Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Activities
Net (loss) income	$ (3,131)	$ 896	$ 1,682
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Net realized capital (gains) losses	(111)	187	156
Amortization of deferred policy acquisition costs	1,417	1,523	1,502
Additions to deferred policy acquisition costs	(1,383)	(1,390)	(1,390)
Depreciation and amortization	399	398	373
Pension settlement expense	747	0	0
Loss on extinguishment of debt	0	0	21
Loss (gain) on sale of business	3,257	81	(6)
Other operating activities, net	408	178	153
Change in assets and liabilities:
(Increase) decrease in reinsurance recoverables	(935)	272	176
Increase (decrease) in accrued and deferred income taxes	170	(250)	363
Impact of tax reform on accrued and deferred income taxes	877	0	0
Increase in unpaid losses and loss adjustment expenses, reserve for future policy benefits, and unearned premiums	1,648	322	275
Net change in other assets and other liabilities	(1,177)	(151)	(549)
Cash provided by operating activities	2,186	2,066	2,756
Proceeds from the sale/maturity/prepayment of:
Fixed maturities, available-for-sale	31,646	24,486	25,946
Fixed maturities, fair value option	148	238	181
Equity securities, available-for-sale	810	709	1,319
Mortgage loans	734	647	792
Partnerships	274	779	624
Payments for the purchase of:
Fixed maturities, available-for-sale	(30,923)	(21,844)	(27,744)
Fixed maturities, fair value option		(94)	(251)
Equity securities, available-for-sale	(638)	(662)	(1,454)
Mortgage loans	(1,096)	(717)	(870)
Partnerships	(509)	(441)	(620)
Net payments for derivatives	(314)	(247)	(173)
Net additions to property and equipment	(250)	(224)	(307)
Net (payments for) proceeds from short-term investments	(144)	(1,377)	3,071
Other investing activities, net	21	(129)	(29)
Proceeds from businesses sold, net of cash transferred	222	0	0
Amounts paid for business acquired, net of cash acquired	(1,423)	(175)	0
Net cash (used for) provided by investing activities	(1,442)	949	485
Financing Activities
Deposits and other additions to investment and universal life-type contracts	4,602	4,186	4,718
Withdrawals and other deductions from investment and universal life-type contracts	(13,562)	(14,790)	(17,085)
Net transfers from separate accounts related to investment and universal life-type contracts	7,969	9,822	11,046
Repayments at maturity or settlement of consumer notes	(13)	(17)	(33)
Net increase in securities loaned or sold under agreements to repurchase	1,320	188	507
Repayment of debt	(416)	(275)	(773)
Proceeds from the issuance of debt	500	0	0
Net (return) issuance of shares under incentive and stock compensation plans	(10)	9	42
Treasury stock acquired	(1,028)	(1,330)	(1,250)
Dividends paid on common stock	(341)	(334)	(316)
Net cash used for financing activities	(979)	(2,541)	(3,144)
Foreign exchange rate effect on cash	70	(40)	(48)
Net (decrease) increase in cash, including cash classified as assets held for sale	(165)	434	49
Less: Net (decrease) increase in cash classified as assets held for sale	(17)	249	47
Net (decrease) increase in cash, including cash classified as assets held for sale	(148)	185	2
Cash — beginning of period	328	143	141
Cash — end of period	180	328	143
Supplemental Disclosure of Cash Flow Information
Income tax received (paid)	6	(130)	80
Interest paid	$ 322	$ 336	$ 361