Expenses - Schedule of Expenses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Other Expenses [Abstract]
Professional services	$ 80	$ 79
Sales advertising public relations	27	26
Insurance	22	32
Regulatory fees and assessments	18	27
Bank operations	11	17
Other	117	99
Total other expenses	$ 275	$ 280