Consolidated Statements Of Shareholders' Equity (Parenthetical) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Net unrealized appreciation on investments, Change in period, income tax (expense) benefit	$ (83)	$ (93)
Cumulative translation adjustment, Change in period, income tax(expense) benefit	11	(8)
Pension liability adjustment, Change in period, income tax (expense) benefit	(3)	3
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Unrealized Investment Gain (Loss) [Member]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Tax	(87)	(90)
Income tax benefit (expense) from reclassification of unrealized gains	$ 4	$ (3)