Shareholders' Equity Comprehensive Income (Loss) (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Net unrealized gains on securities, before tax [Abstract]
Net unrealized gains (losses) on securities arising during the period, before tax	[1]	$ 657	$ (552)
Reclassification of net (gains) losses on securities included in net income, before tax	[2]	(5)	(5)
Impact of DAC, DSIC, unearned revenue, benefit reserves and reinsurance recoverables, before tax		(240)	216
Net unrealized gains (losses) on securities, before tax		412	(341)
Net unrealized gains on derivatives, before tax [Abstract]
Reclassification of net (gains) losses on derivatives included in net income, before tax	[3]	(1)	0
Net unrealized gains (losses) on derivatives, before tax		(1)	0
Foreign currency translation, before tax		6	37
Other, before tax		0	0
Total other comprehensive income (loss), before tax		417	(304)
Net unrealized gains (losses) on securities, tax impact [Abstract]
Net unrealized gains (losses) on securities arising during the period, tax	[1]	(141)	123
Reclassification of net (gains) losses on securities included in net income, tax		1	1
Impact of DAC, DSIC, unearned revenue, benefit reserves and reinsurance recoverables, tax		50	(45)
Net unrealized gains (losses) on securities, tax		(90)	79
Net unrealized losses on derivatives, tax impact [Abstract]
Reclassification of net (gains) losses on derivatives included in net income, tax		0	0
Net unrealized gains (losses) on derivatives, tax		0	0
Foreign currency translation, tax		(1)	(8)
Other, tax		0	0
Total other comprehensive income (loss), tax		(91)	71
Net unrealized gains (losses) on securities, net of tax [Abstract]
Net unrealized gains (losses) on securities arising during the period, net of tax	[1]	516	(429)
Reclassification of net (gains) losses on securities included in net income, net of tax		(4)	(4)
Impact of DAC, DSIC, unearned revenue, benefit reserves and reinsurance recoverables, net of tax		(190)	171
Net unrealized gains (losses) on securities, net of tax		322	(262)
Net unrealized losses on derivatives, net of tax [Abstract]
Reclassification of net (gains) losses on derivatives included in net income, net of tax		(1)	0
Net unrealized gains (losses) on derivatives, net of tax		(1)	0
Foreign currency translation adjustment, net of tax		5	29
Other, net of tax		0	0
Total other comprehensive income (loss), net of tax		326	$ (233)
Interest Expense, Borrowings [Member]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net		$ 1

[1] Includes OTTI losses on Available-for-Sale securities related to factors other than credit that were recognized in other comprehensive income (loss) during the period.

[2] amounts are recorded in net investment income.

[3] Includes $1 million pretax gain reclassified to interest and debt expense for the three months ended March 31, 2019