Goodwill (details) - Other Intangible Assets (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Other intangible assets by major asset class
Intangible assets subject to amortization, gross carrying amount	$ 669		$ 669		$ 661
Intangible assets subject to amortization, accumulated amortization	570		570		527
Intangible assets subject to amortization, net	99		99		134
Amortization expense for other intangible assets	12	11	35	34
Estimated intangible asset amortization expense, remainder of 2014	12		12
Estimated intangible asset amortization expense, 2015	26		26
Estimated intangible asset amortization expense, 2016	10		10
Estimated intangible asset amortization expense, 2017	9		9
Estimated intangible asset amortization expense, 2018	8		8
Customer-related [Member]
Other intangible assets by major asset class
Intangible assets subject to amortization, gross carrying amount	460		460		460
Intangible assets subject to amortization, accumulated amortization	438		438		414
Intangible assets subject to amortization, net	22		22		46
Amortization expense for other intangible assets	8	8	24	23
Fair value adjustment on claims and claim adjustment expense reserves, reinsurance recoverables and other contract-related intangibles [Member]
Other intangible assets by major asset class
Intangible assets subject to amortization, gross carrying amount	209		209		201
Intangible assets subject to amortization, accumulated amortization	132		132		113
Intangible assets subject to amortization, net	77		77		88
Amortization expense for other intangible assets	$ 4	$ 3	$ 11	$ 11