Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash Flows from Operating Activities
Net Income	$ 2,094	$ 1,478	$ 1,624
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	588	597	560
Realized investment (gains) losses	(154)	(213)	(44)
Deferred income taxes	(22)	197	134
Net changes in assets and liabilities, net of non-operating effects:
Premiums, accounts and notes receivable	(780)	(110)	(71)
Reinsurance recoverables	22	369	62
Deferred policy acquisition costs	(176)	(227)	(159)
Other assets	(265)	405	31
Insurance liabilities	457	1,040	245
Accounts payable, accrued expenses and other liabilities	202	(483)	(132)
Current income taxes	111	(56)	29
Cash used to exit Run-off Reinsurance business	0	(2,196)	0
Proceeds from sales of mortgage loans held for sale	0	0	61
Other, net	(83)	(82)	10
Net cash provided by / (used in) operating activities	1,994	719	2,350
Proceeds from investments sold:
Fixed maturities and equity securities	1,769	1,775	591
Investment maturities and repayments:
Fixed maturities and equity securities	1,640	1,621	1,507
Commercial mortgage loans	453	653	722
Other sales, maturities and repayments (primarily short-term and other long-term investments)	2,706	1,661	831
Investments purchased or originated:
Fixed maturities and equity securities	(5,424)	(3,062)	(2,334)
Commercial mortgage loans	(287)	(58)	(364)
Other (primarily short-term and other long-term investments)	(2,115)	(1,930)	(821)
Property and equipment purchases	(473)	(527)	(408)
Acquisitions, net of cash acquired	0	(76)	(3,581)
Other, net	(24)	(42)	0
Net cash provided by/ (used in) investing activities	(1,755)	15	(3,857)
Cash Flows from Financing Activities
Deposits and interest credited to contractholder deposit funds	1,482	1,399	1,337
Withdrawals and benefit payments from contractholder deposit funds	(1,456)	(1,358)	(1,264)
Net change in short-term debt	(112)	(101)	98
Repayment of long-term debt	0	(15)	(326)
Repurchase of common stock	(1,612)	(1,003)	(208)
Issuance of common stock	110	150	121
Common dividends paid	(11)	(11)	(11)
Other, net	17	9	25
Net cash (used in) / provided by financing activities	(1,582)	(930)	(228)
Effect of foreign currency rate changes on cash and cash equivalents	(32)	13	23
Net increase (decrease) in cash and cash equivalents	(1,375)	(183)	(1,712)
Cash and cash equivalents, beginning of year	2,795	2,978	4,690
Cash and cash equivalents, end of year	1,420	2,795	2,978
Supplemental Disclosure of Cash Information:
Income taxes paid, net of refunds	1,085	519	655
Interest paid	$ 259	$ 265	$ 248