Accumulated Other Comprehensive Income (Loss) by Component (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), beginning balance	$ 962	$ 126	$ 442	$ 831
Transfer to net assets held for sale
Other comprehensive income (loss), before reclassifications	(136)	(16)	448	(722)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	53	(3)	117	(4)
Other Comprehensive Income (loss), net of tax	(189)	(13)	331	(718)
Accumulated other comprehensive income (loss), ending balance	773	113	773	113
Tax (expense) benefit on amounts reclassified from accumulated other comprehensive income (loss)	(33)	1	(68)	3
Tax (expense) benefit on other comprehensive income (loss)	87	36	(176)	377
Net unrealized gains (losses) on investments with OTTI losses [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), beginning balance	35	26	26	20
Transfer to net assets held for sale			(5)
Other comprehensive income (loss), before reclassifications	1	(4)	15	2
Amounts reclassified from accumulated other comprehensive income (loss), net of tax		(1)		(1)
Other Comprehensive Income (loss), net of tax	1	(3)	15	3
Accumulated other comprehensive income (loss), ending balance	36	23	36	23
Tax (expense) benefit on amounts reclassified from accumulated other comprehensive income (loss)
Tax (expense) benefit on other comprehensive income (loss)	(1)	1	(8)	(2)
Net unrealized gains (losses) on other investments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), beginning balance	1,182	724	692	1,371
Transfer to net assets held for sale			(17)
Other comprehensive income (loss), before reclassifications	(59)	(68)	462	(706)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	24	2	38	11
Other Comprehensive Income (loss), net of tax	(83)	(70)	424	(717)
Accumulated other comprehensive income (loss), ending balance	1,099	654	1,099	654
Tax (expense) benefit on amounts reclassified from accumulated other comprehensive income (loss)	(12)	(2)	(20)	(5)
Tax (expense) benefit on other comprehensive income (loss)	64	38	(209)	387
Net unrealized gains (losses) on discontinued operations [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), beginning balance	37
Transfer to net assets held for sale			22
Other comprehensive income (loss), before reclassifications	(3)		12
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	34		34
Other Comprehensive Income (loss), net of tax	(37)		(22)
Accumulated other comprehensive income (loss), ending balance	0		0
Tax (expense) benefit on amounts reclassified from accumulated other comprehensive income (loss)	(23)		(23)
Tax (expense) benefit on other comprehensive income (loss)	25		15
Pension and postretirement benefits [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), beginning balance	(476)	(711)	(426)	(721)
Transfer to net assets held for sale
Other comprehensive income (loss), before reclassifications	(2)		(2)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	(5)	(4)	45	(14)
Other Comprehensive Income (loss), net of tax	3	4	(47)	14
Accumulated other comprehensive income (loss), ending balance	(473)	(707)	(473)	(707)
Tax (expense) benefit on amounts reclassified from accumulated other comprehensive income (loss)	2	3	(25)	8
Tax (expense) benefit on other comprehensive income (loss)	(1)	(3)	26	(8)
Cumulative foreign currency translation adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss), beginning balance	184	87	150	161
Transfer to net assets held for sale
Other comprehensive income (loss), before reclassifications	(73)	56	(39)	(18)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax
Other Comprehensive Income (loss), net of tax	(73)	56	(39)	(18)
Accumulated other comprehensive income (loss), ending balance	111	143	111	143
Tax (expense) benefit on amounts reclassified from accumulated other comprehensive income (loss)
Tax (expense) benefit on other comprehensive income (loss)