Deferred Policy Acquisition Costs, Value of Business Acquired and Other Policy-Related Intangibles (DAC and VOBA) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Deferred Policy Acquisition Costs and Present Value of Future Insurance Profits, Net [Abstract]
Beginning Balance of DAC	$ 14,790	$ 15,570	$ 14,789
Capitalization of DAC	3,013	3,358	3,254
Net investment gains (losses) of DAC and net derivative gains (losses) of DAC	(152)	(117)	(109)
Other expenses of DAC	(2,773)	(2,534)	(2,599)
Total amortization of DAC	(2,925)	(2,651)	(2,708)
Unrealized investment gains (losses) of DAC	(1,312)	(1,461)	511
Effect of foreign currency translation and other of DAC	76	(26)	(276)
Reclassified to assets held-for-sale (1)	(196)	0	0
Ending Balance of DAC	13,446	14,790	15,570
Beginning Balance of VOBA	3,043	3,325	3,630
Net investment gains (losses) of VOBA and net derivative gains (losses) of VOBA	(2)	0	0
Other expenses of VOBA	(233)	(245)	(267)
Total amortization of VOBA	(235)	(245)	(267)
Unrealized investment gains (losses) of VOBA	(4)	(4)	10
Effect of foreign currency translation and other of VOBA	139	(33)	(48)
Ending Balance of VOBA	2,943	3,043	3,325
Balance at December 31,	$ 16,389	$ 17,833	$ 18,895