Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2015		Dec. 31, 2014
Available-for-sale Securities, Amortized Cost Basis	$ 56,830		$ 56,038
Variable Interest Entity, Consolidated, Carrying Amount, Assets	239		246
Other liabilities, variable interest entity liabilities	5	[1]	6	[1]
Common stock, par value	$ 0.01		$ 0.01
Common stock, shares authorized	1,500,000,000		1,500,000,000
Common stock, shares issued	490,923,222		490,923,222
Treasury stock, shares	69,533,810		66,507,690
Collateralized Debt Obligations [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets	0		0
Commercial Loan [Member]
Available-for-sale Securities, Amortized Cost Basis	5,718	[2]	5,574	[2]
Valuation Allowance	(21)		(18)
Fixed Maturities [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets	217		218
Short-term Investments [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets	8		16
Cash [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets	$ 12		$ 9

[1] Included in other liabilities in the Company’s Condensed Consolidated Balance Sheets.

[2] Amortized cost represents carrying value prior to valuation allowances, if any