Revenue From Contracts With Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Disaggregation of Revenue [Line Items]
Total interest income	$ 273,337	$ 272,176	$ 291,332
Service charges on deposit accounts	2,934	3,119	2,658
Other commissions and fees	9,158	9,974	9,721
Leased equipment income	11,354	9,440	12,251
Gain on sale of loans and leases	139	1,671	87
Gain on sale of securities	101	4	182
Other income	21,143	15,642	4,201
Total noninterest income	44,829	$ 39,850	29,100
Revenues	318,166		320,432
Service charges on deposit accounts	5,971		7,148
Interest Income
Disaggregation of Revenue [Line Items]
Service charges on deposit accounts	0		0
Service charges on deposit accounts
Disaggregation of Revenue [Line Items]
Service charges on deposit accounts	2,934		2,658
Other commissions and fees
Disaggregation of Revenue [Line Items]
Service charges on deposit accounts	2,857		4,154
Leased equipment income
Disaggregation of Revenue [Line Items]
Service charges on deposit accounts	0		0
Gain on sale of loans
Disaggregation of Revenue [Line Items]
Service charges on deposit accounts	0		0
Gain on sale of securities
Disaggregation of Revenue [Line Items]
Service charges on deposit accounts	0		0
Other income
Disaggregation of Revenue [Line Items]
Service charges on deposit accounts	180		336
Noninterest Income
Disaggregation of Revenue [Line Items]
Service charges on deposit accounts	$ 5,971		$ 7,148

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Amount of realized and unrealized gain (loss) on investment.

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