Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Premiums written—insurance:
Direct	$ 892,983	$ 755,758	$ 788,321
Assumed	(88,991)	(11,162)	(6,585)
Ceded	(117,362)	(37,349)	(89,855)
Net premiums written	686,630	707,247	691,881
Decrease in unearned premiums	52,352	48,778	133,852
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
Total other-than-temporary impairment ('OTTI') losses	(3)	(1,202)	(90)
Losses recognized in other comprehensive income (loss)	0	0	0
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
Expenses:
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)
Basic net (loss) income per share	$ (3.41)	$ 2.28	$ (15.74)
Diluted net (loss) income per share	$ (3.41)	$ 2.26	$ (15.74)
Weighted-average number of common shares outstanding—basic	132,533	132,372	114,697
Weighted-average number of common and common equivalent shares outstanding—diluted	132,533	133,863	114,697
Dividends per share	$ 0.01	$ 0.01	$ 0.01