Equity (Components of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period	$ 4,771	$ 10,649
OCI before reclassifications	8,917	1,143
Deferred income tax benefit (expense)	(2,631)	(580)
AOCI before reclassifications, net of income tax	11,057	11,212
Amounts reclassified from AOCI	(258)	498
Deferred income tax benefit (expense)	66	(181)
Amounts reclassified from AOCI, net of income tax	(192)	317
Balance, end of period	10,865	11,529
Unrealized Investment Gains (Losses), Net of Related Offsets
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period	10,315	15,159
OCI before reclassifications	7,670	1,626
Deferred income tax benefit (expense)	(2,549)	(501)
AOCI before reclassifications, net of income tax	15,436	16,284
Amounts reclassified from AOCI	17	(113)
Deferred income tax benefit (expense)	(7)	35
Amounts reclassified from AOCI, net of income tax	10	(78)
Balance, end of period	15,446	16,206
Unrealized Gains (Losses) on Derivatives
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period	1,458	1,076
OCI before reclassifications	696	187
Deferred income tax benefit (expense)	(199)	(66)
AOCI before reclassifications, net of income tax	1,955	1,197
Amounts reclassified from AOCI	(323)	554
Deferred income tax benefit (expense)	93	(196)
Amounts reclassified from AOCI, net of income tax	(230)	358
Balance, end of period	1,725	1,555
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period	(4,950)	(3,303)
OCI before reclassifications	551	(670)
Deferred income tax benefit (expense)	117	(13)
AOCI before reclassifications, net of income tax	(4,282)	(3,986)
Amounts reclassified from AOCI	0	0
Deferred income tax benefit (expense)	0	0
Amounts reclassified from AOCI, net of income tax	0	0
Balance, end of period	(4,282)	(3,986)
Defined Benefit Plans Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning of period	(2,052)	(2,283)
OCI before reclassifications	0	0
Deferred income tax benefit (expense)	0	0
AOCI before reclassifications, net of income tax	(2,052)	(2,283)
Amounts reclassified from AOCI	48	57
Deferred income tax benefit (expense)	(20)	(20)
Amounts reclassified from AOCI, net of income tax	28	37
Balance, end of period	$ (2,024)	$ (2,246)