Consolidated Variable Interest Entities - Consolidated FG VIE's By Type of Collateral (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Variable Interest Entity [Line Items]
Financial guaranty variable interest entities' assets with recourse, at fair value	$ 725	$ 1,131
Financial guaranty variable interest entities’ liabilities with recourse, at fair value	807	1,225
Financial guaranty variable interest entities' assets without recourse, at fair value	151	130
Financial guaranty variable interest entities’ liabilities without recourse, at fair value	151	124
Financial guaranty variable interest entities’ assets, at fair value	876	1,261
Financial guaranty variable interest entities’ liabilities, at fair value	958	1,349
Life Insurance [Member]
Variable Interest Entity [Line Items]
Financial guaranty variable interest entities' assets with recourse, at fair value	0	347
Financial guaranty variable interest entities’ liabilities with recourse, at fair value	0	347
Manufactured Housing Loans [Member]
Variable Interest Entity [Line Items]
Financial guaranty variable interest entities' assets with recourse, at fair value	74	84
Financial guaranty variable interest entities’ liabilities with recourse, at fair value	75	84
United States [Member] | First Lien [Member] | Residential Mortgage-Backed Securities (RMBS) [Member]
Variable Interest Entity [Line Items]
Financial guaranty variable interest entities' assets with recourse, at fair value	473	506
Financial guaranty variable interest entities’ liabilities with recourse, at fair value	509	521
United States [Member] | Second Lien [Member] | Residential Mortgage-Backed Securities (RMBS) [Member]
Variable Interest Entity [Line Items]
Financial guaranty variable interest entities' assets with recourse, at fair value	178	194
Financial guaranty variable interest entities’ liabilities with recourse, at fair value	$ 223	$ 273