Loan and Lease Financings (Details 3) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	$ 5,424,982	$ 5,060,613
90 Days or More Past Due and Accruing	115	311
Total Accruing Loans	5,428,913	5,075,738
Nonaccrual	60,388	9,789
Total loans and leases	5,489,301	5,085,527
Increase in interest income	3,490	690	$ 2,180
Commercial and agricultural
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	1,472,755	1,131,704
Total Accruing Loans	1,472,789	1,131,822
Nonaccrual	5,933	969
Total loans and leases	1,478,722	1,132,791
Auto and light truck
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	504,659	586,212
Total Accruing Loans	505,424	587,557
Nonaccrual	36,945	1,250
Total loans and leases	542,369	588,807
Medium and heavy duty truck
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	278,452	293,736
Total Accruing Loans	278,452	293,750
Nonaccrual	720	1,074
Total loans and leases	279,172	294,824
Aircraft
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	860,632	772,846
Total Accruing Loans	860,632	783,165
Nonaccrual	828	875
Total loans and leases	861,460	784,040
Construction equipment
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	701,124	702,671
Total Accruing Loans	702,515	704,099
Nonaccrual	12,373	1,352
Total loans and leases	714,888	705,451
Commercial real estate
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	968,370	906,468
Total Accruing Loans	968,370	906,526
Nonaccrual	1,494	1,651
Total loans and leases	969,864	908,177
Residential real estate and home equity
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	508,532	528,844
90 Days or More Past Due and Accruing	108	257
Total Accruing Loans	509,661	529,814
Nonaccrual	1,718	2,189
Total loans and leases	511,379	532,003
Consumer
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Current	130,458	138,132
90 Days or More Past Due and Accruing	7	54
Total Accruing Loans	131,070	139,005
Nonaccrual	377	429
Total loans and leases	131,447	139,434
30 to 59 Days Past Due
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	2,973	10,496
30 to 59 Days Past Due | Commercial and agricultural
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	34	118
30 to 59 Days Past Due | Auto and light truck
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	560	1,268
30 to 59 Days Past Due | Medium and heavy duty truck
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	0	14
30 to 59 Days Past Due | Aircraft
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	0	7,026
30 to 59 Days Past Due | Construction equipment
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	1,093	819
30 to 59 Days Past Due | Commercial real estate
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	0	58
30 to 59 Days Past Due | Residential real estate and home equity
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	782	561
30 to 59 Days Past Due | Consumer
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	504	632
60 to 89 Days Past Due
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	843	4,318
60 to 89 Days Past Due | Commercial and agricultural
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	0	0
60 to 89 Days Past Due | Auto and light truck
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	205	77
60 to 89 Days Past Due | Medium and heavy duty truck
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	0	0
60 to 89 Days Past Due | Aircraft
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	0	3,293
60 to 89 Days Past Due | Construction equipment
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	298	609
60 to 89 Days Past Due | Commercial real estate
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	0	0
60 to 89 Days Past Due | Residential real estate and home equity
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	239	152
60 to 89 Days Past Due | Consumer
Amortized cost of loans and leases, segregated by class, with delinquency aging and nonaccrual status
Past Due	$ 101	$ 187