Consolidated Statement of Comprehensive Income (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Consolidated Statement of Comprehensive Income (Unaudited)
Net income	$ 864	$ 864	$ 2,685	$ 2,169
Other comprehensive income (loss):
Changes in net unrealized gains on investment securities having no credit losses recognized in the consolidated statement of income	(204)	470	(2,370)	609
Changes in net unrealized gains on investment securities having credit losses recognized in the consolidated statement of income	(2)	41	2	71
Net changes in benefit plan assets and obligations	24	22	78	64
Net changes in unrealized foreign currency translation	112	65	(57)	43
Other comprehensive income (loss) before income taxes	(70)	598	(2,347)	787
Income tax expense (benefit)	(55)	192	(816)	256
Other comprehensive income (loss), net of taxes	(15)	406	(1,531)	531
Comprehensive income	$ 849	$ 1,270	$ 1,154	$ 2,700