Expenses - Schedule of Expenses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Other Expenses [Abstract]
Litigation	$ 422	$ 173	$ (17)
Insurance	126	80	80
Regulatory fees and assessments	115	74	72
Securities processing	79	68	52
Other	276	356	360
Total Other Expenses	$ 1,018	$ 751	$ 547