CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities
Net income	$ 2,171	$ 2,850	$ 2,280
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and other non-cash items	371	366	368
Realized capital gains and losses	(30)	(694)	(594)
Loss on extinguishment of debt	0	1	491
(Gain) loss on disposition of operations	(3)	74	688
Interest credited to contractholder funds	761	919	1,278
Changes in:
Policy benefits and other insurance reserves	473	541	(55)
Unearned premiums	638	766	602
Deferred policy acquisition costs	(239)	(220)	(268)
Premium installment receivables, net	(134)	(257)	(205)
Reinsurance recoverables, net	(178)	(1,068)	(729)
Income taxes	(119)	205	573
Other operating assets and liabilities	(95)	(247)	(187)
Net cash provided by operating activities	3,616	3,236	4,242
Proceeds from sales
Fixed income securities	28,693	34,609	21,243
Equity securities	3,754	6,755	3,173
Limited partnership interests	1,101	1,473	1,045
Mortgage loans	6	10	24
Other investments	545	406	151
Investment collections
Fixed income securities	4,432	3,736	5,908
Mortgage loans	538	1,106	1,020
Other investments	293	191	275
Investment purchases
Fixed income securities	(30,758)	(38,759)	(24,087)
Equity securities	(4,960)	(5,443)	(3,677)
Limited partnership interests	(1,343)	(1,398)	(1,312)
Mortgage loans	(687)	(501)	(538)
Other investments	(902)	(972)	(1,084)
Change in short-term investments, net	385	272	(427)
Change in other investments, net	(52)	46	97
Purchases of property and equipment, net	(303)	(288)	(207)
Disposition (acquisition) of operations	0	378	(24)
Net cash provided by investing activities	$ 742	1,621	1,580
Cash flows from financing activities
Proceeds from issuance of long-term debt		0	2,271
Repayments of long-term debt	$ (20)	(1,006)	(2,627)
Proceeds from issuance of preferred stock	0	965	781
Contractholder fund deposits	1,052	1,184	2,174
Contractholder fund withdrawals	(2,327)	(3,446)	(6,556)
Dividends paid on common stock	(483)	(477)	(352)
Dividends paid on preferred stock	(116)	(87)	(6)
Treasury stock purchases	(2,808)	(2,301)	(1,834)
Shares reissued under equity incentive plans, net	130	266	170
Excess tax benefits on share-based payment arrangements	45	41	38
Other	7	(14)	(12)
Net cash used in financing activities	(4,520)	(4,875)	(5,953)
Net decrease in cash	(162)	(18)	(131)
Cash at beginning of year	657	675	806
Cash at end of year	$ 495	$ 657	$ 675