Consolidated Statement of Cash Flows (Unaudited) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012
Cash flows from operating activities
Net income	$ 1,821		$ 1,305
Adjustments to reconcile net income to net cash provided by operating activities:
Net realized investment gains	(177)	[1]	(14)	[1]
Depreciation and amortization	435		412
Deferred federal income tax expense	151		125
Amortization of deferred acquisition costs	1,898		1,947
Equity in income from other investments	(175)		(228)
Change in premiums receivable	(403)		(468)
Change in reinsurance recoverables	747		752
Change in deferred acquisition costs	(1,912)		(2,000)
Change in claims and claim adjustment expense reserves	(1,128)		(599)
Change in unearned premium reserves	345		346
Other operating activities	(350)		(313)
Net cash provided by operating activities	1,252		1,265
Cash flows from investing activities
Proceeds from maturities of fixed maturities	3,901		4,167
Proceeds from sales of investments, fixed maturities	572		542
Proceeds from sales of investments, equity securities	50		22
Proceeds from sales of investments, real estate investments			3
Proceeds from sales of investments, other investments	381		386
Purchases of investments, fixed maturities	(4,488)		(5,200)
Purchases of investments, equity securities	(40)		(33)
Purchases of investments, real estate investments	(59)		(58)
Purchases of investments, other investments	(209)		(221)
Net sales of short-term securities	81		367
Securities transactions in course of settlement	60		77
Other investing activities	(157)		(133)
Net cash provided by (used in) investing activities	92		(81)
Cash flows from financing activities
Payment of debt	(500)		(258)
Dividends paid to shareholders	(366)		(341)
Issuance of common stock - employee share options	139		170
Treasury stock acquired - share repurchase authorization	(600)		(707)
Treasury stock acquired - net employee share-based compensation	(59)		(52)
Excess tax benefits from share-based payment arrangements	29		19
Net cash used in financing activities	(1,357)		(1,169)
Effect of exchange rate changes on cash	(9)		1
Net increase (decrease) in cash	(22)		16
Cash at beginning of year	330		214
Cash at end of period	308		230
Supplemental disclosure of cash flow information
Income taxes paid	495		296
Interest paid	$ 184		$ 191

[1] Total other-than-temporary impairment (OTTI) gains (losses) were $(1) million and $11 million for the three months ended June 30, 2013 and 2012, respectively, and $(1) million and $11 million for the six months ended June 30, 2013 and 2012, respectively. Of total OTTI, credit losses of $(2) million and $(4) million for the three months ended June 30, 2013 and 2012, respectively, and $(7) million and $(8) million for the six months ended June 30, 2013 and 2012, respectively, were recognized in net realized investment gains. In addition, unrealized gains from other changes in total OTTI of $1 million and $15 million for the three months ended June 30, 2013 and 2012, respectively, and $6 million and $19 million for the six months ended June 30, 2013 and 2012, respectively, were recognized in other comprehensive income as part of change in net unrealized gains on investment securities having credit losses recognized in the consolidated statement of income.