Condensed Financial Information (Parent Company) (Condensed Balance Sheet) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Feb. 10, 2017	Dec. 31, 2016	Apr. 01, 2016	Dec. 31, 2015
Investments:
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $2,745 and $4,520, respectively)	$ 298,265	$ 308,931
Contractholder-directed equity securities and fair value option securities relating to variable interest entities	12,616	16,745
Short-term investments	3,937	4,870
Other Investments	18,190	17,263
Total investments	436,210	444,067
Cash and Cash Equivalents, at Carrying Value	15,821	12,701		$ 12,651		$ 11,182
Accrued Investment Income Receivable	3,582	3,524
Other Assets	8,408	8,167
Total assets	687,538	719,892
Liabilities
Payables for collateral under securities loaned and other transactions	24,794	25,723
Collateral financing arrangement	1,060	1,121
Junior subordinated debt securities	3,147	3,144
Other Liabilities	22,964	23,982
Total liabilities	634,580	661,022
Stockholders’ Equity
Preferred stock, par value $0.01 per share; $3,405 and $2,100 aggregate liquidation preference, respectively	0	0
Common stock, par value $0.01 per share; 3,000,000,000 shares authorized; 1,171,824,242 and 1,168,710,101 shares issued, respectively; 958,613,542 and 1,043,588,396 shares outstanding, respectively	12	12
Additional paid-in capital	32,474	31,111
Retained earnings	28,926	26,527
Treasury stock, at cost; 213,210,700 and 125,121,705 shares, respectively	(10,393)	(6,401)
Accumulated other comprehensive income (loss)	1,722	7,427		5,366		4,767
Total stockholders’ equity	52,741	58,676
Total liabilities and stockholders' equity	687,538	719,892
Parent Company
Investments:
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $2,745 and $4,520, respectively)	2,726	4,510
Contractholder-directed equity securities and fair value option securities relating to variable interest entities	0	1,357
Short-term investments	16	30
Other Investments	87	127
Total investments	2,829	6,024
Cash and Cash Equivalents, at Carrying Value	376	516		$ 334		$ 421
Accrued Investment Income Receivable	53	24
Investment in subsidiaries	66,567	73,274
Loans to subsidiaries	100	100	$ 750		$ 140
Other Assets	843	1,153
Total assets	70,768	81,091
Liabilities
Payables for collateral under securities loaned and other transactions	9	36
Long-term debt — unaffiliated	11,844	14,599
Long-term debt — affiliated	1,957	2,000
Junior subordinated debt securities	2,456	2,454
Other Liabilities	1,761	3,326
Total liabilities	18,027	22,415
Stockholders’ Equity
Preferred stock, par value $0.01 per share; $3,405 and $2,100 aggregate liquidation preference, respectively	0	0
Common stock, par value $0.01 per share; 3,000,000,000 shares authorized; 1,171,824,242 and 1,168,710,101 shares issued, respectively; 958,613,542 and 1,043,588,396 shares outstanding, respectively	12	12
Additional paid-in capital	32,474	31,111
Retained earnings	28,926	26,527
Treasury stock, at cost; 213,210,700 and 125,121,705 shares, respectively	(10,393)	(6,401)
Accumulated other comprehensive income (loss)	1,722	7,427
Total stockholders’ equity	52,741	58,676
Total liabilities and stockholders' equity	$ 70,768	$ 81,091