Revenue From Contracts With Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Disaggregation of Revenue [Line Items]
Total interest income	$ 280,505	$ 273,337	$ 274,075	$ 553,842	$ 565,407
Service charges on deposit accounts	3,452	2,934	2,004	6,386	4,662
Other commissions and fees	10,704	9,158	10,111	19,862	19,832
Leased equipment income	10,847	11,354	12,037	22,201	24,288
Gain on sale of loans and leases	1,422	139	346	1,561	433
Gain on sale of securities	0	101	7,715	101	7,897
Other income	13,946	21,143	6,645	35,089	10,846
Total noninterest income	40,371	$ 44,829	38,858	85,200	67,958
Revenues	320,876		312,933	639,042	633,365
Service charges on deposit accounts	6,449		5,346	12,420	12,494
Interest Income
Disaggregation of Revenue [Line Items]
Revenues				553,842	565,407
Service charges on deposit accounts	0		0	0	0
Service charges on deposit accounts
Disaggregation of Revenue [Line Items]
Revenues				6,386	4,662
Service charges on deposit accounts	3,452		2,004	6,386	4,662
Other commissions and fees
Disaggregation of Revenue [Line Items]
Revenues				19,862	19,832
Service charges on deposit accounts	2,603		3,006	5,460	7,160
Leased equipment income
Disaggregation of Revenue [Line Items]
Revenues				22,201	24,288
Service charges on deposit accounts	0		0	0	0
Gain on sale of loans
Disaggregation of Revenue [Line Items]
Revenues				1,561	433
Service charges on deposit accounts	0		0	0	0
Gain on sale of securities
Disaggregation of Revenue [Line Items]
Revenues				101	7,897
Service charges on deposit accounts	0		0	0	0
Other income
Disaggregation of Revenue [Line Items]
Revenues				35,089	10,846
Service charges on deposit accounts	394		336	574	672
Noninterest Income
Disaggregation of Revenue [Line Items]
Revenues				85,200	67,958
Service charges on deposit accounts	$ 6,449		$ 5,346	$ 12,420	$ 12,494