Equity (Reclassifications Out of Accumulated Other Comprehensive Income (Loss)) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other net investment gains (losses)	$ (51)	$ 69	$ 472	$ 119
Net derivative gains (losses)	(546)	(718)	(2,866)	(604)
Net investment income	5,026	5,517	16,385	16,436
Other expenses	(3,977)	(4,245)	(12,140)	(13,341)
Other-than-temporary impairments on fixed maturity securities	(13)	(57)	(77)	(310)
Income (loss) from continuing operations before provision for income tax	976	(1,010)	2,784	1,919
Provision for income tax expense (benefit)	(3)	53	(308)	(710)
Net income (loss)	975	(957)	2,477	1,226
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income (loss)	64		139
Reclassification out of Accumulated Other Comprehensive Income [Member] | Unrealized Investment Gains (Losses), Net of Related Offsets [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other net investment gains (losses)	(96)		365
Net investment income	22		65
Income (loss) from continuing operations before provision for income tax	(95)		374
Provision for income tax expense (benefit)	40		(123)
Net income (loss)	(55)		251
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Other-than-Temporary Impairment [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other-than-temporary impairments on fixed maturity securities	(21)		(56)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Unrealized Gains (Losses) on Derivatives [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income (loss) from continuing operations before provision for income tax	224		(10)
Provision for income tax expense (benefit)	(70)		4
Net income (loss)	154		(6)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Unrealized Gains (Losses) on Derivatives [Member] | Interest Rate Swaps [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net derivative gains (losses)	3		17
Net investment income	2		6
Reclassification out of Accumulated Other Comprehensive Income [Member] | Unrealized Gains (Losses) on Derivatives [Member] | Interest Rate Forwards [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net derivative gains (losses)	2		8
Net investment income	1		2
Other expenses	(1)		(2)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Unrealized Gains (Losses) on Derivatives [Member] | Foreign Currency Swaps [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net derivative gains (losses)	216		(41)
Net investment income	0		(2)
Other expenses	1		1
Reclassification out of Accumulated Other Comprehensive Income [Member] | Unrealized Gains (Losses) on Derivatives [Member] | Credit forwards [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net investment income	0		1
Reclassification out of Accumulated Other Comprehensive Income [Member] | Defined Benefit Plans Adjustment [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of net actuarial gains (losses)	(71)		(212)
Amortization of prior service (costs) credit	17		51
Income (loss) from continuing operations before provision for income tax	(54)		(161)
Provision for income tax expense (benefit)	19		55
Net income (loss)	$ (35)		$ (106)