Equity (Reclassifications Out of Accumulated Other Comprehensive Income (Loss)) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment gains (losses)	$ 286	$ (411)
Net derivative gains (losses)	821	343
Net investment income	5,461	5,035
Other expenses	(4,060)	(4,163)
Income (loss) from continuing operations before provision for income tax	3,059	1,826
Provision for income tax expense (benefit)	(896)	(484)
Net income (loss)	2,163	1,339
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income (loss)	(317)	120
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)	139	112
Net derivative gains (losses)	(66)	35
Net investment income	40	26
Income (loss) from continuing operations before provision for income tax	113	173
Provision for income tax expense (benefit)	(35)	(59)
Net income (loss)	78	114
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	(554)	54
Provision for income tax expense (benefit)	196	(19)
Net income (loss)	(358)	35
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)	5	15
Net investment income	3	2
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)	3	0
Net investment income	1	1
Other expenses	1	0
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)	(567)	36
Net investment income	0	(1)
Other expenses	0	1
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)	(44)
Amortization of prior service (costs) credit	1	(1)
Income (loss) from continuing operations before provision for income tax	(57)	(45)
Provision for income tax expense (benefit)	20	16
Net income (loss)	$ (37)	$ (29)