Summary of Significant Accounting Policies - Schedule of Amounts Associated with Processing Services Revenue (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accounting Policies [Abstract]
Interchange fees and assessments	$ 21,711	$ 20,406	$ 19,368
PIN debit fees	$ 2,991	$ 2,965	$ 2,915