Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash Flows from Operating Activities
Net Income	$ 917	$ 593
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	140	146
Realized investment (gains) losses	33	(46)
Deferred income taxes (benefits)	9	11
Net changes in assets and liabilities, net of non-operating effects:
Premiums, accounts and notes receivable	(53)	(55)
Reinsurance recoverables	31	41
Deferred policy acquisition costs	(76)	(76)
Other assets	114	(22)
Insurance liabilities	849	868
Accounts payable, accrued expenses and other liabilities	(191)	(186)
Current income taxes	260	291
Distributions from partnership investments	34	45
Other, net	(42)	(31)
Net cash provided by (used in) operating activities	2,025	1,579
Proceeds from investments sold:
Fixed maturities and equity securities	499	414
Investment maturities and repayments:
Fixed maturities and equity securities	297	475
Commercial mortgage loans	28	21
Other sales, maturities and repayments (primarily short-term and other long-term investments)	112	667
Investments purchased or originated:
Fixed maturities and equity securities	(2,259)	(1,240)
Commercial mortgage loans	(68)	(107)
Other (primarily short-term and other long-term investments)	(206)	(256)
Property and equipment purchases, net	(103)	(91)
Net cash provided by (used in) investing activities	(1,700)	(117)
Cash Flows from Financing Activities
Deposits and interest credited to contractholder deposit funds	292	374
Withdrawals and benefit payments from contractholder deposit funds	(306)	(385)
Net change in short-term debt	(3)	(10)
Repayment of long-term debt	(131)	(250)
Repurchase of common stock	(310)	(239)
Issuance of common stock	20	38
Other, net	(92)	(43)
Net cash provided by (used in) financing activities	(530)	(515)
Effect of foreign currency rate changes on cash and cash equivalents	4	23
Net increase / (decrease) in cash and cash equivalents	(201)	970
Cash and cash equivalents, January 1,	2,972	3,185
Cash and cash equivalents, March 31,	2,771	4,155
Supplemental Disclosure of Cash Information:
Income taxes paid, net of refunds	31	(8)
Interest paid	$ 46	$ 70