Revenue From Contracts With Customers (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Total interest income	$ 291,332	$ 293,593	$ 304,559
Service charges on deposit accounts	2,658	3,611	3,730
Other commissions and fees	9,721	10,170	11,008
Leased equipment income	12,251	10,648	9,282
Gain on sale of loans and leases	87	23	0
Gain on sale of securities	182	184	2,161
Other income	4,201	2,540	4,883
Total noninterest income	29,100	$ 27,176	31,064
Revenues	320,432		335,623
Service charges on deposit accounts	7,148		8,639
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	2,658		3,730
Other commissions and fees
Disaggregation of Revenue [Line Items]
Service charges on deposit accounts	4,154		4,538
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	336		371
Noninterest Income
Disaggregation of Revenue [Line Items]
Service charges on deposit accounts	$ 7,148		$ 8,639

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

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