Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions		Mar. 31, 2018	Dec. 31, 2017
Securities available for sale, fixed maturities, amortized cost	[1]	$ 81,607
Securities held to maturity, fixed maturities, fair value		$ 40,468	$ 38,072
Common stock, par value (in dollars per share)		$ 0.1	$ 0.1
Common stock, shares authorized (in shares)		3,800,000,000	3,800,000,000
Common stock, shares issued (in shares)		1,346,776,000	1,345,762,000
Asset derivatives		$ 797	$ 331
Liability derivatives		353	474
Variable Interest Entity, Consolidated
Securities available for sale, fixed maturities, amortized cost	[2],[3]	4,695	4,538
Asset derivatives	[4]	241	151
Liability derivatives	[4]	86	128
Consolidated Entity Excluding Variable Interest Entities (VIE)
Securities available for sale, fixed maturities, amortized cost	[3]	76,912	70,594
Securities held to maturity, fixed maturities, fair value		40,468	38,072
Loan Receivables and Limited Partnerships | Variable Interest Entity, Consolidated
Other investments held in unit trust, net of reserves, amortized cost		$ 3,994	$ 2,341

[1] Includes perpetual securities, categorized in accordance with their respective economic maturities (the expected maturity date created by the combination of features in the financial instrument)

[2] Includes perpetual securities

[3] Includes perpetual securities, see Notes 1 and 3 of the Notes to the Consolidated Financial Statements

[4] Consists entirely of derivatives