States and Political Subdivisions Debt Securities [Member]	Dec. 31, 2012 Fair Value, Measurements, Recurring US States and Political Subdivisions Debt Securities [Member]	Dec. 31, 2013 Fair Value, Measurements, Recurring US States and Political Subdivisions Debt Securities [Member] Fair Value, Inputs, Level 3	Dec. 31, 2012 Fair Value, Measurements, Recurring US States and Political Subdivisions Debt Securities [Member] Fair Value, Inputs, Level 3	Dec. 31, 2013 Fair Value, Measurements, Recurring Other investments		Dec. 31, 2012 Fair Value, Measurements, Recurring Other investments		Dec. 31, 2013 Fair Value, Measurements, Recurring Other investments Fair Value, Inputs, Level 3		Dec. 31, 2012 Fair Value, Measurements, Recurring Other investments Fair Value, Inputs, Level 3
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value, Transfers Between Level 1 And Level 2, Amount																																																																																								$ 0		$ 0
Number of Financial Guarantee Insurance Contracts That Require Posting of Collateral	4
Investments, Fair Value Disclosure																					18,700,000	[1]	19,000,000	[1]	81,000,000	[1]	78,000,000	[1]																																																												4,883,400,000	[2]	5,103,000,000	[3]	101,500,000	[2]	100,700,000	[3]					621,000,000	688,000,000	18,700,000	19,000,000	83,700,000	[4]	81,500,000	[5]	81,500,000	[4]	79,000,000	[5]
Fair Value, Measurement with Unobservable Inputs, Additional Disclosure, Discount Rate																																																															12.30%	8.80%	1.20%	1.90%			13.10%	13.40%
Fair Value, Measurement with Unobservable Inputs, Additional Disclosure, Expected Loss Rate																																																															11.10%	19.00%
Derivative Assets	16,642,000	13,609,000																																																																																						16,600,000		13,600,000		6,300,000		13,600,000
Fair Value, Measurement with Unobservable Inputs, Additional Disclosure, Correlation Factor																		85.00%	85.00%
Fair Value, Measurement with Unobservable Inputs, Additional Disclosure, CDS Spread Percent												4.30%	[6]	9.10%	0.80%	[6]	8.00%																														4.30%	[6]	9.10%	4.30%	[6]	9.10%	10.90%	[6]	0.80%	[6]	8.00%	0.80%	[6]	8.00%	8.50%	[6]									8.50%	[6]	7.90%	[6]						4.30%	[6]	9.10%	0.80%	[6]	8.00%
Derivative Assets (Liabilities), at Fair Value, Net					(67,777,000)	(221,777,000)	(1,361,000)	(1,400,000)	[1]	2,800,000	[1]																		(67,800,000)	[1]	(74,700,000)	[1]	(43,900,000)	[1]	(11,100,000)	[1]					1,600,000	[1]																																		(119,400,000)	[1]	(101,400,000)	[1]
Variable Interest Entity, Consolidated, Fair Value, Net Asset (Liability)																																					(68,400,000)	[1]	(70,400,000)	[1]			(2,800,000)	[1]	(9,900,000)	[1]
Fair Value, Measurement with Unobservable Inputs, Additional Disclosure, Average Credit Spread												0.90%		2.70%	0.10%					0.10%
Derivative, Expected Remaining Life																																																																																20 years		20 years				1 year	1 year
Fair Value, Measurement with Unobservable Inputs, Additional Disclosure, Correlation Factor Related to Vintage and Credit Rating																																															85.00%		85.00%						72.00%		72.00%
Fair Value, Measurement with Unobservable Inputs, Additional Disclosure, Principal Recovery Rate																																																																			75.00%	65.00%
Fair Value, Measurement with Unobservable Inputs, Additional Disclosure, Principal Recovery Rate Using Distressed Pricing Scenario																																																																			65.00%	60.00%
Fair Value, Measurement with Unobservable Inputs, Additional Disclosure, Probability of Paying a Conditional Liquidity Claim																																																		12.40%		36.70%						1.10%		0.80%
Fair Value, Measurement with Unobservable Inputs, Additional Disclosure, NIMS Spread																																																																							44.00%		43.80%		43.70%
VIE debt - at fair value	94,645,000	108,858,000	228,240,000	91,800,000																																																																																				94,600,000	[7]	108,900,000	[8]	94,600,000	[7]	108,900,000	[8]	91,800,000	99,000,000	2,800,000	9,900,000
Derivative liabilities	$ 307,185,000	$ 266,873,000	$ 126,006,000																																																																																					$ 307,200,000		$ 266,900,000		$ 307,200,000		$ 266,900,000

[1] Excludes certain assets and liabilities for which we do not develop quantitative unobservable inputs. The fair value estimates for these assets and liabilities are developed using third-party pricing information, generally without adjustment.

[2] Does not include fixed-maturities held to maturity ($0.4 million) and certain other invested assets ($47.4 million), primarily invested in limited partnerships, accounted for as cost-method investments and not measured at fair value.

[3] Does not include fixed-maturities held to maturity ($0.7 million) and certain other invested assets ($48.7 million), primarily invested in limited partnerships, accounted for as cost-method investments and not measured at fair value.

[4] Comprising TruPs ($0.6 million) and short-term CDs ($1.6 million) included within Level II and lottery annuities ($0.3 million), TruPs ($0.2 million), and a guaranteed investment contract held by a consolidated VIE ($81.0 million) within Level III.

[5] Comprising TruPs ($0.9 million) and short-term CDs ($1.6 million ) included within Level II and lottery annuities ($1.0 million) and guaranteed investment contract held by a consolidated VIE ($78.0 million) within Level III.

[6] Represents the range of our CDS spread that a typical market participant might use in the valuation analysis based on the remaining term of the investment.

[7] Comprising consolidated debt related to NIMS VIEs ($2.8 million) and amounts related to financial guaranty VIEs ($91.8 million).

[8] Comprising consolidated debt related to NIMS VIEs ($9.9 million) and amounts related to financial guaranty VIEs ($99.0 million).