Fair Value of Assets and Liabilities (Details 5) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
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	$ (9)	$ (32)	$ 27	$ (84)
Gains (losses) for Level 3 liabilities still held at the balance sheet date, included in earnings	16	(34)	(9)	(26)
Gains (losses) for Level 3 assets and liabilities still held at the balance sheet date, included in earnings	7	(66)	18	(110)
Gains (losses) for Level 3 assets still held at the balance sheet date, included in realized capital gains and losses	(17)	(41)	14	(97)
Gains (losses) for Level 3 assets still held at the balance sheet date, included in investment income	9	9	14	13
Losses (gains) for Level 3 assets still held at the balance sheet date, included in interest credited to contract holder funds	32	(26)	(24)	(63)
Losses (gains) for Level 3 liabilities still held at the balance sheet date, included in life and annuity contract benefits	(17)	(8)	14	37
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	16	(34)	(9)	(26)
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	(1)	(32)	20	(77)
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)	(5)	(5)	(15)
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	1	6	9	10
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	(1)	(27)	(1)	(63)
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	(1)	(11)	(1)	(16)
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	5	18	7
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	(4)		(4)	(10)
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	$ (4)		$ 11	$ 3