Expenses - Schedule of Expenses (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Other Expenses [Abstract]
Insurance	$ 15	$ 27	$ 79	$ 84
Regulatory fees and assessments	15	24	71	77
Sales advertising public relations	29	14	84	42
Bank operations	14	19	53	53
Litigation	0	3	7	(15)
Other	99	57	285	186
Total other expenses	$ 172	$ 144	$ 579	$ 427