Fair Value of Assets and Liabilities (Details 4) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets still held at the balance sheet date, included in earnings	$ (32)	$ (218)	$ (84)	$ (432)
Gains (losses) for Level 3 liabilities still held at the balance sheet date, included in earnings	(34)	(30)	(26)	(12)
Gains (losses) for Level 3 assets and liabilities still held at the balance sheet date, included in earnings	(66)	(248)	(110)	(444)
Gains (losses) for Level 3 assets still held at the balance sheet date, included in realized capital gains and losses	(41)	(233)	(97)	(461)
Gains (losses) for Level 3 assets still held at the balance sheet date, included in investment income	9	20	13	34
Losses (gains) for Level 3 assets still held at the balance sheet date, included in interest credited to contractholder funds	(26)	(5)	(63)	(5)
Losses (gains) for Level 3 liabilities still held at the balance sheet date, included in life and annuity contract benefits	(8)	(30)	37	(12)
Fixed income securities
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets still held at the balance sheet date, included in earnings	(32)	(156)	(77)	(285)
Municipal
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets still held at the balance sheet date, included in earnings	(5)	(31)	(15)	(43)
Corporate
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets still held at the balance sheet date, included in earnings	6	(14)	10	(50)
Residential mortgage-backed securities ("RMBS")
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets still held at the balance sheet date, included in earnings	(27)	(106)	(63)	(164)
Commercial mortgage-backed securities ("CMBS")
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets still held at the balance sheet date, included in earnings	(11)	(19)	(16)	(43)
Asset-backed securities ("ABS")
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets still held at the balance sheet date, included in earnings	5	14	7	15
Equity securities
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets still held at the balance sheet date, included in earnings		(7)	(10)	(6)
Free-standing derivatives, net
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 assets still held at the balance sheet date, included in earnings		(55)	3	(141)
Derivatives embedded in life and annuity contracts
Gains (losses) included in net income for Level 3 assets and liabilities:
Gains (losses) for Level 3 liabilities still held at the balance sheet date, included in earnings	$ (34)	$ (30)	$ (26)	$ (12)

This item represents the amount of the total change in unrealized (holding) gains or losses for the period which are included in the statement of income (or changes in net assets). Such unrealized (holding) gains or losses relate to those assets and liabilities still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

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This item represents the amount of the total change in unrealized (holding) gains or losses for the period which are included in the statement of income (or changes in net assets). Such unrealized (holding) gains or losses relate to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

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This item represents the amount of the total change in unrealized (holding) gains or losses for the period which are included in the statement of income (or changes in net assets). Such unrealized (holding) gains or losses relate to those liabilities still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

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This item represents the amount of the total change in unrealized (holding) gains or losses for the period which are related to life and annuity contracts benefits. Such unrealized (holding) gains or losses relate to those liabilities still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph d

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