Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Securities held to maturity, fixed maturities, fair value	$ 47,937	$ 37,520
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)	670,984,000	669,723,000
Asset derivatives	$ 1,662	$ 676
Liability derivatives	601	371
Investments Other Than Consolidated Variable Interest Entities
Securities available for sale, fixed maturities, amortized cost	66,059	56,903
Securities available for sale, perpetual securities, amortized cost	1,677	1,586
Securities available for sale, equity securities, cost	233	117
Securities held to maturity, fixed maturities, fair value	47,937	37,520
Variable Interest Entity, Consolidated
Securities available for sale, fixed maturities, amortized cost	4,870	3,739
Securities available for sale, perpetual securities, amortized cost	273	255
Securities available for sale, equity securities, cost	1,036	363
Asset derivatives	168	102
Liability derivatives	$ 124	$ 293