Schedule V. Valuation and Qualifying Accounts (Schedule of valuation and qualifying accounts) (Details) (Allowance for doubtful accounts, insurance and reinsurance receivables [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Allowance for doubtful accounts, insurance and reinsurance receivables [Member]
Movement in valuation allowances and reserves [Roll Forward]
Balance at beginning of period	$ 155		$ 174		$ 203
Charged to costs and expenses	(40)		(6)		(23)
Charged to other accounts	(1)	[1]	(3)	[1]	5	[1]
Deductions	(5)		(10)		(11)
Balance at end of period	$ 109		$ 155		$ 174

[1] Amount includes effects of foreign currency translation.