Other Noninterest Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Other Income and Expenses [Abstract]
Lending and other client related processing costs	$ 29,783	$ 28,491	$ 24,237
Correspondent bank fees	15,065	14,503	13,713
Investment banking activities	20,591	13,733	0
Trade order execution costs	11,144	10,813	0
Data processing services	14,910	12,536	10,811
Telephone	8,591	9,861	9,404
Dues and publications	4,251	4,603	4,605
Postage and supplies	2,545	3,198	2,799
Other	83,295	54,841	21,682
Total other noninterest expense	$ 190,175	$ 152,579	$ 87,251