Debt (Maturity Of VIE Notes, By Segment) (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012		Dec. 31, 2011
Schedule Of Maturity Variable Interest Entity Notes By Segment [Line Items]
Variable interest entity notes, financial instruments carried at fair value	$ 3,700
Variable Interest Entity [Member]
Schedule Of Maturity Variable Interest Entity Notes By Segment [Line Items]
2013	341	[1]
2014	430	[1]
2015	427	[1]
2016	761	[1]
2017	465	[1]
Thereafter	4,700	[1]
Total	7,124	[1]	8,697
Variable interest entity notes, financial instruments carried at fair value	3,659		4,754
Structured Finance And International Insurance [Member] | Variable Interest Entity [Member]
Schedule Of Maturity Variable Interest Entity Notes By Segment [Line Items]
2013	341
2014	280
2015	427
2016	425
2017	465
Thereafter	4,551
Total	6,489
Conduits [Member] | Variable Interest Entity [Member]
Schedule Of Maturity Variable Interest Entity Notes By Segment [Line Items]
2014	150
2016	336
Thereafter	149
Total	$ 635

[1] Includes $3.7 billion of VIE notes accounted for at fair value as of December 31, 2012.