Consolidated Balance Sheet Parentheticals (Parentheticals) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Fixed maturities securities at amortized cost	$ 37,253	$ 37,335
Equity securities at cost	191	210
Allowance for uncollectible reinsurance receivables	38	48
Allowance for uncollectible insurance receivables	51	61
Accumulated depreciation on property and equipment	382	364
Due to Related Parties	$ 82	$ 153
Common stock, par value	$ 2.50	$ 2.50
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	273,040,243	273,040,243
Common stock, shares outstanding	270,274,361	269,980,202
Treasury stock, shares	2,765,882	3,060,041