Consolidated Statements Of Shareholders' Equity (Parenthetical) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Net unrealized appreciation on investments, Change in period, income tax (expense) benefit	$ (161)	$ 353
Cumulative translation adjustment, Change in period, income tax(expense) benefit	7	27
Pension liability adjustment, Change in period, income tax (expense) benefit	3	(6)
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Unrealized appreciation on investments, Change in period before reclassification to AOCI, income tax (expense) benefit	(18)	81
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Unrealized Investment Gain (Loss) [Member]
Unrealized appreciation on investments, Change in period before reclassification to AOCI, income tax (expense) benefit	7	16
Income tax expense from reclassification of unrealized gains	$ (168)	$ 337