Loans - Schedule of Net Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Loan Portfolio By Loan Grade [Line Items]
Loans and leases receivable, gross	$ 2,855,206	$ 2,809,197
Less: unearned discount	(4,546)	(5,162)
allowance for loan losses	(21,915)	(19,473)	$ (20,346)	$ (19,704)
Net loans	2,828,745	2,784,562
Commercial, industrial and agricultural
Loan Portfolio By Loan Grade [Line Items]
Loans and leases receivable, gross	1,090,915	1,046,665
allowance for loan losses	(10,532)	(8,287)	(7,787)	(7,341)
Net loans	1,090,915	1,046,665
Commercial mortgages
Loan Portfolio By Loan Grade [Line Items]
Loans and leases receivable, gross	846,215	814,002
allowance for loan losses	(7,492)	(6,952)	(8,846)	(7,490)
Net loans	846,215	814,002
Residential real estate
Loan Portfolio By Loan Grade [Line Items]
Loans and leases receivable, gross	814,657	814,030
allowance for loan losses	(1,458)	(1,499)	(1,383)	(2,156)
Net loans	814,657	814,030
Consumer
Loan Portfolio By Loan Grade [Line Items]
Loans and leases receivable, gross	94,425	124,785
allowance for loan losses	(2,138)	(2,411)	(2,040)	(2,377)
Net loans	94,425	124,785
Credit cards
Loan Portfolio By Loan Grade [Line Items]
Loans and leases receivable, gross	8,683	7,569
allowance for loan losses	(112)	(84)	(105)	(103)
Net loans	8,683	7,569
Overdrafts
Loan Portfolio By Loan Grade [Line Items]
Loans and leases receivable, gross	311	2,146
allowance for loan losses	$ (183)	$ (240)	$ (185)	$ (237)

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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