Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions		Sep. 30, 2017	Dec. 31, 2016
Securities held to maturity, fixed maturities, fair value		$ 38,599	$ 40,021
Common stock, par value (in dollars per share)		$ 0.1	$ 0.1
Common stock, shares authorized (in shares)		1,900,000,000	1,900,000,000
Common stock, shares issued (in shares)		672,669,000	671,249,000
Asset derivatives		$ 479	$ 1,207
Liability derivatives		974	1,998
Variable Interest Entity, Consolidated
Securities available for sale, fixed maturities, amortized cost		4,274	4,168
Securities available for sale, perpetual securities, amortized cost		239	237
Securities available for sale, equity securities, cost		595	972
Asset derivatives	[1]	148	127
Liability derivatives	[1]	132	146
Investments Other Than Consolidated Variable Interest Entities
Securities available for sale, fixed maturities, amortized cost		67,970	62,195
Securities available for sale, perpetual securities, amortized cost		1,310	1,269
Securities available for sale, equity securities, cost		216	231
Securities held to maturity, fixed maturities, fair value		38,599	40,021
Loan Receivables and Limited Partnerships | Variable Interest Entity, Consolidated
Other investments held in unit trust, net of reserves, amortized cost		$ 1,500	$ 819

[1] Consists entirely of derivatives