Commitments, Contingencies, And Guarantees (Net Realized Gains (Losses) Of Derivative Instrument Activity In Consolidated Statement Of Operations) (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2016	Mar. 31, 2015
Commitments Contingencies And Guarantees [Line Items]
Net realized gains (losses)		$ (284)	$ (56)
Foreign Exchange Future [Member]
Commitments Contingencies And Guarantees [Line Items]
Net realized gains (losses)		(10)	25
All Other Futures Contracts And Options [Member]
Commitments Contingencies And Guarantees [Line Items]
Net realized gains (losses)		(34)	(29)
Convertibles and Bonds with Warrants Attached [Member]
Commitments Contingencies And Guarantees [Line Items]
Net realized gains (losses)	[1]	5	5
Investment And Embedded Derivative Instruments [Member]
Commitments Contingencies And Guarantees [Line Items]
Net realized gains (losses)		(39)	1
Guaranteed Living Benefits [Member]
Commitments Contingencies And Guarantees [Line Items]
Net realized gains (losses)	[2]	(228)	(45)
Single-Stock Future [Member]
Commitments Contingencies And Guarantees [Line Items]
Net realized gains (losses)	[3]	(15)	(11)
Options On Equity Market Indices [Member]
Commitments Contingencies And Guarantees [Line Items]
Net realized gains (losses)	[3]	0	(1)
Guaranteed Living Benefit And Other Derivative Instruments [Member]
Commitments Contingencies And Guarantees [Line Items]
Net realized gains (losses)		(245)	(57)
Other Derivatives [Member]
Commitments Contingencies And Guarantees [Line Items]
Net realized gains (losses)		$ (2)	$ 0

[1] (1) Includes embedded derivatives.

[2] (2) Excludes foreign exchange gains (losses) related to GLB

[3] (3) Related to GMDB and GLB blocks of business.