Note 5 - VIEs Financial Guaranty Insurance Contracts VIEs (Details) (USD $)	3 Months Ended		9 Months Ended					3 Months Ended		9 Months Ended				9 Months Ended					9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Sep. 30, 2013 Variable Interest Entity, Primary Beneficiary [Member] transaction	Jun. 30, 2012 April 2012 Commutation Transactions [Member] Radian Asset Assurance [Member] security counterparty transaction	Sep. 30, 2013 Financial Guaranty Segment	Sep. 30, 2012 Financial Guaranty Segment	Sep. 30, 2013 Financial Guaranty Segment	Sep. 30, 2012 Financial Guaranty Segment	Sep. 30, 2013 Financial Guaranty Segment Variable Interest Entity, Primary Beneficiary [Member]	Sep. 30, 2012 Financial Guaranty Segment Variable Interest Entity, Primary Beneficiary [Member]	Sep. 30, 2013 Financial Guarantee Insurance Product Line [Member] Variable Interest Entity, Primary Beneficiary [Member]		Sep. 30, 2012 Financial Guarantee Insurance Product Line [Member] Variable Interest Entity, Primary Beneficiary [Member]	Dec. 31, 2012 Financial Guarantee Insurance Product Line [Member] Variable Interest Entity, Primary Beneficiary [Member]		Sep. 30, 2013 Financial Guarantee Insurance Product Line [Member] Variable Interest Entity, Not Primary Beneficiary [Member]		Sep. 30, 2012 Financial Guarantee Insurance Product Line [Member] Variable Interest Entity, Not Primary Beneficiary [Member]	Dec. 31, 2012 Financial Guarantee Insurance Product Line [Member] Variable Interest Entity, Not Primary Beneficiary [Member]		Sep. 30, 2013 Financial Guarantee Insurance Product Line [Member] Financial Guaranty Segment	Jun. 30, 2013 Financial Guarantee Insurance Product Line [Member] Financial Guaranty Segment	Dec. 31, 2012 Financial Guarantee Insurance Product Line [Member] Financial Guaranty Segment	Sep. 30, 2012 Financial Guarantee Insurance Product Line [Member] Financial Guaranty Segment	Jun. 30, 2012 Financial Guarantee Insurance Product Line [Member] Financial Guaranty Segment	Dec. 31, 2011 Financial Guarantee Insurance Product Line [Member] Financial Guaranty Segment
Variable Interest Entity [Line Items]
Number of Derivative Counterparties Involved in Commutation							1
Number Of Trups CDOs Terminated							6
Net Par Outstanding							$ 699,000,000
Number Of Consolidated Other Financial Guaranty Transactions						2
Number Of Consolidated CDO Of ABS Transactions							1
Balance Sheet Related Disclosures
Variable Interest Entity Carrying Amount Of Other Invested Assets	79,749,000		79,749,000		78,006,000									79,749,000			78,006,000
Derivative assets	20,844,000		20,844,000		13,609,000														1,176,000			3,201,000
Premiums receivable																			2,290,000			2,859,000
VIE Other Assets	93,375,000		93,375,000		99,337,000									93,375,000			99,337,000		0			0
Unearned premiums	751,587,000		751,587,000		648,682,000			216,167,000	281,311,000	216,167,000	281,311,000								1,960,000			2,513,000
Reserve for losses and LAE	2,346,879,000		2,346,879,000		3,149,936,000														13,977,000			14,376,000		30,538,000	23,611,000	64,291,000	70,608,000	92,645,000	60,550,000
VIE Derivative Liabilities	68,040,000		68,040,000		70,467,000									68,040,000			70,467,000
Derivative liabilities	344,870,000		344,870,000		266,873,000			344,870,000	267,323,000	344,870,000	267,323,000								259,261,000			175,781,000
VIE debt—at fair value	104,218,000		104,218,000		108,858,000							93,109,000	100,203,000	93,109,000			98,983,000
VIE Accounts Payable And Other Liabilities	285,000		285,000		366,000									285,000			366,000
Maximum exposure (1)														123,849,000	[1]		120,939,000	[1]	4,748,667,000	[1]		5,096,718,000	[1]
Statement of Operations
Premiums earned	211,984,000	190,963,000	617,696,000	545,107,000				11,864,000	12,278,000	36,632,000	22,208,000								872,000		1,286,000
Net investment income	26,732,000	25,635,000	81,220,000	91,225,000				11,864,000	10,877,000	35,984,000	40,848,000			1,338,000		2,903,000
Gain (Loss) on Investments, Excluding Other than Temporary Impairments	(7,132,000)	84,659,000	(142,891,000)	178,537,000				(2,752,000)	41,280,000	(51,888,000)	76,318,000			405,000		(3,128,000)
Change in fair value of derivative instruments	10,778,000	(41,056,000)	(70,357,000)	(146,937,000)				10,778,000	(41,055,000)	(70,357,000)	(146,905,000)			513,000		1,253,000			(82,069,000)		(166,404,000)
Net gains (losses) on other financial instruments	902,000	(740,000)	(3,585,000)	(80,454,000)				1,070,000	1,220,000	(1,614,000)	(77,827,000)			3,377,000		(91,274,000)
Provision for losses, (decrease) increase	157,174,000	176,352,000	429,524,000	653,374,000				5,162,000	4,547,000	9,146,000	38,762,000								(208,000)		5,854,000
Other operating expenses	70,974,000	50,429,000	212,055,000	140,776,000				11,384,000	10,179,000	35,390,000	32,989,000			1,469,000		1,802,000
Net cash inflow for VIEs														$ 333,000		$ (134,600,000)			$ 4,133,000		$ (70,486,000)

[1] The difference between the carrying amounts of the net asset/liability position and maximum exposure related to VIEs is primarily due to the difference between the face amount of the obligation and the recorded fair values, which include an adjustment for our non-performance risk, as applicable. For those VIEs that have recourse to our general credit, the maximum exposure is based on the net par amount of our insured obligation. For any VIEs that do not have recourse to our general credit, the maximum exposure is generally based on the recorded net assets of the VIE, as of the reporting date.