Consolidated Variable Interest Entities - Effect of Consolidating FG VIE's on Financial Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Variable Interest Entity [Line Items]
Net earned premiums	$ 219	$ 136	$ 361	$ 268
Net investment income	98	96	199	199
Net realized investment gains (losses)	(9)	(8)	7	(6)
Fair value gains (losses) on FG VIEs	5	25	(2)	182
Other income (loss)	55	7	46	28
Loss and LAE	188	57	206	98
Income (loss) before income taxes	409	218	675	287
Provision (benefit) for income taxes	112	59	177	86
Net income (loss)	297	159	498	201
Net cash flows provided by (used in) operating activities			105	222
Effect on shareholders’ equity (decrease) increase	5,806		5,806		$ 5,758
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Net earned premiums	(5)	(5)	(10)	(22)
Net investment income	(3)	(3)	(6)	(6)
Net realized investment gains (losses)	3	(5)	3	(5)
Fair value gains (losses) on FG VIEs	5	25	(2)	182
Bargain purchase gain and settlement of pre-existing relationships resulting from Radian Asset Acquisition, after-tax	2	0	2	0
Other income (loss)	0	0	0	(2)
Loss and LAE	2	8	7	7
Income (loss) before income taxes	4	20	(6)	154
Provision (benefit) for income taxes	1	7	(3)	54
Net income (loss)	3	13	(3)	100
Net cash flows provided by (used in) operating activities	15	$ 47	33	$ 39
Effect on shareholders’ equity (decrease) increase	$ (40)		$ (40)		$ (44)