Income Taxes Reconciliation of Provision for Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current Provision:
Federal	$ 4,155	$ 3,883	$ 3,004
State and local	281	271	237
Total current provision	4,436	4,154	3,241
Deferred (benefit) provision	(73)	(117)	1
Total provision for income taxes	$ 4,363	$ 4,037	$ 3,242