Consolidated Variable Interest Entities - Consolidated FG VIE's By Type of Collateral (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Variable Interest Entity [Line Items]
Financial guaranty variable interest entities' assets with recourse, at fair value	$ 724	$ 1,131
Financial guaranty variable interest entities’ liabilities with recourse, at fair value	832	1,225
Financial guaranty variable interest entities' assets without recourse, at fair value	153	130
Financial guaranty variable interest entities’ liabilities without recourse, at fair value	153	124
Financial guaranty variable interest entities’ assets, at fair value	877	1,261
Financial guaranty variable interest entities’ liabilities, at fair value	985	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	77	84
Financial guaranty variable interest entities’ liabilities with recourse, at fair value	77	84
United States [Member] | First Lien [Member] | RMBS [Member]
Variable Interest Entity [Line Items]
Financial guaranty variable interest entities' assets with recourse, at fair value	482	506
Financial guaranty variable interest entities’ liabilities with recourse, at fair value	523	521
United States [Member] | Second Lien [Member] | RMBS [Member]
Variable Interest Entity [Line Items]
Financial guaranty variable interest entities' assets with recourse, at fair value	165	194
Financial guaranty variable interest entities’ liabilities with recourse, at fair value	$ 232	$ 273