Consolidated Statement of Cash Flows (Unaudited) - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016
Cash flows from operating activities
Net income		$ 1,212	$ 1,355
Adjustments to reconcile net income to net cash provided by operating activities:
Net realized investment gains	[1]	(85)	(10)
Depreciation and amortization		409	413
Deferred federal income tax expense		106	75
Amortization of deferred acquisition costs		2,035	1,960
Equity in income from other investments		(210)	(44)
Premiums receivable		(609)	(567)
Reinsurance recoverables		157	316
Deferred acquisition costs		(2,157)	(2,062)
Claims and claim adjustment expense reserves		498	(387)
Unearned premium reserves		689	531
Other operating activities		(460)	(287)
Net cash provided by operating activities		1,585	1,293
Cash flows from investing activities
Proceeds from maturities of fixed maturities		4,300	3,773
Proceeds from sales of investments:
Fixed maturities		563	739
Equity securities		200	38
Real estate investments		20	69
Other investments		403	343
Purchases of investments:
Fixed maturities		(5,673)	(5,705)
Equity securities		(166)	(26)
Real estate investments		(26)	(20)
Other investments		(259)	(290)
Net (purchases) sales of short-term securities		(424)	681
Securities transactions in course of settlement		170	461
Other investing activities		(129)	(154)
Net cash used in investing activities		(1,021)	(91)
Cash flows from financing activities
Treasury stock acquired - share repurchase authorization		(700)	(1,100)
Treasury stock acquired - net employee share-based compensation		(61)	(59)
Dividends paid to shareholders		(389)	(375)
Payment of debt		(207)	(400)
Issuance of debt		689	491
Issuance of common stock - employee share options		118	129
Net cash used in financing activities		(550)	(1,314)
Effect of exchange rate changes on cash		7	(3)
Net increase (decrease) in cash		21	(115)
Cash at beginning of year		307	380
Cash at end of period		328	265
Supplemental disclosure of cash flow information
Income taxes paid		323	467
Interest paid		$ 178	$ 180

[1] Total other-than-temporary impairment (OTTI) losses were $(5) million and $(4) million for the three months ended June 30, 2017 and 2016, respectively, and $(6) million and $(32) million for the six months ended June 30, 2017 and 2016, respectively. Of total OTTI, credit losses of $(5) million and $(4) million for the three months ended June 30, 2017 and 2016, respectively, and $(7) million and $(22) million for the six months ended June 30, 2017 and 2016, respectively, were recognized in net realized investment gains. In addition, unrealized gains (losses) from other changes in total OTTI of $0 million for each of the three months ended June 30, 2017 and 2016, and $1 million and $(10) million for the six months ended June 30, 2017 and 2016, respectively, were recognized in other comprehensive income as part of changes in net unrealized gains on investment securities having credit losses recognized in the consolidated statement of income.