Consolidated Variable Interest Entities - Narrative (Details)		3 Months Ended		6 Months Ended
		Jun. 30, 2016 USD ($) Entity	Jun. 30, 2015 USD ($) Entity	Jun. 30, 2016 USD ($) Entity	Jun. 30, 2015 USD ($) Entity	Dec. 31, 2015 USD ($) Entity	Dec. 31, 2014 Entity
Variable Interest Entity [Line Items]
Net fair value gains and losses on FG VIEs are expected to reverse to zero at maturity of the VIE debt		$ 0		$ 0
Credit Risk Derivatives at Fair Value before Effect of Credit Spread Net 1 [Abstract]
Fair value gains (losses) on FG VIEs		4,000,000	$ 5,000,000	$ 22,000,000	$ (2,000,000)
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Net loss on consolidation					$ 26,000,000
Variable Interest Entity, Number of Entities to be Consolidated | Entity	[1]			0	1
Credit Risk Derivatives at Fair Value before Effect of Credit Spread Net 1 [Abstract]
Fair value gains (losses) on FG VIEs		$ 4,000,000	$ 5,000,000	$ 22,000,000	$ (2,000,000)
Number of VIE that did not require consolidation | Entity		32	37	32	37	34	32
Variable Interest Entity, Not Primary Beneficiary, Aggregated Disclosure [Member]
Credit Risk Derivatives at Fair Value before Effect of Credit Spread Net 1 [Abstract]
Number of VIE that did not require consolidation | Entity		670		670		750
Residential Mortgage Backed Securities and Other Insurance Products [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Credit Risk Derivatives at Fair Value before Effect of Credit Spread Net 1 [Abstract]
Total unpaid principal balance for the VIEs' assets that were over 90 days or more past due		$ 142,000,000		$ 142,000,000		$ 154,000,000
Difference between the aggregate unpaid principal and aggregate fair value of the VIEs' Assets		655,000,000		655,000,000		804,000,000
Change in the instrument specific credit risk of the VIEs' assets		(3,000,000)	$ (50,000,000)	31,000,000	$ (32,000,000)
Unpaid principal for FG VIEs’ liabilities with recourse		885,000,000		885,000,000		1,436,000,000
Unpaid principal for FG VIEs' liabilities with and without recourse		$ 287,000,000		$ 287,000,000		$ 423,000,000

[1] Net loss on deconsolidation was de minimis in Six Months 2016, and net loss on consolidation was $26 million in Six Months 2015, and recorded in “fair value gains (losses) on FG VIEs” in the consolidated statement of operations.