Equity (Reclassifications Out of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)	$ 382	$ 109	$ 535	$ (427)
Net derivative gains (losses)	485	478	394	1,132
Net investment income	3,959	5,410	14,367	15,704
Other expenses	(4,533)	(4,218)	(12,665)	(12,603)
Income (loss) from continuing operations before provision for income tax	2,163	2,952	6,335	6,728
Provision for income tax expense (benefit)	(965)	(858)	(1,855)	(1,916)
Net income (loss)	1,198	2,094	4,480	4,809
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income (loss)	(131)	(193)	(166)	23
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Investment Gains (Losses), Net of Related Offsets
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)	104	167	353	359
Net derivative gains (losses)	(5)	33	(21)	105
Net investment income	3	14	60	99
Income (loss) from continuing operations before provision for income tax	102	214	392	563
Provision for income tax expense (benefit)	(34)	(62)	(134)	(176)
Net income (loss)	68	152	258	387
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains (Losses) on Derivatives
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income (loss) from continuing operations before provision for income tax	(239)	(471)	(490)	(337)
Provision for income tax expense (benefit)	77	158	178	114
Net income (loss)	(162)	(313)	(312)	(223)
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains (Losses) on Derivatives | Interest rate swaps
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net derivative gains (losses)	40	1	52	28
Net investment income	3	3	9	7
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains (Losses) on Derivatives | Interest rate forwards
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net derivative gains (losses)	1	(10)	5	(8)
Net investment income	1	0	3	2
Other expenses	1	1	2	2
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains (Losses) on Derivatives | Foreign currency swaps
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net derivative gains (losses)	(286)	(466)	(563)	(368)
Net investment income	0	(1)	(1)	(2)
Other expenses	0	0	1	1
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gains (Losses) on Derivatives | Credit forwards
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net derivative gains (losses)	1	0	1	0
Net investment income	0	1	1	1
Reclassification out of Accumulated Other Comprehensive Income | Foreign Currency Translation Adjustments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)	0	0	0	(77)
Provision for income tax expense (benefit)	0	0	0	27
Net income (loss)	0	0	0	(50)
Reclassification out of Accumulated Other Comprehensive Income | Defined Benefit Plans Adjustment
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of net actuarial gains (losses)	(58)	(45)	(174)	(136)
Amortization of prior service (costs) credit	1	0	3	0
Income (loss) from continuing operations before provision for income tax	(57)	(45)	(171)	(136)
Provision for income tax expense (benefit)	20	13	59	45
Net income (loss)	$ (37)	$ (32)	$ (112)	$ (91)