Shareholders' Equity And Dividend Restrictions (Change In AOCI Includes Changes In Unrealized Gains And Losses On Investments And Pension Obligations) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income, Before Tax
Pension obligations OCI	$ (18)	$ 83	$ (13)
Accumulated Other Comprehensive Income, Income Tax
Income taxes on above of other comprehensive income	130	202	124
Accumulated Other Comprehensive Income, Net of Tax
AOCI, balance at the beginning of the period	1,504
Other comprehensive income before tax	370	577	352
AOCI, balance at the end of the period	1,744	1,504
Accumulated Net Unrealized Investment Gain (Loss)
Accumulated Other Comprehensive Income, Before Tax
AOCI, balance at the beginning of the period	2,335	1,875	1,489
OCI before realized gains (losses) recognized in net income	514	537	426
Realized gains (losses) recognized in net income	(130)	(77)	(40)
OCI, portion attributable to Parent	384	460	386
AOCI, balance at the end of the period	2,719	2,335	1,875
Accumulated Other Comprehensive Income, Income Tax
AOCI, balance at the beginning of the period	808	647	512
OCI before realized gains (losses) recognized in net income	181	188	149
Realized gains (losses) recognized in net income	(47)	(27)	(14)
Income taxes on above of other comprehensive income	134	161	135
AOCI, balance at the end of the period	942	808	647
Accumulated Other Comprehensive Income, Net of Tax
AOCI, balance at the beginning of the period	1,527	1,228	977
OCI before realized gains (losses) recognized in net income	333	349	277
Realized gains (losses) recognized in net income	(83)	(50)	(26)
Other comprehensive income before tax	250	299	251
AOCI, balance at the end of the period	1,777	1,527	1,228
Accumulated Defined Benefit Plans Adjustment
Accumulated Other Comprehensive Income, Before Tax
AOCI, balance at the beginning of the period	(18)	(101)	(88)
OCI before realized gains (losses) recognized in net income	(21)	83	(13)
Realized gains (losses) recognized in net income	3	0	0
OCI, portion attributable to Parent	(18)	83	(13)
AOCI, balance at the end of the period	(36)	(18)	(101)
Accumulated Other Comprehensive Income, Income Tax
AOCI, balance at the beginning of the period	(6)	(35)	(31)
OCI before realized gains (losses) recognized in net income	(7)	29	(4)
Realized gains (losses) recognized in net income	1	0	0
Income taxes on above of other comprehensive income	(6)	29	(4)
AOCI, balance at the end of the period	(12)	(6)	(35)
Accumulated Other Comprehensive Income, Net of Tax
AOCI, balance at the beginning of the period	(12)	(66)	(57)
OCI before realized gains (losses) recognized in net income	(14)	54	(9)
Realized gains (losses) recognized in net income	2	0	0
Other comprehensive income before tax	(12)	54	(9)
AOCI, balance at the end of the period	(24)	(12)	(66)
Accumulated Net Unrealized Gain (Loss) on Deferred Costs, Reserves And Other
Accumulated Other Comprehensive Income, Before Tax
AOCI, balance at the beginning of the period	(16)	(50)	(29)
OCI before realized gains (losses) recognized in net income	7	40	(19)
Realized gains (losses) recognized in net income	(3)	(6)	(2)
OCI, portion attributable to Parent	4	34	(21)
AOCI, balance at the end of the period	(12)	(16)	(50)
Accumulated Other Comprehensive Income, Income Tax
AOCI, balance at the beginning of the period	(5)	(17)	(10)
OCI before realized gains (losses) recognized in net income	3	14	(7)
Realized gains (losses) recognized in net income	(1)	(2)	0
Income taxes on above of other comprehensive income	2	12	(7)
AOCI, balance at the end of the period	(3)	(5)	(17)
Accumulated Other Comprehensive Income, Net of Tax
AOCI, balance at the beginning of the period	(11)	(33)	(19)
OCI before realized gains (losses) recognized in net income	4	26	(12)
Realized gains (losses) recognized in net income	(2)	(4)	(2)
Other comprehensive income before tax	2	22	(14)
AOCI, balance at the end of the period	(9)	(11)	(33)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income, Before Tax
AOCI, balance at the beginning of the period	2,301	1,724	1,372
Investments OCI	384	460	386
Pension obligations OCI	(18)	83	(13)
Life deferred acquisition costs, life policy reserves and other OCI	4	34	(21)
Total OCI	370	577	352
AOCI, balance at the end of the period	2,671	2,301	1,724
Accumulated Other Comprehensive Income, Income Tax
AOCI, balance at the beginning of the period	797	595	471
Investments OCI	134	161	135
Pension obligations OCI	(6)	29	(4)
Life deferred acquisition costs, life policy reserves and other OCI	2	12	(7)
Total OCI	130	202	124
AOCI, balance at the end of the period	927	797	595
Accumulated Other Comprehensive Income, Net of Tax
AOCI, balance at the beginning of the period	1,504	1,129	901
Investments OCI	250	299	251
Pension obligations OCI	(12)	54	(9)
Life deferred acquisition costs, life policy reserves and other OCI	2	22	(14)
Total OCI	240	375	228
AOCI, balance at the end of the period	$ 1,744	$ 1,504	$ 1,129

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Amount before tax of increase (decrease) in accumulated in equity from transactions and other events and circumstances from non-owner sources. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners (distributions to owners).

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