Consolidated Variable Interest Entities - Effect of Consolidating FG VIE's on Financial Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Variable Interest Entity [Line Items]
Net earned premiums	$ 186	$ 231	$ 512	$ 628
Net investment income	99	94	322	291
Net realized investment gains (losses)	7	(2)	54	(5)
Fair value gains (losses) on FG VIEs	3	(11)	25	11
Loss and LAE	(223)	9	(354)	(183)
Income (loss) before income taxes	313	480	835	746
Less: tax provision (benefit)	105	1	157	62
Net income (loss)	208	479	678	684
Net cash flows provided by (used in) operating activities			354	(189)
Effect on shareholders' equity (decrease) increase	6,878		6,878		$ 6,504
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Net earned premiums	(3)	(4)	(11)	(12)
Net investment income	(2)	(1)	(4)	(8)
Net realized investment gains (losses)	0	0	0	1
Fair value gains (losses) on FG VIEs	3	(11)	25	11
Loss and LAE	1	(1)	5	3
Income (loss) before income taxes	(1)	(17)	15	(5)
Less: tax provision (benefit)	0	(6)	5	(2)
Net income (loss)	(1)	(11)	10	(3)
Net cash flows provided by (used in) operating activities	6	$ 11	16	$ 16
Effect on shareholders' equity (decrease) increase	$ 1		$ 1		$ (9)