Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Investments [Abstract]
Fixed maturities, at fair value (amortized cost, $19,942; $18,456)	$ 20,961	$ 19,455
Equity securities, at fair value (cost, $583; $190)	583	190
Commercial Mortgage Loans	1,666	1,864
Policy loans	1,452	1,419
Other long-term investments	1,462	1,404
Short-term investments	691	381
Total investments	26,815	24,713
Cash and cash equivalents	3,185	1,968
Premiums, accounts and notes receivable, net	3,077	3,694
Reinsurance recoverables	6,478	6,813
Deferred policy acquisition costs	1,818	1,659
Property and equipment	1,536	1,534
Deferred tax assets, net	304	379
Goodwill	5,980	6,019
Other assets, including other intangibles	2,227	2,476
Separate account assets	7,940	7,833
Total assets	59,360	57,088
Liabilities:
Contractholder deposit funds	8,458	8,443
Future policy benefits	9,648	9,479
Unpaid claims and claim expenses	4,917	4,574
Global Health Care medical costs payable	2,532	2,355
Unearned premiums	634	629
Total insurance and contractholder liabilities	26,189	25,480
Accounts payable, accrued expenses and other liabilities	6,414	6,493
Short-term debt	276	149
Long-term debt	4,756	5,020
Separate account liabilities	7,940	7,833
Total liabilities	45,575	44,975
Contingencies - Note 21
Redeemable noncontrolling interests	58	69
Shareholders' Equity
Common stock (par value per share, $0.25; shares issued, 296; authorized, 600)	74	74
Additional paid-in capital	2,892	2,859
Accumulated other comprehensive loss	(1,382)	(1,250)
Retained earnings	13,855	12,121
Less: treasury stock, at cost	(1,716)	(1,769)
Total shareholders' equity	13,723	12,035
Noncontrolling interests	4	9
Total equity	13,727	12,044
Total liabilities and equity	$ 59,360	$ 57,088
Shareholders' Equity Per Share	$ 53.42	$ 46.91