Investment Securities (Investments, by type and length in continuous loss position) (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Available-for-sale Securities Estimated Fair Value And Gross Unrealized Losses [Abstract]
Estimated fair value, less than 12 months	$ 4,701	$ 4,273
Gross unrealized losses, less than 12 months	(19)	(269)
Estimated fair value, 12 months or more	686	686
Gross unrealized losses, 12 months or more	(90)	(140)
OTTI Previously Recognized Through OCI On Securities Held, Gross Unrealized Losses	1
US Corporate
Available-for-sale Securities Estimated Fair Value And Gross Unrealized Losses [Abstract]
Estimated fair value, less than 12 months	148	2,966
Gross unrealized losses, less than 12 months	(2)	(218)
Estimated fair value, 12 months or more	387	433
Gross unrealized losses, 12 months or more	(30)	(67)
State and municipal
Available-for-sale Securities Estimated Fair Value And Gross Unrealized Losses [Abstract]
Estimated fair value, less than 12 months	31	494
Gross unrealized losses, less than 12 months	(1)	(20)
Estimated fair value, 12 months or more	157	155
Gross unrealized losses, 12 months or more	(43)	(53)
Mortgage-backed Securities, Residential, Subprime, Financing Receivable [Member]
Available-for-sale Securities Estimated Fair Value And Gross Unrealized Losses [Abstract]
Debt securities, Estimated fair value	52
Mortgage and asset-backed
Available-for-sale Securities Estimated Fair Value And Gross Unrealized Losses [Abstract]
Estimated fair value, less than 12 months	167	719
Gross unrealized losses, less than 12 months	(2)	(20)
Estimated fair value, 12 months or more	112	84
Gross unrealized losses, 12 months or more	(14)	(16)
Corporate - non-U.S.
Available-for-sale Securities Estimated Fair Value And Gross Unrealized Losses [Abstract]
Estimated fair value, less than 12 months	4,088	56
Gross unrealized losses, less than 12 months	(7)	(4)
Estimated fair value, 12 months or more	31	14
Gross unrealized losses, 12 months or more	(3)	(4)
Government - non-U.S.
Available-for-sale Securities Estimated Fair Value And Gross Unrealized Losses [Abstract]
Estimated fair value, less than 12 months	256
Gross unrealized losses, less than 12 months	(1)
Estimated fair value, 12 months or more	0
Gross unrealized losses, 12 months or more	0
Equity Securities
Available-for-sale Securities Estimated Fair Value And Gross Unrealized Losses [Abstract]
Estimated fair value, less than 12 months	11	36
Gross unrealized losses, less than 12 months	(5)	(6)
Estimated fair value, 12 months or more	0	0
Gross unrealized losses, 12 months or more	0	0
GE Capital | Equity Securities
Available-for-sale Securities Estimated Fair Value And Gross Unrealized Losses [Abstract]
Estimated fair value, less than 12 months	11	6
Gross unrealized losses, less than 12 months	$ (5)	$ (2)