Reinsurance and Other Monoline Exposures - Effect of Reinsurance on Statement of Operations (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Exposure, Premium Receivable, and Loss and LAE by Reinsurer
Increase in net par due to commutations					$ 856
Premiums Written:
Direct	52		28		100		48
Assumed	(5)	[1]	(2)	[1]	(6)	[1]	17	[1]
Ceded	0	[2]	4	[2]	(22)	[2]	3	[2]
Net	47		30		72		68
Premiums Earned:
Direct	151		173		438		627
Assumed	12		12		32		26
Ceded	(19)		(26)		(58)		(83)
Net earned premiums	144	[3]	159	[3]	412	[3]	570	[3]
Loss and LAE:
Direct	(58)		25		46		18
Assumed	11		35		26		70
Ceded	3		(5)		(18)		(19)
Loss and LAE	(44)		55		54		69
AG Re
Exposure, Premium Receivable, and Loss and LAE by Reinsurer
Fair market value of company's pledged securities	288				288
AGC
Exposure, Premium Receivable, and Loss and LAE by Reinsurer
Fair market value of company's pledged securities	$ 50				$ 50

[1] Negative assumed premiums written were due to changes in expected Debt Service schedules.

[2] Positive ceded premiums written were due to changes in expected Debt Service schedules.

[3] Excludes $5 million and $14 million for Third Quarter 2014 and 2013, respectively, and $27 million and $47 million for Nine Months 2014 and 2013, respectively, related to consolidated FG VIEs.