Fair Value (Table of reconciliation for assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	$ 1,393	$ 1,751
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	(5)	28
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)		33
Purchases	804	1,225
Sales	(414)	(580)
Settlements	(275)	(494)
Transfers into Level 3	94	59
Transfers out of Level 3	(294)	(629)
Balance, Ending, Assets	1,303	1,393
Unrealized gains (losses) on Level 3 assets and liabilities held at balance sheet date recognized in net income (loss)	(36)	(48)
Fixed maturity securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	1,251	1,507
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	9	11
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	(3)	27
Purchases	801	1,175
Sales	(405)	(539)
Settlements	(251)	(373)
Transfers into Level 3	94	58
Transfers out of Level 3	(293)	(615)
Balance, Ending, Assets	1,203	1,251
Unrealized gains (losses) on Level 3 assets and liabilities held at balance sheet date recognized in net income (loss)	(7)	(21)
Corporate and other bonds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	219	482
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	3	6
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)		4
Purchases	142	231
Sales	(116)	(136)
Settlements	(44)	(88)
Transfers into Level 3	51	45
Transfers out of Level 3	(51)	(325)
Balance, Ending, Assets	204	219
Unrealized gains (losses) on Level 3 assets and liabilities held at balance sheet date recognized in net income (loss)	(2)	(3)
States, municipalities and political subdivisions [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	96	171
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	(2)
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	4
Purchases	122	14
Sales	(79)
Settlements	(61)	(89)
Transfers into Level 3	18
Transfers out of Level 3	(27)
Balance, Ending, Assets	71	96
Unrealized gains (losses) on Level 3 assets and liabilities held at balance sheet date recognized in net income (loss)
Residential mortgage-backed [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	413	452
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	4	(14)
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	(14)	2
Purchases	116	97
Sales	(10)
Settlements	(75)	(40)
Transfers into Level 3	4
Transfers out of Level 3	(107)	(84)
Balance, Ending, Assets	331	413
Unrealized gains (losses) on Level 3 assets and liabilities held at balance sheet date recognized in net income (loss)	(3)	(18)
Commercial Mortgage Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	129	59
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)		8
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	11	14
Purchases	107	165
Sales	(3)	(12)
Settlements	(11)	(28)
Transfers into Level 3	21	13
Transfers out of Level 3	(103)	(90)
Balance, Ending, Assets	151	129
Unrealized gains (losses) on Level 3 assets and liabilities held at balance sheet date recognized in net income (loss)
Other asset-backed [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	368	343
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	5	11
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	(4)	8
Purchases	314	615
Sales	(197)	(365)
Settlements	(35)	(128)
Transfers into Level 3
Transfers out of Level 3	(5)	(116)
Balance, Ending, Assets	446	368
Unrealized gains (losses) on Level 3 assets and liabilities held at balance sheet date recognized in net income (loss)	(2)
Total asset-backed [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	910	854
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	9	5
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	(7)	24
Purchases	537	877
Sales	(210)	(377)
Settlements	(121)	(196)
Transfers into Level 3	25	13
Transfers out of Level 3	(215)	(290)
Balance, Ending, Assets	928	910
Unrealized gains (losses) on Level 3 assets and liabilities held at balance sheet date recognized in net income (loss)	(5)	(18)
Redeemable Preferred Stock [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	26
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	(1)
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)		(1)
Purchases		53
Sales		(26)
Settlements	(25)
Transfers into Level 3
Transfers out of Level 3
Balance, Ending, Assets		26
Unrealized gains (losses) on Level 3 assets and liabilities held at balance sheet date recognized in net income (loss)
Equity securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	34	67
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	(27)	(36)
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)	3	6
Purchases	2	27
Sales		(16)
Settlements
Transfers into Level 3
Transfers out of Level 3	(1)	(14)
Balance, Ending, Assets	11	34
Unrealized gains (losses) on Level 3 assets and liabilities held at balance sheet date recognized in net income (loss)	(27)	(38)
Other invested assets, including derivatives, net
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets		10
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)
Purchases
Sales	(1)
Settlements	1	(10)
Transfers into Level 3
Transfers out of Level 3
Balance, Ending, Assets
Unrealized gains (losses) on Level 3 assets and liabilities held at balance sheet date recognized in net income (loss)
Short-term Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	6	27
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)
Purchases		23
Sales	(6)	(4)
Settlements		(41)
Transfers into Level 3		1
Transfers out of Level 3
Balance, Ending, Assets		6
Unrealized gains (losses) on Level 3 assets and liabilities held at balance sheet date recognized in net income (loss)
Life settlement contracts, included in Other assets [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	100	117
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)	13	53
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)
Purchases
Sales
Settlements	(25)	(70)
Transfers into Level 3
Transfers out of Level 3
Balance, Ending, Assets	88	100
Unrealized gains (losses) on Level 3 assets and liabilities held at balance sheet date recognized in net income (loss)	(2)	11
Separate account business [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, Beginning, Assets	2	23
Net realized investment gains (losses) and net change in unrealized appreciation (depreciation) included in net income (loss)
Net change in unrealized appreciation (depreciation) included in other comprehensive income (loss)
Purchases	1
Sales	(2)	(21)
Settlements
Transfers into Level 3
Transfers out of Level 3
Balance, Ending, Assets	1	2
Unrealized gains (losses) on Level 3 assets and liabilities held at balance sheet date recognized in net income (loss)