Fair Value of Financial Instruments (Carrying and Estimated Fair Values of Financial Instruments) (Details) - USD ($) $ in Millions		Mar. 31, 2019	Dec. 31, 2018
Assets
AFS Fixed Maturity Securities		$ 96,648	$ 92,787
Trading securities		3,231	1,869
Equity securities		153	99
Mortgage loans on real estate		13,925	13,190
Derivative investments		974	1,081
Other investments		2,372	1,962
Carrying Value [Member]
Assets
Trading securities		3,231	1,869
Equity securities		153	99
Mortgage loans on real estate		13,925	13,190
Derivative investments	[1]	974	1,081
Other investments		2,362	1,951
Cash and invested cash		1,320	1,848
Reinsurance related embedded derivatives			188
Indexed annuity ceded embedded derivatives		872	902
Separate account assets		143,369	132,833
Future contract benefits:
Indexed annuity and IUL contracts embedded derivatives		(1,730)	(1,305)
Other contract holder funds:
Remaining guaranteed interest and similar contracts		(1,948)	(542)
Account values of certain investment contracts		(35,737)	(34,500)
Short-term debt		(686)	(288)
Long-term debt		(2,387)	(2,401)
Reinsurance related embedded derivatives		(80)
Other liabilities - derivative liabilities	[1]	(261)	(226)
Other liabilities - GLB ceded embedded derivatives		(489)	(196)
Fair Value [Member]
Assets
Trading securities		3,231	1,869
Equity securities		153	99
Mortgage loans on real estate		13,890	13,020
Derivative investments	[1]	974	1,081
Other investments		2,362	1,951
Cash and invested cash		1,320	1,848
Reinsurance related embedded derivatives			188
Indexed annuity ceded embedded derivatives		872	902
Separate account assets		143,369	132,833
Future contract benefits:
Indexed annuity and IUL contracts embedded derivatives		(1,730)	(1,305)
Other contract holder funds:
Remaining guaranteed interest and similar contracts		(1,948)	(542)
Account values of certain investment contracts		(38,752)	(36,321)
Short-term debt		(686)	(288)
Long-term debt		(2,615)	(2,519)
Reinsurance related embedded derivatives		(80)
Other liabilities - derivative liabilities	[1]	(261)	(226)
Other liabilities - GLB ceded embedded derivatives		(489)	(196)
Fixed Maturity Securities [Member] | Carrying Value [Member]
Assets
AFS Fixed Maturity Securities		96,648	92,787
Fixed Maturity Securities [Member] | Fair Value [Member]
Assets
AFS Fixed Maturity Securities		96,648	92,787
GLB Direct Embedded Derivatives [Member] | Carrying Value [Member]
Assets
Other assets - GLB embedded derivatives		439	123
GLB Direct Embedded Derivatives [Member] | Fair Value [Member]
Assets
Other assets - GLB embedded derivatives		439	123
GLB Ceded Embedded Derivatives [Member] | Carrying Value [Member]
Assets
Other assets - GLB embedded derivatives		50	72
GLB Ceded Embedded Derivatives [Member] | Fair Value [Member]
Assets
Other assets - GLB embedded derivatives		$ 50	$ 72

[1] We have master netting agreements with each of our derivative counterparties, which allow for the netting of our derivative asset and liability positions by counterparty.