Reinsurance and Other Monoline Exposures - Effect of Reinsurance on Statement of Operations (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Premiums Written:
Direct	$ 29		$ 31
Assumed	3	[1]	(1)	[1]
Ceded	0		(24)
Net	32		6
Premiums Earned:
Direct	148		140
Assumed	10		11
Ceded	(16)		(19)
Net earned premiums	142		132
Loss and LAE:
Direct	26		34
Assumed	(7)		6
Ceded	(1)		1
Loss and LAE	$ 18		$ 41

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