Condensed Financial Information (Parent Company) (Condensed Balance Sheet) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Investments:
Estimated Fair Value of Fixed Maturity Securities AFS	$ 354,809	$ 327,820
Short-term investments, principally at estimated fair value	3,904	3,850
Other invested assets, at estimated fair value	20,593	19,015
Total investments	508,519	473,795
Cash and cash equivalents	19,795	16,598
Accrued investment income	3,388	3,523
Other assets	11,685	10,518
Total assets	795,146	740,463
Liabilities
Payables for collateral under derivatives transactions	29,475	26,745
Junior subordinated debt securities	3,153	3,150
Other liabilities	23,614	24,179
Total liabilities	720,329	674,081
Stockholders’ Equity
Preferred stock, par value $0.01 per share; $4,405 and $3,405, respectively, aggregate liquidation preference	0	0
Common stock, par value $0.01 per share; 3,000,000,000 shares authorized; 1,181,614,288 and 1,177,680,299 shares issued, respectively; 892,910,600 and 915,338,098 shares outstanding, respectively	12	12
Additional paid-in capital	33,812	32,680
Retained earnings	36,491	33,078
Treasury stock, at cost; 288,703,688 and 262,342,201 shares, respectively	(13,829)	(12,678)
Accumulated other comprehensive income (loss)	18,072	13,052	$ 1,722	$ 7,427
Total stockholders’ equity	74,558	66,144
Total liabilities and stockholders' equity	$ 795,146	$ 740,463
Common stock, Shares Authorized	3,000,000,000	3,000,000,000
Parent Company
Investments:
Estimated Fair Value of Fixed Maturity Securities AFS	$ 3,443	$ 3,073
Short-term investments, principally at estimated fair value	156	2
Other invested assets, at estimated fair value	187	120
Total investments	3,786	3,195
Cash and cash equivalents	441	377	$ 376	$ 516
Accrued investment income	11	12
Investment in subsidiaries	88,684	79,571
Loans to subsidiaries	0	100
Other assets	966	747
Total assets	93,888	84,002
Liabilities
Payables for collateral under derivatives transactions	65	16
Long-term debt — unaffiliated	13,463	12,379
Long-term debt — affiliated	2,073	1,976
Junior subordinated debt securities	2,461	2,458
Other liabilities	1,268	1,029
Total liabilities	19,330	17,858
Stockholders’ Equity
Preferred stock, par value $0.01 per share; $4,405 and $3,405, respectively, aggregate liquidation preference	0	0
Common stock, par value $0.01 per share; 3,000,000,000 shares authorized; 1,181,614,288 and 1,177,680,299 shares issued, respectively; 892,910,600 and 915,338,098 shares outstanding, respectively	12	12
Additional paid-in capital	33,812	32,680
Retained earnings	36,491	33,078
Treasury stock, at cost; 288,703,688 and 262,342,201 shares, respectively	(13,829)	(12,678)
Accumulated other comprehensive income (loss)	18,072	13,052
Total stockholders’ equity	74,558	66,144
Total liabilities and stockholders' equity	$ 93,888	$ 84,002
Common stock, Shares Authorized	3,000,000,000	3,000,000,000