Consolidated Statements Of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash Flows from Operating Activities
Net income (loss)	$ 846	$ 536
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Deferred acquisition costs, value of business acquired, deferred sales inducements and deferred front-end loads deferrals and interest, net of amortization	30	(17)
Trading securities purchases, sales and maturities, net	60	113
Change in premiums and fees receivable	65	6
Change in accrued investment income	(20)
Change in future contract benefits and other contract holder funds	(864)	5
Change in reinsurance related assets and liabilities	(92)	(347)
Change in accrued expenses	(96)	(180)
Change in federal income tax accruals	162	(3)
Realized (gain) loss	49	159
Amortization of deferred gain on business sold through reinsurance	(22)	(37)
Other	84	301
Net cash provided by (used in) operating activities	202	536
Cash Flows from Investing Activities
Purchases of available-for-sale securities	(5,513)	(5,727)
Sales of available-for-sale securities	842	2,068
Maturities of available-for-sale securities	2,840	2,579
Purchases of alternative investments	(124)	(129)
Sales and repayments of alternative investments	100	95
Issuance of mortgage loans on real estate	(705)	(956)
Repayment and maturities of mortgage loans on real estate	571	376
Issuance and repayment of policy loans, net	34	38
Net change in collateral on investments and derivatives	(12)	1,474
Other	(37)	(58)
Net cash provided by (used in) investing activities	(2,004)	(240)
Cash Flows from Financing Activities
Proceeds from sales leaseback transaction	45
Deposits of fixed account values, including the fixed portion of variable	5,216	5,015
Withdrawals of fixed account values, including the fixed portion of variable	(2,934)	(2,769)
Transfers to and from separate accounts, net	(770)	(967)
Common stock issued for benefit plans	33	(11)
Repurchase of common stock	(400)	(475)
Dividends paid to common stockholders	(132)	(122)
Net cash provided by (used in) financing activities	1,058	671
Net increase (decrease) in cash and invested cash	(744)	967
Cash and invested cash as of beginning-of-year	2,722	3,146
Cash and invested cash as of end-of-period	$ 1,978	$ 4,113