Loans (Information on Non-Accrual Loans) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual loans	$ 7,678	$ 5,026	$ 8,501
Loans 90 day past due and accruing		164
Total non-performing loans	7,678	5,190	8,501
Interest income that would have been recorded under original terms, non-accrual loans	156	104
Interest income that would have been recorded under original terms, 90 days past due and accruing		1
Interest income that would have been recorded under original terms	156	105
Interest income recorded during the period, 90 days past due and accruing		1
Interest income recorded during the period		1
Net impact on interest income, non-accrual loans	156	104
Net impact on interest income	156	104
Residential Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual loans	1,845	1,781	1,770
Interest income that would have been recorded under original terms, non-accrual loans	21	19
Net impact on interest income, non-accrual loans	21	19
Commercial Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual loans	1,885	1,025	4,593
Interest income that would have been recorded under original terms, non-accrual loans	41	20
Net impact on interest income, non-accrual loans	41	20
Commercial Term [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual loans	1,986	210	198
Interest income that would have been recorded under original terms, non-accrual loans	38	3
Net impact on interest income, non-accrual loans	38	3
Commercial Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual loans	1,248	1,237	1,242
Interest income that would have been recorded under original terms, non-accrual loans	45	41
Net impact on interest income, non-accrual loans	45	41
Consumer: Home Equity [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual loans	460	574	442
Interest income that would have been recorded under original terms, non-accrual loans	6	16
Net impact on interest income, non-accrual loans	6	16
Consumer: Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual loans	254	199	$ 256
Interest income that would have been recorded under original terms, non-accrual loans	5	5
Net impact on interest income, non-accrual loans	$ 5	$ 5