Consolidated Statements Of Operations (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Premiums earned:
Premiums earned (net of ceded premiums of $10, $14 and $12)	$ 457		$ 605		$ 605
Change in fair value of insured derivatives:
Unrealized gains (losses) on insured derivatives	1,777		1,870		(441)
Net change in fair value of insured derivatives	232		1,464		(2,812)
Net gains (losses) on financial instruments at fair value and foreign exchange	69		55		(99)
Investment losses related to other-than-temporary impairments:
Net investment losses related to other-than-temporary impairments	0		(105)		(101)
Net gains (losses) on extinguishment of debt	60		0		26
Other net realized gains (losses)	(29)		7		(1)
Total revenues	1,209		2,435		(1,557)
Expenses:
Losses and loss adjustment	117		50		(80)
Interest	236		284		300
Total expenses	793		837		682
Income (loss) before income taxes	416		1,598		(2,239)
Provision (benefit) for income taxes	166		364		(920)
Net income (loss)	250		1,234		(1,319)
Net income (loss) per common share:
Net income (loss) per basic common share	$ 1.30		$ 6.36		$ (6.85)	[1]
Net income (loss) per diluted common share	$ 1.29		$ 6.33		$ (6.85)	[1]
Weighted average number of common shares outstanding:
Basic	189,071,011	[2]	188,834,626	[1],[2]	192,505,045	[1],[2]
Diluted	190,312,913		189,897,021	[1]	192,505,045	[1]
Non Variable Interest Entity [Member]
Premiums earned:
Scheduled premiums earned	304		372		456
Refunding premiums earned	153		233		149
Premiums earned (net of ceded premiums of $10, $14 and $12)	457		605		605
Net investment income	166		214		383
Fees and reimbursements	21		61		50
Change in fair value of insured derivatives:
Realized gains (losses) and other settlements on insured derivatives	(1,545)		(406)		(2,371)
Unrealized gains (losses) on insured derivatives	1,777		1,870		(441)
Net change in fair value of insured derivatives	232		1,464		(2,812)
Net gains (losses) on financial instruments at fair value and foreign exchange	69		55		(99)
Investment losses related to other-than-temporary impairments:
Investment losses related to other-than-temporary impairments	0		(58)		(125)
Other-than-temporary impairments recognized in accumulated other comprehensive income (loss)	0		(47)		24
Net investment losses related to other-than-temporary impairments	0		(105)		(101)
Net gains (losses) on extinguishment of debt	60		0		26
Other net realized gains (losses)	(29)		7		(1)
Expenses:
Losses and loss adjustment	117		50		(80)
Amortization of deferred acquisition costs	46		50		63
Operating	338		381		308
Interest	236		284		300
Variable Interest Entity Primary Beneficiary [Member]
Premiums earned:
Net investment income	56		67		70
Change in fair value of insured derivatives:
Net gains (losses) on financial instruments at fair value and foreign exchange	175		18		59
Investment losses related to other-than-temporary impairments:
Net gains (losses) on extinguishment of debt	1		49		0
Other net realized gains (losses)	1		0		263
Expenses:
Operating	11		17		29
Interest	$ 45		$ 55		$ 62

[1] Amounts shown are revised.

[2] Includes 629,896, 506,714 and 565,819 of participating securities that met the service condition and were eligible to receive nonforfeitable dividends or dividend equivalents for the years ended December 31, 2013, 2012 and 2011, respectively.