Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets
Allowance for loan losses	$ 5,343	$ 5,756
Employee benefits	2,972	3,378
Accrued expenses and other	7,299	8,637
Non-U.S. operations	5,365	5,106
Tax attribute carryforwards	2,602	570
Gross deferred tax assets	23,581	23,447
Valuation allowance	(735)	(820)
Deferred tax assets, net of valuation allowance	22,846	22,627
Deferred tax liabilities
Depreciation and amortization	3,167	3,073
Mortgage servicing rights, net of hedges	4,968	5,533
Leasing transactions	3,042	2,495
Non-U.S. operations	4,285	4,444
Other, net	4,419	5,392
Gross deferred tax liabilities	19,881	20,937
Net deferred tax assets	2,965	$ 1,690
U.S. federal
Deferred tax liabilities
NOL carryforwards	5,200
State and local
Deferred tax liabilities
NOL carryforwards	509
Non-U.S.
Deferred tax liabilities
NOL carryforwards	288
Non-U.S. tax credit carryforwards	$ 704