Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Comprehensive Income [Line Items]
Shareholders' net income	$ 380	$ 391	$ 751	$ 804
Net unrealized appreciation (depreciation), fixed maturities	63	89	86	81
Net unrealized appreciation (depreciation), equity securities	1	(2)	2	0
Net unrealized appreciation (depreciation) on securities	64	87	88	81
Net unrealized appreciation (depreciation), derivatives	5	(5)	0	(10)
Net translation of foreign currencies	(43)	40	(8)	88
Postretirement benefits liability adjustment	25	5	36	9
Shareholders' Other comprehensive income (loss)	51	127	116	168
Shareholders' comprehensive income	431	518	867	972
Net income attributable to noncontrolling interest	0	0	0	1
Total Comprehensive income	$ 431	$ 518	$ 867	$ 973