Shareholders' Equity And Dividend Restrictions (Change In AOCI Includes Changes In Unrealized Gains And Losses On Investments And Pension Obligations) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accumulated Other Comprehensive Income, Before Tax
Pension obligations OCI	$ (6)	$ (18)	$ 83
Accumulated Other Comprehensive Income, Income Tax
Income taxes on above of other comprehensive (loss) income	(218)	130	202
Accumulated Other Comprehensive Income, Net of Tax
AOCI, balance at the beginning of the period	1,744
Other comprehensive (loss) income before tax	(618)	370	577
AOCI, balance at the end of the period	1,344	1,744
Accumulated Net Unrealized Investment Gain (Loss)
Accumulated Other Comprehensive Income, Before Tax
AOCI, balance at the beginning of the period	2,719	2,335	1,875
OCI before realized gains (losses) recognized in net income	(556)	514	537
Realized gains (losses) recognized in net income	(69)	(130)	(77)
OCI, portion attributable to Parent	(625)	384	460
AOCI, balance at the end of the period	2,094	2,719	2,335
Accumulated Other Comprehensive Income, Income Tax
AOCI, balance at the beginning of the period	942	808	647
OCI before realized gains (losses) recognized in net income	(196)	181	188
Realized gains (losses) recognized in net income	(24)	(47)	(27)
Income taxes on above of other comprehensive (loss) income	(220)	134	161
AOCI, balance at the end of the period	722	942	808
Accumulated Other Comprehensive Income, Net of Tax
AOCI, balance at the beginning of the period	1,777	1,527	1,228
OCI before realized gains (losses) recognized in net income	(360)	333	349
Realized gains (losses) recognized in net income	(45)	(83)	(50)
Other comprehensive (loss) income before tax	(405)	250	299
AOCI, balance at the end of the period	1,372	1,777	1,527
Accumulated Defined Benefit Plans Adjustment
Accumulated Other Comprehensive Income, Before Tax
AOCI, balance at the beginning of the period	(36)	(18)	(101)
OCI before realized gains (losses) recognized in net income	(12)	(21)	83
Realized gains (losses) recognized in net income	6	3	0
OCI, portion attributable to Parent	(6)	(18)	83
AOCI, balance at the end of the period	(42)	(36)	(18)
Accumulated Other Comprehensive Income, Income Tax
AOCI, balance at the beginning of the period	(12)	(6)	(35)
OCI before realized gains (losses) recognized in net income	(5)	(7)	29
Realized gains (losses) recognized in net income	3	1	0
Income taxes on above of other comprehensive (loss) income	(2)	(6)	29
AOCI, balance at the end of the period	(14)	(12)	(6)
Accumulated Other Comprehensive Income, Net of Tax
AOCI, balance at the beginning of the period	(24)	(12)	(66)
OCI before realized gains (losses) recognized in net income	(7)	(14)	54
Realized gains (losses) recognized in net income	3	2	0
Other comprehensive (loss) income before tax	(4)	(12)	54
AOCI, balance at the end of the period	(28)	(24)	(12)
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	(12)	(16)	(50)
OCI before realized gains (losses) recognized in net income	14	7	40
Realized gains (losses) recognized in net income	(1)	(3)	(6)
OCI, portion attributable to Parent	13	4	34
AOCI, balance at the end of the period	1	(12)	(16)
Accumulated Other Comprehensive Income, Income Tax
AOCI, balance at the beginning of the period	(3)	(5)	(17)
OCI before realized gains (losses) recognized in net income	5	3	14
Realized gains (losses) recognized in net income	(1)	(1)	(2)
Income taxes on above of other comprehensive (loss) income	4	2	12
AOCI, balance at the end of the period	1	(3)	(5)
Accumulated Other Comprehensive Income, Net of Tax
AOCI, balance at the beginning of the period	(9)	(11)	(33)
OCI before realized gains (losses) recognized in net income	9	4	26
Realized gains (losses) recognized in net income	0	(2)	(4)
Other comprehensive (loss) income before tax	9	2	22
AOCI, balance at the end of the period	0	(9)	(11)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income, Before Tax
AOCI, balance at the beginning of the period	2,671	2,301	1,724
Investments OCI	(625)	384	460
Pension obligations OCI	(6)	(18)	83
Life deferred acquisition costs, life policy reserves and other OCI	13	4	34
Total OCI	(618)	370	577
AOCI, balance at the end of the period	2,053	2,671	2,301
Accumulated Other Comprehensive Income, Income Tax
AOCI, balance at the beginning of the period	927	797	595
Investments OCI	(220)	134	161
Pension obligations OCI	(2)	(6)	29
Life deferred acquisition costs, life policy reserves and other OCI	4	2	12
Total OCI	(218)	130	202
AOCI, balance at the end of the period	709	927	797
Accumulated Other Comprehensive Income, Net of Tax
AOCI, balance at the beginning of the period	1,744	1,504	1,129
Investments OCI	(405)	250	299
Pension obligations OCI	(4)	(12)	54
Life deferred acquisition costs, life policy reserves and other OCI	9	2	22
Total OCI	(400)	240	375
AOCI, balance at the end of the period	$ 1,344	$ 1,744	$ 1,504