Derivative Financial Instruments (Details 6) (Cash Flow Hedges [Member], USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Cash Flow Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Accumulated other comprehensive income (loss), balance at beginning of period	$ 1,514	$ (59)
Gains (losses) deferred in other comprehensive income (loss) on the effective portion of cash flow hedges	(485)	(185)
Amounts reclassified to net derivatives gains (losses)	(12)	4
Amounts reclassified to net investment income	0	1
Amounts reclassified to other expenses	2	2
Amortization of transition adjustment	0	0
Accumulated other comprehensive income (loss), balance at end of period	$ 1,019	$ (237)