Taxation (Components Of Net Deferred Tax Assets) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred Tax Assets, Gross [Abstract]
Loss reserve discount	$ 794	$ 807
Unearned premium reserve	99	93
Foreign tax credits	1,103	1,236
Investments	9	3
Provision for uncollectible balances	81	78
Loss carry-forwards	40	54
Compensation related amounts	185	177
Other	0	7
Total deferred tax assets	2,311	2,455
Deferred Tax Liabilities, Gross [Abstract]
Deferred policy acquisition costs	213	138
VOBA and other intangible assets	321	351
Un-remitted foreign earnings	939	982
Unrealized appreciation on investments	406	210
Depreciation	77	66
Deferred Tax Liabilities, Other	43	28
Total deferred tax liabilities	1,999	1,775
Valuation allowance	17	64
Net deferred tax assets	$ 295	$ 616