Fair Value Measurements - Changes in balances of Level 3 financial liabilities carried at fair value (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Financial liabilities, Beginning Balance		$ (1,557)	$ (1,258)	$ (1,369)	$ (3,861)
Impact of accounting change					2,701
Total realized/unrealized gains (losses) included in Net income		(109)	130	(188)	99
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		0	0	0	0
Purchases and issuances		(53)	(88)	(207)	(183)
Sales and settlements		31	18	76	46
Transfer into Level 3		0	0	0	0
Transfer out of Level 3		0	0	0	0
Financial liabilities, Ending Balance	[1]	(1,688)	(1,198)	(1,688)	(1,198)
Liabilities of MIE
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Financial liabilities, Beginning Balance					(2,701)
Impact of accounting change	[2]				2,701
Total realized/unrealized gains (losses) included in Net income					0
Total realized/unrealized gains (losses) included in other comprehensive income (loss)					0
Purchases and issuances					0
Sales and settlements					0
Transfer into Level 3					0
Transfer out of Level 3					0
Financial liabilities, Ending Balance			0		0
Embedded derivatives
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Financial liabilities, Beginning Balance		(1,557)	(1,258)	(1,369)	(1,160)
Impact of accounting change					0
Total realized/unrealized gains (losses) included in Net income		(109)	130	(188)	99
Total realized/unrealized gains (losses) included in other comprehensive income (loss)		0	0	0	0
Purchases and issuances		(53)	(88)	(207)	(183)
Sales and settlements		31	18	76	46
Transfer into Level 3		0	0	0	0
Transfer out of Level 3		0	0	0	0
Financial liabilities, Ending Balance		$ (1,688)	$ (1,198)	$ (1,688)	$ (1,198)

[1] As discussed previously, these tables exclude the portion of MIE liabilities allocated to Level 3, which are derived from the fair value of the MIE assets.

[2] The impact of implementing new guidance adopted in 2015, as discussed above and in Note A — “Accounting Policies — Managed Investment Entities.”