SCHEDULE II - CONDENSED FINANCIAL INFORMATION OF REGISTRANT (Balance Sheets) (Details) - USD ($) $ in Millions		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Assets
Derivative investments		$ 915	$ 927
Other investments		2,296	2,230
Cash and invested cash		1,628	2,722	$ 3,146	$ 3,919
Other assets		6,082	5,006
Total assets		281,763	261,627
Liabilities
Short-term debt		450
Long-term debt		4,894	5,345
Payables for collateral on investments		4,417	4,995
Other liabilities		5,546	5,880
Total liabilities		264,441	247,149
Contingencies and Commitments (See Note 13)
Stockholders' Equity
Preferred stock - 10,000,000 shares authorized
Common stock - 800,000,000 shares authorized		5,693	5,869
Retained earnings		8,399	7,043
Accumulated other comprehensive income (loss)		3,230	1,566
Total stockholders' equity		17,322	14,478	13,617
Total Liabilities and Stockholders' Equity		281,763	261,627
Parent Company [Member]
Assets
Investments in subsidiaries	[1]	20,488	17,576
Derivative investments		187	213
Other investments		77	51
Cash and invested cash		620	611	$ 681	$ 666
Loans and accrued interest to subsidiaries	[1]	2,328	2,542
Other assets		16	27
Total assets		23,716	21,020
Liabilities
Common dividends payable		72	66
Short-term debt		450
Long-term debt		4,894	5,343
Loans from subsidiaries	[1]	476	625
Payables for collateral on investments		65	81
Other liabilities		437	427
Total liabilities		6,394	6,542
Contingencies and Commitments (See Note 13)
Stockholders' Equity
Preferred stock - 10,000,000 shares authorized
Common stock - 800,000,000 shares authorized		5,693	5,869
Retained earnings		8,399	7,043
Accumulated other comprehensive income (loss)		3,230	1,566
Total stockholders' equity		17,322	14,478
Total Liabilities and Stockholders' Equity		$ 23,716	$ 21,020

[1] Eliminated in consolidation.