Allowance for Loan and Lease Losses (the "Allowance") - Allowance allocated by portfolio segment (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Impaired Loans
Allowance on loans and leases individually evaluated for impairment	$ 133	$ 103
Allowance on loans and leases collectively evaluated for impairment	8,243	7,950
Total	8,376	8,053	$ 7,138	$ 6,709
Carrying value of loans and leases individually evaluated for impairment	5,601	5,799
Carrying value of loans and leases collectively evaluated for impairment	845,635	822,566
Total	851,236	828,365
Commercial mortgage
Impaired Loans
Allowance on loans and leases collectively evaluated for impairment	3,163	3,209
Total	3,163	3,209	2,566	2,434
Carrying value of loans and leases individually evaluated for impairment	1,921	1,929
Carrying value of loans and leases collectively evaluated for impairment	323,922	323,464
Total	325,843	325,393
Home equity lines and loans
Impaired Loans
Allowance on loans and leases collectively evaluated for impairment	341	323
Total	341	323	262	280
Carrying value of loans and leases individually evaluated for impairment	81	83
Carrying value of loans and leases collectively evaluated for impairment	81,858	82,203
Total	81,939	82,286
Residential mortgage
Impaired Loans
Allowance on loans and leases collectively evaluated for impairment	212	191
Total	212	191	127	82
Carrying value of loans and leases individually evaluated for impairment	857	969
Carrying value of loans and leases collectively evaluated for impairment	43,996	40,969
Total	44,853	41,938
Construction
Impaired Loans
Allowance on loans and leases collectively evaluated for impairment	1,802	1,627
Total	1,802	1,627	1,861	1,689
Carrying value of loans and leases individually evaluated for impairment	1,294	1,281
Carrying value of loans and leases collectively evaluated for impairment	126,369	115,625
Total	127,663	116,906
Commercial and industrial
Impaired Loans
Allowance on loans and leases individually evaluated for impairment	133	103
Allowance on loans and leases collectively evaluated for impairment	2,713	2,587
Total	2,846	2,690	2,315	2,214
Carrying value of loans and leases individually evaluated for impairment	1,448	1,537
Carrying value of loans and leases collectively evaluated for impairment	267,580	258,269
Total	269,028	259,806
Consumer
Impaired Loans
Allowance on loans and leases collectively evaluated for impairment	4	3
Total	4	3	3	5
Carrying value of loans and leases collectively evaluated for impairment	751	701
Total	751	701
Leases, net
Impaired Loans
Allowance on loans and leases collectively evaluated for impairment	8	10
Total	8	10	$ 4	$ 5
Carrying value of loans and leases collectively evaluated for impairment	1,159	1,335
Total	$ 1,159	$ 1,335

The balance of financing receivables excluding loans and leases carried at fair value.

No definition available.

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- Definition

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

+ References

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

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- Definition

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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