Investments (Details 3) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013 Holdings	Dec. 31, 2012 Holdings
Indemnity
Fair value
Less than 12 months	$ 129	$ 92
12 months or longer	26	6
Total	155	98
Unrealized losses
Less than 12 months	3	0
12 months or longer	0	1
Total	3	1
No. of holdings	38	19
Indemnity | Investment grade
Fair value
Less than 12 months	112	55
12 months or longer	10	3
Total	122	58
Unrealized losses
Less than 12 months	1	0
12 months or longer	0	0
Total	1	0
No. of holdings	32	12
Indemnity | Non-investment grade
Fair value
Less than 12 months	0	4
12 months or longer	0	0
Total	0	4
Unrealized losses
Less than 12 months	0	0
12 months or longer	0	0
Total	0	0
No. of holdings	0	1
Indemnity | Fixed maturities
Fair value
Less than 12 months	112	59
12 months or longer	10	3
Total	122	62
Unrealized losses
Less than 12 months	1	0
12 months or longer	0	0
Total	1	0
No. of holdings	32	13
Indemnity | States & political subdivisions
Fair value
Less than 12 months	58
12 months or longer	0
Total	58
Unrealized losses
Less than 12 months	1
12 months or longer	0
Total	1
No. of holdings	21
Indemnity | Corporate debt securities
Fair value
Less than 12 months	54	59
12 months or longer	10	0
Total	64	59
Unrealized losses
Less than 12 months	0	0
12 months or longer	0	0
Total	0	0
No. of holdings	11	12
Indemnity | Commercial mortgage-backed securities
Fair value
Less than 12 months		0
12 months or longer		3
Total		3
Unrealized losses
Less than 12 months		0
12 months or longer		0
Total		0
No. of holdings		1
Indemnity | Nonredeemable preferred stock
Fair value
Less than 12 months	5	7
12 months or longer	3	3
Total	8	10
Unrealized losses
Less than 12 months	1	0
12 months or longer	0	1
Total	1	1
No. of holdings	4	4
Indemnity | Common stock
Fair value
Less than 12 months	12	26
12 months or longer	13	0
Total	25	26
Unrealized losses
Less than 12 months	1	0
12 months or longer	0	0
Total	1	0
No. of holdings	2	2
Exchange
Fair value
Less than 12 months	2,050	694
12 months or longer	176	48
Total	2,226	742
Unrealized losses
Less than 12 months	74	7
12 months or longer	5	1
Total	79	8
No. of holdings	388	77
Exchange | Investment grade
Fair value
Less than 12 months	1,707	296
12 months or longer	62	24
Total	1,769	320
Unrealized losses
Less than 12 months	57	4
12 months or longer	4	0
Total	61	4
No. of holdings	344	53
Exchange | Non-investment grade
Fair value
Less than 12 months	64	20
12 months or longer	0	6
Total	64	26
Unrealized losses
Less than 12 months	4	1
12 months or longer	0	0
Total	4	1
No. of holdings	14	8
Exchange | Fixed maturities
Fair value
Less than 12 months	1,771	316
12 months or longer	62	30
Total	1,833	346
Unrealized losses
Less than 12 months	61	5
12 months or longer	4	0
Total	65	5
No. of holdings	358	61
Exchange | U.S. government & agencies
Fair value
Less than 12 months	1	80
12 months or longer	0	0
Total	1	80
Unrealized losses
Less than 12 months	0	1
12 months or longer	0	0
Total	0	1
No. of holdings	2	7
Exchange | States & political subdivisions
Fair value
Less than 12 months	408	23
12 months or longer	18	0
Total	426	23
Unrealized losses
Less than 12 months	13	0
12 months or longer	2	0
Total	15	0
No. of holdings	100	11
Exchange | Foreign government securities
Fair value
Less than 12 months	5
12 months or longer	0
Total	5
Unrealized losses
Less than 12 months	0
12 months or longer	0
Total	0
No. of holdings	1
Exchange | Corporate debt securities
Fair value
Less than 12 months	1,251	152
12 months or longer	36	9
Total	1,287	161
Unrealized losses
Less than 12 months	43	3
12 months or longer	2	0
Total	45	3
No. of holdings	237	31
Exchange | Residential mortgage-backed securities
Fair value
Less than 12 months	71	56
12 months or longer	8	0
Total	79	56
Unrealized losses
Less than 12 months	4	1
12 months or longer	0	0
Total	4	1
No. of holdings	12	9
Exchange | Commercial mortgage-backed securities
Fair value
Less than 12 months	5
12 months or longer	0
Total	5
Unrealized losses
Less than 12 months	0
12 months or longer	0
Total	0
No. of holdings	1
Exchange | Collateralized debt obligations
Fair value
Less than 12 months		0
12 months or longer		21
Total		21
Unrealized losses
Less than 12 months		0
12 months or longer		0
Total		0
No. of holdings		1
Exchange | Other debt securities
Fair value
Less than 12 months	30	5
12 months or longer	0	0
Total	30	5
Unrealized losses
Less than 12 months	1	0
12 months or longer	0	0
Total	1	0
No. of holdings	5	2
Exchange | Nonredeemable preferred stock
Fair value
Less than 12 months	182	64
12 months or longer	13	18
Total	195	82
Unrealized losses
Less than 12 months	10	0
12 months or longer	1	1
Total	11	1
No. of holdings	27	13
Exchange | Common stock
Fair value
Less than 12 months	97	314
12 months or longer	101	0
Total	198	314
Unrealized losses
Less than 12 months	3	2
12 months or longer	0	0
Total	$ 3	$ 2
No. of holdings	3	3