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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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Allowance for Loan Losses and Reserve for Unfunded Lending Commitments - Allowance by Portfolio Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2018	Dec. 31, 2017
Allowance for Loan Losses
Balance, beginning of year	$ 13,603	$ 12,801	$ 12,601
Charge-offs	(1,020)	(690)	(326)
Recoveries	325	476	276
Provision	(103)	1,016	250
Balance, end of year	12,805	13,603	12,801
Allowance for Loan Losses
Individually evaluated for impairment				$ 64	$ 167
Collectively evaluated for impairment				12,560	13,151
Total	13,603	12,801	12,601	12,805	13,603
Loans
Individually evaluated for impairment				1,334	3,217
Collectively evaluated for impairment				1,335,531	1,309,478
Loans, net of unearned income				1,357,476	1,336,125
Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses
Balance, beginning of year	285
Balance, end of year	181	285
Allowance for Loan Losses
Total	285	285		181	285
Loans
Loans, net of unearned income				20,611	23,430
Commercial
Allowance for Loan Losses
Balance, beginning of year	2,413	2,095
Charge-offs	(787)	(282)
Recoveries	69	223
Provision	842	377
Balance, end of year	2,537	2,413	2,095
Allowance for Loan Losses
Individually evaluated for impairment				55	154
Collectively evaluated for impairment				2,482	2,259
Total	2,413	2,095	2,095	2,537	2,413
Loans
Individually evaluated for impairment				90	206
Collectively evaluated for impairment				285,431	251,185
Loans, net of unearned income				285,972	251,666
Commercial \| Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses
Balance, beginning of year	0
Balance, end of year	0	0
Allowance for Loan Losses
Total	0	0		0	0
Loans
Loans, net of unearned income				451	275
Commercial real estate
Allowance for Loan Losses
Balance, beginning of year	8,321	7,355
Charge-offs	(11)	(93)
Recoveries	10	60
Provision	(1,074)	999
Balance, end of year	7,246	8,321	7,355
Allowance for Loan Losses
Individually evaluated for impairment				0	0
Collectively evaluated for impairment				7,211	8,203
Total	8,321	7,355	7,355	7,246	8,321
Loans
Individually evaluated for impairment				376	862
Collectively evaluated for impairment				742,365	747,819
Loans, net of unearned income				753,040	760,848
Commercial real estate \| Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses
Balance, beginning of year	118
Balance, end of year	35	118
Allowance for Loan Losses
Total	118	118		35	118
Loans
Loans, net of unearned income				10,299	12,167
Residential real estate
Allowance for Loan Losses
Balance, beginning of year	2,825	3,303
Charge-offs	(86)	(172)
Recoveries	149	85
Provision	89	(391)
Balance, end of year	2,977	2,825	3,303
Allowance for Loan Losses
Individually evaluated for impairment				9	13
Collectively evaluated for impairment				2,822	2,645
Total	2,825	3,303	3,303	2,977	2,825
Loans
Individually evaluated for impairment				868	2,144
Collectively evaluated for impairment				302,657	306,066
Loans, net of unearned income				313,371	319,183
Residential real estate \| Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses
Balance, beginning of year	167
Balance, end of year	146	167
Allowance for Loan Losses
Total	167	167		146	167
Loans
Loans, net of unearned income				9,846	10,973
Consumer
Allowance for Loan Losses
Balance, beginning of year	44	48
Charge-offs	(136)	(143)
Recoveries	97	108
Provision	40	31
Balance, end of year	45	44	48
Allowance for Loan Losses
Individually evaluated for impairment				0	0
Collectively evaluated for impairment				45	44
Total	44	48	$ 48	45	44
Loans
Individually evaluated for impairment				0	5
Collectively evaluated for impairment				5,078	4,408
Loans, net of unearned income				5,093	4,428
Consumer \| Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses
Balance, beginning of year	0
Balance, end of year	0	0
Allowance for Loan Losses
Total	$ 0	$ 0		0	0
Loans
Loans, net of unearned income				$ 15	$ 15