Consolidated Statement of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Consolidated Statement of Comprehensive Income (Unaudited)
Net income	$ 691	$ 833
Other comprehensive income (loss):
Changes in net unrealized gains on investment securities having no credit losses recognized in the consolidated statement of income	714	169
Changes in net unrealized gains on investment securities having credit losses recognized in the consolidated statement of income	5	(5)
Net changes in benefit plan assets and obligations	16	24
Net changes in unrealized foreign currency translation	103	(274)
Other comprehensive income (loss) before income taxes	838	(86)
Income tax expense	267	25
Other comprehensive income (loss), net of taxes	571	(111)
Comprehensive income	$ 1,262	$ 722