Equity (Reclassifications Out of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)	$ (133)	$ (125)	$ 153	$ (536)
Net derivative gains (losses)	(912)	311	(91)	654
Net investment income	4,947	5,259	10,408	10,294
Other expenses	(4,072)	(4,222)	(8,132)	(8,385)
Income (loss) from continuing operations before provision for income tax	1,113	1,950	4,172	3,776
Provision for income tax expense (benefit)	6	(574)	(890)	(1,058)
Net income (loss)	1,119	1,376	3,282	2,715
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income (loss)	282	96	(35)	216
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)	110	80	249	192
Net derivative gains (losses)	50	37	(16)	72
Net investment income	17	59	57	85
Income (loss) from continuing operations before provision for income tax	177	176	290	349
Provision for income tax expense (benefit)	(65)	(55)	(100)	(114)
Net income (loss)	112	121	190	235
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	303	80	(251)	134
Provision for income tax expense (benefit)	(95)	(25)	101	(44)
Net income (loss)	208	55	(150)	90
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)	7	12	12	27
Net investment income	3	2	6	4
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	2	4	2
Net investment income	1	1	2	2
Other expenses	0	1	1	1
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)	290	62	(277)	98
Net investment income	(1)	0	(1)	(1)
Other expenses	1	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 investment income	1	0	1	0
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	(77)	0	(77)
Provision for income tax expense (benefit)	0	27	0	27
Net income (loss)	0	(50)	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)	(47)	(116)	(91)
Amortization of prior service (costs) credit	1	1	2	0
Income (loss) from continuing operations before provision for income tax	(57)	(46)	(114)	(91)
Provision for income tax expense (benefit)	19	16	39	32
Net income (loss)	$ (38)	$ (30)	$ (75)	$ (59)