Financial Guaranty Insurance Premiums - Components of Unearned Premium Reserve (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012
Financial Guaranty Insurance Premiums [Line Items]
Deferred premium revenue, gross	$ 4,652		$ 5,356
Deferred premium revenue, ceded	470		586
Deferred premium revenue, net	4,182	[1]	4,770	[1]
Unearned premium reserve, gross	4,595		5,207
Unearned premium reserve, ceded	452		561
Unearned premium reserve, net	4,143	[1]	4,646	[1]
Total net unearned premium reserve related to FG VIE	187		262
Contra-paid related to FG and VIEs	55		98
Financial guaranty insurance
Financial Guaranty Insurance Premiums [Line Items]
Deferred premium revenue, gross	4,647		5,349
Deferred premium revenue, ceded	470		586
Deferred premium revenue, net	4,177	[1]	4,763	[1]
Contra-paid, gross	(57)		(149)
Contra-paid, ceded	(18)		(25)
Contra-paid, net	(39)	[1]	(124)	[1]
Other
Financial Guaranty Insurance Premiums [Line Items]
Unearned premium reserve, gross	5		7
Unearned premium reserve, ceded	0		0
Unearned premium reserve, net	$ 5	[1]	$ 7	[1]

[1] Excludes $187 million and $262 million deferred premium revenue and $55 million and $98 million contra-paid related to FG VIEs as of December 31, 2013 and December 31, 2012, respectively.