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		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	$ 20,857	$ 20,257	$ 20,947	$ 20,668
Interest income recognized	220	214	434	436
Originated Loans [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	20,857	20,257	20,947	20,668
Interest income recognized	220	214	434	436
Originated Loans [Member] | Commercial Loans [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	5,628	5,373	5,790	5,599
Interest income recognized	36	36	73	73
Originated Loans [Member] | Commercial Loans [Member] | C&I [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	326	447	383	457
Interest income recognized	0	1	1	1
Originated Loans [Member] | Commercial Loans [Member] | CRE [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	4,212	3,882	4,248	4,154
Interest income recognized	31	32	61	64
Originated Loans [Member] | Commercial Loans [Member] | Business Banking [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	1,090	1,044	1,159	988
Interest income recognized	5	3	11	8
Originated Loans [Member] | Consumer Loans [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	7,774	8,146	7,834	8,254
Interest income recognized	102	107	202	219
Originated Loans [Member] | Consumer Loans [Member] | Dealer Finance [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	221	194	198	188
Interest income recognized	4	1	6	4
Originated Loans [Member] | Consumer Loans [Member] | Direct [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	7,553	7,952	7,636	8,066
Interest income recognized	98	106	196	215
Originated Loans [Member] | Residential Real Estate [Member]
Average Recorded Investment and Interest Income Recognized [Abstract]
Average recorded investment	7,455	6,738	7,323	6,815
Interest income recognized	$ 82	$ 71	$ 159	$ 144