Schedule II - Condensed Financial Information, Notes (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	0 Months Ended		12 Months Ended
	Nov. 16, 2011	Nov. 10, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Maturities of debt:
Long-term debt maturities in 2014			$ 0
Long-term debt maturities in 2015			0
Long-term debt maturities in 2016			600
Long-term debt maturities in 2017			250
Long-term debt maturities in 2018			131
Long-term debt maturities after 2018			3,890
Notes To Condensed Statements Details [Abstract]
Interest expense on long-term and short-term debt			270	268	202
Interest paid on long-term and short-term debt			265	248	185
Net proceeds on issuance of long-term debt		2,100	0	0	2,676
Stock Issued During Period, Shares, New Issues	15,200.0
Cost of Common Stock Issued Per Share	$ 42.75
Proceeds From Issuance Of Common Stock Gross	650
Proceeds From Issuance Of Common Stock Net	629
Parent Company [Member]
Notes To Condensed Statements Details [Abstract]
Interest expense on long-term and short-term debt			264	262	195
Interest paid on long-term and short-term debt			259	242	179
Net proceeds on issuance of long-term debt		2,100	0	0	2,661
Average Interest Rate On Intercompany Loan			0.59%	0.71%
Bank letter of credit to provide collateral for subsidiary			3
Payment guarantee on surety bonds obtained by subsidiaries			75
Letter of credit required by insurer of high-deductible self-insurance program			12
Solvency guarantee required by regulators for Insurance subsidiaries			34
Bank letter of credit arranged for subsidiary			23
Guarantee on reserve related to assumed reinsurance business of subsidiary			25
Stock Issued During Period, Shares, New Issues	15.2
Cost of Common Stock Issued Per Share	$ 42.75
Proceeds From Issuance Of Common Stock Gross	650
Proceeds From Issuance Of Common Stock Net	$ 629