Investments and Derivative Instruments (Details 3) (USD $) In Millions	6 Months Ended	12 Months Ended
Jun. 30, 2011	Dec. 31, 2010
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	$ 78,437	$ 79,432
Gross Unrealized Gains	3,279	2,896
Gross Unrealized Losses	(2,460)	(3,496)
Fair Value	79,213	78,793
Non-Credit OTTI	(215)	(210)
ABS [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	3,551	3,247
Gross Unrealized Gains	54	38
Gross Unrealized Losses	(308)	(396)
Fair Value	3,297	2,889
Non-Credit OTTI	(11)	(2)
CDOs [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	2,928	3,088
Gross Unrealized Gains		1
Gross Unrealized Losses	(353)	(478)
Fair Value	2,575	2,611
Non-Credit OTTI	(68)	(82)
CMBS [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	7,360	8,297
Gross Unrealized Gains	250	235
Gross Unrealized Losses	(333)	(615)
Fair Value	7,277	7,917
Non-Credit OTTI	(28)	(9)
Corporate [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	39,972	38,496
Gross Unrealized Gains	2,311	2,174
Gross Unrealized Losses	(611)	(747)
Fair Value	41,629	39,884
Non-Credit OTTI	0	7
Foreign govt./govt. agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	1,765	1,627
Gross Unrealized Gains	107	73
Gross Unrealized Losses	(8)	(17)
Fair Value	1,864	1,683
Non-Credit OTTI	0	0
Municipal [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	12,738	12,469
Gross Unrealized Gains	278	150
Gross Unrealized Losses	(235)	(495)
Fair Value	12,781	12,124
Non-Credit OTTI	0	0
RMBS [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	5,487	6,036
Gross Unrealized Gains	144	109
Gross Unrealized Losses	(417)	(462)
Fair Value	5,214	5,683
Non-Credit OTTI	(108)	(124)
U.S. Treasuries [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	3,566	5,159
Gross Unrealized Gains	23	24
Gross Unrealized Losses	(94)	(154)
Fair Value	3,495	5,029
Non-Credit OTTI	0	0
Fixed maturities, AFS [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	77,367	78,419
Gross Unrealized Gains	3,167	2,804
Gross Unrealized Losses	(2,359)	(3,364)
Fair Value	78,132	77,820
Non-Credit OTTI	(215)	(210)
Equity securities, AFS [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost or Amortized Cost	1,070	1,013
Gross Unrealized Gains	112	92
Gross Unrealized Losses	(101)	(132)
Fair Value	1,081	973
Non-Credit OTTI	$ 0	$ 0

Available for Sale Securities Fair Value.

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Available For Sale Securities Non Credit Otti.

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS115-1/124-1
-Paragraph 7
-Footnote 2

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 19

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This item represents the gross unrealized gains for securities which are categorized neither as held-to-maturity nor trading securities. Such gross unrealized gains are the excess of the fair value of the Available-for-sale Securities over their carrying value as of the reporting date. Such gross unrealized gains are included in other comprehensive income in the statement of shareholders' equity, unless the Available-for-sale Security is designated as a hedge. All or a portion of the unrealized holding gain of an available-for-sale security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 22

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 13, 19

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This item represents the gross unrealized losses for securities which are categorized neither as held-to-maturity nor trading securities. Such gross unrealized losses are the excess of the carrying value of the Available-for-sale Securities over their fair value as of the reporting date. Such gross unrealized losses are included in other comprehensive income in the statement of shareholders' equity, unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 16

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 22

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 13, 19

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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