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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Loans and Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	$ 651,046		$ 566,347	$ 547,040
Net deferred loan costs	7,317		5,288
Allowance for loan losses	(6,310)	$ (5,939)	(5,457)	(5,403)	$ (5,478)	$ (5,876)
Total net loans	652,053		566,178
Commercial and industrial
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	79,055		67,650	60,706
Allowance for loan losses	(1,055)	(1,082)	(879)	(333)	(574)	(775)
Commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	224,699		211,193	204,793
Allowance for loan losses	(870)	(947)	(1,305)	(966)	(936)	(1,092)
Commercial real estate \| Construction
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	10,407		5,621
Commercial real estate \| Non-residential
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	201,913		192,469
Commercial real estate \| Multifamily
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	12,379		13,103
Residential
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	44,388		43,300	41,417
Allowance for loan losses	(474)	(513)	(455)	(591)	(585)	(1,231)
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	302,905		244,204	240,124
Allowance for loan losses	(3,911)	$ (3,397)	(2,818)	$ (3,513)	$ (3,383)	$ (2,778)
Consumer \| Indirect automobile
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	272,892		214,823
Consumer \| Home equity
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	19,559		19,452
Consumer \| Other consumer
Loans and Leases Receivable Disclosure [Line Items]
Total gross loans	$ 10,453		$ 9,929