Consolidated Statement of Comprehensive Income (loss) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Net income (loss)	$ 340	$ 6,232	$ 3,456	$ (545)
Other comprehensive income, net-of-tax:
Net change in available-for-sale debt and marketable equity securities	2,365	(2,158)	2,971	(1,404)
Net change in derivatives	234	(764)	535	(830)
Employee benefit plan adjustments	75	66	1,106	204
Net change in foreign currency translation adjustments	15	(8)	14	25
Other comprehensive income	2,689	(2,864)	4,626	(2,005)
Comprehensive income (loss)	$ 3,029	$ 3,368	$ 8,082	$ (2,550)