Allowance for Loan Losses and Credit Quality of Loans, Average Recorded Investments on Loans Specifically Evaluated for Impairment and Interest Income Recognized (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	$ 18,806	$ 19,528	$ 20,126	$ 20,305
Interest income recognized	228	210	662	646
Originated Loans [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	18,806	19,528	20,126	20,305
Interest income recognized	228	210	662	646
Originated Loans [Member] | Commercial Loans [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	3,671	5,102	4,979	5,446
Interest income recognized	37	36	110	109
Originated Loans [Member] | Commercial Loans [Member] | C&I [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	115	433	291	449
Interest income recognized	0	0	1	1
Originated Loans [Member] | Commercial Loans [Member] | CRE [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	2,554	3,645	3,577	3,999
Interest income recognized	30	32	91	96
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	1,002	1,024	1,111	998
Interest income recognized	7	4	18	12
Originated Loans [Member] | Consumer Loans [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	7,506	7,907	7,719	8,140
Interest income recognized	98	106	300	325
Originated Loans [Member] | Consumer Loans [Member] | Dealer Finance [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	213	177	201	187
Interest income recognized	3	4	9	8
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	7,293	7,730	7,518	7,953
Interest income recognized	95	102	291	317
Originated Loans [Member] | Residential Real Estate [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	7,629	6,519	7,428	6,719
Interest income recognized	$ 93	$ 68	$ 252	$ 212