Loans Receivable - Past Due Financing Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	$ 11,111	$ 15,217
Current Loans	991,149	873,794
Total Loans	1,002,260	889,011
Accruing Loans 90 or More days Past Due	237	365
Nonaccrual Loans	4,442	5,042
Residential Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	221	503
Loans 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	7,199	12,640
Loans 90 or More Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	3,912	2,577
Acquired loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,009	843
Current Loans	7,275	9,526
Total Loans	8,284	10,368
Accruing Loans 90 or More days Past Due	235	0
Nonaccrual Loans	582	1,367
Acquired loans \| Loans 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	521	208
Acquired loans \| Loans 90 or More Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	488	635
Residential \| Real estate:
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	3,151	9,279
Current Loans	404,693	333,405
Total Loans	407,844	342,684
Accruing Loans 90 or More days Past Due	235	0
Nonaccrual Loans	2,207	1,828
Residential \| Real estate: \| Loans 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,070	8,311
Residential \| Real estate: \| Loans 90 or More Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	2,081	968
Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,010	2,130
Current Loans	121,254	106,852
Total Loans	122,264	108,982
Accruing Loans 90 or More days Past Due	0	0
Nonaccrual Loans	749	1,067
Commercial \| Loans 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	612	1,219
Commercial \| Loans 90 or More Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	398	911
Commercial \| Real estate:
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	3,177	461
Current Loans	275,514	259,392
Total Loans	278,691	259,853
Accruing Loans 90 or More days Past Due	0	0
Nonaccrual Loans	1,486	1,648
Commercial \| Real estate: \| Loans 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,746	128
Commercial \| Real estate: \| Loans 90 or More Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	1,431	333
Construction \| Real estate:
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	0	280
Current Loans	157,586	144,652
Total Loans	157,586	144,932
Accruing Loans 90 or More days Past Due	0	280
Nonaccrual Loans	0	499
Construction \| Real estate: \| Loans 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	0	0
Construction \| Real estate: \| Loans 90 or More Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	0	280
Consumer \| Credit card
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	3,773	3,067
Current Loans	30,900	28,440
Total Loans	34,673	31,507
Accruing Loans 90 or More days Past Due	2	85
Nonaccrual Loans	0	0
Consumer \| Credit card \| Loans 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	3,771	2,982
Consumer \| Credit card \| Loans 90 or More Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	2	85
Consumer \| Other consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	0	0
Current Loans	1,202	1,053
Total Loans	1,202	1,053
Accruing Loans 90 or More days Past Due	0	0
Nonaccrual Loans	0	0
Consumer \| Other consumer \| Loans 30-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	0	0
Consumer \| Other consumer \| Loans 90 or More Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due Loans	$ 0	$ 0

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

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Financing receivables that are current.

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Recorded Investment in financing receivables that are past due at the balance sheet date.

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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