Condensed Financial Information (Parent Company) (Condensed Balance Sheet) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Investments:
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $3,062 and $2,745, respectively)	$ 327,820	$ 298,265
Contractholder-directed equity securities and fair value option securities relating to variable interest entities	13,102	12,616
Short-term investments	3,850	3,937
Other Investments	19,015	18,190
Total investments	473,795	436,210
Cash and Cash Equivalents, at Carrying Value	16,598	15,821
Accrued Investment Income Receivable	3,523	3,582
Other Assets	10,518	8,408
Total assets	740,463	687,538
Liabilities
Payables for collateral under securities loaned and other transactions	26,745	24,794
Collateral financing arrangement	993	1,060
Junior subordinated debt securities	3,150	3,147
Other Liabilities	24,179	22,964
Total liabilities	674,081	634,580
Stockholders’ Equity
Preferred stock, par value $0.01 per share; $3,405 aggregate liquidation preference	0	0
Common stock, par value $0.01 per share; 3,000,000,000 shares authorized; 1,177,680,299 and 1,171,824,242 shares issued, respectively; 915,338,098 and 958,613,542 shares outstanding, respectively	12	12
Additional paid-in capital	32,680	32,474
Retained earnings	33,078	28,926
Treasury stock, at cost; 262,342,201 and 213,210,700 shares, respectively	(12,678)	(10,393)
Accumulated other comprehensive income (loss)	13,052	1,722	$ 7,427	$ 5,366
Total stockholders’ equity	66,144	52,741
Total liabilities and stockholders' equity	740,463	687,538
Parent Company
Investments:
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $3,062 and $2,745, respectively)	3,073	2,726
Short-term investments	2	16
Other Investments	120	87
Total investments	3,195	2,829
Cash and Cash Equivalents, at Carrying Value	377	376	$ 516	$ 334
Accrued Investment Income Receivable	12	53
Investment in subsidiaries	79,571	66,567
Loans to subsidiaries	100	100
Other Assets	747	843
Total assets	84,002	70,768
Liabilities
Payables for collateral under securities loaned and other transactions	16	9
Long-term debt — unaffiliated	12,379	11,844
Long-term debt — affiliated	1,976	1,957
Junior subordinated debt securities	2,458	2,456
Other Liabilities	1,029	1,761
Total liabilities	17,858	18,027
Stockholders’ Equity
Preferred stock, par value $0.01 per share; $3,405 aggregate liquidation preference	0	0
Common stock, par value $0.01 per share; 3,000,000,000 shares authorized; 1,177,680,299 and 1,171,824,242 shares issued, respectively; 915,338,098 and 958,613,542 shares outstanding, respectively	12	12
Additional paid-in capital	32,680	32,474
Retained earnings	33,078	28,926
Treasury stock, at cost; 262,342,201 and 213,210,700 shares, respectively	(12,678)	(10,393)
Accumulated other comprehensive income (loss)	13,052	1,722
Total stockholders’ equity	66,144	52,741
Total liabilities and stockholders' equity	$ 84,002	$ 70,768