Loans - Additional Information (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2020 USD ($) loan	Jun. 30, 2019 USD ($) loan	Jun. 30, 2020 USD ($) loan	Jun. 30, 2019 USD ($) loan	Dec. 31, 2019 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net unamortized loan fees	$ 9,313,000		$ 9,313,000		$ 3,092,000
Percentage of comprised loan, commercial, industrial and agricultural loans	42.00%		42.00%		37.00%
Percentage of comprised loan, commercial mortgage loans	29.00%		29.00%		29.00%
Percentage of loan-to-value to business equipment			80.00%
Percentage of loan-to-value to accounts receivable			70.00%
Percentage of loan-to-value to business inventory			60.00%
Percentage of loan-to-value to real estate			85.00%
Percentage of residential real estate loan in portfolio	27.00%		27.00%		29.00%
Minimum period to be considered for loan to have defaulted			90 days
Loans modified as troubled debt restructuring with subsequent defaults | loan			0	0
Principal balances forgiven in connection with loan restructuring	$ 0		$ 0
Number of loans, period of time | loan	9	0	9	0
Modified in a troubled debt restructuring	$ 11,113,000		$ 11,113,000		$ 9,802,000
Financing receivable, allowance for credit losses, w-downs	$ 3,191,000	$ 773,000	$ 4,101,000	$ 1,576,000
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum percentage of consumer loan and credit card in portfolio	3.00%		3.00%