Loans Receivable and Allowance for Loan Losses, Classes of Loan Portfolio by Aging Categories of Performing and Nonaccrual Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	$ 1,954	$ 7,520
Current	666,197	602,758
Net loans receivable	668,151	610,278
Non-Accrual	5,710	9,852
Loans in nonaccrual status	688	933
Actual interest income recorded on nonaccrual loans	282	427
30-59 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	1,954	1,616
60-89 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	2,245
90+ Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	3,659
Residential Mortgage [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	1,006	4,510
Current	283,640	253,149
Net loans receivable	284,646	257,659
Non-Accrual	3,891	3,580
Residential Mortgage [Member] | 30-59 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	1,006	1,472
Residential Mortgage [Member] | 60-89 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	2,074
Residential Mortgage [Member] | 90+ Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	964
Commercial [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	0
Current	37,356	46,468
Net loans receivable	37,356	46,468
Non-Accrual	78	151
Commercial [Member] | 30-59 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	0
Commercial [Member] | 60-89 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	0
Commercial [Member] | 90+ Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	0
Commercial Real Estate [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	948	686
Current	235,354	195,024
Net loans receivable	236,302	195,710
Non-Accrual	159	2,938
Commercial Real Estate [Member] | 30-59 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	948	0
Commercial Real Estate [Member] | 60-89 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	171
Commercial Real Estate [Member] | 90+ Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	515
ADC [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	112
Current	93,060	89,990
Net loans receivable	93,060	90,102
Non-Accrual	314	269
ADC [Member] | 30-59 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	106
ADC [Member] | 60-89 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	0
ADC [Member] | 90+ Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	6
Home Equity/2nds[Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	2,208
Current	15,703	16,921
Net loans receivable	15,703	19,129
Non-Accrual	1,268	2,914
Home Equity/2nds[Member] | 30-59 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	34
Home Equity/2nds[Member] | 60-89 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	0
Home Equity/2nds[Member] | 90+ Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	2,174
Consumer [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	4
Current	1,084	1,206
Net loans receivable	1,084	1,210
Non-Accrual	0	0
Consumer [Member] | 30-59 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	4
Consumer [Member] | 60-89 Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	0	0
Consumer [Member] | 90+ Days Past Due [Member]
Classes of the loan portfolio summarized by the aging categories of performing loans and nonaccrual loans [Abstract]
Total Past Due	$ 0	$ 0