Note 3 - Segment Reporting Schedule of Segment Reporting Information by Segment (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Segment Reporting Information [Line Items]
Net premiums written—insurance	$ 686,630	$ 707,247	$ 691,881
Net premiums earned-insurance	738,982	756,025	825,733
Net investment income	114,337	163,520	178,760
Net gains on investments	184,888	202,177	139,944
Net impairment losses recognized in earnings	(3)	(1,202)	(90)
Change in fair value of derivative instruments	(144,025)	628,395	(558,712)
Net (losses) gains on other financial instruments	(82,269)	193,329	(211,681)
Gain on sale of affiliate	7,708	0	34,815
Other income	5,790	5,599	8,696
Total revenues	825,408	1,947,843	417,465
Provision for losses	959,171	1,296,521	1,739,244
Change in reserve for premium deficiency	41	(7,092)	(14,621)
Policy acquisition costs	61,876	52,763	53,469
Other operating expenses	196,672	175,810	191,942
Interest expense	51,832	61,394	41,777
Total expenses	1,269,592	1,579,396	2,011,811
Equity in net (loss) income of affiliates	(13)	65	14,668
Pretax (loss) income	(444,197)	368,512	(1,579,678)
Income tax provision	7,271	66,362	226,189
Net (loss) income	(451,468)	302,150	(1,805,867)
Cash and investments	5,208,199	5,846,168	6,680,630
Deferred policy acquisition costs	88,202	139,906	148,326
Total assets	5,903,200	6,656,765	7,620,887
Unearned premiums	648,682	637,372	686,364
Reserve for losses and LAE	3,149,936	3,310,902	3,596,735
VIE debt - at fair value	108,858	228,240	520,114
Derivative liabilities	266,873	126,006	723,579
New Insurance Written
Mortgage Insurance Segment
Segment Reporting Information [Line Items]
Net premiums written—insurance	806,305	717,264	699,909
Net premiums earned-insurance	702,385	680,895	739,631
Net investment income	63,191	93,678	104,030
Net gains on investments	103,666	126,205	84,004
Net impairment losses recognized in earnings	0	(1,202)	(90)
Change in fair value of derivative instruments	(330)	(632)	32,381
Net (losses) gains on other financial instruments	(3,491)	3,864	(48,137)
Gain on sale of affiliate	0		0
Other income	5,516	5,369	7,208
Total revenues	870,937	908,177	919,027
Provision for losses	921,507	1,293,857	1,730,801
Change in reserve for premium deficiency	41	(7,092)	(14,621)
Policy acquisition costs	34,131	36,051	36,102
Other operating expenses	152,448	132,225	141,172
Interest expense	7,454	13,894	11,668
Total expenses	1,115,581	1,468,935	1,905,122
Equity in net (loss) income of affiliates	0	0	0
Pretax (loss) income	(244,644)	(560,758)	(986,095)
Income tax provision	(30,045)	83,157	157,082
Net (loss) income	(214,599)	(643,915)	(1,143,177)
Cash and investments	3,118,153	3,210,279	4,037,578
Deferred policy acquisition costs	38,478	52,094	41,939
Total assets	3,575,427	3,470,103	4,801,953
Unearned premiums	382,413	233,446	197,260
Reserve for losses and LAE	3,083,608	3,247,900	3,524,971
VIE debt - at fair value	9,875	9,450	141,006
Derivative liabilities	0	0	0
New Insurance Written	37,061,000	15,510	11,558
Primary New Insurance Written Major Customer for Segment Reporting Percentage	6.20%	10.10%	15.50%
Entity Wide Revenue, Major Customer, Number of Customers	2	2
Entity-Wide Revenue, Major Customer, Percentage	10.00%	10.00%
Mortgage Insurance Segment | Geographic Concentration Risk [Member] | State Of California [Member]
Segment Reporting Information [Line Items]
Direct Primary New Insurance Written by Geographic Area Percent	17.10%	15.30%	12.80%
Mortgage Insurance Segment | Primary Risk In Force [Member] | Geographic Concentration Risk [Member] | State Of California [Member]
Segment Reporting Information [Line Items]
Concentration Risk, Percentage	12.80%	11.80%
Mortgage Insurance Segment | Pool Risk in Force [Member] | Geographic Concentration Risk [Member] | State Of California [Member]
Segment Reporting Information [Line Items]
Concentration Risk, Percentage	10.40%	10.50%
Financial Guaranty Segment
Segment Reporting Information [Line Items]
Net premiums written—insurance	(119,675)	(10,017)	(8,028)
Net premiums earned-insurance	36,597	75,130	86,102
Net investment income	51,146	69,842	74,730
Net gains on investments	81,222	75,972	55,940
Net impairment losses recognized in earnings	(3)	0	0
Change in fair value of derivative instruments	(143,695)	629,027	(591,093)
Net (losses) gains on other financial instruments	(78,778)	189,465	(163,544)
Gain on sale of affiliate	7,708		0
Other income	274	230	364
Total revenues	(45,529)	1,039,666	(537,501)
Provision for losses	37,664	2,664	8,443
Change in reserve for premium deficiency	0	0	0
Policy acquisition costs	27,745	16,712	17,367
Other operating expenses	44,224	43,585	50,520
Interest expense	44,378	47,500	30,109
Total expenses	154,011	110,461	106,439
Equity in net (loss) income of affiliates	(13)	65	78
Pretax (loss) income	(199,553)	929,270	(643,862)
Income tax provision	37,316	(16,795)	51,509
Net (loss) income	(236,869)	(946,065)	(695,371)
Cash and investments	2,090,046	2,635,889	2,643,052
Deferred policy acquisition costs	49,724	87,812	106,387
Total assets	2,327,773	3,186,662	2,818,934
Unearned premiums	266,269	403,926	489,104
Reserve for losses and LAE	66,328	63,002	71,764
VIE debt - at fair value	98,983	218,790	379,108
Derivative liabilities	266,873	126,006	723,579
Financial Services Segment
Segment Reporting Information [Line Items]
Net premiums written—insurance			0
Net premiums earned-insurance			0
Net investment income			0
Net gains on investments			0
Net impairment losses recognized in earnings			0
Change in fair value of derivative instruments			0
Net (losses) gains on other financial instruments			0
Gain on sale of affiliate			34,815
Other income			1,124
Total revenues			35,939
Provision for losses			0
Change in reserve for premium deficiency			0
Policy acquisition costs			0
Other operating expenses			250
Interest expense			0
Total expenses			250
Equity in net (loss) income of affiliates			14,590
Pretax (loss) income			50,279
Income tax provision			17,598
Net (loss) income			32,681
Cash and investments			0
Deferred policy acquisition costs			0
Total assets			0
Unearned premiums			0
Reserve for losses and LAE			0
VIE debt - at fair value			0
Derivative liabilities			$ 0
Minimum [Member] | Mortgage Insurance Segment | Primary Risk In Force [Member] | Geographic Concentration Risk [Member] | State Of California [Member]
Segment Reporting Information [Line Items]
Concentration Risk, Percentage	10.00%