Other Noninterest Expense - Summary of Other Noninterest Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Other Income and Expenses [Abstract]
Outside processing	$ 13,913	$ 5,474
Loan and lease expense	7,783	3,289
Professional fees	6,569	5,528
Advertising and marketing	8,377	6,855
FDIC insurance	6,559	2,918
Card processing and issuance costs	8,690	4,508
Other	36,855	25,507
Total other noninterest expense	$ 88,746	$ 54,079