Fair Value Measurements (Details - Assets by level) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Fixed maturities:
Total fixed maturities	$ 17,868	$ 16,217
Equity securities	109	100
Short-term investments	151	225
Separate account assets
Total separate account assets	8,362	8,093
Level 3 Financial Assets Carried At Fair Value [Abstract]
Corporate bonds valued at transaction price	88	72
Equity securities valued at transaction price	37	30
Other asset and mortgage-backed securities
Level 3 Fair Value And Significant Unobservable Inputs Developed Directly By Company [Line Items]
Fair Value	558
Other asset and mortgage-backed securities | Maximum [Member]
Level 3 Fair Value And Significant Unobservable Inputs Developed Directly By Company [Line Items]
Liquidity Adjustment to Discount Rates	700
Weighting of Credit Spreads Adjustment to Discount Rates	4,020
Other asset and mortgage-backed securities | Minimum [Member]
Level 3 Fair Value And Significant Unobservable Inputs Developed Directly By Company [Line Items]
Liquidity Adjustment to Discount Rates	60
Weighting of Credit Spreads Adjustment to Discount Rates	70
Other asset and mortgage-backed securities | Weighted Average [Member]
Level 3 Fair Value And Significant Unobservable Inputs Developed Directly By Company [Line Items]
Liquidity Adjustment to Discount Rates	150
Weighting of Credit Spreads Adjustment to Discount Rates	400
Corporate and government bonds
Level 3 Fair Value And Significant Unobservable Inputs Developed Directly By Company [Line Items]
Fair Value	351
Corporate and government bonds | Maximum [Member]
Level 3 Fair Value And Significant Unobservable Inputs Developed Directly By Company [Line Items]
Liquidity Adjustment to Discount Rates	550
Corporate and government bonds | Minimum [Member]
Level 3 Fair Value And Significant Unobservable Inputs Developed Directly By Company [Line Items]
Liquidity Adjustment to Discount Rates	20
Corporate and government bonds | Weighted Average [Member]
Level 3 Fair Value And Significant Unobservable Inputs Developed Directly By Company [Line Items]
Liquidity Adjustment to Discount Rates	230
Fair Value, Inputs, Level 1 [Member]
Fixed maturities:
Federal government and agency	156	217
State and local government	0	0
Foreign government	0	0
Corporate	0	0
Federal agency mortgage-backed	0	0
Other mortgage-backed	0	0
Other asset-backed	0	0
Total fixed maturities	156	217
Equity securities	4	3
Subtotal	160	220
Short-term investments	0	0
GMIB assets	0	0
Other derivative assets	0	0
Total financial assets at fair value, excluding separate accounts	160	220
Financial liabilities at fair value:
GMIB liabilities	0	0
Other derivative liabilities	0	0
Total financial liabilities at fair value	0	0
Separate account assets
Guaranteed separate accounts	255	249
Non-guaranteed separate accounts	1,952	1,804
Total separate account assets	2,207	2,053
Fair Value, Inputs, Level 2 [Member]
Fixed maturities:
Federal government and agency	761	738
State and local government	2,486	2,456
Foreign government	1,314	1,251
Corporate	11,434	10,132
Federal agency mortgage-backed	137	9
Other mortgage-backed	90	79
Other asset-backed	346	363
Total fixed maturities	16,568	15,028
Equity securities	68	67
Subtotal	16,636	15,095
Short-term investments	151	225
GMIB assets	0	0
Other derivative assets	46	45
Total financial assets at fair value, excluding separate accounts	16,833	15,365
Financial liabilities at fair value:
GMIB liabilities	0	0
Other derivative liabilities	32	30
Total financial liabilities at fair value	32	30
Separate account assets
Guaranteed separate accounts	976	1,439
Non-guaranteed separate accounts	4,194	3,851
Total separate account assets	5,170	5,290
Fair Value, Inputs, Level 3 [Member]
Fixed maturities:
Federal government and agency	0	3
State and local government	0	0
Foreign government	25	23
Corporate	557	381
Federal agency mortgage-backed	0	0
Other mortgage-backed	1	1
Other asset-backed	561	564
Total fixed maturities	1,144	972
Equity securities	37	30
Subtotal	1,181	1,002
Short-term investments	0	0
GMIB assets	625	712
Other derivative assets	0	0
Total financial assets at fair value, excluding separate accounts	1,806	1,714
Financial liabilities at fair value:
GMIB liabilities	1,184	1,333
Other derivative liabilities	0	0
Total financial liabilities at fair value	1,184	1,333
Separate account assets
Guaranteed separate accounts	0	0
Non-guaranteed separate accounts	985	750
Total separate account assets	985	750
Level 3 Financial Assets Carried At Fair Value [Abstract]
Other asset and mortgage-backed securities valued using pricing models	562	565
Corporate and government bonds valued using pricing models	$ 494	$ 335