Shareholders' Equity Comprehensive Income (Loss) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020		Jun. 30, 2019
Net unrealized gains (losses) on securities arising during the period, before tax		$ 1,532	$ 512	$ 337	[1]	$ 1,169	[1]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax		4	0	(4)	[2]	5	[2]
Impact of DAC, DSIC, unearned revenue, benefit reserves and reinsurance recoverables, before tax		(637)	(259)	(129)		(499)
Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, before Tax		891	253	212		665
Foreign currency translation, before tax		(8)	(15)	(42)		(9)
Other Comprehensive Income (Loss), before Tax		883	238	170		655
Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, Tax		329	60	65	[1]	201	[1]
Reclassification of net (gains) losses on securities included in net income, tax		1	0	(1)		1
Other Comprehensive Income Impact Of DAC DSIC Unearned Revenue Benefit Reserves And Reinsurance Recoverables Tax		(134)	(55)	(27)		(105)
Other Comprehensive Income (Loss), Securities, Available-for-sale, Tax		194	5	39		95
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax		0	(1)	(1)		0
Other Comprehensive Income (Loss), Tax		194	4	38		95
Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, after Tax		1,203	452	272	[1]	968	[1]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax		3	0	(3)		4
Other Comprehensive Income Impact of D A C D S I C Unearned Revenue Benefit Reserves and Reinsurance Recoverables Net of Tax		(503)	(204)	(102)		(394)
Net unrealized gains (losses) on securities		697	248	173		570
Foreign currency translation adjustment		(8)	(14)	(41)		(9)
Other comprehensive income (loss), net of tax		689	234	132		560
Net unrealized gains on securities, before tax [Abstract]
Net unrealized gains (losses) on securities arising during the period, before tax		1,532	512	337	[1]	1,169	[1]
Reclassification of net (gains) losses on securities included in net income, before tax		(4)	0	4	[2]	(5)	[2]
Impact of DAC, DSIC, unearned revenue, benefit reserves and reinsurance recoverables, before tax		(637)	(259)	(129)		(499)
Net unrealized gains (losses) on securities, before tax		891	253	212		665
Net unrealized gains on derivatives, before tax [Abstract]
Reclassification of net (gains) losses on derivatives included in net income, before tax	[3]			0		(1)
Net unrealized gains (losses) on derivatives, before tax				0		(1)
Foreign currency translation, before tax		(8)	(15)	(42)		(9)
Total other comprehensive income (loss), before tax		883	238	170		655
Net unrealized gains (losses) on securities, tax impact [Abstract]
Net unrealized gains (losses) on securities arising during the period, tax		(329)	(60)	(65)	[1]	(201)	[1]
Reclassification of net (gains) losses on securities included in net income, tax		1	0	(1)		1
Impact of DAC, DSIC, unearned revenue, benefit reserves and reinsurance recoverables, tax		134	55	27		105
Net unrealized gains (losses) on securities, tax		(194)	(5)	(39)		(95)
Net unrealized losses on derivatives, tax impact [Abstract]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax				0		0
Net unrealized gains (losses) on derivatives, tax				0		0
Foreign currency translation, tax		0	1	1		0
Total other comprehensive income (loss), tax		(194)	(4)	(38)		(95)
Net unrealized gains (losses) on securities, net of tax [Abstract]
Net unrealized gains (losses) on securities arising during the period, net of tax		1,203	452	272	[1]	968	[1]
Reclassification of net (gains) losses on securities included in net income, net of tax		(3)	0	3		(4)
Impact of DAC, DSIC, unearned revenue, benefit reserves and reinsurance recoverables, net of tax		(503)	(204)	(102)		(394)
Net unrealized gains (losses) on securities, net of tax		697	248	173		570
Net unrealized losses on derivatives, net of tax [Abstract]
Reclassification of net (gains) losses on derivatives included in net income, net of tax				0		(1)
Net unrealized gains (losses) on derivatives, net of tax			0	0		(1)
Foreign currency translation adjustment, net of tax		(8)	(14)	(41)		(9)
Total other comprehensive income (loss), net of tax		$ 689	$ 234	132		560
Interest Expense, Borrowings [Member]
Gain (Loss) Reclassified from Accumulated OCI into Income				$ 0		$ 1

[1] Includes impairments on Available-for-Sale securities related to factors other than credit that were recognized in OCI during the period.

[2] Reclassification amounts are recorded in net investment income.

[3] Includes nil and $1 million pretax gain reclassified to interest and debt expense for the six months ended June 30, 2020 and 2019, respectively.